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378 Journal of Dental Education ■ Volume 68, Number 3
A Preliminary Study in Using Virtual Reality to
Train Dental Students
Vicki R. LeBlanc, Ph.D.; Alice Urbankova, M.L.L.Dr.; Farhad Hadavi, D.M.D., M.Sc.;
Richard M. Lichtenthal, D.D.S.
Abstract: This study compared virtual reality simulator-enhanced training with laboratory-only practice on the development of
dental technical skills. Sixty-eight students were randomly assigned to practice their skills in either a traditional preclinical
dentistry laboratory or in combination with a virtual reality simulator. The results indicate that students who trained with the
virtual reality simulator between six and ten hours improved significantly more than did the students in the control group from
the first examination of the year to the final examination of the year. These results indicate that the use of virtual reality simula-
tors holds promise for the training of future dentists. Additional research is necessary to determine the ideal implementation of
virtual reality simulators into traditional dentistry curricula.
Dr. LeBlanc is Assistant Professor, University of Toronto, Faculty of Medicine; Dr. Urbankova is Assistant Clinical Professor,
Columbia University School of Oral and Dental Surgery; Dr. Hadavi is Professor, Clinical Dentistry, Columbia University School
of Oral and Dental Surgery; and Dr. Lichtenthal is Benfield Associate Professor and Chair of the Division of Operative Dentistry
and Endodontics, Department of Restorative Dentistry, Columbia University School of Oral and Dental Surgery. Direct corre-
spondence and requests for reprints to Dr. Vicki LeBlanc, University of Toronto Faculty of Medicine, Centre for Research in
Education, 200 Elizabeth Street, 1 Eaton South 565, Toronto, ON M5G 2C4; 416-340-3054 phone; 416-340-3792 fax;
vicki.leblanc@utoronto.ca.
Key words: education, preclinical dentistry, virtual reality simulation
Submitted for publication 2/11/03; accepted 11/24/03
O
ne of the most important skills for any den-
tist is the ability to prepare and restore dam-
aged tissue resulting from carious lesions.
The development of this skill requires mastery of two
components: knowledge of the concepts of the pro-
cedure and the dexterity to perform it. Instruction
regarding the concepts of cavity preparation and dem-
onstrations of techniques can be offered by faculty
in large group sessions. However, the performance
component requires a situation in which students can
repeatedly practice the application of the knowledge
imparted by the instructor. In the past decades, edu-
cators have come to the realization that the clinical
arena may not be an optimal environment for dental
education. There are a number of reasons for this.
Technical skills are increasingly complex due to ad-
vances in knowledge, materials, and technology. In
parallel with the technological advances, financial
restraints have increased the pressure for high pa-
tient turnover at dental school clinics, leaving less
teaching time available to instructors and students.
Finally, concerns over patient safety have led to a
decrease in the acceptance of having students prac-
tice new skills on patients.
1,2
The realization that the clinical setting is not
an ideal environment for skills training, coupled with
recent technological advances, is leading to an in-
creased use of computer applications in health care
education. Growth in computer-aided instruction has
been fueled by increases in computer capacities, soft-
ware applicability and accessibility, and decreased
costs, as well as student demands for the most up-to-
date training possible.
3,4
Computer-aided instruction
can range from computer or web-based tutorials, dis-
cussion groups, and courses to more sophisticated
virtual reality-based, computerized patient simula-
tors and virtual reality-based simulations.
5
Simula-
tors are useful learning tools because they allow for
practice in controlled environments and are adapt-
able to flexible scheduling for students as well as
instructors.
6
They offer an arena for students to test
and observe the results of dental procedures without
any patient morbidity.
7
They also facilitate repeti-
tion of the skill to be learned, offer controlled train-
ing variations, and provide opportunities to quanti-
tatively assess student performance. Students can
thus learn how to deal with the outcomes of their
actions in safe environments.
8
To date, most developments in virtual reality
patient simulation have occurred in the field of sur-
gery, where it is essential for surgeons to master com-
plex procedures prior to performing them on pa-
tients.
6
However, dentistry has recently witnessed the
introduction of simulated environments for the de-
March 2004 ■ Journal of Dental Education 379
velopment of dental skills. Most dental schools have
developed preclinical laboratories where students
practice skills on typodont teeth with articulating
mandibles in life-sized mannequin torsos. While such
a method of practice does provide students with a
means to practice the skills of preparing and restor-
ing teeth, it has limits in the realism provided to the
students and in the quantity and quality of feedback.
The field of dentistry has also seen an increase in the
use of computer-assisted simulation for the training
and assessment of haptic (or tactile-based) skills, such
as the ability to detect carious lesions.
9
Simulators
are also used in preclinical training of dental students,
as a tool to provide a smoother transition to clinic by
broadening students’ preclinical experiences.
5,10
Kaufmann proposes that natural progression of this
technology will be for virtual reality simulators to
be used for education, certification, and recertifica-
tion in all health care fields.
1
Dental operatory and virtual reality patient
simulators (such as the DentSim developed by DenX)
offer the promise of providing practice in a realistic
environment filled with detailed, frequent, and ob-
jective feedback.
11
However, it is unknown if these
characteristics will lead to better or accelerated de-
velopment of skills. The purpose of this study was
to evaluate the effect of training through virtual re-
ality simulation on student performance during pre-
clinical laboratory work, based on standard grading
evaluation procedures at Columbia’s School of Den-
tal and Oral Surgery (SDOS). In this study, we in-
vestigated whether training with a computerized
simulator was comparable to or better than traditional
training in developing the skills necessary for per-
forming operative dentistry procedures.
Methods
Sixty-eight students (forty-four males/twenty-
four females) were enrolled in the second-year course
of preclinical operative dentistry course at
Columbia’s SDOS. The study was introduced to the
students during a large-group session, and all stu-
dents initially volunteered to participate. Based on
space limitations, simulator unit availability, and time
restrictions, twenty of these students were randomly
selected to engage in computerized simulation train-
ing (simulator group: twelve males/eight females)
in addition to the standard 110 hours of traditional
laboratory-based instruction in operative dentistry
alongside the control students. One student (female)
eventually dropped out of the study after the intro-
ductory session, but prior to any individualized train-
ing, due to a lack of interest in completing the com-
puterized simulation training. Her results were not
included in the data analysis. The remaining forty-
eight students (control group: thirty-two males/six-
teen females) continued to receive only the traditional
laboratory-based instruction. In addition to the course
time, all sixty-eight students were free to engage in
extracurricular practice in the traditional preclinical
laboratory on their own time. This research project
received approval from Columbia University’s In-
ternal Review Board, and the students gave signed
consent for their performance to be used as research
data.
Simulator
The DentSim® computer-assisted simulator,
manufactured by DenX Ltd. of Israel,
12
is a clinical
simulator providing real-time tactile feedback with
use of 3D graphics and real time image processing.
The DentSim® unit combines a patient mannequin,
the typodont with a set of teeth, and rotary dental
instruments. In addition, it is equipped with infrared
light emitting diodes and an overhead infrared cam-
era feeding to two computers and a monitor to inter-
pret the spatial orientation of the mannequin and to
produce a three-dimensional image of the patient’s
mouth. The operator can view any cut made in a tooth
from any angle on the monitor.
The software provides detailed feedback com-
paring the operator’s performance with a pre-
programmed acceptable “ideal” cavity preparation
in its database at any point of the procedure. Feed-
back consists of detailed diagrams with quantitative
analysis in various cross sections. Using the feed-
back during the procedure serves as a guidance tool,
while using it strictly at the end simulates an exami-
nation. The entire procedure is saved and stored in
individual student files that can be reviewed later in
movie format with a final evaluation and a list of
error messages, allowing students to actually watch
how each mistake was made. Errors are also audio
signaled in real time while students are working and
can be viewed immediately. This allows students to
know the results of their errors when they are made,
rather than after the preparation has been completed
(as in traditional preclinical instruction). They can
thus develop the skill to make mid-course adjust-
ments that increase both the quality of the final prod-
uct and the efficiency of the skill development it-
self.
13
The virtual environment is enhanced with
380 Journal of Dental Education ■ Volume 68, Number 3
complete patient records including medical and den-
tal history, X-rays, examination notes, diagnosis, and
treatment plan.
The computerized simulation module at Co-
lumbia University’s SDOS has been in use for three
years. To date, students involved in training and par-
ticipating in study have been first- and second-year
students. There is no designated class time for com-
puterized training in the students’ class schedule due
to an already densely filled curriculum. Students
worked during their free time. Time spent in the simu-
lation laboratory was monitored by upperclass stu-
dent teaching assistants and a sign-up sheet.
Procedure
All sixty-eight students received the conven-
tional instruction and training in operative dentistry.
This consisted of in-class faculty lectures and dem-
onstrations, as well as scheduled laboratory practice
in the preparation and restoration of carious lesions.
All students participated in the traditional education
together, with the same faculty instructors. Seven
faculty members provided instruction throughout the
academic year to all sixty-eight students, and the in-
structor-student ratio in the class was, on average,
1:10. All students could also engage in individual
practice outside of regular class hours, and this prac-
tice time was not monitored.
Students who were assigned to the simulator
group received an additional six to ten hours of train-
ing on the computerized simulator in three blocks
over a period of eight months. During Block 1 (De-
cember-April), students received one to two hours
of training with the computerized simulator. This
training consisted of a one-hour introduction and a
hands-on demonstration on interacting with the simu-
lator. During Block 2 (April-May), students in the
simulator group received two to three hours of inde-
pendent practice with the simulator. In Block 3 (May–
July), the students in the simulator group received
an additional three to five hours of training with the
computerized simulator. Each student in this study
group was required to perform two cavity prepara-
tions that were deemed acceptable based on the
DentSim unit’s computerized grading system in each
two-hour session, for a total of four cavity prepara-
tions. Students who fulfilled this requirement in less
than the allotted time were not required to stay for
the remainder of the session. Instructors were not
present to evaluate or aid the students during these
final two training sessions, and an upper-class stu-
dent teaching assistant was present to monitor atten-
dance and provide assistance for any technical diffi-
culties. Students in the simulator group were also
free to engage in individual practice in the traditional
operative dentistry laboratory, as were the control
group students.
Measures
Performance on the practical exams in the pre-
clinical course in Operative Dentistry was used as
an assessment of the effects of the additional six to
ten hours of training with the DentSim. The practi-
cal exams in the course take place in December, April,
May, and July. During these exams that last five to
eight hours each, students perform a variety of cav-
ity preparations and restorations. Two instructors
independently rate the quality of the cavity prepara-
tions and restorations on a scale of 0-100, in inter-
vals of five points, with the lowest grade awarded
being a 60 up to a high of 95. The average of the two
ratings determines the score for a particular prepara-
tion or restoration, and the scores for each item are
averaged to provide the student with an overall score
on the practical component of the exam. Typically,
students complete between three and six procedures
for each exam, with a preparation and restoration of
the same tooth counting as two procedures. All in-
structors grading student performance on the practi-
cal exams, including two investigators in this study,
were blinded as to which students were in the study
or the control groups.
As the year progressed, the procedures included
in the practical exams increased in complexity and
skill required to achieve a passing grade. For ex-
ample, Exam 1 consisted of only class I and II amal-
gam cavity preparations. Exam 4 required compe-
tence in preparing and restoring class II, class IV,
and a gold onlay with retentive boxes and bevels. In
this manner, each exam was considered a cumula-
tive test of skills, with the final examination being
used as a capstone to evaluate competence in the
entire year’s worth of procedures.
Scores for the cavity preparations on each of
the four practical exams in the operative dentistry
course were compared between students in the simu-
lator group and those in the control group. Scores on
the exams were submitted to a 2 x 4 mixed-design
analysis of variance, with group (simulator vs. con-
trol) as a between-subject variable and test (Test 1,
Test 2, Test 3, and Test 4) as a repeated measure.
March 2004 ■ Journal of Dental Education 381
Results
Overall, the average scores on the exams in-
creased throughout the year, F(3, 177)=12.59, MSE
=9.3, p<.01. This result indicates that the students’
ability to prepare cavities improved throughout the
course. Students in the two groups did not differ on
their overall performance scores during the year, F(1,
59)=.352, MSE=23.12, p=.56. However, we observed
a significant group by test interaction, F(3, 177)=
4.15, p<.05. On the early exams, the students in the
control group obtained higher scores than did the stu-
dents in the simulator group. However, by the final
exam, the students in the simulator group showed a
trend towards obtaining higher scores than did the
students in the control group (78.4 vs. 76.6, p=.07).
An independent t-test indicated that the exam scores
of the students in the simulator group improved sig-
nificantly more from the first to the fourth exam than
did the exam scores of the students in the control
group (improvement of 4.8 pts vs. 1.4 pts, p=.01). In
a few short hours of training, the DentSim group
improved significantly more than the control stu-
dents. See Table 1 for the scores on each of the ex-
ams.
Discussion
The results of this study suggest that virtual
reality simulation provides an effective training
method for the development of operative dentistry
skills in students. Students assigned to the simulator
group demonstrated better improvements in exam
scores throughout the year than did students in the
control group. These findings are very positive, given
that the individual practice time never exceeded eight
hours throughout the academic year.
Our results are in line with other research on
the effect of computer simulation in the training of
dentistry skills. Buchanan has published some of the
few studies investigating the effectiveness of com-
puter simulation instruction. Her findings show that
students learn procedures faster with computerized
simulation training than students who train in tradi-
tional laboratories.
5
She hypothesized that the rea-
son for this acceleration of learning is that the stu-
dents are able to complete more preparations per hour
(up to twice as many) than students in the traditional
laboratory.
We believe that the advantage of computerized
simulation training comes from a variety of factors.
In traditional operative dentistry instruction, preclini-
cal students practice on mannequins in large groups.
There are limits in the objectivity and the frequency
of the feedback provided by the instructors in tradi-
tional training. The laboratories are typically large
ones, and the ratio of instructor to student is low.
Thus, students often have to wait extended periods
of time before receiving any feedback. Research has
shown that, for the most effective instruction, some
external feedback should be offered when students
are practicing.
14
While this study does provide evidence in sup-
port of technology in the training of dental students,
further research needs to be conducted to determine
the optimal coordination of the traditional didactic
instruction with emerging technology-based instruc-
tion. First, it is unknown what is the optimal amount
of training required on the computerized simulator
to lead to improvements in the acquisition of skills.
Anecdotal evidence from the University of Pennsyl-
vania showed that postgraduate dentists required, on
average, five hours of training on a computerized
simulator before realizing significant benefit based
on the computerized grading system. In this study,
students just barely crossed the five-hour plateau.
This finding suggests that more extensive training
time would lead to more profound improvements in
skill. Second, it is unknown when is the best time to
schedule computerized simulation training during the
acquisition phase of operative skills. It may be hy-
pothesized that the earlier the training, the better,
while others have argued that a tactile skill cannot
be fully optimized without the didactic knowledge
base in place.
15,16
We are currently investigating the
benefits of computerized simulation training incor-
porated early versus later in the skills acquisition.
Table 1. Performance on practical exams
Exam Exam 1 Exam 2 Exam 3 Exam 4
Simulator Group 73.6 73.9 76.9 78.4
n=19 (.84)* (.83) (.80) (.81)
Control Group 75.3 75.8 76.7 76.6
n=48 (.57) (.56) (.54) (.54)
Average 74.4 74.9 76.8 77.5
(.51) (.50) (.48) (.49)
*Numbers in parentheses are standard errors of the mean.
382 Journal of Dental Education ■ Volume 68, Number 3
We are aware of limitations in the design of
the study, most notably that we were not able to con-
trol the amount of time students practiced the skill
on their own time. Thus, we are not in a position to
determine whether the increased performance of the
simulator group results from training specifically
with the virtual reality simulator or whether it sim-
ply results from them having more practice time over-
all than the students in the control group. Our belief
is that the six to ten hours of actual individualized
training was insignificant compared to the 110 hours
of in-class laboratory time as well as any additional
hours of self-practice. An informal survey of the stu-
dents revealed that they spent, on average, approxi-
mately eighty-three hours practicing outside of class
throughout the year. We believe those six to ten hours
had a greater impact due to the individualized atten-
tion and evaluation each student in the DentSim
group received, rather than due to significantly extra
time spent on practice. We are currently designing
studies investigating this question.
While this study indicates that students who
trained on the computerized simulator showed im-
provements on exams of operative dentistry, we wish
to stress that the training on the simulators was not a
stand-alone activity. Rather, training with the simu-
lator was placed within the context of initial class-
based instruction so that the trainees would learn the
relevant principles of the skills of operative dentistry.
Research in skill acquisition has shown that knowl-
edge of performance (error information related to the
characteristics of the performance) and knowledge
of results (comparison between actual outcome and
desired outcome) are required for acquisition and
improvement of motor skills.
15,16
Such knowledge can
be acquired during class-based instruction where the
students learn demonstration through lectures and,
by asking questions, how to discriminate between
the desired performances and outcomes and ones that
contain errors. Thus, it is our belief that the coordi-
nation of training on simulators with class-based in-
struction is necessary to ensure that the skills per-
fected on the simulator are the correct ones.
Conclusion
This study is one of the first investigating the
effects of computerized simulation on the develop-
ment of operative dentistry skills. The results indi-
cate that students in the DentSim simulator group
improved their scores significantly more from the
first to the fourth examination of the year than did
students in a control group who did not receive aug-
mented instruction by the simulator. The simulation
group improved from a mean score of 73.6 percent
on the first exam of the year to 78.4 percent on the
fourth exam, which served as a cumulative capstone
assessment of the students’ operative skills. The con-
trol group (traditional training only) improved from
75.3 percent on the first exam to 76.6 percent on the
fourth exam. However, while the use of simulators
for the training of dental holds promise, their inte-
gration into the curriculum should not go unchecked.
Rather, the implementation of simulators should be
guided by theory and by relevant research regarding
how individuals obtain and process information. For
this last purpose, simulators can serve the additional
function of aiding researchers in determining areas
of clinical practice that need enhancement and of
guiding faculty in modifying curricula.
REFERENCES
1. Kaufmann CR. Computers in surgical education and the
operating room. Ann Chir Gynaecol 2001;90:141-5.
2. Wanzel KR, Ward M, Reznick RK. Teaching the surgical
craft: from selection to certification. Curr Probl Surg
2002;39(6):573-660.
3. Keane DR, Norman GR, Vickers J. The inadequacy of
recent research on computer-assisted instruction. Acad
Med 1991;66(8):444-8.
4. Larbuisson R, Pendeville P, Nyssen AS, Janssens M,
Mayne A. Use of anaesthesia simulator: initial impres-
sions of its use in two Belgian university centers. Acta
Anaesthesiol Belg 1999;50:87-93.
5. Buchanan JA. Use of dental simulation technology in den-
tal education. J Dent Educ 2001;65(11):1225-31.
6. Derossis AM, Fried GM, Abrahamowicz M, Sigman HH,
Barkun JS, Meakins JL. Development of a model for train-
ing and evaluation of laparoscopic skills. Am J Surg
1998;175:482-7.
7. Kokoska MS, Citardi MJ. Computer-aided surgical re-
duction of facial fractures. Facial Plast Surg Clin North
Am 2000;16(2):169-79.
8. Miller MD. Education, training, and proficiency of pro-
cedural skills. Prim Care 1997;24(2):231-40.
9. Thomas G, Johnson L, Dow S, Stanford C. The design
and testing of a force feedback dental simulator. Comput
Methods Programs Biomed 2001;64:53-64.
10. Suvinen TI, Messer LB, Franco E. Clinical simulation in
teaching preclinical dentistry. Eur J Dent Educ
1998;2(1):25-32.
11. Carr MM, Reznick RK, Brown DH. Comparison of com-
puter-assisted instruction and seminar instruction to ac-
quire psychomotor ad cognitive knowledge of epistaxi
management. Otolaryngol Head Neck Surg 1999;121(4):
430-4.
12. DenX Ltd., DenX Advanced Dental Systems. At:
denx.com. Accessed: January 18, 2003.
March 2004 ■ Journal of Dental Education 383
13. Newell KM, Morris LR, Scully DM. Augmented infor-
mation and the acquisition of skill in physical activity.
Exerc Sports Sci Rev 1985;13:235-61.
14. Rogers DA, Regehr G, Yeh KA, Howdieshell TR. Com-
puter-assisted learning versus a lecture and feedback semi-
nar for teaching a basic surgical technical skill. Am J Surg
1998;175:508-10.
15. Feil P. An assessment of the application of psychomotor
learning theory constructs in preclinical laboratory instruc-
tion. J Dent Educ 1992;56(3):176-82.
16. Kovacs G. Procedural skills in medicine: linking theory
to practice. J Emerg Med 1997;15(3):387-91.
