4 NYSDJ • APRIL 2007
BY NOW, THE TERM EVIDENCE-BASED DENTISTRY has become
something of a cliché, having been bantered around in practically
every dental publication and in many ofthe presentations and forums
we attend. There is no doubt that the development ofclinical protocols
that are based upon meaningful investigations, investigations that
meet the “gold standard”of fundamental research design and imple-
mentation,is a priority on dentistry’s agenda.But this admirable quest
is fraught with potential problems and challenges,while still holding
out hope ofbenefits to both the dental practitioner and to our patients.
Identifying areas of clinical practice that merit further investi-
gation must rely upon input from clinicians themselves to maxi-
mize the benefits to individual patients and/or the profession at
large.The “so what?”criteria should be met so that measurable dif-
ferences that might potentially be found in clinical outcomes—if
that is what is being investigated—represent a meaningful state-
ment that could and should have an impact upon cogent recom-
mendations for changes in clinical treatment protocols.
The role of the clinician as an important member of the
research team now becomes more important than ever.As such,the
clinical dentist and dentist researcher/academic and biostatistician
must have an unprecedented dialogue and relationship.
Dental education on the predoctoral and postdoctoral levels
will also have an opportunity to broaden research design perspec-
tives and will be a significant benefit for all of us.While the ability
to critically assess the professional literature found in our peer
reviewed publications has always been and will continue to be an
important responsibility of all dentists, editors and editorial
boards, the expectations for clinician participation in small and
large research projects will undoubtedly be raised.
The National Institute of Dental and Craniofacial Research
(NIDCR) has taken a bold and proactive position in forging a new
model for clinical research in dentistry.Practice-based research net-
works (PBRNs) have been utilized in medicine,and this has result-
ed in significant clinical protocol changes. Similarly, the PBRN
structure,as envisioned by the NIDCR,is an inclusive concept that
combines the rigorous standards of academic research with the
practical demands of clinical practice.As such,the NIDCR commit-
ted approximately $75 million, over seven years, to three dental
PBRNs.Each PBRN will be mandated to recruit at least 100 general
dental practitioners as participants in the PBRN investigation pro-
jects.This unprecedented hybrid structure of clinical investigation
represents the ultimate meeting of“town and gown”in dentistry.
One of the three dental PBRNs is based in the Northeast and
was awarded to New York University College of Dentistry and The
EMMES Corp. from Rockville, Maryland. It is referred to as the
PEARL Network, an abbreviation for Practitioners Engaged in
Applied Research and Learning.I am certain we will be hearing a
great deal more about all of these dental PBRNs in the near future.
As the dental profession charts its course ofcontinued excellence
and relevance to the public in this millennium,clinical research will
play a powerful role in the process.Indeed,the rules of engagement
have been profoundly changed.What an exciting time for all of us!
Clinical Research in Dentistry
Everything is up for change, from research design to treatment protocols.
The times couldn’t be more challenging, or exciting.
NYSDJ • AUGUST/SEPTEMBER 2006 5
Stony Brook, NY 11790
NYSDJ • APRIL 2007 5
Steven Gounardes, President
351 87th St., Brooklyn 11209
Stephen B. Gold, President Elect
8 Medical Drive, Port Jefferson Station 11776
Michael R. Breault, Vice President
1368 Union St., Schenectady 12308
John Asaro, Secretary-Treasurer
2707 Sheridan Drive, Tonawanda 14150
Alfonso J. Perna, Immediate Past President
Sixth District Dental Society, 55 Oak St.
Roy E. Lasky, Executive Director
121 State St., Albany 12207
William R. Calnon, ADA Trustee
3220 Chili Ave., Rochester, NY 14624
NY County-Lawrence Bailey
215 W. 125th St., New York 10027
NY County-Matthew J. Neary
501 Madison Ave., Fl. 22, New York 10022
NY County-Robert B. Raiber
630 Fifth Ave., #1869, New York 10111
2-Michael L. Cali
2003 E. 60th St., #1A, Brooklyn 11234
2-Craig S. Ratner
1011 Richmond Rd., Staten Island 10304-2413
2-James J. Sconzo
1666 Marine Parkway, Brooklyn 11234
3-Lawrence J. Busino
2 Executive Park Dr., Albany 12203
3-John P. Essepian
180 Old Loudon Rd., Latham 12110
4-Mark A. Bauman
157 Lake Ave., Saratoga Springs 12866
4-Frederick W. Wetzel
1556 Union St., Niskayuna 12309
5-William H. Karp
472 S. Salina St., #222, Syracuse 13202
5-John J. Liang
2813 Genessee St., Utica 13501
6-Robert W. Baker, Jr.
412 N. Tioga St., Ithaca 14850
39 Leroy St., Binghamton 13905
7-Richard F. Andolina
74 Main St., Hornell 14843
7-Andrew G. Vorrasi
2005-A Lyell Ave., Rochester 14606
8- Jeffrey A. Baumler
2145 Lancelot Dr., Niagara Falls 14304
8- Kevin J. Hanley
959 Kenmore Ave., Buffalo 14223-3160
9-Malcolm S. Graham
170 Maple Ave., White Plains 10601
9-David H. Kraushaar
6 Woodthrush Drive, W. Nyack 10994
9- Neil R. Riesner
111 Brook St., 3rd Floor, Scarsdale 10583-5149
N- Peter M. Blauzvern
366 N. Broadway, Jericho 11753-2032
N-David J. Miller
467 Newbridge Rd., E. Meadow 11554
N-Robert M. Peskin
601 Franklin Ave., #225, Garden City 11530-5742
Q-Chad P. Gehani
35-49 82nd St., Jackson Heights 11372
Q-Robert L. Shpuntoff
28 Beverly Rd., Great Neck 11021
S-Paul R. Leary
80 Maple Ave., #206, Smithtown 11787
S-Steven I. Snyder
Suffolk Oral Surgery Associates, 264 Union Ave., Holbrook 11741
B-Stephen B. Harrison
1668 Williamsbridge Rd., Bronx 10461
B-Richard P. Herman
20 Squadron Blvd., New City 10956
BOARD OF GOVERNORS
James E. Spencer
2 Burlington Pl., Woodcliff Lake, NJ 07671
Mark J. Feldman
5 Vanad Dr., Roslyn 11576
Robert J. Herzog
16 Parker Ave., Buffalo 14214
Dental Benefit Programs
Ian M. Lerner
One Hanson Pl., #2900
Brooklyn, NY 11243-2907
Dental Health Planning/
Robert A. Seminara
281 Benedict Rd., Staten Island 10304
Brendan P. Dowd
6932 Williams Rd., #1900, Niagara Falls 14304
Dental Education & Licensure
Madeline S. Ginzburg
2600 Netherland Ave., #117
Kevin A. Henner
163 Half Hollow Rd., #1
Deer Park 11729
Joseph R. Caruso
40-29 Utopia Pky., Flushing, 11358
Roland C. Emmanuele
4 Hinchcliffe Dr.,
Newburgh, NY 12550
Deborah A. Pasquale
391 Manhattan Ave.,
David C. Bray
18 Leroy St., Binghamton 13905
Alfonsa J. Perna
Sixth District Dental Society
55 Oak St., Binghamton, NY 13905
Peer Review &
1 Rockefeller Plaza., #2201,
New York 10020-2003
Anthony V. Maresca
207 Hallock Rd.
121 State Street
Albany, NY 12207
Roy E. Lasky
Margaret Surowka Rossi
Michael J. Herrmann
Assistant Executive Director
Judith L. Shub
Assistant Executive Director
Mary Grates Stoll
Beth M. Wanek
Assistant Executive Director
Foundation to Recognize
Annual Deans Award aimed at bolstering oral
health workforce in New York State.
ENSURING A GROWING and sustainable oral
health workforce is crucial to expanding the
availability of oral health services to all New
Yorkers, particularly the underserved and mem-
bers of the state’s growing culturally diverse
communities. To help address this critical issue,
the New York State Dental Foundation has estab-
lished a Deans Award, which will be present-
ed annually to graduating students or post-
doctoral trainees who have demonstrated an
exceptional level of achievement as measured
by the following criteria:
Outstanding academic performance.
A demonstrated commitment to enhancing
and improving the oral health of under-
Membership in the American Dental Student
Candidates for the NYSDF Deans Award,
valued at $5,000, must be nominated by the
dean of each of the following academic dental
institutions: Columbia University College of
Dental Medicine; New York University College
of Dentistry; University at Buffalo School of
Dental Medicine; Stony Brook University
School of Dental Medicine; and the University
of Rochester Eastman Dental Center. Upon
review by the Foundation Board, the deans'
candidates will each be presented with a
$5,000 check at their respective commence-
“This is such a wonderful opportunity for
the Foundation to partner with the state’s den-
tal schools,” said Foundation Chair Edward J.
Downes. “At the same time, we are promoting
the value of organized dentistry, making this
new program a remarkable win-win for every-
Winners of the 2007 Deans awards are
expected to be announced soon.
12 NYSDJ • APRIL 2007
THE BOARD OF TRUSTEESofthe New York State Dental Foundation
has approved a request for funding in the amount of$10,000 from the
Chemung County-Corning Coalition for Water Fluoridation.
The Chemung County-Corning Coalition for Water Fluori-
dation is an affiliation of advocates for completion of the 25-mile
corridor of municipal water fluoridation from Chemung County to
Painted Post.The eastern portion ofChemung County has been flu-
oridated since 1953, a system that currently serves 70,000 of the
92,000 residents of the county.To the west,Painted Post has fluori-
dated since 1976,serving 9,100 residents.In the intervening years,
from initial fluoridation to today, many studies have shown that
children in the non-fluoridated 25-mile corridor exhibited elevated
numbers of decayed,missing and filled teeth.
Following a decades-long struggle against vitriolic anti-fluori-
dationists, public health advocates were able to successfully lobby
the Corning Board of Health and the Corning City Council to agree
to fluoridate the remaining water supply.The one catch was that the
Chemung County-Corning Coalition for Water Fluoridation would
have to come up with $100,000, half of the capital costs to start
water fluoridation, hence, the request for funding from the New
York State Dental Foundation.
“We were greatly impressed by the level of support garnered
for this project from all possible stakeholders but most notably
from the local dental communities,” said Foundation Vice
Chairman Robert Raiber.By the time the coalition made its appeal
the NYSDF, it had already received $11,000 in pledges from indi-
vidual,local dentists; a $2,500 donation from the Steuben County
Dental Society; and a $10,000 donation from the Seventh District
Dental Society. In addition, the Ferraioli Dental Lecture has
Among the NYSDF’s missions is the goal of increasing public
understanding of and access to dental services. Clearly, fluorida-
tion is an essential aspect of oral health. The Centers for Disease
Control has called fluoridation one of the 10 greatest public health
achievements of the 20th century.In its “MMWR Weekly,”the CDC
“Fluoridation of drinking water began in 1945 and in 1999
reached an estimated 144 million persons in the United States.
Fluoridation safely and inexpensively benefits both children and
adults by effectively preventing tooth decay, regardless of socioeco-
nomic status or access to care.Fluoridation has played an important
role in the reductions of tooth decay (40% - 70% in children) and of
tooth loss in adults (40% - 60%).”
The Foundation commends the hard work and efforts of the
Chemung County-Corning Coalition for Water Fluoridation and is
thankful for the opportunity to support and assist efforts to
improve the oral health of all New Yorkers.
Foundation Honors Eisenbud
The Board of Trustees of the New York State Dental Foundation
recently honored the memory and outstanding achievements of Dr.
Leon Eisenbud,with a contribution of $1,000 to a campaign to ren-
$10,000 for Fluoridation
NYSDJ • APRIL 2007 13
ovate and rename the dental department at Long Island Jewish
Medical Center in his honor.
“Dr. Eisenbud,” said Foundation Chair Edward Downes,“will
long be remembered by members of our Board as well as the lead-
ership of the New York State Dental Association as the ‘father of the
modern dental residency program.’”
In a letter written in the fall of 2002 to NYSDA Executive
Director Roy E.Lasky,Dr.Eisenbud called passage ofthe PGY-1 leg-
islation “a grand achievement”and referred to the State Board exam
process as “archaic and unfair”:
“…I am writing now to congratulate you on this grand
achievement,which indeed was only a dream.The substitution of a
residency for the unfair and archaic state board exam is the most
important step forward for the profession in my lifetime.I congrat-
ulate you because I know the way you guide things through the leg-
islative system. I think maybe this would not have happened with-
“Dr. Eisenbud’s impeccable reputation and his ability to
instruct and inform others without a doubt helped NYSDA in its
efforts to remove the exam requirement in New York State,” Dr.
A committee has been formed at Long Island Jewish Medical
Center to spearhead the campaign to rename the dental department
in Dr.Eisenbud’s memory.It is the committee’s hope that everybody
in the dental community will do what he or she can to ensure that
Dr.Eisenbud’s legacy will be appropriately memorialized. ■
H O N O R I N G
Excellence in Community Service
& Corporate Leadership
Save The Date
FOUNDATIONS OF EXCELLENCE
Friday October 12, 2007 12:00 noon to 2:00 p.m.
The St. Regis Two East 55thStreet At Fifth Avenue, NYC
14 NYSDJ • APRIL 2007
A NEW AND EXCITING TRENDin dental research is embodied by
the inauguration of three practice-based research networks funded
by the National Institute for Dental and Craniofacial Research, an
arm of the National Institutes of Health. One is based in the
Northwest,a second in the Southeast,and the third,closer to home,
at the New York University College of Dentistry. This last, the
PEARL Network— PEARL stands for Practitioners Engaged in
Applied Research and Learning—has since its inception in 2005
enrolled more than 100 practitioner-investigators and has eight
studies either underway or in the planning stages.
Practice-based research networks (PBRNs),which have exist-
ed in the United States since the 1980s but until recently only
among physicians,generate research of immediate relevance to the
profession by combining the expertise of a central academic
research center with the savvy of the practitioner working “in the
trenches.”The PBRN concept arose from recognition ofthe fact that
while the majority of clinical research is conducted in academic
health centers,only a minority of patients receive their medical or
dental care there.
In contrast,in the PBRN model,network participants—clini-
cians involved in private practice, who represent 70 percent of the
profession—submit their own ideas for research to a coordinating
academic center,where NIH-approved protocols are developed and
in turn are implemented by these same practitioners.Improvements
in clinical practice traditionally have proceeded in a top-down man-
ner: a study begins in a laboratory or academic site and ends at an
academically based faculty practice.The PBRN model seeks to com-
plement this process by including the primary means of achieving
the greatest impact in terms of change:the general practitioner.
The PBRN model furthermore seeks to make up for the lack of
data available for clinical decision making and to create a mecha-
nism for comparing clinical outcomes reported by practitioners
who have decades of experience with findings generated by acade-
mic research centers.
Dentists Make Good Candidates
In terms of the practical implementation of such a model,experi-
ence has demonstrated that private-practice dentists and their
office staff are uniquely suited to participate in network-based
research,for several reasons.They include the following:
● The research focus of PBRNs is primarily problem based.
● Dentists are trained to be detail oriented and in control of the
● The essential elements of clinical research are mirrored by the
dentist’s experience with implementing a treatment plan.
● Dedicated private-practice staff are familiar with the team
approach to clinical care, which parallels the environment
required for research coordination.
A typical dental PBRN study may last anywhere from one
month to three years,although most are of six months’duration.It
is an observational study that addresses a fundamental clinical
question:Why we do what we do; and how can we do it better? All
studies relate to the day-to-day clinical needs of private dentists
and their patients and involve minimal additional work on the part
of the practitioner. Current topics under investigation by NYUCD
PEARL Network practitioner-investigators,for example,include:
Practice-Based Research Networks
A Win-Win for Private-Practice Dentists and the Future of Dentistry
Analia Veitz-Keenan,D.D.S.;Gary S.Berkowitz,D.D.S.;Irene Brandes,D.D.S.,P.C.;
Kenneth L.Goldberg,D.M.D.;David A.Hamlin,D.M.D.;Robert Margolin,D.D.S.;Kay Oen,D.D.S.
P E R S P E C T I V E S
NYSDJ • APRIL 2007 15
● Causes of postoperative hypersensitivity in Class I composite
● The effects of partial vs. complete caries removal on patient
Studies in the planning stages deal with:
● The effects of endodontic therapy and restoration on tooth
● The effects ofsealing vs.restoration on caries extending into dentin.
Time Well Spent
While the individual dentist’s involvement in a PBRN involves a
substantial personal commitment of time and effort,most practi-
tioner-investigators regard the rewards of their participation as
more than commensurate.For example:
● Participation in cutting-edge research has a positive impact on
the practitioner-investigator’s practice in addition to leading
to improvements in the practice of dentistry.
● The Network practitioner-investigator gains training in the
methods and ethics of clinical research from specially trained
Network personnel—a “gift that keeps on giving.”
● Network administration assumes the burden of paperwork
necessary for study approval and reporting,thereby freeing up
the practitioner-investigator to concentrate on the nuts and
bolts of the study.
● The private-practice dentist,who is typically isolated from the
research environment, enjoys a new collegiality with other
practitioner-investigators, with a prestigious academic center
and with NIH. The PBRN acts as a link connecting dental
offices,integrating these offices into a larger organization and
uniting practitioners and academic researchers.
● Participation in a Network study helps satisfy the practition-
er’s continuing education requirements.
More and more dentists are viewing PBRNs as a means for becom-
ing involved with the advancement of the profession by applying
scientific guidelines to generate significant—and practice-applica-
ble—clinical data. PBRNs function at the interface between
research and quality improvement.They have the potential to have
a substantial impact on dentistry by adding a learning dimension
to the dental practice while improving primary dental care and cre-
ating a connected learning community.They provide opportunities
to address patient-centered issues that previously were neglected.
The ultimate measure of the success of dental PBRNs will be
their ability to influence dentistry,to change clinical procedures on
the basis of objective and reproducible evidence gathered by multi-
ple practitioners representing a wide range of patients, clinical
expertise and office locations. ■
The authors are all practitioner-investigators in the PEARL network and members of
the PEARL Practitioner Advisory Group.More information on the PEARL Network
is available at http://www.pearlnetwork.org/
16 NYSDJ • APRIL 2007
THE DENTAL SCHOOL OF COLUMBIA UNIVERSITY officially
opened on September 27, 1916, with a combined MD/DDS pro-
gram. Dr.Joseph Schroff was the first recipient of a dental degree
from Columbia,in 1922.
Fast forward almost 100 years and we are witness to outstand-
ing contributions to the dental profession by the teachers and gradu-
ates of what is now Columbia University College of Dental Medicine.
TheNYSDJhad an opportunity to visit with Ira Lamster,D.D.S.,M.M.Sc.,
dean ofthe College ofDental Medicine.In the interview that follows,Dr.
Lamster illuminates Columbia University’s unique approach and com-
mitment to dental education,research,clinical training and communi-
ty service in an ever-changing and complex health care environment.
Dr. Moskowitz: You have been dean of the Columbia University
College of Dental Medicine for approximately five years. How are
you enjoying the job?
Dean Lamster: I enjoy my job immensely. I am fortunate to
work with a fine faculty,who are intelligent and dedicated.Our den-
tal students and postdoctoral students are very bright and motivat-
ed.In addition,the College of Dental Medicine is positioned within
the Columbia University Medical Center,which is a remarkably col-
laborative institution with many outstanding health care scientists
and clinicians in medicine,public health and nursing.Many of our
academic,research and patient care programs occur in the context
of the health sciences, and that is the best position for a dental
school to be in. The job of dean has its challenges, and there are
many demands on your time and energy.This is not a job you can
do effectively unless you believe in your school.
Dr.Moskowitz:Are there any special challenges for Columbia
University College of Dental Medicine because of its location in a
large urban area?
Dean Lamster: Being in an urban setting provides challenges
and opportunities. The patients we serve are often those who have
difficulty accessing services,and they present with a significant dis-
ease burden.On the other hand, there is enormous satisfaction for
our trainees when they provide a service that changes a person’s abil-
ity to function or smile.In addition,we have a large pediatric den-
tistry service,and starting children in the right direction is a major
accomplishment that can prevent a lifetime of dental problems.
Dr. Moskowitz: Historically, deans of dental schools have
been somewhat inaccessible or, at least, not terribly visible to the
profession at large.You,however,are very visible in the dental pro-
A CONVERSATION WITH IRA LAMSTER
Dean of Columbia University College of Dental Medicine talks about challenges
and rewards of sitting at the helm of one of America’s premier dental schools.
Editor,The New York State Dental Journal
NYSDJ Editor Elliott Moskowitz, left, discusses issues facing dental education with Columbia University College of Dental Medicine Dean Ira Lamster.
NYSDJ • APRIL 2007 17
fession.You attend dental meetings,on the local,state and national
levels,scholarly forums and associated social functions. How does
this visibility and accessibility help you in your role as dean?
Dean Lamster:It is important for a dean of a dental school to
acknowledge his or her constituency. At many of the meetings I
attend,I see our faculty and alumni.It is important to be a part of
these events.As with all of us,by being there,I can demonstrate my
feelings about the importance of an organization or a particular
meeting.I am still involved in research and still have an active NIH
grant. That is a part of my professional life, but demands on my
time are making this difficult to maintain.
Dr.Moskowitz: What is your vision for Columbia in the next
Dean Lamster: The Columbia University College of Dental
Medicine is uniquely positioned to bridge the gap between medi-
cine and dentistry.I appreciate the fact that dentistry is a distinct
profession but with close ties to medicine; therefore, defining our
role in the health care system is a critical goal for the future.We see
our predoctoral program evolving into training that allows greater
time for electives and for more interactions with medicine and
public health.We are continuing to expand our offsite clinical care
initiatives,as well as our research initiatives that look at dental and
craniofacial research in the context of health sciences research.
Dr. Moskowitz: What differences do you see in the student
body at Columbia today as compared to previous eras?
Dean Lamster:Our student body is truly outstanding.Like all
dental schools in the United States,Columbia is seeing a large num-
ber of applicants.And those accepted are among the finest students
applying to dental school.They come to us with a variety of experi-
ences prior to entering the college.Many are interested in what we
can think of as nontraditional careers, including academics,
research, business—we have a combined DDS/MBA program—
and public health/public service—we also have a combined
DDS/MPH program.Further,many of our students understand the
importance of community service and act on those beliefs while at
Dr. Moskowitz: Columbia has always been identified with
having a strong connection to the surrounding community.What is
so special about this relationship?
Dean Lamster: This effort is special because it acknowledges
that the college considers patient care to be an equal mission with
training and research.Our connection to the surrounding commu-
nity formally began in 1996 with formation of the DentCare pro-
gram, which focused on delivery of dental services to children in
the community.This was accomplished through the establishment
of small clinics in local schools or through affiliations with com-
munity health centers.More recently,we developed the ElderSmile
program, which focused on the oral health care needs of older
adults.The patient care component of that program includes visits
to what we term prevention sites,often located in senior centers.We
provide both oral hygiene education and screenings for attendees.
Individuals in need of services are then referred to a number of
community treatment centers that specialize in providing dental
services to older adults.
Dr.Moskowitz: What role do your alumni play in the overall
workings of the dental college?
Dean Lamster:The alumni play a very important role.First,a
significant percentage of our full-time, part-time and volunteer
faculty are alumni of the predoctoral and/or postdoctoral pro-
grams.Second,the alumni support the school in a variety of ways
besides serving on the faculty.For example,they participate in our
continuing education program as lecturers and presenters; they
contribute to our annual fund;and we are soon to announce a new
capital campaign.They have helped the campaign get off to a fine
start. In addition, I am continuously impressed with the accom-
plishments of our alumni.We have started to feature these individ-
uals and their accomplishments in our alumni magazine Primus
and our alumni newsletter Primusnotes.
Dr. Moskowitz: What makes Columbia University College of
Dental Medicine different from other dental institutions?
Dean Lamster:We have redefined the predoctoral curriculum
on the basis of three tenets. First, our dental students take their
basic science courses with the students at the College of Physicians
and Surgeons.Second,we stress the critical importance of postdoc-
toral education, be that a general practice residency or an AEGD
program or a specialty program. In fact, over the past few years,
more than 97% of our students have continued their education.
Third,we have made dual-degree training an important part of our
Dental school at Columbia University, in New York City, awarded first dental degree
in 1922, six years after it opened.
18 NYSDJ • APRIL 2007
curriculum.These offerings include DDS/MPH and DDS/MBA pro-
grams, as well as a newly introduced DDS/MA in education with
our Teacher’s College. This is intended for those interested in an
academic career.We have also just started our first DDS/PhD pro-
gram,in Bioinformatics.Similar changes are being introduced into
the postdoctoral/residency programs.
In addition,our place within the Columbia University Medical
Center makes us one of only a few dental schools that are truly inte-
grated into their health sciences campus.As you know, we do not
have our own building,but,rather,we have floors within the Medical
Center. This promotes collaboration with the medicine, public
health and nursing programs on a variety of levels.
Dr. Moskowitz: Dental schools tend to be somewhat insular
with respect to other parts of their universities.What is the rela-
tionship between the College of Dental Medicine and other colleges
within Columbia University?
Dean Lamster:That is not the case at Columbia.While we and
the other CUMC schools are physically separated from the 116th
Street campus,we are clearly part of Columbia,and the ties between
the campuses continue to grow. For example, one of our faculty
members is the co-chair of the Columbia University Diversity
Council for the professional schools.Our faculty is also involved in
the new CTSA grants for clinical research funded by NIH;and one of
our junior faculty received a K12 award through that program. In
addition, we have a robust research program with Biomedical
Engineering,which is located primarily on the 116th Street campus.
There are other examples,but you can see the pattern.
Dr.Moskowitz: How are you preparing your predoctoral stu-
dents and postdoctoral residents to cope with an increasingly com-
plex health care environment?
Dean Lamster:We feel the environment here at the college is
the best teacher.That is,we see dentistry as an integral part of the
health sciences environment,and our predoctoral students,post-
doctoral students and hospital residents learn from the outset
that they are treating a patient and not just a set of dental prob-
lems. We also have developed a “curricular map,” which defines
the four years of the curriculum into basic,behavioral and clini-
cal tracks so the students can see how these three components fit
together. There is also time in the curriculum for discussion of
larger issues facing the dental profession,including access to care,
dental health care services for older adults and understanding the
current role of the profession, as well as the possibilities for the
future. Just today, I heard a report on our efforts to introduce
smoking cessation into the predoctoral program. This program
has made great strides in the past three years,and we believe that
our graduates will incorporate this aspect of primary health care
into their practices.
We are fortunate to attract an excellent group ofdental students,
postdoctoral students and residents.They are well read and socially
conscious when they come to us.We try to nurture that attitude.
Dr. Moskowitz: Funding is always a critical issue in private
academic institutions.How does Columbia manage this situation?
Dean Lamster: The economics of a private dental school are
challenging.We are structured so that we are not too dependent on
any one source or revenue. Tuition accounts for only one-third of
our budget, with clinical income accounting for 40%, and 25% is
everything else, including research, extramural programs and
fund-raising activities.Each school within Columbia budgets in a
similar manner. We capture all of our income, including tuition,
clinic fees and all direct and indirect costs associated with grants.
In turn, we pay a “common cost” to both the University and the
Dean Lamster presides over one of regularly scheduled lunch meetings with small groups of second-year predoctoral students. From left: students Helen Park and
Charles Yau; Dean Lamster; student Phillip Mann; NYSDJ Editor Elliott Moskowitz.
NYSDJ • APRIL 2007 19
Dr. Moskowitz: How do you balance allocating resources for
scholarly academic matters and clinical areas?
Dean Lamster: This is one of the most challenging parts of
the job.There are many good ways to spend money—new clinical
faculty, adding additional research faculty, construction of new
facilities,a new clinic information system,to name a few.I rely on
the faculty,and,in particular,the senior faculty,to help guide these
decisions.Over the past few years,we have added to the clinical fac-
ulty and recruited new research faculty who are engaged in collab-
orative research across the Medical Center and the University. In
addition, we have built new research laboratories and renovated
some clinical areas.We are now constructing a new faculty practice
on the Medical Center campus.Our next task is to renovate one of
our main clinical floors.So,I guess the response to your question is
Dr. Moskowitz: Where do ethics fit into the curriculum of
your Columbia students? What special challenges do you see in this
Dean Lamster: Maintaining ethical standards is a challenge
for the professions and for society in general.We recently revamped
our ethics program and now include instruction in ethics in all four
years ofthe curriculum.In fact,ethical behavior is addressed at ori-
entation for the new first-year students and is reinforced during
that week with the White Coat Ceremony.We have also established
an Ethics Committee for the College,with representation from the
senior and junior full-time faculty, the part-time faculty and the
Dr. Moskowitz: Can you tell me if there are any significant
problems in attracting our younger colleagues to either full-time or
part-time faculty positions? And if so,why?
Dean Lamster: In the past few years,we have increased the
full-time faculty by 10%. For the most part, these have been
recent graduates who have completed their specialty training or
completed a general practice residency. They are engaged in
teaching, research and clinical care. These are terrific people
who are joining the full-time faculty for the right reasons.They
enjoy teaching and do it well,and are enthusiastic about an aca-
demic career. Many, but not all, are Columbians. I believe we
have opened our students’eyes to the advantages of an academ-
ic career, in part by offering dual degree programs—we now
even have a DDS/MA joint degree program with the Teacher’s
College. I would like to see more young graduates joining the
Dr.Moskowitz:What would be some incentives for motivating
our colleagues to return to their alma mater as either part-time or
Dean Lamster: There are many reasons to join the volun-
teer faculty.First,as we know,the dental profession is attracting
excellent students. It is rewarding to be involved in their educa-
tion.Second,serving on the volunteer faculty provides opportu-
nities for professional interaction that may not be available to the
full-time clinician. Third, it is the right thing to do. Dental
schools need volunteer faculty. Members of our profession have
realized many terrific advantages as a result of their education.
We should be giving back so our dental schools remain strong
Dr. Moskowitz: Academic institutions and the American
Dental Association have not always worked harmoniously.How can
each support the other’s efforts?
Dean Lamster: I agree that the dental schools and the ADA
have not always worked well together.If one steps back to examine
the situation, there are many reasons why we should work well
together.We are educating the future members of the ADA,and we
can do more if we work together to address problems faced by the
profession.We have, however, developed a good working relation-
ship with the New York State Dental Association. The four dental
schools in New York—Columbia, NYU, SUNY Buffalo and SUNY
Stony Brook—along with the Eastman Dental Center at the
University of Rochester,a graduate dental institution,work togeth-
er on projects of mutual interest through the New York State
Academic Dental Centers group.We often work with NYSDA, and
we have found that we have common goals.A mutual respect has
developed,and I anticipate that this collaboration will continue to
expand in the future.
Dr.Moskowitz:I want to thank you for allowing The NYSDJto
interview you.You have provided us with valuable and interesting
insight into the educational mission of Columbia University and the
challenges of being dean of such a unique academic institution. ■
College of Dental Medicine, on 168th Street, is positioned within Columbia
University Medical Center. Mix of patients seen at College reflects its urban setting.
20 NYSDJ • APRIL 2007
The purpose of this study was to determine the extent of bac-
terial contamination of toothbrushes after use and the efficacy
of chlorhexidine and Listerine in decontaminating tooth-
brushes. The effectiveness of covering a toothbrush head
with a plastic cap in preventing contamination was also eval-
uated. It was found that 70% of the used toothbrushes were
heavily contaminated with different pathogenic microorgan-
isms. Use of a cap leads to growth of opportunistic microor-
ganisms like Pseudomonas aeruginosa, which may cause
infection in the oral cavity. Overnight immersion of a tooth-
brush in chlorhexidine gluconate (0.2%) was found to be
highly effective in preventing such microbial contamination.
THE USE OF ORAL CLEANING INSTRUMENTS,such as a tooth-
brush and dental floss, is essential for removing dental plaque, a
contributor to dental caries and periodontitis. Although various
types of toothbrushes and methods of toothbrushing are
described, procedures required for maintaining their cleanliness
are addressed infrequently.
The concept that toothbrushes are contaminated after use was pro-
posed as early as 1920 by Cobb,1who implicated the contaminated
toothbrush as a cause of repeated infections of the mouth.
Microorganisms can gain entry into a toothbrush from the oral
cavity or from the external environment,such as contaminated fin-
gers, aerosols from toilet flushing and bacteria present in moist,
humid conditions found in the bathroom.
Various studies1-6have reported contamination of toothbrush-
es with microorganisms and have recommended methods of
decontamination.However,no studies have been conducted to find
out the effectiveness of covering the toothbrush head with a plastic
cap in reducing/preventing contamina-
tion, as claimed by various toothbrush
manufacturers. Also, literature is scarce
on the effectiveness of Listerine, a com-
monly used mouthwash in decontaminat-
Therefore,the present study was con-
ducted to determine the level of contami-
nation in used toothbrushes that were
kept open and toothbrushes whose heads
were covered with a plastic cap (Figure 1).
Further, the effectiveness of chlorhexi-
dine and Listerine in decontaminating
used toothbrushes was evaluated.
Bacterial Contamination and Decontamination
of Toothbrushes after Use
Abhishek Mehta,B.D.S.;Peter Simon Sequeira,M.D.S.;Gopalkrishna Bhat,Ph.D.
Figure 1. Different tooth-
brushes tested for contam-
Material and Methods
For the present study, the subjects selected were students from a
hostel,so the environmental conditions were similar.Students who
had open carious lesions, severe gingivitis and throat infections
were excluded from the study.Ten individuals,aged 24 to 27,were
selected, and written informed consents were obtained. Two
unused toothbrushes (control) were cultured to check for any
microbial growth in packed toothbrushes before starting the study.
The study was conducted in three phases.In all three phases,
each lasting one week, subjects were provided with a
brand new toothbrush and were instructed to brush
with it twice daily and rinse it in running tap water for
at least 30 seconds.The toothpaste used by all the sub-
jects was the same.
In the first phase,subjects were instructed to keep
their toothbrushes in the open air for drying after use.
In the second phase,retrieved brushes were immersed
in either a 0.2% solution of chlorhexidine gluconate
(ICPA Health Products, India) or Listerine (Pfizer, Ltd., USA)
mouthwash for 12 hours by the investigator.
In the third phase,a new toothbrush,whose head
was covered with a plastic cap, was given.Along with
the instructions given in the previous phases,subjects
were told to keep the toothbrush head covered with a
plastic cap after every use.
Used toothbrushes were recovered after one week
in each phase and were transported in separate sterile
test tubes with a cotton plug for microbiological analy-
sis.The handle of the toothbrush was disinfected with
a surgical spirit and the head part was immersed in 10
ml of phosphate buffered saline (PBS) and vortexed for
five minutes to dislodge the bacteria. Serial 10-fold
dilutions were made and 10 µl was spread on a blood
agar plate.The inoculated plates were incubated at 370
for 24 hours.Colony count was determined and bacte-
ria were defined by standard procedures.7PBS (0.1 ml)
was inoculated into 10 ml of tryptic soy broth and
incubated at 370
oC for 24 hours and observed for any
In the first phase, bacterial contamination was
observed in 7 of the 10 tested toothbrushes. Staphy-
lococcus aureus, Viridans streptococci, S. epidermidis
and Acinetobacter spp were isolated (count >10 5 cfu /
ml) (Table 1).
In the second phase,immersion ofused toothbrush-
es (n=5) in chlorhexidine gluconate (0.2%) could kill
bacteria.Listerine was found to be less effective,as two of
the five brushes showed microbial growth (Table 2).
In the third phase, where a plastic cap-covered toothbrush was
given, 7 out of 10 toothbrushes showed microbial contamination.
Pseudomonas aeruginosa and Klebsiella spp were isolated from six
toothbrushes and one toothbrush, respectively (Table 3). None of
the packed toothbrushes (control) showed microbial growth.
Toothbrushes can get contaminated easily during their use.Reten-
tion of moisture and the presence of organic matter that has come
NYSDJ • APRIL 2007 21
T A B L E 3
Bacterial Contamination of Toothbrushes with Cap
Serial No. of ToothbrushBacterial Contamination Bacteria
T A B L E 1
Bacterial Contamination of Toothbrushes after Use
Acinetobacter spp, S. aureus, Viridans streptococci
Acinetobacter spp, S. aureus, Viridans streptococci
Acinetobacter spp, S. epidermidis
Acinetobacter spp, S. aureus
Acinetobacter spp, S. aureus
Acinetobacter spp, S. aureus
Acinetobacter spp, S. aureus
T A B L E 2
Effect of Antiseptics on Decontamination of Toothbrushes
Serial No. of
Treatment with ChlorhexidineTreatment with Listerine
from the mouth may promote growth of microorganisms on the
toothbrush bristles. Such contamination may lead to colonization
of microorganisms in the mouth and possibly infection. It is also
possible that contamination of toothbrushes can occur through
In the present study, microbial contamination was seen in 7
out of 10 toothbrushes (70%), whereas some previous studies
found microbes on all of the tested toothbrushes.2-5Predominant
microorganisms isolated were Acinetobacter spp, S. aureus, S. epi-
dermidis andViridans streptococci. This is in agreement with most
similar studies.2-4The bacteria were present in count >10 5 cfu / ml,
which is the infective dose for many bacteria.A previous study also
could show similar rates of bacterial contamination in toothbrush-
es after use.3
In the present study,chlorhexidine was found to be effective in
disinfecting contaminated toothbrushes. These results are consis-
tent with previous reports.2-4However,one of the previous studies
showed that Listerine was more effective.1The higher efficacy of
chlorhexidine could be the result of the extended spectrum of
action. Also, it is relatively non-toxic, odorless and is commonly
used as a mouthwash.These properties may make chlorhexidine a
good choice for disinfection of contaminated toothbrushes.
Before commencement of the study, two packed test tooth-
22 NYSDJ • APRIL 2007
brushes were cultured to check for the presence of any microorgan-
isms.No microbial growth was reported from either of the brushes.
This shows that contamination came from the external environment.
We found no clinical studies reporting levels of microbial con-
tamination of toothbrushes whose heads can be covered with plas-
tic caps.In our study,we found that the use of a plastic cap leads to
the growth of microorganisms like Pseudomonas aeruginosa, a
gram negative aerobe and opportunistic pathogen.Therefore,it is
not advisable to cover a toothbrush head with a plastic cap.Use of
a cap may help retention of moisture that promotes growth of P.
1.Caudry SD,Klitorinos A,Chan ECS.Contaminated toothbrushes and their disinfection.
J Can Dent Assoc 1995;61:511-15.
2. Suma Sogi HP,Subbareddy VV,Shashi Kiran ND.Contamination of toothbrush at differ-
ent time intervals and effectiveness of various disinfecting solutions in reducing the
contamination of toothbrush.J Ind Soc Pedo Prev Dent 2002;20:81-85.
3.Bhat SS, Hedge KS, George RM. Microbial contamination of toothbrushes and their
decontamination.J Ind Soc Pedo Prev Dent 2003;21:108-112.
4. Filho PN,Macari S,Faria G,Assed S,Ito IY.Microbial contamination oftoothbrushes and
their decontamination.Paediatric Dent 2000;22:381-4.
5.Taji SS, Rogers AH. The microbial contamination of toothbrushes. A pilot study. Aust
Dent J 1998;43:128-30.
6.Kozai K,Iwai T,Miura K.Residual contamination of toothbrushes by microorganisms.J
Dent Child 1989;56:201-4.
7.Collee JG, Fraser AG, Marmion BP, Simmons AS. Mackey and McCartney. Practical
Medical Microbiology.14th Edition.New York:Churchill Livingstone.1996.
24 NYSDJ • APRIL 2007
A simplified technique for recording maxillomandibular
relations in complete dentures is described. This tech-
nique enables the practitioner to construct a mandibular
occlusal mini-rim directly in the mouth, to adjust it to the
required vertical dimension and to record the maxillo-
mandibular relations during a single appointment. The
mandibular record is formed with wax, used to hold the
occlusal vertical dimension anteriorly, and impression
plaster, to record the centric relation posteriorly.
THE ACCURACY OF maxillomandibular relations is of utmost
importance in the construction of complete dentures. The use of
such dentures is highly dependent upon a correct centric relation
record,1especially during the first post-insertion months.2
Several methods have been described to record maxillo-
mandibular relations for the fabrication of complete dentures.
These include the use of extraoral and intraoral3tracing devices
(Gothic arch), which require additional clinical time, complicated
instrumentation and a high level of skill. They also include the
swallowing procedure, using the soft wax (cones) recording as
described by different authors.4,5However,some authors have ques-
tioned the validity of the swallowing procedure in determining the
reference position in the sagittal plane for the maxillomandibular
relationships of complete dentures.6
Of these techniques,the direct interocclusal records using the
occlusal rims (wax or plastic modeling impression compound) on
record bases remains the most popular technique,7even though it
still needs considerable clinical time to adjust the height of the
occlusal rims to match the desired vertical height of the face.
Several materials have been used to record maxillomandibular
relations in edentulous patients,but impression plaster has gained
in popularity because of its accuracy and repeatability.8,9,10
This technique consists ofpreparing the record bases (Formatray,Kerr
USA, Romulus, MI) with the maxillary occlusal rim only prior to the
appointment. The height and orientation of the maxillary rim
should be adjusted in the mouth as per the conventional methods
(that is,the occlusal plane parallel to the camper plane).
The vertical dimension measurements should be performed
according to the preferred methods—the phonetic “emma”and the
respiratory methods are typically used. The occlusal vertical
dimension (OVD) will be the difference between the rest vertical
dimension (RVD) and the interocclusal rest space.
The next step should consist of lubricating the maxillary rim
with petroleum jelly and putting a drop of wax on the middle of the
SIMPLIFIED METHOD FOR RECORDING
Maxillomandibular Relations in Complete Dentures
NYSDJ • APRIL 2007 25
posterior border of the maxillary rim to indicate the position of the
tip of the tongue during closure in centric relation.
A deeply softened wax wafer,in wet heat preferably (Cavex Set Up
regular modeling wax, Cavex Holland B.V., Haarlem, the Netherlands), should
then be prepared and fixed in the anterior region of the mandibu-
lar base using a hot spatula (Figure 1).However,in extreme angle
Class II jaw relationship cases,the mandibular mini-rim would be
extended to the first premolar region for better stability of the
occlusal rims during the recording.
Both record bases should be inserted in the mouth and the
mandibular occlusal mini-rim arranged in such a way that its
direction closely meets the maxillary rim.The patient should then
be asked to put the tip of his or her tongue on the drop of wax sit-
uated on the posterior border of the maxillary base, according to
the Schuyler technique.11
In the meantime,the practitioner’s left hand should be invert-
ed,the thumb and index finger introduced between the maxillary
rim and the mandibular record base posteriorly to hold the bases
steady and against the ridges.The patient should be asked to close
gently while his or her chin is held between the thumb and the
index finger ofthe practitioner’s right hand (Figure 2).The purpose
is to gently guide the closure movement.During closure,the fingers
of the left hand should slide out progressively12to clear the way for
the closing mandible, which should close until the height that is
judged correct for the vertical dimension is reached. The closing
movement ofthe mandible should be stopped,and the height ofthe
face should be checked with a ruler or a caliper. The mandibular
wax mini-rim should be rubbed with the thumb of the right hand
to adapt it against the maxillary rim. The patient should then be
asked to further close his or her mandible in case it falls short ofthe
calculated dimension;otherwise,the softened wax is rearranged to
meet the calculated height.
Next,the mandibular base should be retrieved from the mouth
and the excess wax trimmed,guided by the imprint of the maxil-
lary rim on the mandibular mini-rim. The mandibular mini-rim,
which should then be chilled in cold water, serves to hold the
mandible at the desired vertical height.
With the record bases back in the mouth in closing position,
three vertical lines should be scratched,one in the midline and two
laterally, on the maxillary and the mandibular rims. This enables
the practitioner to control and guide the centric relation recording
later on (Figure 3). Two non-parallel V-shaped notches should be
cut on the maxillary rim in the molar region in preparation for the
index with the recording material.
While the maxillary rim is in the mouth,fast-setting impres-
sion plaster (Xanthano, Heraeus-Kulzer, Dormagen, Germany) should be
mixed to a creamy blend and spread,slightly in excess occlusally,on
Figure 1. Wax wafer in anterior region of mandibular base.
Figure 2. Closure of mandible stopped at desired vertical height.
Figure 3. Occlusal rims in mouth, with vertical control lines.
the posterior portions of the mandibular record base.The mandi-
bular base should be put inside the mouth and held in place with
the fingers ofthe left hand,placed intraorally.The patient should be
asked to close his or her jaw slowly,with the tip of the tongue on the
posterior border of the maxillary base. The movement should be
guided gently by the practitioner through the chin and into centric
relation.The closure would stop as the mandibular mini-rim con-
tacts the maxillary rim in the already set position.The continuity of
the vertical lines would prove the correct position (Figure 4).
The latter position should be kept unchanged until the setting
of the plaster.
Before the plaster sets, the cheeks of the patient should be
massaged gently to make sure the plaster has spread evenly against
the maxillary rim.As the final setting of the plaster (heat reaction)
is completed,both bases should be retrieved from the mouth that is
26 NYSDJ • APRIL 2007
fixed together. If there are doubts about the recording, separate
rims should be kept and retried in the mouth to make sure that the
plaster index fits the upper notches perfectly at closure.
After setting the height of the vertical dimension and adjusting the
mandibular mini-rim,the patient should be asked to close slowly in
centric relation, as described earlier, until the mandibular rim
touches the maxillary rim. The patient should hold his or her
mandible lightly in that position.
Meanwhile,a fast-setting impression plaster should be mixed,
charged into a 20 cc plastic syringe (Pronto Siringa,Artsana S.P.A.,Como,
Italy) and injected into the posterior region,on the buccal aspect of
the mandibular base.It should be built up until it reaches the max-
illary rim (Figure 5). The cheeks should be gently massaged to
make sure that the plaster has spread all over the maxillary rim.
The plaster has to set before retrieving the record from the mouth.
The application of this alternative method is easier,especially
for the practitioner who is not familiar with the manipulation of
The advantages of the simplified method over the classical method
are described below.
The rapidity of the technique reduces considerably the time needed
for the recording. In the conventional technique, the mandibular
occlusal rim is constructed outside the mouth to an arbitrary height
and adjusted to contact evenly the maxillary rim to meet the height
of the occlusal vertical dimension already calculated. This proce-
dure will be achieved with many limited readjustments of the
occlusal surface ofthe mandibular rim to attain the hiatus-free con-
tact between the rims.Certainly,the occlusal rims need to be tested
in the mouth after every readjustment to assess the progress of the
procedure.In addition,the risk of deviation of the mandible due to
arising posterior prematurities is always possible with the conven-
tional technique,especially for the inexperienced practitioner.
By contrast,when using the simplified technique,the mandi-
bular anterior mini-rim is constructed directly in the mouth devoid
of the posterior portions of the occlusal rim and adjusted easily to
the required height with a single maneuver.The posterior regions
will be filled later by the impression plaster record.
The results of the new method are reliable because the risks of
deviation of the mandible and displacement of the soft tissues
under the record bases13are significantly reduced. This is mostly
because the properties of the impression plaster,which is fluid dur-
ing the first stage of mixing,do not present any resistance for clo-
sure during the recording of the centric relation.The pressure will
Figure 4. Interocclusal recording in mouth with impression plaster record.
Figure 5. Alternative method: injection of impression plaster between maxillary
rim and mandibular record base.
NYSDJ • APRIL 2007 27
be minimal and evenly distributed on both sides of the arch.
Once it is set,the hard and unyielding nature of the plaster will
keep the stability of the centric record in contrast to other record-
ing materials (wax, zinc oxide bite registration paste or plastic
modeling impression compound).
The application ofthe new method is relatively simple and does not
require special skills.
Finally, according to this technique, the maxillomandibular
relations are recorded with two different materials best fit for each
component of these relations: wax for the occlusal vertical dimen-
sion and impression plaster for the centric relation.
A simplified method for recording the maxillomandibular relations
in complete dentures is presented.This method,which is based on
the conventional techniques of investigation of the vertical dimen-
sion and the centric relation,offers the advantages of time,reliabil-
ity and simplicity over previously described techniques. ■
1. Fenlon MR,SherrifM,Walter JD.Association between the accuracy ofthe intermaxillary
relations and complete denture usage.J Prosthet Dent 1999 May;81:520-525.
2.Dervis E.The influence ofthe accuracy ofthe intermaxillary relations on the use ofcom-
plete dentures:a clinical evaluation.J of Oral Rehabil 2004;31:35-41.
3. Langer A, Michman J. Intraoral technique for recording vertical horizontal maxillo-
mandibular relations in complete dentures.J Prosthet Dent 1969;21:599-606.
4. Hakim-Abdel AM.The swallowing position as a centric relation record.J Prosthet Dent
5.Ismail YH, George WA. The consistency of the swallowing technique in determining
occlusal vertical relation in edentulous patients.J Prosthet Dent 1968;19:230-236.
6.Millet C,Jeannin C,Vincent B,Malquarti G.Report on the determination of occlusal ver-
tical dimension and centric relation using swallowing in edentulous patients. J Oral
7.Jaggers JH,Javid NS,Colaizzi FA.Complete denture curriculum survey of dental schools
in the United States.J Prosthet Dent 1985;53:736-739.
8.Urstein M,Fitzig S,Moskona D,Cardash HS.A clinical evaluation of materials used in
registering interjaw relationships.J.Prosthet Dent 1991;65:372-377.
9.Frazier QZ,Wesley RC,Lutes MR,et al.The relative repeatability of plaster interocclusal
eccentric records for articulator adjustment in construction of complete dentures. J
Prosthet Dent 1971;26:456-67.
10. Müller J,Götz G,Hörz W,Kraft E.Study of the accuracy of different recording materials.
J Prosthet Dent 1990;63:41-46.
11. Schuyler Ch.Intraoral method of establishing maxillomandibular relation.JADA 1932;
12. Hickey JC, Zarb GA, Bolender CL. Boucher’s Prosthodontic Treatment for Edentulous
Patients.9th Ed.St Louis:Mosby.1985:288-290.
13. Hemphill CD,Parker ML,Regli CP.Effects of uneven occlusal contact when registering
maxillomandibular relations.J Prosthet Dent 1972;28:357-359.
28 NYSDJ • APRIL 2007
This study was done to analyze the effect of different sur-
faces and different surface applications on the bonding
strength of porcelain repair material and to compare these
factors with one another. Three different substructures of
10 mm diameter and 4 mm thickness were used for the
repair surface: metal, metal on porcelain and porcelain.
The surfaces of half of the samples were roughened with
an air abrasion tool; the surfaces of the other half were
treated with a diamond bur. The specimens were ultrason-
ically cleaned in distilled water. A silane coupling agent
and a bonding agent were applied to the surfaces of all
the samples. Resin composite was applied to each spec-
imen. All specimens were stored in distilled water for 24
hours before being thermocycled. After thermocycling,
specimens were stored in distilled water for an additional
seven days before being subjected to a shear load.
The highest bonding strength was observed in the
samples with a metal substructure, the surfaces of which
were prepared with an air abrasion tool; the lowest bond-
ing strength was observed in the samples with a metal
substructure, the surfaces of which were prepared with a
diamond bur. When different substructures were examined
in terms of bonding strength, the highest bonding strength
was statistically observed in metal-on-porcelain substruc-
tures, and the lowest bonding strength was observed in
the porcelain substructure. When they were examined in
terms of surface processes, the highest bonding strength
was statistically observed in the samples whose surfaces
were prepared with an air abrasion tool, and the lowest
bonding strength was observed in the samples whose sur-
faces were prepared with a diamond bur.
PORCELAIN-FUSED-TO-METAL CROWNS are widely accepted
and used in clinical practice. However, they occasionally demon-
strate fracture of the brittle ceramic veneer.Failure resulting from
porcelain fracture has been reported to range from 2.3% to 8%.1-3
The cause of clinical fracture of veneering porcelain on ceramometal
crowns is multifactorial.Lack of proper framework support for the
Effect of Different Surfaces and Surface Applications
on Bonding Strength of Porcelain Repair Material
Zeynep Duymus Yesil,D.D.S.,Ph.D.;Serpil Karaoglanoglu,D.D.S.,Ph.D.;
Nilgün Akgül,D.D.S.,Ph.D.;Nur Ozdabak,Dr.Med.Dent.;Nurcan Ozakar Ilday,Med.Dent.
porcelain, intraceramic defects or parafunctional occlusion can
cause this inconvenient problem.4
Ideally,remake of the restoration is desirable,but is not always
feasible.The ability to perform an intraoral repair can be of great
benefit to the patient.5However,for the repair to withstand func-
tional loads,the bond between the repair material and remaining
restoration must be strong and durable.6
Three conditions are suggested for repair of porcelain frac-
tures:1.fracture in porcelain only with no metal exposure; 2.frac-
ture with both porcelain and metal exposed; and 3. fracture with
substantial metal exposure.7Various methods have been intro-
duced to repair fractured porcelain with composite.8-11Mechanical
roughing of porcelain surfaces with a coarse diamond bur has
improved repair strengths.12,13Sandblasting with aluminum oxide
is another method of surface roughing.7And porcelain can also be
etched with hydrofluoric (HF) acid or acidulated phosphate fluo-
ride gel to facilitate micromechanical retention of the composite.14-16
Until recently,composite repair of fractured porcelain achieved
little clinical success.Intraoral repair of fractured porcelain tradi-
tionally relied on mechanical roughening of the fractured surface,
followed by application of a silane coupling agent to enhance the
resin to porcelain bond.17
If a small part of the porcelain is missing, it might be a rea-
sonable solution to repair it intraorally with a light-curing compos-
ite resin.A large fracture of porcelain can also be repaired by the
same technique,but the result will never be as durable or esthetic
as the original restoration.18
This study was done to analyze the effect of different surfaces
and different surface applications on the bonding strength of
porcelain repair material and to compare these factors with one
Materials and Methods
A total of 42 cylindrical specimens were fabricated:14 from porcelain
(Ceramco, Burlington NJ,Weybridge UKKT 15 2S, USA); 14 from a Ni-Cr alloy
(Wiron 99,Bego,Bremen,Germany);and 14 from a Ni-Cr alloy and porcelain.
Fabrication of the specimens was as follows:
● Porcelain specimens. Porcelain was condensed in a split
brass mold (1.0 cm diameter and 0.4 cm thickness) with
Modisol separating agent (Vident). Condensed cylinders were
placed on a platinum foil sagger tray and fired at 940
vacuum in a calibrated porcelain furnace (Ugin/Dentaire [Elips],
● Porcelain and metal specimens.Inlay wax cylinders (1.0 cm
diameter;half of the cylinders 0.4 cm thickness,and the other
half 0.2 cm thickness) were invested and cast with the use of
Ni-Cr alloy.The metal cylinders were air abraded with 50 µm
aluminum oxide.The opaque was applied to the side with the
thinner section surfaces and the porcelain was condensed.The
metal and porcelain surface was finished flat with a laboratory
medium-grit sintered diamond bur.
● Metal specimens. Inlay wax was flowed into a silicone mold
(1.0 cm diameter and 0.4 cm thick). The wax cylinder was
invested and cast with the use of a Ni-Cr alloy. The cylinders
were cleaned in an ultrasonic unit in distilled water (Figure 1).
Each of the substrates was embedded in a phenolic ring
(Buehler Ltd,Lake Bluff,IL) with polymethyl methacrylate resin (De Trey
RR,Dentsply,England).Metal,metal on porcelain and porcelain sample
groups were divided into two equal-numbers groups of 14 samples
each.The surfaces ofhalfofthe samples (seven metals,seven metal
on porcelains and seven porcelains) were air abraded with 50 µm
aluminum oxide particles for 15 seconds with an intraoral sand-
blasting device (Prepstar, Danville Engineering, Danville, USA), rinsed and
dried.The surfaces of the other half of the samples were roughened
with a coarse diamond bur (No. 520.4, Abrasive Technologies, Columbus,
Ohio), and each material to be tested was bonded to the prepared
porcelain by following the manufacturer’s directions. The speci-
mens were ultrasonically cleaned in distilled water for 10 minutes.
A silane coupling agent and a bonding agent were applied to
the mid parts of all the samples in accordance with the recommen-
dations of the manufacturers. The adhesives were used in accor-
dance with the manufacturer.A silane coupling agent (Clearfil Se Bond
Primer; Kuraray, Ltd., J Morita USA, Inc., Tustin, Calif.) and bonding agent
(Clearfil Se Bond; Kuraray, Ltd., J Morita USA, Inc., Tustin, Calif.) were applied
to the complete samples (metal,metal on porcelain and porcelain)
and allowed to air dry.The adhesives were used in accordance with
the manufacturer. Resin composite (Valux Plus 3M ESPE, Seefeld,
Germany) was applied to each specimen according to the manufac-
turer’s instruction using a Teflon split matrix,3.5 mm diameter and
2 mm thick (Ultradent, South Jordan, Utah).Resin composite was poly-
merized with 40-second visible light applications (Elipar II,3M ESPE,
Seefeld,Germany).After the matrix was removed,an additional 40 sec-
onds of visible light was applied.
All specimens were stored in 37
before being thermocycled between 5
with a 30-second dwell time.After thermocycling,specimens were
stored in 37
being subjected to a shear load.
The Hounsfield testing machine (Hounsfield Test Equipment
Company, HTE 37 Fullerton Road, Croydon, England), with a 0.5 cm/min
crosshead speed and chisel apparatus,was used to direct a parallel
shearing force as close as possible to the resin/substrate interface.
oC distilled water for 24 hours
oC and 55
oC for 300 cycles
oC distilled water for an additional seven days before
NYSDJ • APRIL 2007 29
Figure 1. Metal, porcelain and metal-porcelain specimens.
30 NYSDJ • APRIL 2007
The shear load in newtons at the point of failure was noted and
force was calculated in megapascals (MPa).
An analysis of variance (ANOVA) was applied to the data.
Mean and standard deviations were calculated.
The results of the variance analysis used to evaluate the data are
shown in Table 1.
It was statistically determined that the type of substructure
used for repair, the surface application and interactions are not
important (p> 0.05).
The mean and standard deviation results of the data
obtained are shown in Table 2.The highest bonding strength was
observed in the samples with metal substructure,the surfaces of
which were prepared with air abrasion (11.99 MPa); then came
the samples with metal-on-porcelain substructure,the surfaces of
which were roughened with air abrasion (11.30 MPa).The lowest
bonding strength was observed in the samples with metal sub-
structure, the surfaces of which were prepared with a diamond
bur (9.35 MPa).
When different substructures were examined in terms of
bonding strength, the highest bonding strength was statistically
observed in the metal-on-porcelain substructures (11.27 MPa) and
the lowest bonding strength was observed in the porcelain sub-
structure (10.03 MPa) (Table 3). When they were examined in
terms of surface processes, the highest bonding strength was sta-
tistically observed in the samples whose surfaces were prepared
with air abrasion,and the lowest bonding strength was observed in
the samples whose surfaces were prepared with a diamond bur.
This study examined the shear bond strengths of composite mate-
rial used for repair in three representative situations:fracture with-
in porcelain; fracture within porcelain with exposure of some
ceramic alloy; and fracture with complete porcelain delamination
and exposure of a large section of alloy.When the fracture occurs
with metal exposure,the repair is more problematic.
Traditionally, attempts to bond resin to metal have involved
roughening the metal to provide mechanical retention of the resin.
One easy method of enhancing bond strength is roughening the
surface by air abrasion with aluminum oxide, thereby increasing
the surface area for bonding and decreasing surface tension.19
High composite alloy bonds have been reported with base
metal alloys treated with sandblasting.20,21A previous study report-
ed that the alumina content ofbase alloys increased up to 37% after
sandblasting, and ultrasonic cleaning resulted in only minor
removal of the embedded alumina.22Sandblasting the base alloy
surface that resulted in the surface containing a significant amount
of alumina particles,which affects bond strength,has been report-
ed.23Porcelain surface sandblasted with alumina resulted in micro-
mechanical roughening and covering with small alumina parti-
Results of Analysis of Variance
Surface Treatments (ST)
ST X Substrate
Mean and Standard Deviation Results of Results Obtained
NYSDJ • APRIL 2007 31
cles.24The reported bond strengths of the sandblasted porcelain
surface ranged from 9 to 17 MPa.25
The present study yielded results within the limits mentioned
by the above researchers.
Chung and Hwang6reported a significant increase in bond
strength of composite-to-base alloy when the surface was air
abraded with aluminum oxide.Suliman et al25noted no significant
differences between diamond roughening, air abrasion and
hydrofloric acid treatment.Unglazed porcelain surfaces have been
shown to contribute to stronger composite-porcelain bonding,10
and the application of silane,regardless of prior surface treatment,
has consistently raised bond strengths in laboratory studies.14,26
Kupiec et al27found that hydrofluoric acid treatment enhanced
bond strength,especially when used with a silane agent.Similarly,
Stangel et al14demonstrated that etching porcelain with hydrofloric
acid significantly contributed to increased bond strength of the
Roughening with air abrasion and diamond bur was used as
the surface application in the present study. As hydrofluoric acid
was present in the bond used;it was applied to all the samples.
Mechanical alteration of a porcelain surface is more important
than agents that promote chemical bonding of composite resin to
porcelain.28With the above researchers’views in mind,silane,a cou-
pling agent, and a bonding agent were applied to the surfaces to
which the composite would be applied following the mechanical
According to Anusavice,29an infinite number of fracture paths
ofthe veneer porcelain can occur.Clinically,porcelain fracture can be
seen with no exposure of the metal substrate or with complete deve-
neering ofporcelain with extensive metal exposure.Repairs made on
multiple substrates may behave differently than those made only on
a ceramic surface.Previous studies have primarily examined repairs
made solely to a porcelain or alloy substrate.4,10,30-32Few have tested
bond strengths to a combined surface.6Bond strength values
depended on the system used,with the strongest bonds to porcelain
resulting in cohesive failure in the porcelain substrate.11,33
Chung and Hwang,6in their study,in which they applied dif-
ferent composite resins and their bonds to different substrates,
determined that the highest degree of bonding strength was in the
samples with the metal substrates.
It was found that the best bond between the fractured surface
and the repair composite resin was obtained with a porcelain
instead of metal surface.8,18Because the success of the adherence
depends on the amount of remaining porcelain surface,it was pro-
posed to extend the bonding surface of the fractured porcelain to
improve the bond strength of the repair material.34
32 NYSDJ • APRIL 2007
There is little information on the bond strength of porcelain repair
materials to the metal porcelain combined surface.6When the
repaired surfaces were compared in terms of the bonding strength,
the highest bonding strength was determined in the subjects with
metal-on-porcelain substructure. This result is in harmony with
the findings of the above-mentioned researchers.
Research on porcelain repair has included shear, tensile and
three-point loading. The porcelain-resin interface has also been
subjected to fatigue loads.30The concept of fatigue testing is applic-
able to brittle ceramic materials;29but when such testing is applied
to the porcelain-resin interface, large standard deviations suggest
an abnormally distributed population because some specimens do
not fail.30A shear test was chosen for this study because multiple
substrates were used.In addition,anterior restorations are subject-
ed primarily to shear stresses, and the shear test is considered
appropriate for quantifying the strength of porcelain repairs.35
The use of thermocycling is variable in the literature. Most
studies using thermocycling have reported that bond strengths are
reduced by thermocycling.11,36A common finding among many of
these studies was a reduction in shear bond strength after pro-
longed water storage and/or thermocycling.2,10,11,30-32The effects of
moisture, thermal stress and fatigue on bond strength have been
Since the effect of thermocycling was not examined in our
study, we could not form a control group. So thermocycling was
applied in the way recommended in the literature.3,10,11,30,31,32,36
It was statistically determined that the type of substructure, the
surface application and the interactions were not important. The
highest bonding strength was observed in the samples with metal
substructure,the surfaces ofwhich were prepared with air abrasion.
The lowest bonding strength was observed in the samples with
metal substructure,the surfaces of which were prepared with a dia-
When different substructures were examined in terms ofbond-
ing strength,the highest bonding strength was statistically observed
in metal-on-porcelain substructures, and the lowest bonding
strength was observed in the porcelain substructure. When they
were examined in terms of surface processes,the highest bonding
strength was statistically observed in the samples whose surfaces
were prepared with air abrasion, and the lowest bonding strength
was observed in the samples whose surfaces were prepared with a
diamond bur. ■
1.Libby G,Arcuri MR,LaVelle WE,Hebl L.Longevity of fixed partial dentures. J Prosthet
2.Strub JR, Stiffler S, Schärer P.Causes of failure following oral rehabilitation: biological
versus technical factors.Quintessence Int 1988;19:215-222.
3.Coornaert J,Adriaens P,De Boever J.Long-term clinical study ofporcelain-fused-to-gold
restorations.J Prosthet Dent 1984;51:338-342.
4.Bello JA,Myers ML,Graser GN,Jarvis RH.Bond strength and microleakage of porcelain
repair materials.J Prosthet Dent 1985;54:788-791.
Haselton DR,Diaz-Arnold AM,Dunne JT.Shear bond strengths of 2 intraoral porcelain
repair systems to porcelain or metal substrates.J Prosthet Dent 2001;86:526-531.
Chung KH,Hwang YC.Bonding strengths of porcelain repair systems with various sur-
face treatments.J Prosthet Dent 1997;78:267-274.
Bertolotti RL, Lacy AM, Watanabe LG. Adhesive monomers for porcelain repair. Int J
Beck DA,Janus DE,Douglas HB.Shear bond strength ofcomposite resin porcelain repair
materials bonded to metal and porcelain.J Prosthet Dent 1990;64:529-533.
Bailey JH. Porcelain-to-composite bond strengths using four organosilane materials. J
Prosthet Dent 1989;61:174-177.
10. Diaz-Arnold AM,Schneider RL,Aquilino SA.Bond strength of intraoral porcelain repair
materials.J Prosthet Dent 1989;61:305-309.
11. Pratt RC,Burgess JO,Schwarts RS,Smith JH.Evaluation of bond strength of six porce-
lain repair systems.J Prosthet Dent 1989;62:11-13.
12. Jochen DG, Caputo AA. Composite resin repair of porcelain denture teeth. J Prosthet
13. Ferrando JM,Graser GN,Tallents RH,Jarvis RH.Tensile strength and microleakage of
porcelain repair materials.J Prosthet Dent 1983;50:44-50.
14. Stangel I,Nathanson D,Hsu CS.Shear strength of the composite bond to etched porce-
lain.J Dent Res 1987;66:1460-1465.
15. Tylka DF,Stewart GP.Comparison of acidulated phosphate fluoride gel and hydrofluoric
acid etchants for porcelain-composite repair.J Prosthet 1994;72:121-127.
16. Della Bona A,van Noort R.Shear vs.tensile bond strength of resin composite bonded to
ceramic.J Dent Res 1995;74:1591-1596.
17. Council on dental materials, instruments and equipment, porcelain repair materials. J
Am Dent Assoc 1991;122:124-130.
18. Hirschfeld Z, Rehany A. Esthetic repair of porcelain in a complete-mouth reconstruc-
tion:a case report.Quintessence Int 1991;22:945-947.
19. Swift EJ Jr.New adhesive resins.A status report for the American Journal of Dentistry.
Am J Dent 1989;2:258-260.
20. Aquilono SA,Diaz-Arnold AM,Priotrowski TJ.Tensile fatigue limits of prosthodontics
adhesives.J Dent Res 1991;70:208-210.
21. Chang JC,Powers JM,Hart D.Bond strength of composite to alloy treated with bonding
systems.J Prosthodont 1993;2:110-114.
22. Kern M, Thompson VP. Sandblasting and silica coating of dental alloys: volume loss,
morphology,and changes in the surface composition.Dent Mater 1993;9:155-161.
23. Diaz-Arnold A,Keller JC,Wightman JP,Williams VD.Bond strength and surface charac-
terization of a Ni- Cr- Be alloy.Dent Mater 1996;12:58-63.
24. Kern M, Thompson VP. Sandblasting and silica coating of a glass-infiltrated alumina
ceramic: volume loss,morphology,and changes in the surface composition.J Prosthet
25. Suliman AH,Swift EJ Jr,Perdigao J.Effects of surface treatment and bonding agents on
bond strength of composite resin to porcelain.J Prosthet Dent 1993;70:118-120.
26. Hayakawa T,Horie K,Aida M,Kanaya H,Kobayashi T,Murato Y.The influence of surface
conditions and silane agents on the bond of resin to dental porcelain. Dent Mater
27. Kupiec KA,Wuertz KM,Burkmeier WW,Wilwerding TM.Evaluation ofporcelain surface
treatments and agents for composite- to- porcelain repair.J Prosthet Dent 1996;76:119-
28. Thurmond JW,Burkmeier WW,Wilwerding TM.Effect of porcelain surface treatments
on bond strength of composite bonded to porcelain.J Prosthet Dent 1994;72:355-359.
29. Anusavice KJ.Phillips’science of dental materials.10th Ed.Philadelphia:WB Saunders
30. Llobell A, Nicholls JI, Kois JC, Daly CH. Fatigue life of porcelain repair systems. Int J
31. Appeldoorn RE,Wilwerding TM,Burkmeier WW.Bond strength of composite resin to
porcelain with newer generation of porcelain repair systems.J Prosthet Dent 1993;70:6-
32. Cooley RL,Tseng EY,Evans JG.Evaluation ofa 4-META porcelain repair systems.J Esthet
33. Wolf DM,Powers JM,O’Keefe KL.Bond strength of composite to porcelain treated with
new porcelain repair agents.Dent Mater 1992;8:158-161.
34. Berksun S,Kedici PS,Saglam S.Repair of fractured porcelain restorations with compos-
ite bonded porcelain laminate contours.J Prosthet Dent 1993;69:457-458.
35. Leibrock A,Degenhart M,Behr M,Rosentritt M,Handel G.In vitro study of the effect of
thermo- and load-cycling on the bond strength of porcelain repair systems. J Oral
36. Newburg R,Pameijer CH.Composite resins bonded to porcelain with silane solution.J
Am Dent Assoc 1978;96:288-291.
Alport syndrome (AS) represents a genetic cause of renal
failure that affects about 1 in 5,000 Americans. In cases of
AS, the problem resides on the X chromosome. Specific
mutations to the gene cause defects in one of several sub-
units of Type IV collagen. Accumulation of collagen types
V and VI, with subsequent abnormalities in the permeabil-
ity and sclerosis of the kidney, leads to renal failure.
Renal failure causes severe bone disease since the
kidney processes vitamin D, which is necessary for calci-
um absorption from the intestine. Therefore, in a patient
with chronic renal disease, vitamin D is not produced,
resulting in a decrease in intestinal absorption of calcium
and subsequent lower serum calcium levels. Furthermore,
the decreased phosphate excretion by the kidney leads to
elevation of plasma phosphate, which increases the
amounts of parathyroid hormone required to move calcium
from bone (secondary hyperparathyroidism) to maintain
plasma calcium at a constant level and preserve an
appropriate calcium-phosphorous ratio.
We have described AS, reviewed the pathogenesis
and presented an interesting extreme case with numerous
34 NYSDJ • APRIL 2007
ALSO KNOWN AS hereditary deafness nephropathy, Alport syn-
drome (AS) presents as a genetic cause ofkidney failure and afflicts
about 1 in 5,000 Americans.It also affects the cochlea and the eye.
AS is identified by its presence on the X chromosome,specifi-
cally,the gene COL 4A5.Mutations to the gene cause defects in one
of several subunits of Type IV collagen,specifically,? 3- ? 4- and
? 5- chains, which may be absent. As a compensatory response,
there is an accumulation of collagen types V and VI in the base-
ment membrane of the glomerulus. Subsequent abnormalities in
the permeability and sclerosis of the kidney tissue will lead to renal
A group of hereditary diseases characterized by thrombocy-
topenia,renal disease,cataracts and deafness are called Alport-like
syndromes because they are clinically similar. But the genetic
mutations linked to this group of disorders are different from those
seen in AS.2,3There are two genetic types:autosomal dominant (1%
of the cases), and autosomal recessive (14% of the cases). The X-
linked AS constitutes 85% of the cases of Alport and Alport-like
syndromes.The condition is more severe in males than females,but
there is no racial predilection.4
Approximately one million nephrons are present in each normal
kidney,but since chronic renal failure (CRF) is characterized by a
loss of nephrons, AS patients exhibit progressive destruction of
them.To compensate for the destroyed renal tissue,hypertrophy of
the remaining healthy kidney proceeds to maintain the glomerular
filtration rate and continues until the renal reserve has been
exhausted.But the kidney hypertrophy leads to increased glomeru-
lar capillary pressure,which damages the capillaries and represents
yet another cause of renal dysfunction.
Report of a Case with Severe Maxillofacial Manifestations
Kurt Friedman,D.D.S.,M.S.;Ines Velez,D.D.S.,M.S.
The involvement of the glomerulus in patients with AS produces
hematuria as an earliest manifestation.Proteinuria and hyperten-
sion develop in adulthood, with severity increasing with age.
Initially,the clinical findings are unremarkable,but with time,pro-
gressive renal failure,manifested by edema,chronic anemia,severe
bone alterations and hypertension,is observed.5
Hearing defects, including bilateral high frequency hearing
loss,become apparent by late childhood,before the onset of renal
failure. Some patients with AS also exhibit ocular manifestations,
such as lenticonus and retinopathy, which manifest at the time of
kidney failure.Proliferation of the smooth muscle of the esophagus
and the tracheobronchial system is seen in some cases,6as is men-
Establishing a Diagnosis
The diagnosis of AS is based upon family history,physical exami-
nation, immunohistochemical analysis of basement membrane
Type IV collagen—using skin or kidney tissue—and electron micro-
scopic renal biopsy analysis. Genetic testing is available for X-
Since there is no specific treatment that can cure AS,a kidney
transplant is usually needed. Unfortunately, the immune system
may react against the normal collagen of the new kidney,destroy-
ing the transplant and leading to end stage renal failure.8
Renal failure causes severe bone disease since the kidney
processes vitamin D, which is necessary for calcium absorption
from the intestine.Therefore,in a patient with chronic renal disease,
vitamin D is not produced, resulting in a decrease in intestinal
absorption of calcium and subsequent lower serum calcium levels.
Furthermore,the decreased phosphate excretion by the kidney leads
to an elevation ofplasma phosphate,which increases the amounts of
NYSDJ • APRIL 2007 35
Figure 1. Clinical view. Facial deformity is evident.
Figure 2. Alveolar ridge and gingival enlargement. Diastemas.
Figure 3. CT scan; axial view. Craniofacial lesions.
Since there is no specific treatment that can
cure AS,a kidney transplant is usually needed.
Unfortunately,the immune system may react
against the normal collagen of the new
kidney,destroying the transplant and leading
to end stage renal failure.8
parathyroid hormone required to move calcium from bone (sec-
ondary hyperparathyroidism) to maintain plasma calcium at a con-
stant level and preserve an appropriate calcium-phosphorous ratio.
The turnover of the bone increases, as does the number of bone
remodeling centers;and if calcification of osteoid is inhibited,bone
disease becomes severe with the possibility of pathologic fracture.
The result is osteomalacia with generalized loss of the lamina dura
being seen as an early manifestation of the condition.A decrease in
trabecular density is observed,and brown tumors (sometimes mul-
tiple) of hyperparathyroidism usually develop. Osteomalacic bone
may show mineralization and osteosclerosis later.
Anemia is always present,mainly as a result ofthe decreased pro-
duction ofred blood cells by the bone marrow.This is due to the inabil-
ity of the kidneys to secrete erythropoietin, the hormone needed to
stimulate normal bone marrow to produce red cells.Blood loss,result-
ing from the malfunction of platelets in patients suffering from ure-
mia,and hemolysis,seen in advanced renal failure,are also factors that
contribute to the severe anemia observed in those cases.Furthermore,
the normal life span oferythrocytes is about four months.But in renal
failure patients, the life of the red blood cells is reduced due to the
chemical effect ofthe uremia.In addition,the accumulation ofuremic
toxins may play a role in depressing bone marrow function.
A person with severe anemia tries to compensate for this con-
dition by increasing bone marrow tissue,and,subsequently,blood
cell production. It can be done easily by somebody with normal
bone marrow, but in renal failure, the bone marrow’s capacity to
compensate is decreased,even though bone marrow tissue may be
generated in sites such as the mandible and skull.
The effects of CRF on bone are primarily due to secondary
hyperparathyroidism.The condition that develops in these patients
36 NYSDJ • APRIL 2007
is called osteitis fibrosa cystica,and it results from the degeneration
of the multiple brown tumors. One clinical manifestation of this
entity is the striking enlargement of the jaws.9Bone deformity and
widening of bone plates also occur as a result of the body’s efforts
to compensate for anemia.This combination of anemia,secondary
hyperparathyroidism, osteomalacia, osteitis fibrosa cystica and
osteosclerosis leads to the alteration of bone in end stage renal dis-
A 29-year-old black female was referred to the oral and maxillo-
facial surgeon because of severe bleeding of the gingiva.Medical
history showed a previously confirmed diagnosis of Alport syn-
drome.The patient developed progressive loss of renal function,
and a kidney transplant was necessary.Failure of two renal trans-
plants and end stage renal disease led to dialysis as the only
Examination revealed a terminally ill black female patient
exhibiting severe cosmetic and functional deformity. Significant
observations included painless, bilateral and symmetrical severe
swelling of the maxilla with involvement of the orbital floor,
extreme bilateral enlargement of the mandible and multiple
diastemas. The bone expansion caused swelling and distortion of
the face and subsequent widening of the alveolar ridge,as well as
tooth displacement and tooth mobility, impaired mastication and
speech difficulties. Fibrosis and bleeding of the gingiva and very
poor oral hygiene were factors also recorded.
The radiographs and CT scan exhibited generalized expansive,
mixed,radiolucent and radioopaque areas over the entire craniofa-
cial skeleton.Most of the radiographic lesions were completely dif-
Figure 4. CT scan; sagital view. Craniofacial lesions.
Figure 5. CT scan; tri-dimensional view. Surface rendering. Generalized lesions.
Loss of cortical bone (secondary hyperparathyroidism) is evident.
NYSDJ • APRIL 2007 37
fuse and some areas exhibited ground glass appearance.The skull
bones showed radiopaque areas and radiolucent lesions with
widening of bone plates. The radiolucent lesions may have repre-
sented bone marrow defects or brown tumors.
The severe bone deformity present in this case may have
been caused by a combination of compensatory anemia lesions,
secondary hyperparathyroidism, osteomalacia, osteitis fibrosa
cystica and posterior hypercalcification. The gingival bleeding
noticed in this patient was due to malfunction of the platelets and
decrease in bone marrow cell production, usually present in
patients with an accumulation of uremic toxins and exacerbated
by poor oral hygiene.
We have described Alport syndrome, reviewed the pathogenesis
and presented an extreme case with numerous craniofacial mani-
festations. Besides extreme bone deformities, patients may show
fractures, epistaxis, gingival bleeding, anemia, lenticonus and
retinopathy.Other associated maxillofacial problems include hear-
ing and speech difficulties and malocclusion.
AS is a condition initiated by a genetic alteration of Type IV
collagen,followed by subsequent abnormalities in the permeability
of the kidney,resulting in renal failure.In advanced cases,a combi-
nation of secondary hyperparathyroidism, osteomalacia, osteitis
fibrosa cystica and osteosclerosis leads to dramatic bone changes.
Renal failure also causes anemia, the result of different mecha-
nisms, such as lack of erythropoietin, decreased life span of ery-
throcytes, blood loss produced by platelet malfunction and toxic
depression of bone marrow function.A compensatory increase in
bone marrow production may also lead to maxillary, mandibular
and skull lytic lesions and enlargement.
The pathogenesis of the mechanisms previously described
may be enough to explain the severe bone changes observed in this
1. Gross O,Netzer KO,Lambrecht R,Seibold S,Weber M.Meta-analysis of genotype-phe-
notype correlation in X-linked Alport syndrome:impact on clinical counseling.Nephrol
Dial Transplant 2002;17:1218-1227.
2.Epstein CJ, Sahud MA, Piel CF, Goodman JR, Bernfield MR, Kushner JH, Ablin AR.
Hereditary macrothrombocytopenia,nephritis and deafness.Am J Med 1972;52:299-310.
3. Rocca B,Laghi F,Zini G,Maggiano N,Landolfi R.Brit J Haemat 1993;85:423-426.
4.Longo I,Porcedda P,Mari F et al.COL 4A3/COL 4A4 mutations from familial hematuria
to autosomal dominant or recessive Alport syndrome.Kidney Int 2002;61(6):1947-1956.
5.Mothes H,Heidet L,Arrondel C,Richter KK,et al.Alport syndrome associated with dif-
fuse leiomyomatosis:COL4A5-COL 4A6 deletion associated with a mild form of Alport
nephropathy.Nephrol Dial Transplant 2002;17:70-74.
6. Dische FE, Weston MJ, Parsons V. Abnormally thin glomerular basement membranes
associated with hematuria,proteinuria or renal failure in adults.Am J Nephrol 1985;5:
7.Meloni I,Vitelli F, Pucci L et al.Alport syndrome and mental retardation: clinical and
genetic dissection of the contiguous gene deletion syndrome in Xq 22.3 J Med Genet
8.Byrne MC,Budisavljevic MN,Fan Z,et al.Renal transplant in patients with Alport’s syn-
drome.Am J Kidney Dis 2002;39(4):769-775.
9.Gavalda C, Bagan JV, Scully C, et al.Renal Hemodialysis Patients.Oral, salivary, dental
and periodontal findings in 105 adult cases.Oral Dis 1999;5:292-302.
38 NYSDJ • APRIL 2007
Surgical soft tissue exposure of im-
pacted teeth can now be performed
with little to no discomfort and excel-
lent postoperative healing. This paper
focuses on the techniques used in
performing this procedure.
THE IMPLEMENTATION of lasers in den-
tistry has given dentists a completely new
instrument in their armamentarium. In
recent years,lasers have proven to be an inte-
gral part of many dental practices.1-3Use of
the laser allows the general clinician to per-
form a variety of procedures without the
adjunctive use of local anesthesia,alleviating
patient anxiety, while increasing the clini-
cian’s own capabilities to perform procedures
they might otherwise have referred to a spe-
cialist.4Laser use has also facilitated specialty
practice by allowing the specialist to perform
many soft tissue surgical procedures more
expeditiously and with excellent postopera-
tive healing. It also has eliminated the need
for local anesthesia in many cases.1,5,6
The Er,Cr:YSGG dental laser can accom-
plish these tasks by using a wavelength of
2,780 nm to energize water particles deliv-
ered at the fiber optic tip through various
ratios of water and air to cut both hard and
soft tissue effectively without causing
microcrazing in the enamel matrix.7,8With
respect to soft tissue,it can use the existing
hydration of the oral soft tissue to perform
its task.7,9This interaction at the tissue sur-
face with energized water particles is
termed “hydrokinetic”energy.6With use of
the Er,Cr:YSGG laser,the clinician is able to
achieve exceptional results in both the
operating procedure and in postoperative
An 8-year-old child presented to the dental
clinic with both maxillary central incisors
impacted in the soft tissue. Because of the
age of the child and the possible sequelae of
the laterals drifting mesially and future
orthodontic complications,the decision was
made to surgically expose the teeth.7The
laser technique was employed using a T4 tip
and three consecutive settings to first
obtain laser anesthesia. One of the many
benefits of using the laser is being able to
forgo the traditional injection anesthetic in
Laser Exposure of Unerupted Teeth
Ali Asgari,D.D.S.;Barry L.Jacobson,D.M.D.;Manisha Mehta,D.M.D.;John L.Pfail,D.D.S.
performing the procedure. Although not
effective in every situation,with proper case
selection and repeated practice, the laser
can yield excellent results in obtaining laser
The first setting of 0.25 W with 10%
air and no water was used while slowly out-
lining the area of exposure.The proper dis-
tance can be gauged by evaluating the
white chalky outline as the laser begins to
excise the tissue.Excessive darkening ofthe
tissue should not be seen this early on in
the procedure.1-5The setting was then
increased to 0.5 W with 10% air and no
water and the same outline followed.Third,
0.75 W was used with 10% air and no
water. This is done to achieve anesthesia
and to serve as a guideline for outlining the
area to be surgically exposed.8,10
The tissue begins to darken as the
power increases and the cutting becomes
more aggressive. Once anesthesia is estab-
lished, the soft tissue settings of the laser
are used at 1.5 W with 7% water and 11%
air.3,4The tip is changed to the G4 tip,which
allows more precise cutting of the tissue.
The water is not being used as the cutting
agent in the soft tissue procedures because
the tissue is already hydrated.11Thus, the
Figure 1a. Preoperative.
Figure 1b. Laser at 0.5W.
Figure 1c. Laser at 0.75W.
Figure 1d. Laser at soft tissue set-
ting; G4 tip.
Figure 2h. Setting at 2.0 W.
Figure 2g. Setting at 0.75W.
Figure 2f. Setting at 0.5W.
Figure 2c. Soft tissue settings.
Figure 2d. Postoperative view.
Figure 2e. Setting at 0.25W.
NYSDJ • APRIL 2007 39
water and air settings are decreased from
the hard tissue setting to act mainly as a
cooling mechanism as the laser cuts soft
tissue.8,9The G4 tip is moved back and forth
along the exposure line already delineated
by the T4 tip. Deeper cuts are made until
the soft tissue impeding the eruption of the
central incisors is removed.11
The patient was seen one week postop-
eratively and reported no discomfort.3-5The
central incisors began erupting into their
A second case presented with a similar situ-
ation of an impacted left central incisor.The
8-year-old child with a soft tissue impacted
maxillary left central incisor was brought in
for routine care.The child displayed an oth-
erwise normal eruption pattern, and the
tooth was treatment planned for a surgical
exposure. Along with functional challenges
to mastication,the soft tissue-impacted cen-
tral incisor was also causing the patient emo-
tional distress,as he was being teased by his
peers.The decision was made to expose the
incisor to facilitate its eruption into proper
alignment,treat the patient’s chief complaint
and correct his dental malocclusion.
A procedural protocol similar to the
one used in Case One was followed,with cer-
tain modifications to the laser settings.The
procedure began again by obtaining soft tis-
sue anesthesia. In this situation, we main-
tained the same wattage settings,but the air
was increased by 4%.The procedure began
with the settings at 0.25 W with 14% air and
no water, slowly outlining the area of the
exposure.The setting was then increased to
0.5 W with 14% air and no water, and the
same outline was followed. Finally, 0.75 W
was used with 14% air and no water,thereby
completing the laser anesthesia technique.
The laser was focused and defocused,accord-
ing to the patient’s response.Once proper
soft tissue anesthesia was obtained,the set-
ting was switched to the soft tissue ablation
settings and gentle removal ofthe tissue was
The G4 tip was used in a continuous
sweeping motion, and the proper distance
was established by gauging the color
change in the tissue to a darker appear-
ance.Enough tissue was removed until the
crown of the tooth was exposed. Once the
crown became apparent, cutting was
ceased to prevent damage to the underlying
Figure 1e. One week postoperative.
Figure 2a. Preop.
Figure 2b. Operative.
40 NYSDJ • APRIL 2007
ed the need for local anesthesia in many
cases. This is of particular importance in
pediatric dentistry because it not only does
away with the anxiety and fear associated
with receiving an injection,it also removes
the risk of post-anesthetic complications,
such as the child accidentally injuring him-
The reasons for the numbing effect of
the laser have only been postulated at this
point to result from its transient anesthetic
effect, since the laser is not in continuous
contact with the tissue.12The pulsation of
the laser allows it to be in contact intermit-
tently in rapid sequence,relieving the pain
stimulus associated with the procedures.
The laser also removes the need for a
scalpel in performing these procedures.
Although a skilled surgeon can use the
scalpel with great accuracy, once an inci-
sion is made, there is no digressing from
the cut.With the laser,the clinician can bet-
ter control how aggressively he or she wants
to be in removing tissue.11,12Therefore, a
less experienced clinician can use the laser
at a lower setting and cut the tissue more
slowly to reach the same result but at a pace
more fitting to his or her comfort level.11,12
This affords orthodontists, for example,
who may not have been trained extensively
in performing these soft tissue exposures,
the opportunity to begin treating cases
such as soft tissue impacted teeth, which
they encounter on a regular basis.7This will
allow them to expand their practice and
have more control over individual cases.
The hemostatic effect of the laser is
also of note.13Compared to the traditional
scalpel and suture method of performing
soft tissue dentistry, the laser greatly
reduces the trauma placed on the tissue,
thereby expediting the healing time and
effect.7,11The laser can cauterize the tissue
as it cuts, greatly reducing the amount of
heme in the field.11,13It also negates the
Subsequent to sufficient tissue removal,the
tooth will be able to erupt into the proper
The third case involves a 10-year-old
female with both permanent central incisors
and a right lateral incisor still not erupted.
The radiograph demonstrated more than
two-thirds root development and possible
impaction of the teeth if the roots contin-
ued to grow without the teeth erupting
through the gingiva. The child presented
with speech difficulties and, based on her
reserved manner in the clinic, psychologi-
cal difficulties, arising from her missing
front teeth.The decision was made to expose
the teeth using the above-mentioned laser
settings.In this case,the patient was expe-
riencing discomfort from the procedure
even with repeated efforts to obtain laser
Local anesthetic of three-quarters of a
Carpule of 3% Carbocaine was used for
anesthesia. It was explained to the parent
that further exposure might be required for
the right lateral incisor because of the
extent of the impaction. Also, an insuffi-
cient amount of space was presented as a
possible complication in allowing the later-
al incisor to erupt into place. It was also
possible that maxillary expansion would be
needed in the future.
Within one week of the procedure,the
central incisors had begun erupting.
The patient was followed up three
months later.The central had erupted com-
pletely. An additional surgical exposure of
tooth #7 was completed and within one
week,the tooth had begun erupting.
The laser offers the clinician a multitude of
advantages in performing soft tissue den-
tistry.11First and foremost,it has eliminat-
Figure 3a. Preop.
Figure 3b. Operative.
Figure 3c. Immediate postop.
Figure 3d. One week postop.
Figure 3e. Three months postop.
The laser offers the clinician a multitude of advantages in perform-
ing soft tissue dentistry.11First and foremost,it has eliminated the
need for local anesthesia in many cases.
NYSDJ • APRIL 2007 41
13. Midda M. The use of lasers in periodontology. Curr
Opin Dent 2 1992:104–108.
14. Shulkin NH.The American dental laser: initial patient
response.Dent Today 1991;10:60-61.
14. Sun G. The role of lasers in cosmetic dentistry. Dent
Clin North Am.2000;44(4):831-50.
15. Rossman JA,Cobb CM. Lasers in periodontal therapy.
Periodontology 2000 1995;9:150–164.
16. Sarver DM,Yanosky M.Principles ofcosmetic dentistry
in orthodontics:part 3.Laser treatment for tooth erup-
tion and soft tissue problems.Am J Orthod Dentofacial
Orthop 2005;in press.
17. Ishikawa I,Sasaki KM,Aoki A,Watanabe H.Effects of
Er:YAG laser on periodontal therapy. J Int Acad
18. Rosenberg SP. The use of erbium,chromium:YSGG
laser in microdentistry.Dent Today 2003;22(6):70-3.
19. Coluzzi DJ. An overview of laser wavelengths used in
dentistry. In: The Dental Clinics of North America.
20. Kutsch, VK. The history of dental lasers. Proceedings
from the World Clinical Laser Institute. August 2003,
21. Passes H, Furman M, Rosenfeld D, Jurim A. A case
study of lasers in cosmetic dentistry.Curr Opin Cosmet
2. Eversole LR, Rizoiu IM. Preliminary investigations on
the utility of an erbium,chromium YSGG Laser.J Calif
Dent Assoc 1995:41-47.
Margolis, F. Point of care. J Canad Dent Assoc 2002;
Eversole LR,et al.Osseous repair subsequent to surgery
with an erbium hydrokinetic laser system.Proceedings,
International Laser Congress,Athens Greece.September
Pick RM,Powell GL.Laser in dentistry.Soft-tissue pro-
cedures.Dent Clin North Am 1993;37(2):281-96.
Flax HD, Radz GM. Closed-flap laser-assisted esthetic
dentistry using Er:YSGG technology.Compend Contin
Educ Dent 2004;25(8):622,626,628-30.
Marx I,Op’t HJ.The Er,Cr:YSGG hydrokinetic laser sys-
tem for dentistry-clinical applications. So Afr Dent J
Colvard, MD, Pick RM. Future direction of lasers in
dental medicine.Curr Opin Periodontol 1993:144–150.
Smith TA, Thompson JA, Lee. Assessing patient pain
during dental laser treatment. J Am Dent Assoc.
10. Sulieman M.An overview of the use of lasers in gener-
al dental practice: 1. Laser physics and tissue interac-
tions.Dent Update 2005;32 (4):228-30,233-4,236.
11. Stabholz A, Zeltser R, Sela M, Peretz B, Moshonov J,
Ziskind D,Stabholz A.The use oflasers in dentistry:prin-
ciples of operation and clinical applications. Compend
Contin Dent Educ 2003;24(12):935-48;quiz 949.
12. Scott A.Use ofan erbium laser in lieu ofretraction cord:
a modern technique.Gen Dent.2005;53 (2):116-9.
need for sutures in many situations and,
as evident in the cases cited here,the post-
operative healing is excellent both in
patient comfort and appearance of the sur-
gical site.7The tissue appears pink, stip-
pled and healthy one week following a
resection of soft tissue and surgical expo-
sure of the teeth.7
What the laser has done for patient
acceptance of cases and patient apprehen-
sion is also significant.4,6,14With use of the
Er,Cr:YSGG laser,a clinician can confident-
ly offer a patient a painless surgical proce-
dure performed in a short amount of time.
This may be a foreign concept to many
patients, but it is the reality of what clini-
cians can provide today.4,6,8,14■
1.Rizoiu IM,Eversole LR,Kimmel AI.Effects of an erbium,
chromium: yttrium, scandium, gallium, garnet laser on
mucocutanous soft tissues.J Perio 2001;72 (9):1178-1182.
42 NYSDJ • APRIL 2007
Pemphigus vulgaris (PV) is traditionally viewed as an
autoimmune disease of the skin, but it almost always
involves the oral cavity. It can be fatal if left untreated and
allowed to progress to advanced stages. Early recognition
and intervention are essential for a favorable prognosis.
Since oral lesions represent an initial manifestation of PV,
dentists are in an ideal position to make an early diagno-
sis and initiate treatment. Here we report a case of PV that
was diagnosed in its earliest stage.
PEMPHIGUS VULGARIS (PV) is a chronic autoimmune, intraep-
ithelial blistering disease.It is a potentially fatal dermatological dis-
order characterized by the production of auto-antibodies directed
against the epithelium.PV is classically viewed as a disease of the
skin,but it almost always affects the oral cavity.1,2In 50% of cases,
the oral cavity represents the initial site of presentation before any
skin or other mucosal lesions arise.3,4Dentists are,therefore,in the
unique position to make the preliminary diagnosis and initiate
early treatment of this life-threatening disease.
Here,we report a case of PV that was detected within weeks of
the initial onset.The significance ofthis report rests on the fact that
the presenting clinical lesions were extremely modest and repre-
sentative of an early form of PV.
A 58-year-old female presented to the Salivary Gland Center at
Columbia University College of Dental Medicine with a three-week
history of burning sensations in the oral cavity.Her medical histo-
ry was not significant, and the patient was in good health.At the
time of examination,she was not taking any medications.
The intraoral examination revealed what appeared to be a
small, 2 mm x 4 mm, healing ulcer with an erythematous border
situated on the attached gingiva in the mandibular premolar area
(Figure 1).A second small, 2 mm x 3 mm, irregular mild erythe-
matous lesion was found in the mucosal fold of the left retromolar
area (Figure 2). Extraorally, there were no signs of any skin or
An excisional biopsy of the lesion in the premolar area was
performed.Sloughing of the mucosal tissue was noted during the
biopsy procedure.Because this desquamation aroused a suspicion
of PV,a specimen of the adjacent normal tissue was also harvested
and subjected to a direct immunofluorescence (DIF) study.
The histological examination revealed fragments of stratified
squamous epithelium exhibiting a suprabasilar-intraepithelial split
(Figure 3).Acantholysis and strips ofepithelium demonstrating com-
plete detachment from the connective tissues were also observed.The
DIF study was positive and revealed IgG and C3 deposits in the
intercellular spaces throughout the epithelium.Both the histologi-
cal and DIF results were consistent with a diagnosis of PV.
Pemphigus can exist alone,or it may be associated with thymoma,
myasthenia gravis, lupus erythematous, bullous pemphigoid and
some neoplasias.5,6 Pemphigus has an incidence of about 0.1 to 0.5
per 100,000 in the U.S.7,8It affects all races, but the condition is
more common among Ashkenazi Jews and people of Mediterranean
descent.9Both sexes are equally involved,usually in the fifth to sixth
decades of life. Rare cases in children and the elderly have also
Early Manifestation of Pemphigus Vulgaris
A CASE REPORT
Keith Da Silva;Louis Mandel,D.D.S.
NYSDJ • APRIL 2007 43
Pemphigus includes PV,pemphigus foliaceus and paraneoplastic
pemphigus, but PV is the most common and represents 80% of
PV is a tissue-specific autoimmune disease.It is characterized
by the deposition of an IgG autoantibody against the desmosomal
glycoproteins,desmoglein-1 and desmoglein-3,which are found on
the surface of keratinocytes and act as glue holding the epithelium
together.11The circulating IgG antibodies interfere with cell-to-cell
adhesion and lead to flaccid blister formation and skin separation.1
The initial causative factors for the production of these autoan-
tibodies are unknown,but they may be linked to the presence of a
human leukocyte antigen (HLA) complex.12PV can also be induced
by certain medications,such as captopril and penicillamine.13,14
Oral lesions of PV can develop up to four to six months before
skin lesions appear.15The most common site in the oral cavity is the
buccal or labial mucosa,with the gingiva and palate being less fre-
quently involved. The patient often complains of a persistent sore
throat or burning of the mouth.Clinically,multiple large,flat,vari-
able-sized blisters with a red or white necrotic slough and sur-
rounding erythema are characteristically seen.1The lesions are
superficial and will rupture easily,leaving painful coalesced ulcers
that involve large areas of the oral mucosa. These large denuded
areas become susceptible to secondary infection.Gingival involve-
ment may take the form of desquamative gingivitis. Pressure
applied to an adjacent area will form a new blister (Nikolsky’s sign),
an important diagnostic aid for several bullous diseases.1
PV must be distinguished from other bullous lesions,such as
erosive lichen planus, bullous pemphigoid, erythema multiforme,
dermatitis herpetiformis, epidermolysis bullosa and Darier’s dis-
ease.Definitive diagnosis of PV is dependent upon biopsy results.
For histological examination, it is best to obtain tissue samples
from intact vesicles of recent onset.When PV is suspected,adjacent
normal tissue is required for DIF study.
The classic histological feature seen in PV is acantholysis, or
loss of cell-to-cell contact in the epithelial layer.In PV,intercellular
edema occurs within the epithelium, resulting in widening of the
intercellular spaces and formation of suprabasilar blisters.16The
pathognomonic suspended acantholytic epithelial cells (Tzanck
cells) within the suprabasilar blister can also be detected with exfo-
liative cytology (Tzanck smear).1
DIF is also necessary for diagnosis of PV.Such a diagnosis is
best obtained by submitting a specimen from an area immediately
adjacent to the suspected lesion.DIF reveals deposits of linear IgG
and C3 on the surface of keratinocytes within the intercellular
spaces.17,18Indirect immunofluorescence can also be used to obtain
serum titer values of IgG,which may be proportional to the severi-
ty of the disease.1
Early diagnosis of PV is paramount to successful treatment.In
our case, a modest healing ulcer of unknown etiology was found,
Figure 1. Healing ulcer with erythematous border situated on attached gingiva
Figure 2. Mild erythematous lesion observed in mucosal fold (white arrow).
Figure 3. H&E stain of specimen reveals fragments of stratified squamous epithelium
exhibiting suprabasilar-intraepithelial split. Tzanck cells are indicated by black arrow.
prompting the decision to biopsy.It was only during the biopsy pro-
cedure that the sloughing of tissue was noted and PV suspected.
PV was once associated with a high morbidity rate. However, the
advent of systemic corticosteroids and immunosuppressive therapy
has reduced the mortality rate to below 10%.4,19Treatment of PV is
designed to inhibit production ofthe aggressor antibodies.The initial
treatment involves administering high doses of a systemic corticos-
teroid such as prednisolone.7Once the initial lesion has disappeared,
the dose ofcorticosteroids can be tapered,until a maintenance dose is
achieved. When the initial systemic dose is not sufficient, adjuvant
immunosuppressives, such as cyclophosphamide, azathioprine and
mycophenolate mofetil,are added for their steroid sparing effect.7The
need for high systemic doses of corticosteroids can also be reduced
with the additional use of topical corticosteroids in the form of
mouthrinses or ointments.
When PV is severe and unresponsive to standard corticos-
teroid and oral immunosuppressive agents, pulse therapy with
large doses of intravenous methylprednisone or cyclophos-
phamide may be required.4Plasmapheresis or high-dose intra-
venous immunoglobulin therapies have also been shown to be
44 NYSDJ • APRIL 2007
effective and may be considered as alternatives.4,7,20The required
duration of systemic immunosupression is variable and unclear.
The chances of achieving complete remission are much higher
when the initial presentation is mild and there is an early and rapid
response to treatment.4As in our case,the recognition of an early
lesion and subsequent initiation of treatment resulted in a favor-
Pemphigus vulgaris is a rare autoimmune mucocutaneous blister-
ing disease that can be fatal if left unmanaged.The characteristic
desquamative blistering lesion and the appearance of skin and
other mucosal lesions represent advanced stages of PV.In order to
prevent morbidity and reduce mortality,early recognition and ther-
apeutic intervention are essential.
Since PV has an initial oral manifestation, dentists are in an
ideal position to make an early diagnosis,therefore the need to biop-
sy all suspicious lesions in the oral cavity that may resemble PV. ■
1. Weinberg MA,Insler MS,Campen RB.Mucocutaneous features of autoimmune blister-
ing diseases.Oral Surg Oral Med Oral Path Oral Radiol Endod 1997;84:517-34.
2.Scully C,Challacombe SJ.Pemphigus vulgaris: update on etiopathogenesis,oral mani-
festations and management.Crit Rev Oral Biol Med 2002;13:397-408.
3. Stoopler ET,Sollecito TP,DeRossi SS.Desquamative gingivitis: early presenting symp-
toms mucocutaneous disease.Quint Int 2003;34:582-586.
4.Robinson NA, Yeo JF, Lee YS. Oral pemphigus vulgaris: a case report and literature
update.Ann Acad Med Singapore 2004;33:63-68.
5. Ben Lagha N,Poulesquen V,Roujeau JC,Alantar A,Maman L.Pemphigus vulgaris:a case
based update.J Can Dent Assoc 2005 Oct;71:667-72.
6.Mahajan VK,Sharma NL,Sharma RC,Garg G.Twelve-year clinico-therapeutic experience
in pemphigus:a retrospective study of 54 cases.Int J Dermatol 2005 Oct;44:821-8277.
7.Yeh SW, Sami N, Ahmed R. Treatment of pemphigus vulgaris: current and emerging
options.Am J Clin Dermatol 2005;6;327-242.
8.Fellner MJ,Sapadin AN.Current therapy of pemphigus vulgaris.Mt.Sinai J Med 2001;
9.Thivolet J, Jablonska S. Bullous disorders: from histology to molecular biology. Clin
10. Berger BW,Maler HS,Kantor I.Pemphigus vulgaris in 3 ½-year-old baby.Arch Dermatol
11. Amagai M.Desmoglein as a target in autoimmunity and infection.J Am Acad Dermatol
12. Ahmed AR,Mohimen A,Yunis EJ,Mirza NM,Kumar V,Beutner EH,Alper CA.Linkage
of pemphigus vulgaris antibody to the major histocompatibility complex in healthy rel-
atives of patients.J Exp Med 1993;177:419-24.
13. Kaplan RP,Potter TS,Fox JN.Drug-induced pemphigus related to angiotensin-convert-
ing enzyme inhibitors.J Am Acad Dermatol 1992;26:364-645.
14. Korman NJ, Eyre RW, Zone J, Stanley JR. Drug-induced pemphigus: autoantibodies
directed against the pemphigus antigen complexes are present in penicillamine and
captopril-induced pemphigus.J Invest Dermatol 1991;96:273-6.
15. Siegel MA,Balciunas BA,Kelly M,Serio FG.Diagnosis and management of commonly
occurring oral vesiculoerosive disorders.Cutis 1991;47:39-43.
16. Hashimoto K, Lever WE An electron microscopic study of pemphigus vulgaris of the
mouth and skin with special reference to the intercellular cement. J Invest Dermatol
17. Jordon RE. Direct immunofluorescent studies of pemphigus and bullous pemphigoid.
Arch Dermatol 1971;103:486-90.
18. Kim YH,Geoghegan WD,Jordon RE.Pemphigus immunoglobulin G subclass autoantibodies:
studies ofreactivity with cultured human keratinocytes.J Lab Clin Med 1990;115:324-31.
19. Lever WF,White H.Treatment of pemphigus with corticosteroids:results obtained in 46
patients over a period of 11 years.Arch Dermatol 1963;87:12-26.
20. Ahmed AR,Dahl MV.Consensus statement on the use of intravenous immunoglobulin
therapy in the treatment of autoimmune mucocutaneous blistering diseases. Arch
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46 NYSDJ • APRIL 2007
An accident that can occur during endodontic treatment is
perforation, which adversely affects the prognosis of the
teeth. A restorative material should be easy to use, non-
resorbable, biocompatible, esthetically pleasing, and
should provide a complete seal. Mineral trioxide aggre-
gate (MTA) is a relatively new material that is being used
successfully to repair perforation. The purpose of this
study was to perform a clinical and radiographical evalu-
ation of the success rate of root perforation repairs using
mineral trioxide aggregate. Based upon the results of this
study, MTA is a suitable material for root perforation repair
and can be used confidently.
ONE OF THE EVENTS that occurs during endodontic treatment is
strip and forcal perforation.Ingle1showed that the second greatest
reason for treatment failure was related to root perforation.
However, these operative errors accounted for only 9.62% of the
According to Seltzer’s study,2if the perforated region can be
closed quickly,so that infection and packing do not intervene,there
is a chance for regeneration ofthe periodontium everywhere except
over the perforated region. Therefore, a material with appropriate
seal ability with no cytotoxic effect should be considered.
Variables affecting the long-term prognosis of perforations
include location of the defect relative to the crestal bone; length
of the root trunk; accessibility for repair; size of the defect; pres-
ence or absence of a periodontal communication to the defect;
time lapse between perforation and repair; the sealing ability of
the restorative material; and subjective factors,such as technical
competence of the dentist and the attitude and oral hygiene of
Balla5and Eldeeb6explained that inflammation in the perfo-
rated area may be due to the inadequate sealing ability of the repair
materials. A restorative material should be easy to use, non-
resorbable, biocompatible, esthetically pleasing, and should pro-
vide a complete seal.7
Perforation defects may be repaired by nonsurgical or surgical
techniques.8Surgical alternatives are hemisection,bicuspidization,
root amputation and intentional replantation.The materials com-
monly employed to repair perforations include: cavit,9zinc oxide
eugenol (ZOE),3amalgam,6super-EBA,10tricalcium phosphate,11
calcium hydroxide,12gutta-percha,13IRM14and glass ionomer.15
Mineral trioxide aggregate (MTA) is a material that was intro-
duced in 1993.14,16It is a hydrophilic powder that sets when in con-
tact with moisture.
Clinical and Radiographic Evaluation of
Root Perforation Repair Using MTA
Jamileh Ghoddusi,D.D.S.,M.Sc.;Azadeh Sanaan,D.D.S.;Fatemeh Shahrami,D.D.S.,M.Sc.
NYSDJ • APRIL 2007 47
In 1993, Lee et al14tested amalgam, IRM and MTA for repair of
experimentally created root perforations. The result showed that
the MTA had significantly less leakage than IRM or amalgam.
In 1995, Torabinejad et al17investigated the marginal adapta-
tion ofMTA as a root-end filling material compared with super-EBA
and IRM. Statistical analysis of data comparing gap sizes between
the root-end filling materials and their surrounding dentin shows
that MTA had better adaptation than super-EBA and IRM.
In 1995, another study was done by Torabinejad et al.8They
compared the antibacterial effects of amalgam, ZOE, super-EBA
and MTA on facultative bacteria and seven strict anaerobic bacte-
ria. Results showed that amalgam had no antibacterial effect
against any ofthe bacteria tested in this study.MTA had an antibac-
terial effect on some of the facultative bacteria and no effect on any
of the strict anaerobic bacteria. ZOE and super-EBA pastes had
some antibacterial effects on both types of bacteria tested.
In 1997,Torabinejad et al19examined the periradicular tissue
response ofmonkeys to MTA and amalgam as root-end fillings.The
results showed no periradicular inflammation adjacent to five ofsix
root ends filled with MTA;also,five ofsix root ends filled with MTA
had a complete layer of cementum over the filling.In contrast, all
root ends filled with amalgam showed periradicular inflammation,
and cementum had not formed over the root-end filling material,
although it was present over the cut root end. Based on these
results,MTA was recommended as a root-end filling material.
In 1998, Sluyk et al20evaluated the setting properties and
retention characteristics of MTA when used as a forcation perfora-
tion repair material. The results showed that MTA resisted dis-
placement at 72 h to a significantly greater level than at 24 h.When
slight displacement occurred at 24 h,the material demonstrated the
ability to re-establish resistance to dislodgement from the dentin
wall. The presence of some moisture in the perforation during
placement was advantageous in aiding adaptation of MTA to the
walls of the perforation,but there was no significant difference in
MTA retention when a wet or dry cotton pellet was placed in the
pulp chamber during the setting time.
In 1999,Schwartz et al21presented five cases in which MTA was
used to manage clinical problems. These included vertical root
fracture,apexification,perforation repair and repair ofa restorative
defect.In each case,MTA allowed bone healing and elimination of
clinical symptoms. It allowed the overgrowth of cementum and
periodontal ligament. Because of these results, MTA may be an
ideal material for certain endodontic procedures.
In 2001,Holland et al22observed the healing process of inten-
tional lateral root perforation repaired with MTA. Results showed
no inflammation and deposition of cementum over MTA in the
majority of the specimens.In the 180-day period,sealapex control
groups exhibited chronic inflammation in all the specimens and
slight deposition of cementum over the material in only three cases
of 48 teeth. In conclusion, MTA exhibited better results than the
In 2001 Roda,23in 2002 Joffe,24and in 2003 Hembrough et al25evalu-
ated the clinical success rate of root perforation repair using MTA.
Results showed that MTA sealed the perforation region successfully.
In 2004, the clinical success rate of MTA was evaluated by
Main et al.26They showed that it provides an effective seal perfora-
tion for teeth that would otherwise be compromised.
The purpose of the study described here was to ascertain a
clinical and radiographical evaluation of the success rate of root
perforations using MTA.
Method and Materials
In this clinical trial study, the subjects were people who were
referred to Mashad Dental School with the primary diagnosis of
perforation. After clinical and radiographical examination, the
including criteria were:presence of forcal or strip perforation;loca-
tion of the perforation under the alveolar crest; absence of a large
perforation; no periodontal disease; and presence of mechanical
perforation. Finally,28patients were selected. The results of the
examination were collected from evaluation forms.
The treatment was done in either one or two steps.The teeth
that had been perforated for one week or less were treated by the
one-step treatment,using MTA (Pro Root,Dentsply,Tulsa,OK).Teeth that
had been perforated for more than one week were treated with a
two-step treatment; the first step consisted of using calcium
hydroxide,and in the second step,MTA was used.After treatment
in both groups,a wet cotton pellet was placed over the MTA,and the
teeth were restored.
The treated teeth were followed up after 6 to12 months.These
teeth were evaluated clinically and radiographically to examine the
healing process.Three radiographs were examined for each tooth.
The first radiograph was the preoperative film, exposed before
repair of the perforation defect. The second radiograph was the
film exposed immediately after repair of the perforation.The third
radiograph was the follow-up film taken at least six months after
the repair procedure.
The results were recorded noting the presence or absence of a
periradicular lesion.A lesion was defined as any radiolucency adja-
cent to the repair site that exceeded double the width of a normal
periodontal ligament space.All 28 cases were also clinically evalu-
ated to determine the presence or absence ofa periodontal defect in
the area of the perforation.Periodontal pocket measurements were
noted from the follow-up examination.All evaluations were done
by two endodontists.
Finally, according to the negative or positive response to
the treatment, the teeth were categorized into three groups as
Successful.The periapical or forcal radiolucency was eliminat-
ed or became smaller and the clinical signs were eliminated.
Unsuccessful. The periapical or forcal radiolucency became
larger or remained unchanged and the clinical signs were not
Graph 2: Frequency of Response to Treatment
48 NYSDJ • APRIL 2007
Non-defined. The clinical signs were eliminated but the peri-
apical or forcal radiolucency remained unchanged.
This study was descriptive. The rate of abundance of each group
was described by the graphs. In this study, the patients were
arranged into four groups.The majority of cases fell in the 20-to-
29-age group.The teeth,based on their type,were categorized in six
groups of upper and lower incisors, premolars and molars.
According to the radiographical signs before treatment, 64.3% of
the subjects had radiolucency before treatment, 10.7% were nor-
mal, and 21.4% had widening of PDL. The clinical signs before
treatment are charted in Graph 1.The postoperative radiographic
condition after the 6- to 12-month follow-up period is summarized
in Table 1, which shows that 82.1% of cases were repaired. In all
cases,the clinical signs and symptoms were eliminated.
According to Graph 2,92.9% of cases were placed in the suc-
cessful group.Figures 1-3 demonstrate preoperative,postoperative
and follow-up radiographs of one of the treated cases.
Root perforation is an undesirable accident that can occur at any stage
of root canal therapy. It includes apical, forcal and strip perforation.
Much research has been done on the sealing materials used on perfora-
tions.The factors affecting the repair process include the location ofthe
perforation,the time lapse before obturation ofthe perforation,and the
sealing ability and biocompatibility of the repair materials.3Many
materials have been used to repair perforations,such as IRM,14ZOE,3
cavit,9amalgam,6calcium hydroxide,12super-EBA10and glass ionomer.15
The last recommended material was MTA,which was first used
in 1993.14,16There have been more animal and in vitro investigations
of MTA than human studies of this material.The cervical or forcal
perforations, because of their oral communication, had the worse
prognosis in comparison with apical or middle root perforations.3
The main reason to control perforations is to limit the inflam-
matory process and to promote PDL attachment.Each material or
technique has its own characteristic that should be considered in
clinical use. Based upon the many investigations of perforation
repair that have been done,MTA was introduced as a suitable mate-
rial. The results of this study, in comparison with the results of
other investigations, showed a remarkable increase in positive
prognosis in perforated teeth that were repaired with MTA.
Graph 1: Frequency of Sign and Symptom Before Treatment
Normal Pain & Swelling
T A B L E 1
Frequency of Radiographic Sign After Treatment
Radiography Number Percent
Widening of PDL
Figure 1. Radiograph before treatment
shows radiolucent lesion in furcation.
Figure 2. Radiograph after treatment.
Figure 3. Radiograph one year after
treatment shows healing.
NYSDJ • APRIL 2007 49 Download full-text
In our study,28 teeth in different patients that had had forcal or strip
perforation were selected.Ofthese 28 teeth,26 cases in which clinical
signs and symptoms that appeared before treatment were eliminated
completely and the radiolucency was smaller or repaired completely
were defined as successful.One case had failure in treatment.In this
case,there were no clinical signs or symptoms before and after treat-
ment,but the radiolucent area became larger.In fact,it seems that the
case selection was wrong because the perforation area in this tooth
was so large.Also,one tooth was considered to be a non-defined case
because of the superimposition of anatomic landmarks on the perfo-
ration region.As a result,we could not investigate this area.
Finally,this study showed that MTA is a very suitable material
for root perforation repair and increases the root prognosis signif-
icantly. In 1995, Pitt Ford et al27examined MTA as a perforation
repair material. In this animal study, MTA was compared with
amalgam,and the results showed MTA was a suitable material for
repair ofroot perforations.In 1998,Nakata et al28evaluated the abil-
ity of MTA and amalgam to seal forcal perforations in extracted
human molars using an anaerobic bacterial leakage model. The
results showed that MTA was significantly better than amalgam in
preventing leakage of F.nucleatum in forcal perforations repair.
In 2001,Holland et al22observed the healing process of inten-
tional lateral root perforation repaired with MTA.It was an animal
study and the results introduced MTA as a suitable perforation
repair material,too.In 2002,Weldon et al29longitudinally compared
the ability of MTA and super-EBA to seal forcation perforation.
This study was done on extracted human teeth.In this study,MTA
sealed perforations very well.
In 2004,Main et al26evaluated the clinical success rate of MTA
in root perforation repairs. In this study, 16 cases were examined.
Five were cases of lateral perforation;five were cases of strip perfo-
ration;three were cases offorcal perforation;and three were cases of
apical perforation.In Main’s study,like our study,the teeth had no
periodontal disease. Nine cases had radiolucency and seven cases
had no lesion before treatment.Finally,after the follow-up period,all
cases showed no lesion in the perforation area. In fact, this study
showed the suitability of MTA in sealing root perforations, too. In
2005, Bargholz30suggested a resorbable collagen material for root
perforation repairs.The author claimed that the matrix reconstruct-
ed the outer root shape and facilitated the MTA adaptation.
Conclusion and Suggestions
The results of this study showed that MTA is a suitable material for
root perforation repair and can be used confidently.Therefore,the
prognosis of the perforated teeth that were repaired with MTA
increases significantly.The case selection for perforations repair is
important.The location and size of the perforation,the tooth situ-
ation,the existence or absence of periodontal disease and accessi-
bility to the perforation area are very important in case selection.
Finally, further histological investigations with longer follow-up
periods seem to be necessary. ■
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