Journal of the Formosan Medical Association (2016) 115, 867e875

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ORIGINAL ARTICLE

Dental service use among patients withspecific disabilities: A nationwidepopulation-based study

Po-Yen Lin a,b, Kuang-Wen Wang c, Yu-Kang Tu d,e,Hsin-Ming Chen d,f, Lin-Yang Chi a,*, Chun-Pin Lin d,f,*

a Department of Dentistry, School of Dentistry, National Yang-Ming University, Taipei, Taiwanb Department of Dentistry, Shin Kong Wu Ho-Su Memorial Hospital, Taipei, Taiwanc Aþ Inc. Headquarters, Taipei, Taiwand Department of Dentistry, National Taiwan University Hospital, Taipei, Taiwane Institute of Epidemiology and Preventive Medicine, College of Public Health, National TaiwanUniversity, Taipei, Taiwanf Department of Dentistry, School of Dentistry, National Taiwan University, Taipei, Taiwan

Received 8 August 2015; received in revised form 12 September 2015; accepted 14 September 2015

KEYWORDSdental service;disability;quality assessment;Taiwan NationalHealth InsuranceDatabase

Conflicts of interest: The authors h* Corresponding authors. Departme

Hospital, Number 1, Changde StreetDentistry, National Yang-Ming Univers

E-mail addresses: chily@ym.edu.tw

http://dx.doi.org/10.1016/j.jfma.2010929-6646/Copyright ª 2015, FormosCC BY-NC-ND license (http://creative

Background/purpose: The Taiwan National Health Insurance program has allocated a specificfund for dental services to patients with specific disabilities (PSDs); however, the trends andthe quality are unknown. In this study, we conducted quantity analyses and quality assess-ments of dental service use among PSDs using a nationwide population-based database.Methods: PSDs were identified according to the codes of diagnosis fee. Quantity analysesincluded the number of patients receiving dental services, the number of visits, and the per-centages of categories of dental service use. Quality assessments included refilling rates foroperative dental treatments and unfinished rates for endodontic therapies.Results: For quantity analyses, dental services were accessible to 3e4% of patients with dis-abilities and were mostly provided to younger PSDs. The general population received moreoperative and endodontic therapies, and PSDs received more periodontal therapies. Forquality assessments, the teeth of PSDs had a 9.74e15.07% refilling rate, which was higherthan that of the general population (1.39e6.37%). Furthermore, the teeth of PSDs had a32.03% unfinished endodontic rate, which was higher than that of the general population(21.42%).Conclusion: During 2010e2012, only 3e4% of patients with disabilities had access to dentalservices, mostly provided to younger PSDs. Teeth of PSDs had higher refilling rates and

ave no conflicts of interest relevant to this article.nt of Dentistry, School of Dentistry, National Taiwan University and National Taiwan University, Zhongzheng District, Taipei City 10048, Taiwan (C.-P. Lin); Department of Dentistry, School ofity, Number 155, Section 2, Linong Street, Beitou District, Taipei City 11221, Taiwan (L.-Y. Chi).(L.-Y. Chi), pinlin@ntu.edu.tw (C.-P. Lin).

5.09.007an Medical Association. Published by Elsevier Taiwan LLC. This is an open access article under thecommons.org/licenses/by-nc-nd/4.0/).

868 P.-Y. Lin et al.

Specific dSevere/extremModerate (00Mild (00303CMental disord

Figure 1 Operative definitions ofstudy on the basis of data obtained

unfinished endodontic sessions than the general population. We suggest that a more compre-hensive dental care system is necessary to improve the quantity and quality of dental ser-vices, especially in middle-aged and older PSDs.Copyright ª 2015, Formosan Medical Association. Published by Elsevier Taiwan LLC. This is anopen access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).

Introduction

Taiwan implemented the Physically and Mentally DisabledCitizens Protection Act in 1997. Improvement of the wel-fare of people with physical or mental disabilities has led torapid increases in the number of registered citizens withphysical or mental disabilities. By the end of 2012, thenumber of citizens with disabilities in Taiwan exceeded 1.1million, demonstrating an increase of 350,000 in the lastdecade; these citizens account for 4.79% of the totalTaiwanese population.1

People with disabilities are more likely to be restrictedby difficulties in communication and mobility, and there-fore, they are more susceptible to poorer oral health thanthe general population.2 In 2005, Huang and his colleagues3

examined the oral health status of adults with disabilities,and the results showed that the caries prevalence in per-manent dentition among people with disabilities was91.96%, which was substantially higher than that of 86.61%among the general population; 32.37% of teeth were filled,which was substantially lower than the rate of 40.22%among the general population. Recent studies have alsoreported a mean decayed, missing, and filled permanentteeth (DMFT) index of 13.8 among children with disabilitiesreceiving dental treatments under general anesthesia and amean DMFT index of 17.68 among adult inpatients withschizophrenia, indicating that a comprehensive dental caresystem is needed to improve dental service utilization bypatients with disabilities.4,5

Therefore, the government launched the “Dental Ser-vices Network for Disabled Patients” in 2006 to establish asystem for the provision of dental services by hospitals anddental clinics to more patients with disabilities. As of 2013,more than 700 dental clinics provide dental services topatients with disabilities. Moreover, the Taiwan NationalHealth Insurance program has allocated a specific fund forthe provision of dental services to patients with disabilitiessince 2002. The target population of the program initially

Participants who ever receiclaiming from Taiwan’s Natiduring 2010–2012

isabilitiese (00128C)

301C))ers (00302C)

Other disaAll disabilitiesspecific disab

patients with specific disabilitfrom the Taiwan National Hea

included patients with cleft lip and palate but expanded in2010 to include patients with other types of disability,including limb disorders, autism, chromosomal defects,mental retardation, multiple disabilities, intractable epi-lepsy, chronic psychosis, chronic unconsciousness, and se-nile dementia [patients with specific disabilities (PSDs)].The budget of the program has also increased, with morethan US$13 million dollars (with the exchange rate beingUS$1 Z NT$29.3 in December 2012) being allocated eachyear since 2011. Although this program should benefit morepatients with disabilities, it is also crucial to monitor thequality of dental treatment. The purpose of this study wasto conduct quantity analyses and quality assessments ofdental services utilized by PSDs using a nationwidepopulation-based database.

Methods

Study database

The Taiwan National Health Insurance program, establishedin 1995, is a compulsory health insurance program thatprovides health care coverage to almost 99% of the 23.5million residents of Taiwan. Our study database includedthe records of the registration and dental claims from allbeneficiaries from 2010 to 2012. This study was approved bythe Institutional Review Board of National Taiwan Univer-sity Hospital (Approval Number 201306077RINC).

Study population

The current retrospective cohort study included all patientswho receiveddental services from2010 to 2012. Patientswithabnormal registry data, such as missing sex and inconsistentbirth data, were excluded from this study. The study popu-lation was then divided into the following three groups ac-cording to the diagnostic codes and registry data (Figure 1):

ved dental service onal Health Insurance

bilities other than ilities

General populationAll enrollments other than specific and other disabilities

ies, other disabilities, and the general population used in thislth Insurance Research Database for the 2010e2012 period.

Table

1Numberofpatients

withspecificdisabilitiesrece

ivingdentalservicesandave

rage

reim

bursements

foreach

visitfrom

2010

to20

12.

YNumberof

alldisabilities

inTaiw

ana

Numberofall

patients

with

specificdisabilities

inTaiw

anb

Patients

withspecificdisabilitiesrece

ivingdentalservices

Patientnumbers,

n(þ

%)

Visit

numbers,

n(þ

%)

Total

reim

bursements,

n(þ

%)

Ave

rage

reim

bursements

foreach

visit,

n(þ

%)

Ave

rage

reim

bursements

for

each

visitfornorm

al

population,n(þ

%)

Ave

rage

reim

bursements

ratioofpatients

with

specificdisabilities/

generalpopulation

2010

1,07

6,29

311

7,08

828

,374

113,56

716

9,72

3,86

314

94.5

1091

.71.37

2011

1,10

0,43

611

5,93

131

,386

(þ10

.6)

122,79

8(þ

8.1)

193,33

1,62

2(þ

13.9)

1574

.4(þ

5.3)

1099

.4(þ

0.7)

1.43

2012

1,11

7,51

8Notava

ilable

35,524

(þ13

.2)

141,80

3(þ

15.5)

223,99

8,78

2(þ

15.8)

1579

.6(þ

0.3)

1114

.8(þ

1.4)

1.42

aData

extractedfrom

thewebsite

ofDepartmentofStatistics,

MinistryofHealth

andWelfare.(http://w

ww.m

ohw.gov.tw

/cht/DOS/

Statistic.aspx?f_list_n

oZ

312&

fod_list_noZ41

98).

bData

extractedfrom

thereport

ofNationalHealthInsurance

Administration,MinistryofHealthandWelfare.

Dental service use by disabled people 869

1. PSDs: Nine types of disability, namely, limb disorders,autism, chromosomal defects, mental retardation,multiple disabilities, intractable epilepsy, chronic psy-chosis, chronic unconsciousness, and senile dementia.The codes for identifying PSDs were as follows: 00128Cfor severe and extreme disabilities, 00301C for moderatedisabilities, 00303C for mild disabilities, and 00302C formental disorders.

2. Other disabilities: Patients whose registry data indi-cated that they were diagnosed with disabilities otherthan specific disabilities (3 and 7 for severe and extremedisabilities, 2 and 6 for moderate disabilities, and 1 and5 for mild disabilities).

3. General population: All enrollees other than those withspecific and other disabilities.

Quantity analysis

Dental service use was divided into four main categoriesaccording to treatment codes: (1) operative dental treat-ment: amalgam, composite resin, glass ionomer, andcompomer restoration; (2) endodontic therapy: the startand completion of the endodontic session and rubber damusage; (3) periodontal therapy: scaling, subgingival curet-tage, and oral hygiene instruction using a disclosing agent;and (4) tooth extraction: simple and complicated extrac-tion and odontectomy (Appendix 1).

The number of PSDs receiving dental services annuallyand the number of visits and total and average re-imbursements for each visit were analyzed from 2010 to2012. The disabilities of PSDs were subdivided into ninetypes and four levels, and the percentage of dental serviceuse among PSDs and the general population was alsocalculated using the data for 2012.

Quality assessment of dental services

The quality assessment of operative dental treatmentsamong PSDs from 2010 to 2012 included evaluation of therefilling rate in the same clinics, refilling rate in differentclinics, and extraction rate in the same clinics, in com-parison with those of the general population. Moreover, thequality assessment of endodontic therapies included eval-uation of the unfinished rate and extraction rate in thesame clinics.

Results

Table 1 presents the number of PSDs receiving dental ser-vices and average reimbursements for each visit from 2010to 2012. Among all PSDs in Taiwan, only 3e4% receiveddental services each year. The number of PSDs whoreceived dental services increased by approximately 10%every year. The number of visits and total and averagereimbursements for each visit also increased. The averagereimbursement for each visit among PSDs was approxi-mately NT$1500, nearly 1.4 times higher than that amongthe general population.

Table 2 presents patients with nine types of specificdisability who received dental services and their averagereimbursements for each visit in 2012. As many as 70% of

Table 2 Nine types and four levels of disability of patients with specific disabilities receiving dental services and average reimbursements for each visit in 2012.

Types Total disabilities in Taiwana Patients with specific disabilities receiving dental services

n (%) Distribution ofagesb

Distribution ofagesc

Patient,n (%)

Visitnumbers (%)

Totalreimbursements (%)

Average reimbursementsfor each patient

Average reimbursementsfor each visit

Nine typesLimb disorders 381,127

(34.10)1.74 1.61 1.68 6096.1 1735.8

Autism 12,817(1.15)

7.44 7.30 7.53 6375.0 1709.8

Chromosomaldefects

N/A N/A 1.90 1.71 1.70 5647.4 1654.9

Mentalretardation

99,621(8.91)

34.98 34.33 36.34 6549.2 1755.1

Multipledisabilities

114,986(10.29)

34.56 33.27 34.76 6341.7 1732.1

Intractableepilepsy

4549(0.45)

0.39 0.45 0.35 5724.4 1282.7

Chronicpsychosis

119,514(10.69)

16.72 18.92 15.62 5888.4 1368.9

870P.-Y.

Linetal.

Chronicunconsciousness

4129(0.37)

0.23 0.20 0.21 5630.5 1747.4

Senile dementia 39,441(3.53)

2.03 2.22 1.81 5634.2 1354.6

Four levelsMild 430,190

(38.50)7.64 13.16 10.98 10,911.4 1318.2

Moderate 366,173(32.77)

17.96 15.46 13.53 5718.2 1382.7

Severe andextreme

321,155(28.74)

46.64 42.85 47.50 7732.4 1751.1

Mental disorder N/A N/A 27.76 28.54 27.99 7653.7 1549.2

N/A Z not available.a Data extracted from the website of Department of Statistics, Ministry of Health and Welfare. (http://www.mohw.gov.tw/cht/DOS/

Statistic.aspx?f_list_noZ312&fod_list_noZ4198).b Age groups (left to right, in y): 0e2, 3e5, 6e11, 12e14, 15e17, 18e29, 30e44, 45e59, and 60þ.c Age groups (left to right, in y):0e9, 10e19, 20e29, 30e39, 40e49, 50e59, 60e69, 70e79, 80e89, and 90þ.

Dentalservice

use

bydisa

bledpeople

871

872 P.-Y. Lin et al.

patients were classified as being mentally retarded orhaving multiple disabilities, with similar age distributionsfor the age group of 10e20 years, and this proportiondecreased with age. The proportion of patients with limbdisorders, chromosomal defects, intractable epilepsy,chronic unconsciousness, and senile dementia was less than3%. Most patients with limb disorders, autism, and chro-mosomal defects were younger than 20 years of age, andpatients with senile dementia were older than 70 years ofage. Compared with all patients with disabilities, PSDsreceiving dental services were younger.

Table 2 also presents the four levels of disabilities of PSDsreceiving dental services and average reimbursements foreach visit in 2012. A total of 46.64% of patients were classifiedas having severe and extreme disabilities, and the averagereimbursement for each visit among these patients wasNT$1751.10, which was higher than that among the otherthree disability levels. Most patients with moderate disabil-ities were middle aged, and most patients with mild disabil-ities, severe and extreme disabilities, and mental disorderswere younger than 20 years of age. Compared with the age

0 10 20 30

OD

Mild specific disabilities

Moderate specific disabilities

Severe and extreme specific disabilities

Mental disorders specific disabilities

All patients with specific disabilities

General population

0 10 20 30

OD

Mild specific disabilities

Moderate specific disabilities

Severe and extreme specific disabilities

Mental disorders specific disabilities

All patients with specific disabilities

General population

A

B

Denta

Figure 2 Percentages of the four categories of dental servicepopulation in 2012. (A) Percentages calculated by total reimburEndo Z endodontic therapy; EXT Z tooth extraction; OD Z opera

distributions of all disabilities, PSDs with the four levels ofdisabilities who received dental services were younger.

Figure 2 shows the percentage of the four categories ofdental service use among PSDs and the general populationin 2012. Among total reimbursements, dentists claimed37.9% for operative dental treatments, 8.9% for endodontictherapies, 41.7% for periodontal therapies, and 11.5% fortooth extraction for serving PSDs. They claimed 47.0% foroperative dental treatments, 16.4% for endodontic thera-pies, 25.5% for periodontal therapies, and 11.1% for toothextractions for serving the general population. The generalpopulation tended to receive more operative dentaltreatments and endodontic therapies, and PSDs receivedmore periodontal therapies. A similar trend was observedfor the number of visits.

Table 2 lists the treatment quality indices of dentalservices used by PSDs. For operative dental treatments, theteeth of PSDs had a refilling rate of 9.74e15.07%, which washigher than that of 1.39e6.37% among the general popu-lation. For endodontic therapies, the teeth of PSDs had anunfinished rate of 32.03% in the same dental clinics, which

40 50 60 70 80 90 100

Endo Perio EXT

40 50 60 70 80 90 100

Endo Perio EXTl service use (%)

use among patients with specific disabilities and the generalsements; (B) percentages calculated by total visit numbers.tive dental treatment; Perio Z periodontal therapy.

Dental service use by disabled people 873

was also higher than that of 21.42% among the generalpopulation. Tooth extraction rates after operative dentaltreatments and endodontic therapies were similar amongPSDs and the general population.

Discussion

This study used a nationwide population-based insurancedatabase to conduct quantity analyses and quality assess-ments of dental service use among PSDs. The result showedthat PSDs received more periodontal therapies and feweroperative dental treatments and endodontic therapies. Forquality assessments, the teeth of PSDs had a higher refillingrate and unfinished endodontic session rate than the gen-eral population.

This study found that most PSDs receiving dental serviceswere younger (Table 2). This result was similar to that ob-tained in the study by Brister et al6 in 2008; they also usedinsurance claims data to evaluate dental service use amongMedicaid-enrolled adults with developmental disabilities.They found that enrollees younger than 47 years of agetended to use more dental services than older patients withdisabilities. In another study from Taiwan, Lai et al7 alsofound that the use of dental calculus scaling decreased withage among the population with disabilities, according toTaiwan National Health Insurance Research Database datafor the period between 2006 and 2008. This result might bebecause the parents of younger patients would take them toreceive dental services, and older patients were more likelyto be edentulous.6 This also indicated that government anddental experts must establish a more comprehensive dentalcare system to provide more dental services to middle-agedand older patients with disabilities.

This study found that PSDs received more periodontaltherapies and fewer operative dental treatments and end-odontic therapies (Figure 2). The result was comparablewith that of other studies, which focused on dental serviceuse among patients with disabilities in Western countries.Leroy et al8 reported an adjusted relative risk of 0.74e0.84for tooth restorations and an even lower risk of 0.67 forendodontic treatments among adults with disabilitiescompared with the general population in Belgium. Although

Table 3 Treatment quality assessments of dental services amo

Level of disability Operative dental treat

Refilling rate insame clinics (%)

Refilling rate inother clinics (%)

Mild specificdisabilities

5.64 10.55

Moderate specificdisabilities

14.15 19.84

Severe and extremespecific disabilities

10.15 15.04

Mental disordersspecific disabilities

8.14 13.98

All patients with specificdisabilities

9.74 15.07

General population 1.39 6.37

this finding might be because some adults with disabilitieswere edentulous, which could not be confirmed using thedatabase, it is reasonable to suggest that the result reflectsthe high unmet treatment needs of this patient group whenconsidering the higher DMFT and poorer oral health sta-tus.5,9,10 Both operative dental treatments and endodontictherapies are time consuming and require patient compli-ance; therefore, dentists might tend to provide dentalprophylaxis or tooth extraction if patients did not haveobvious symptoms and strong complaints.

To the best of our knowledge, this is the first study inwhich the quality assessment of dental work was conductedamong patients with disabilities. We found a higher refillingrate of 9.74e15.07% for the teeth of PSDs, compared withthat of 1.39e6.37% for the teeth of the general populationduring the 3-year follow-up period (Table 3). Several meta-analyses showed that the mean annual failure rate of resincomposites on permanent teeth was between 1% and 3%under normal circumstances and 3.2e4.6% for the restora-tions in patients at a high risk of caries.11e13 Although sec-ondary caries are one of the major reasons for the failure ofrestorations, the poor oral health status and an impropertooth brushing method might also play critical roles. MostPSDs are unable to achieve independence in activities ofdaily living because of difficulties in cognition, memory,communication, andmanual dexterity; this may lead to poororal hygiene if their caregivers do not properly clean theirteeth.14 With dental plaque accumulation without periodicremoval, secondary caries easily develop around the resto-rations, thereby resulting in a higher refilling rate.

Conversely, this study found an unfinished rate of 32.03%for the endodontic session in the same clinic among PSDs(Table 3). Because PSDs might not be able to complete thetreatment in another dental clinic for their own will, theactual difference in the unfinished rate between PSDs andthe general population might be higher. The objective ofendodontic therapy is to control pulpal diseases and saveinfected teeth by eliminating microorganisms from the rootcanal system. An endodontic session that is started but leftunfinished can create a dead space for bacterial growth,which can opportunistically spread to other body sites,leading to the development of systemic symptoms and evenhospitalization for odontogenic maxillofacial abscesses.15

ng patients with specific disabilities during 2010e2012.

ment Endodontic therapy

Extraction rate insame clinics (%)

Unfinished rate insame clinics (%)

Extraction rate insame clinics (%)

2.22 39.65 2.61

3.69 17.35 2.63

2.24 30.25 2.07

2.48 38.24 1.57

2.57 32.03 2.10

2.50 21.42 1.62

Dental treatment item Treatment code

Operative dental treatmentAmalgam restoration 89001C, 89002C, 89003C,

89101C, 89102C, 89103CComposite resin restorationfor anterior teeth

89004C, 89005C, 89012C,89104C, 89105C, 89112C

Composite resin restorationfor posterior teeth

89008C, 89009C, 89010C,89108C, 89109C, 89110C

Glass ionomer restoration 89011C, 89111CCompomer restoration 89013C, 89113C

Endodontic therapyThe start of endodonticsession

90015C

The completion ofendodontic session

90001C for one-canalsystem, 90002C fortwo-canal system, 90003Cfor three-canal system,90019C for four-canalsystem, 90020C forfive-or-more canal system,90005C for primary toothpulpotomy, 90016C and90018C for primary toothpulpectomy

Rubber dam usage 90012C, 90112CPeriodontal therapyScaling 91003C, 91004C, 91103C,

91104CSubgingival curettage 91006C, 91007C, 91008COral hygiene instructionusing disclosing agent

91014C, 91114C

Tooth extractionSimple extraction 92013CComplicated extraction 92014COdontectomy 92015C, 92016C

874 P.-Y. Lin et al.

In Taiwan, endodontic therapy with or without periapicalperiodontitis is typically provided over multiple visitsinstead of a single visit. Most parents or caregivers mightignore subsequent appointments of the endodontic proce-dure after the symptoms have subsided. An unfinishedendodontic-treated tooth, typically one involving a tem-porary restoration, can increase the risk of contaminationof the oral cavity over time, particularly for patients withdisabilities and poor oral hygiene, leading to bacterialinfection of the root canal system and subsequent apicalperiodontitis when inflammation progresses to the peri-apical tissues. In the Toronto Study,16 the authors foundthat teeth with apical periodontitis had a 3.55-fold risk ofsubsequent endodontic failure.

Behaviors of patients with disabilities, such as poorcooperation, inability to remain motionless and keep theirmouths open, strong grinding of teeth, and severe drooling,make treatment highly difficult and unpredictable.17

Because of the poor oral hygiene of PSDs, we suggest thattreatment guidelines should not be the same as those forhealthy people, and alternative treatment options should beconsidered. Atraumatic restorative treatment (ART), whichinvolves the removal of soft, demineralized tissue with ex-cavators, followed by the restoration of the tooth withfluoride-releasing glass ionomer, has been recommended as apossible treatment protocol for people with disabilities.18,19

In a clinical trial, Molina et al20 compared the survival ratesbetween ART restorations and conventional composite res-torations in people with disabilities. After 1 year, the survivalrate of ART restorations was 97.8%, which was substantiallyhigher than the rate of 90.5% for composite resin restora-tions. Although current evidence for the adaptation ofcertain clinical techniques to the needs of the populationwith disabilities is limited, studies have indicated that theART restoration approach not only improves the experienceof dental treatment among patients with disabilities but alsoreduces health costs and referrals for general anesthesia.

This study has several limitations. First, we used thecode of diagnosis fees and registry data to identify PSDs;therefore, some misclassifications may exist. Dentists con-tracted by the National Health Research Institutes fordiagnosis and treatment require certification; therefore,patients treated by dentists without certification would beclassified as having other disabilities. However, thisgrouping method was stricter, and the misclassificationswere thought to be nondifferential. Second, although thedisabilities of PSDs were divided into four levels (mild,moderate, severe, and extreme), in this study, we believethat severity status of each patient differs even among thespecific levels, and the disability severity of each patient isuncertain in the claims database. Finally, the claims data-base could only be used to investigate dental service useamong PSDs. Without the demand side, we could notdetermine whether the current services can meet theneeds of patients with disabilities.

In conclusion, dental services were accessible to only3e4% of patients with disabilities in Taiwan and were mostlyprovided to younger PSDs during 2010e2012. Quality as-sessments showed that the teeth of PSDs had higher refillingrates and unfinished endodontic sessions than the generalpopulation. We suggest that a more comprehensive dentalcare system is necessary to improve the quality of dental

services, especially in middle-aged and older PSDs. More-over, the treatment guidelines for patients with disabilitiesshould not be the same as those for healthy people, andalternative treatment options should be considered.

Acknowledgments

This study was partly supported by a grant from the Na-tional Health Insurance Administration, Ministry of Healthand Welfare, Republic of China (Grant No. DOH102-NH-1004). This study was based in part on data provided by theNational Health Insurance Administration, Ministry ofHealth and Welfare, Republic of China. The interpretationand conclusions contained herein do not represent those ofthe National Health Insurance Administration, Ministry ofHealth and Welfare, Republic of China.

Appendix 1. Dental treatment items analyzedin this study and the corresponding codes.

Dental service use by disabled people 875

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