Hepatitis C infection and associated oral health problems.
ABSTRACT Hepatitis C infection is widespread throughout the community. This study aimed to assess the status of oral health of persons infected with hepatitis C. DMFT and CPITN indices were recorded at a clinic providing priority dental care for people with hepatitis C infection. The data were compared with information from an existing survey of general dental patients. Social impact was assessed using a modified Oral Health Impact Profile questionnaire. The DMFT index differed significantly between hepatitis C and general patients. The number of decayed and missing teeth was greater in those infected with hepatitis C for all patients aged between 25 and 50 years. Although there was no significant difference in CPITN categories for subjects evaluated, a marked trend for poor periodontal health was noted for those individuals with hepatitis C. Salivary flow was reduced in 50 per cent of hepatitis C infected subjects. Social impact was significantly affected with 71 per cent of hepatitis C subjects reporting painful aching in the mouth and 56 per cent having difficulty in relaxing. In conclusion, the results from the project strongly indicate an urgent need for priority delivery of dental care for people with hepatitis C infection.
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ABSTRACT: Over 170 million patients worldwide are chronically infected with Hepatitis C virus (HCV); making it a globally important infection. Dentists constantly handle sharp instruments infected with biological fluids and are therefore considered at high-risk of contracting HCV infection. Needle-stick injuries seem to be the most common route of exposure to blood-borne pathogens in dental practice. Moreover, endodontist's constant use of sharp instruments such as endodontic files with limited operative vision in a small working field (i.e. root canal system) increases their risk of exposure to infection. The aim of this study was to review the epidemiology of HCV infection in dental healthcare staff and the tests required for its diagnosis. We also look at the protocols for dental treatment in infected individuals and screening and dental examination tailored for HCV patients.Iranian endodontic journal. 01/2014; 9(3):169-73.
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ABSTRACT: Extrahepatic manifestations (EHMs) of hepatitis C virus (HCV) infection can affect a variety of organ systems with significant morbidity and mortality. Some of the most frequently reported EHM of HCV infection, involve the oral region predominantly or exclusively. Oral lichen planus (OLP) is a chronic inflammatory condition that is potentially malignant and represents cell-mediated reaction to a variety of extrinsic antigens, altered self-antigens, or super antigens. Robust epidemiological evidence support the link between OLP and HCV. As the virus may replicate in the oral mucosa and attract HCV-specific T lymphocytes, HCV may be implicated in OLP pathogenesis. Sjögren syndrome (SjS) is an autoimmune exocrinopathy, characterized by dryness of the mouth and eyes and a multitude of other systemic signs and symptoms. SjS patients have also an increased risk of non-Hodgkin lymphoma. Patients with chronic hepatitis C do frequently have histological signs of Sjögren-like sialadenitis with mild or even absent clinical symptoms. However, it is still unclear if HCV may cause a disease mimicking SjS or it is directly responsible for the development of SjS in a specific subset of patients. Oral squamous cell carcinoma is the most common oral malignant tumour and at least in some part of the world could be linked to HCV.World Journal of Gastroenterology 06/2014; · 2.55 Impact Factor
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ABSTRACT: Hepatitis C virus (HCV) infection in more than 170 million chronically infected patients with no developed preventive vaccine is a globally important issue. In addition to expected hepatic manifestations, a number of extrahepatic manifestations, such as mixed cryoglobulinemia, glomerulonephritis, polyarteritis nodosa, rashes, renal disease, neuropathy, and lymphoma, have been reported following HCV infection, which are believed to be influenced by the virus or the host immune response. HCV combination therapy with pegylated interferon and ribavirin might be associated with side effects as well. The association of HCV with special oral conditions has also been reported recurrently; the mechanism of most of which remains unclear. This article reviews the association of HCV infection with some of the oral conditions such as oral health, Sjogren's syndrome, lichen planus and oral cancer.Saudi Journal of Gastroenterology 19(6):245-51. · 1.22 Impact Factor
C infection are prone to tooth decay, suffer loss of
esteem due to poor oral aesthetics and also have
difficulty with diet due to poor oral health. If indeed
there is a significant oral health problem within this
group of the population, then there will need to be
serious consideration given to the management of
their dental needs as the population affected is
s u b s t a n t i a l . Because many people infected with
hepatitis C are eligible for dental care provided by
government clinics, the possibility that this group
might require greater provision of oral health care
also poses a public health concern.
The reported poor oral health of people with
hepatitis C has been attributed to factors such as
injecting drug use, methadone medication and poor
utilization of dental services.Methadone medication
is often prescribed to assist people overcome heroin
addiction. The sugar content and side effects of
methadone such as xerostomia are well known and
these characteristics have been ascribed as causes of
rampant caries and poor oral health in these
patients. To assume that lifestyle issues such as
heroin use,7methadone medication, poor dental
attendance, inadequate diet and poor oral hygiene
result in poor oral health is a simplistic view. None
of these factors has been accurately assessed in the
literature or consequently addressed, except that the
p r e p a r ation of methadone has been altered to
eliminate the sugar content in the assumption that
this did indeed contribute to poor dental health.
Many people infected with hepatitis C have a very
limited injecting drug use history and have never
taken methadone to overcome drug dependency.
Others infected with hepatitis C have never injected
drugs at all but either acquired their infection from
medical sources or the route of transmission is
unknown. It needs to be ascertained if this group of
people infected with hepatitis C also demonstrates
significant dental disease.For example,if xerostomia
is considered to be a major contributing factor in
dental and oral disease, then there may be
undetermined factors resulting from the chronic
These are estimated to be 196 000 people infected
with hepatitis C in Australia. Previous studies1-5have
projected the medical treatment requirements for
these people based on epidemiological statistics,
however, there is little information available on the
oral health needs of people infected with hepatitis C
virus.6Anecdotal evidence strongly indicates that, as
a cohort within the population,people with hepatitis
108Australian Dental Journal 2000;45:2.
Hepatitis C infection and associated oral health
E .A . C o ates,* D. Brennan,† R. M . Logan,* A . N. Goss,‡ B. Scopacasa,* A . J. Spencer,† E. G o r k i c *
*South Australian Dental Service.
†Australian Institute of Health and Welfare Dental Statistics and
‡Faculty of Dentistry,The University of Adelaide.
SCIENTIFIC A R T I C L E
Australian Dental Journal 2000;45:(2):108-114
Hepatitis C infection is widespread throughout the
community. This study aimed to assess the status
of oral health of persons infected with hepatitis C.
DMFT and CPITN indices were recorded at a clinic
providing priority dental care for people with
hepatitis C infection. The data were compared with
information from an existing survey of general
dental patients. Social impact was assessed using
a modified Oral Health Impact Profile questionnaire.
The DMFT index differed significantly between
hepatitis C and general patients. The number of
decayed and missing teeth was greater in those
infected with hepatitis C for all patients aged
between 25 and 50 years. Although there was no
significant difference in CPITN categories for
subjects evaluated, a marked trend for poor
periodontal health was noted for those individuals
with hepatitis C. Salivary flow was reduced in 50
per cent of hepatitis C infected subjects. Social
impact was significantly affected with 71 per cent of
hepatitis C subjects reporting painful aching in the
mouth and 56 per cent having difficulty in relaxing.
In conclusion, the results from the project strongly
indicate an urgent need for priority delivery of
dental care for people with hepatitis C infection.
Key words:Hepatitis C, DMFT, CPITN, social impact,
(Received for publication December 1998. Revised
February 1999. Accepted February 1999.)
hepatitis C viral infection itself, which contribute to
the reported levels of oral disease.Although as yet no
human research has been carried out to support this
concept, the transgenic mouse model8proved that
xerostomia was the first clinical symptom observed
in mice infected with hepatitis C.
The provision of dental care falls outside main-
stream medical funding and the costs of seeking
dental treatment are often prohibitive to people with
hepatitis C infection. In addition, people infected
with hepatitis C who are eligible for Stat e
government dental treatment are often placed on
extremely long waiting lists. It is possible that the
inaccessibility of dental treatment also contributes to
the reported extensive tooth destruction and
subsequent poor oral health.
In order for the oral health of people with hepatitis
C infection to be improve d , it needs to be
d e t e rmined if they are disadvantaged as a community
group and, if so, what contributing factors can be
The aims of this study were:
1. To ascertain the oral health status of people
infected with hepatitis C in South Australia.
2. To determine if their oral health status was
worse than that of other community groups of
similar age, gender and economic circumstance.
3. To determine the impact of oral health on the
quality of life in subjects with hepatitis C infection.
Support for the development of a clinic to assess
and manage the dental needs of people infected with
hepatitis C was provided by the HIV and Related
P r o grams Unit of the Department of Human Serv i c e s ,
South A u s t r a l i a . Initial collection of data wa s
obtained from individuals infected with hepatitis C
who were eligible for South Australian Government
dental care and were referred for assessment and
care to the clinic at the Adelaide Dental Hospital.
I n f o rm ation was obtained from these subjects
between April 1998 and October 1998.Two dentists
at the Adelaide Dental Hospital who had undergone
s t a n d a r d i z ation of examination techniques examined
the subjects. Caries experience was recorded for all
teeth.9Carious lesions were diagnosed by clinical
examination, panoramic radiograph and bitewing
radiographs. The clinical appearance of all oral
tissues was recorded. The presence of calculus,
gingival bleeding and periodontal pocket depth were
noted for index teeth from all sextants. Community
Pe riodontal Index Tr e atment Needs (CPITN)
categories10were deduced from this data.
Other information noted included medications
being taken,a history of abnormal liver function and
any other relevant medical history that might be
pertinent to delivery of dental treatment. Dentists
need to be aware of the risks of hepatocellular
dysfunction including poor clotting and the poten-
tial toxicity of some prescription medicat i o n s.1 1
Subjective data were sought from subjects with
hepatitis C infection on the impact of their oral
health status on their quality of life and on the
dryness of their mouths.12
Of the 87 subjects with hepatitis C infection, 82
were assessed for changes in saliva flow and pH.The
subjects’ salivary pH was recorded using Duotest
pH 5.0-8.0 indicating paper (Macherey – Nagel
GmbH, D¨ uren, Germany). Salivary flow tests were
p e r f o rmed to determine the presence of xe r o s t o m i a .1 3
S a l i va ry flow was measured for resting and stimulat e d
phases. A fixed collection time of five minutes was
set for both unstimulated and stimulated saliva
samples. All samples collected were of whole saliva.
Parafilm M14(American National Can, Greenwich,
CT, USA) was the stimulant used to obtain all
stimulated saliva samples. Photographic records of
the mouth were taken using a Pentax SFXn camera
(Pentax, Englewood, CO, USA) with a ring flash
and Kodachrome 64 ASA 35 mm transparency film
(Eastman Kodak Company, Rochester, NY, USA).
As well as the data collected from the clinic at the
Adelaide Dental Hospital, data were taken from an
existing survey of general dental patients who had
attended public dental clinics in South Australia
during the 1995-96 period. Health concession cards
were a requisite for eligibility to attend these clinics.
A total of 753 general patients who we r e
u n e m p l oyed or from low income groups wa s
a s s e s s e d .1 5S t a n d a r d i z ation of examination techniques
was not performed for dentists who recorded data
for general patients. Age stratified data on DMFT
and CPITN were compared between general
patients and hepatitis subjects.
Also, data were collected from a telephone inter-
view survey on the social impact of oral health, 581
persons were randomly selected and interviewed.15
The interview contained two of the oral health
impact questions given to the subjects with hepatitis
C infection.Findings from the second and third data
sources were reported previously.15,16
Inferential statistical analysis was carried out for
c a ries experi e n c e , p e riodontal health and the
reported social impact. Means were tested using
analysis of variance and proportions were tested
using chi squared tests.17
All subjects were entered into the study with the
a p p r oval of The Unive rsity of Adelaide Ethics
Committee for Human Experimentation. Subjects
were advised of the reasons for the project and fully
informed consent for participation in the project was
obtained before proceeding.
Australian Dental Journal 2000;45:2.109
110Australian Dental Journal 2000;45:2.
A total of 87 hepatitis C infected individuals who
were eligible for South Australian Gove rn m e n t
dental care were assessed in the current study.Table
1 shows the age, gender and demographic details of
subjects. All subjects were dentate.
Figure 1 shows that the number of decayed and
missing teeth and the DMFT in subjects with
hepatitis C infection was greater for all patients aged
between 25 and 54 years. In the age range of 35-44
years, subjects with hepatitis C had a threefold
increase in the number of decayed teeth compared
with patients from the same age group attending
public dental health clinics (analysis of variance;
p<0.001). The number of missing teeth was also
significantly greater for these subjects (p<0.01).The
number of filled teeth was less in subjects with
hepatitis C in the 25-34 year age group but in the
35-44 age group, which constituted 64 per cent of
the hepatitis subjects, the number of filled teeth was
the same (p<0.01).
CPITN scores, presented in Fig. 2, demonstrated
a trend for poor periodontal health in subjects with
h e p atitis C. Subjects were more likely to have
gingival bleeding in the age groups 25-34 and 35-44
years and deep pockets in each age group.This was
not statistically significant for the number of subjects
Table 1. Characteristics of dental patients
% of patients
Sex of patient
Age group of patient
Language spoken at home
Country of birth
Fig. 1. – Caries experience of hepatitis C patients and general patients at South Australian
public dental services.
Fig. 2. – CPITN categories of hepatitis C patients and general patients at South Australian
public dental services.
Mean no. of teeth
Hep C General Hep CGeneral Hep C General
25-34 years35-44 years45-54 years
Hep C GeneralHep C GeneralHep C General
25-34 years35-44 years45-54 years
Pocket 6+ mm
Pocket 4-5 mm
Xerostomia was noted objectively in 50 per cent of
the 82 subjects tested (38 males and 44 females),
with 37 per cent (14/38) of the male and 59 per cent
(26/44) of the female subjects demonstrating clinical
xerostomia. Sixteen subjects (nine females and seven
males) subjectively considered they had dry mouths
but clinically registered normal saliva ry flow.
Conversely, there were ten subjects who did not
complain of dryness but demonstrated very poor
salivary flow (five females and five males).
Medication was taken by 39 of the subjects.
Methadone medication was taken by 18 subjects
(ten males and eight females) and clinical evidence
of xerostomia was noted in 33 per cent. Ten of these
subjects complained of a dry mouth but clinical
findings indicated normal salivary flow in four of
these ten subjects.A further five subjects were taking
antidepressant medication and three of these
registered very low salivary flow.
The impact of oral health was assessed by two
questions, which are presented in Table 2. Overall,
significantly higher percentages of subjects with
hepatitis C infection reported painful aching in the
mouth and difficulty relaxing because of dental
problems.This pattern occurred in most age groups
despite some small cell sizes, particularly for those
aged 45-54 years.
The presence of lichen planus was noted in seven
of the 87 subjects.
The results indicate that there is a marked
d i s c r e p a n cy between the oral health of those infected
with hepatitis C and the comparison group of the
population. As both groups were eligible for public
dental care it is presumed that both had similar
access problems and difficulties with waiting lists.
However, the caries experience of those subjects
infected with hepatitis C was significantly worse
than that of the general patients examined in the
public clinics. The number of missing teeth in
p atients with hepatitis C infection was also
significantly higher than in the general patients and
periodontal health tended to be poor. All of this is
d e m o n s t r ated in Fig. 3 . One of the proposed
contributing factors to poor oral health of subjects
infected with hepatitis C was the lack of access to
dental treatment.The results tend to discount this as
a significant factor as both groups had received
similar numbers of restorations, proving that people
with hepatitis C were attending the dentist but that
treatment was obviously proving unsuccessful or was
fa i l i n g .The older age groups in fact were more likely
to have a greater number of fillings, again high-
lighting a difference in dental need between those
with hepatitis C infection and the general eligible
Another factor implicated in poor oral health
associated with hepatitis C infection was the use of
methadone medicat i o n . In the Adelaide Dental
Australian Dental Journal 2000;45:2. 111
Table 2. Reported social impact of oral health
% of persons reporting impact
Adelaide sample*Hepatitis C patients p (?2)
Had painful aching in mouth
*Dentate, card-holders,aged 25-54 years.
Fig. 3. – Decayed and missing teeth in a patient with hepatitis C
112Australian Dental Journal 2000;45:2.
Hospital clinic, it was observed that people on
methadone medication who presented with decayed
teeth predominantly had root caries with many sub-
gingival lesions.Oral hygiene appeared to improve in
those not currently injecting drugs but the ongoing
tooth destruction continued. Only 20 per cent of
subjects with hepatitis C infection attending the
clinic were taking methadone and of these only 33
per cent demonstrated clinical xe r o s t o m i a .
Certainly, where carious lesions were present in this
s u b gr o u p, they did indeed resemble the classic
picture of cervical lesions noted in the clinic and
these lesions often extended subgingivally (Fig. 5).
As 66 per cent of subjects on methadone did not
present with clinical xerostomia and not all subjects
taking methadone presented with decayed teeth, the
use of this medication cannot be directly blamed for
the presence of oral disease.
H e p atitis C infection and treatment for that
infection have resulted in the onset of clinical
d e p r e s s i o n .3C o n s e q u e n t l y, some subjects with
hepatitis C (6 per cent) were taking antidepressant
medication. Marked xerostomia was noted in this
group and this medication would certainly appear to
be a contributing factor in dental disease.
Very few of the subjects presenting to the clinic
admitted ongoing injecting drug use. It is quite
possible that tooth destruction does occur during
the period of heroin use. However, for many of the
subjects attending the clinic, injecting drug use had
occurred over a very small period of time and often
many years earlier, whereas their oral problems of
concern were ongoing and had occurred subsequent
to that period.
It was not anticipated that subjects with hepatitis
C would have periodontal problems of gr e at e r
p r o p o rtions than general pat i e n t s. The trend
demonstrated by the results for patients infected
with hepatitis C to have poor periodontal health is
disturbing. Although the data is not statistically
significant, it is possible that this trend will become
more apparent as a larger number of subjects are
evaluated. It is possible that diet and other social
influences contribute to this trend and it further
complicates the development of dental treatment
plans that have successful outcomes.
Lichen planus was noted in only seven of the 87
subjects with hepatitis C infection. Many of the
subjects with hepatitis C infection could not
accurately assess the period of time they had been
infected. Certainly in the older age group, hepatitis
C infection was likely to have been of longer
duration. It is possible that for those more recently
infected, mucosal problems such as lichen planus
will develop later in the course of their hepatitis C
infection and, as some investigators18have correlated
an increased risk of malignancy with this lesion,
ongoing monitoring is import a n t .
i nve s t i g ations have been undertaken to assess
correlation between hepatitis C-related liver disease
and the presence of lichen planus,19it appears that
other oral health issues pertaining to hepatitis C
infection may be more immediate.
Sporadic intermittent dental care will not address
the oral health needs of those people with hepatitis
C infection. If oral health and prognosis for dental
treatment is to be improved,then oral care treatment
plans incorp o r ating
components need to be developed so that the
combined influences of medication, injecting drug
use and the effect of infection with a chronic virus
will be overcome. The use of topical fluorides, oral
hygiene instruction, dietary counselling and regular
recall should be combined into a comprehensive
treatment protocol for patients with hepatitis C
infection. Remineralization, rather than restoration
of cervical lesions, may provide a more successful
long-term outcome. Regular recall in public dental
clinics is not a service generally provided except
where dental treatment can adversely affect some
medical conditions. The results of this project
suggest that as subjects have a large number of
missing teeth in addition to numerous restored
teeth, there is a high rate of dental treatment failure.
Regular recall would hopefully address this issue and
provision of dental care would prove successful and
consequently cost efficient.
Management of periodontal needs is a more
complex issue. The success of the comprehensive
t r e atment protocol outlined above needs to be
established, as this may impact on the periodontal
disease pattern, eliminating the need for invasive
The impact of hepatitis C on the oral health of
subjects with hepatitis C infection was assessed by
only two questions, as the results from ongoing
surveys on general patients are yet to be evaluated.
Notably there was an impact, even in this restricted
survey, which is supported by prior findings of the
impact of chronic disease on oral health.20The
number of people with hepatitis C infection report-
ing oral pain suggests an impact on the quality of life
and this is supported by other studies2 1where lethargy
and pain have been significant problems associated
with hepatitis C infection.
The results from this study suggest that routine
delivery of dental care for people with hepatitis C
infection who are eligible for treatment in public
dental clinics will be unacceptable due to the lengthy
waiting lists. Figures 4 and 5,panoramic radiographs
taken five years apart of the same patient, reveal the
dental destruction that can occur as a result of being
placed on a waiting list for dental treatment. Those
subjects not eligible for public treatment will also
A l t h o u g h
long-term preve n t i o n
find the cost burden of dental treatment ove r w h e l m i n g
because of the extent of their dental problems.The
benefit of having good oral health will provide an
improved response to medical and social care and a
greater chance of employment. The cost benefit to
the community of providing priority dental care for
people with hepatitis C infection would consequently
Photographic records have been taken of subjects
to monitor the success of programmes that have
been implemented. O b v i o u s l y, the longi t u d i n a l
study of oral treatment needs and evaluation of
implemented programmes will depend on recognition
of the need for priority dental care for people with
hepatitis C infection.To achieve this outcome it will
be necessary for a demand for oral care from the
affected community and for oral health to be
i n c o rp o r ated into gove rnment
management of hepatitis C infection.
The preliminary results from this pilot project to
assess the oral health requirements of people infected
with hepatitis C strongly indicate an urgent need for
priority delivery of dental care for this group. Dental
treatment needs to incorporate a strong preventive
programme and oral health education component in
order to sustain health improvement. There is a
significant alteration in salivary flow, a factor likely
to result in oral disease.
Oral disease of extensive proportions has been
found in people with hepatitis C infection.
Considering the estimated large numbers of people
infected with hepatitis C, this could pose a public
health concern and these issues need to be raised
with various government agencies and hepatitis C
Further, issues of infection control, prevention of
disease transmission, and the broader health
i m p l i c ations of providing dental treatment for
people with serious liver dysfunction,will need to be
well understood by the dental profession.
This research was supported by the HIV and
Related Programs Units, Department of Human
Services, South Australian. Secondary analysis was
u n d e rtaken of data ori ginally collected by the
Australian Institute of Health and Welfare’s Dental
Statistics and Research Unit.
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Australian Dental Journal 2000;45:2.113
Fig. 4. – Panoramic radiograph taken in 1993 of a 26 year old patient with hepatitis C infection.
Fig. 5. – Panoramic radiograph taken of the patient in Fig. 4 in 1998, demonstrating extreme dental destruction as a result of being placed on
waiting lists for treatment.
114Australian Dental Journal 2000;45:2.
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Address for correspondence/reprints:
Dr E. A. Coates,
Medically Compromised Unit,
Adelaide Dental Hospital,
Adelaide, South Australia 5000.