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The Lincoln dental caries study: a three-year evaluation of dental caries in persons with various mental disorders Arnold D. Steinberg, DDS, MS, Chicago Stuart Zim m erm an, PhD, Houston
An evaluation o f three-year incremental caries scores in
institutionalized persons with various mental disorders indicated that in a DMFS evaluation o f caries increment, the group with Down syndrome had significantly few er caries than many o f the other groups compared. No such significant difference was found in an evaluation of DMFT. The caries increments did not differ significantly from one another in all other mentally subnormal groups. The carious lesions in the group with Down syndrome appeared to be limited to the occlusal surface.
T
M he m ajority of reports agree that the prevalence of dental caries among m entally subnorm al (MS) per sons is low er than am ong normal persons. A lthough G u llik son 1 re ported high er caries scores in re tarded ch ild ren than in norm al c h il dren, the m ajority of studies have re ported a low er prevalence of caries for both institu tion alized and non institu tionalized M S persons than for norm al persons of sim ilar ages.2'6 W ithin the M S population, several in vestigation s7'9 have show n low caries scores in those w ith Down syndrome. However, Sw allow 10 re ported an overall caries sim ilarity be tw een those w ith Down syndrom e and M S persons w ithout Down syn drome. A ll of the studies reported caries
scores from a single exam ination. T h ey w ere not based on yearly in crem ental caries scores that provide a m ore accurate appraisal o f caries. In a previous in vestig ation ,11 we ob served that the overall incid ence of caries (based on one-year increm en tal caries scores) in an in stitutionalized M S population w ith out Down syndrom e was not sig n ifi cantly different from the caries in c i d ence of a noninstitutionalized, norm al population of sim ilar age. W hen one exam ination of prevalence of caries (DF and DMF) was made, the prevelance was significantly lower in the M S population; this supports the data o f other investigators.2'6 In the previous stud y,11 we inves tigated the d ifferences betw een an institu tionalized M S population and
a noninstitu tionalized norm al popu lation. No attem pt was made to inves tigate possible differences in in ci den ce of caries betw een the sub groups (arranged according to m en tal disorder) of the M S population. As it is possible that those w ith a sp ecific disorder may have a low in cid en ce of caries even though the overall M S population does not, we evaluated the in cid en ce of caries in institu tionalized persons w ith vari ous m ental disorders based on three-year increm en tal scores.
Study methods A total of 250 M S, institu tion alized , m ale and fem ale persons (who formed the control group for a bottled-beverage study cond u cted at the L in co ln State S ch oo l in L inco ln, 111) w ere exam ined in itia lly .12 T h eir ages ranged from 10 to 21 years, w ith a m ean age of 16.8 years, and they w ere exam ined at six-m onth inter vals for three years. T he in stitu tion classified the patients according to m ental disorder, and we retained this classificatio n . The entire in stitutionalized population was de fined as m entally subnorm al (M S). T hose patients who prim arily had a defect in in tellig en ce existing sin ce birth, w ithout an organic brain dis order of know n prenatal cause, were subclassified as m entally retarded. JADA, Vol. 97, December 1978 ■ 981
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Another subclassification, chronic brain disorders, was defined as or ganic brain disease, usually of known causes. Any classification with fewer than eight subjects re maining at the end of three years was not considered so that a meaningful base for statistical evaluation could be provided; nine groups were eval uated in this report. As control sub jects in the bottled-beverage study, each person included drank 12 oz of water each day under supervision, besides the water that was normally consumed. The fluoride concentra tion of this water was 0.4 ppm. A detailed account of examination and recording procedures and other related information has been pub lished previously.12All data were ob tained from both oral and radiographic examinations and statisti cally evaluated by analyses of vari ance. Differences between means were determined by the Duncan Multiple Range procedure. In an effort to better assess factors
Table 1 tion.
responsible for teeth lost during the course of the study, every tooth that was extracted during the three-year period was noted, and records were checked for indications of caries at the examination immediately before extraction. If the tooth was carious on two or more surfaces or severely cari ous on one surface, the loss was at tributed to caries. If the tooth had no active caries or (as in a few instances) had only slight caries involvement of a single surface, it was considered lost because of other causes. The data presented in Table 1 for our threeyear increment DMF scores are based on only those teeth believed lost be cause of dental caries.
Results At the first examination, the group with Down syndrome, who were sig nificantly younger, had fewer teeth and more unerupted teeth than the other groups (P<.05; Table 2). Other groups did not differ significantly from one another. In both the mean
DFT and DFS evaluations, the group with Down syndrome had a significantly lower caries score than all other groups, except those in the classification of congenital cranial anomaly. Using a mean DMFT com parison, the group with Down syn drome had a significantly lower caries score than five of the other eight groups. In these comparisons, none of the other groups differed sig nificantly from one another. No sig nificant differences in caries scores could be observed between any group when a DMFS comparison was made. Three years later (Table 1), the mean number of teeth present did not differ significantly between any of the groups. The group with Down syndrome had a significantly greater number of unerupted teeth than five of the eight other groups and had a significantly lower average age than four of the eight other groups. None of the other groups differed signifi cantly from one another. The mean
Dental caries in persons with various mental disorders, third-year examina-
Mental subnormality No. of Unerupted Incremental Incremental classification Age teeth teetn DMFT No. DMFS Chronic brain disorder Congenital cranial anomaly 9 18.9 ± 4.3 25.3 ± 4.5 1.1 ± 3.0 2.0 ± 2.7 2.5 ± 3.0 Down syndrome 1.2 ± 2.0 17 17.1 ± 3.4 21.3 ± 4.9 2.4 ± 4.1 1.5 ± 2.4 Birth trauma 18.6 ± 4.5 8 25.2 ± 3.3 0.6 ± 1.4 2.1 ± 2.4 3.5 ± 3.9 Idiopathic epilepsy 1.9 ± 2.3 9 19.8 ± 3.5 22.9 ± 5.7 0.9 ± 2.7 7.8 ± 7.5* Unknown causes 18 18.7 ± 3.1 25.4 ± 2.9 0.1 ± 0.2* 3.8 ± 3.6 7.7 ± 6.9* Mentally retarded Familial IQ 50 to 69 13 20.5 ± 2.7* 24.4 ± 4.8 0.0 ± 0.0* 3.4 ± 2.4 8.1 ± 6.1* IQ less than 50 15 20.8 ± 2.9* 24.6 ± 3.8 0.2 ± 0.6* 4.2 ± 3.2 8.7 ± 7.4* Idiopathic IQ 50 to 69 16 20.5 ± 3.1* 24.6 ± 4.3 0.2 ± 0.4* 3.3 ± 4.6 8.4 ± 8.9* IQ less than 50 10 20.4 ± 3.7* 23.7 ± 2.9 0.0 ± 0.0* 1.7 ± 1.8 5.0 ± 6.2 Total 115 19.4 ± 3.5 24.1 ± 4.3 0.6 ± 2.1 2.8 ± 3.1 6.1 ± 6.7 All values are means ± standard deviation. ‘ Significantly different from Down syndrome group P<.05, as determined by using analysis of variance and the Duncan Multiple Range test.
Table 2 ■ Dental caries in persons with various mental disorders, initial examination. Mental subnormality No. of Unerupted classification teeth teeth DMFT DPT No. Age DMFS DFS Chronic brain disorder Congenital cranial anomaly 12 16.2 ± 3.8* 23.5 ± 5.4* 3.1 ± 5.7* 3.8 ± 4.2 2.4 ± 2.7 9.8 ± 12.6 3.2 ± 3.9 Down syndrome 0.4 ± 1.0 35 13.9 ± 3.1 18.8 ± 5.8 7.1 ± 6.1 10.7 ± 12.1 0.4 ± 1.0 2.5 ± 2.7 Birth trauma 20 16.6 ± 3.9* 24.5 ± 4.0* 1.8 ± 4.0* 4.8 ± 5.1 3.1 ± 3.4* 12.3 ± 14.7 4.1 ±' 4.5* Idiopathic epilepsy 16 17.3 ± 3.4* 24.4 ± 4.7* 1.3 ± 4.0* 6.3 ± 6.1* 3.9 ± 3.4* 17.3 ± 21.5 5.4 ± 5.9* Unknown causes 41 16.4 ± 3.9* 24.8 ± 3.8* 0.9 ± 2.0* 7.3 ± 5.8* 5.1 ± 4.2* 18.1 ± 10.7 7.0 ± 6.5* Mentally retarded Familial IQ 50 to 69 31 17.7 ± 2.9* 24.7 ± 3.6* 0.2 ± 0.7* 7.8 ± 6.1* 4.7 ± 3.7* 21.6 ± 21.0 6.5 ± 6.4* IQ less than 50 24 18.3 ± 2.1* 26.0 ± 3.0* 0.3 ± 0.7* 5.1 ± 4.6 3.4 ± 3.4* 12.5 ± 15.5 4.2 ± 4.5* Idiopathic IQ 50 to 69 43 17.8 ± 2.5* 25.3 ± 3.4* 0.9 ± 2.9* 7.6 ± 6.7* 5.9 ± 5.0* 17.7 ± 15.8 8.2 ± 8.3* IQ less than 50 19 16.5 ± 3.3* 24.6 ± 3.9* 1.2 ± 3.2* 5.9 ± 5.1* 3.7 ± 3.8* 16.4 ± 17.2 5.4 ± 6.6* Total 241 16.8 + 3.2 24.0 + 4.6 1.9 + 4.1 3.9 + 4.0 5.9 + 5.5 15.8 + 17.0 5.2 + 6.5 All values are means ± standard deviation. •Significantly different from Down syndrome group P<.05, as determined by using analysis of variance and the Duncan Multiple Range test. 982 ■ JADA, Vol. 97, December 1978
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caries scores as m easured by the in crem ental D M FS indicated that only the group w ith Down syndrom e had a sign ifican tly low er caries in cre m ent, w h ich was different from five of the eight other groups. However, an increm en tal D M FT evaluation did not show sign ifican t differences in caries increm en t betw een any of the groups. T hose who rem ained in the study after three years w ere not dif ferent in any way we m easured from those in the m uch larger group who w ere exam ined at the outset.
Discussion and summary At this institution, the patients re ceived a well-balanced diet with between-meal snacking and refined carbohydrate intake similar to a noninstitutionalized population.12 The patients received their meals from a central kitchen, and the result ing uniformity of diet makes this variable of minimum importance. T h e sig n ifican tly low er average age of the patients w ith Down syn drome cou ld accou nt for the few er num ber o f teeth present and the greater num ber of unerupted teeth (Table 2). However, in com parisons o f the group w ith Down syndrom e at the initial exam ination (average age o f 13.9 years) and at th e three-year exam ination (average age of 17.1 years) w ith sim ilar age groups from a normal population, the norm al c h il dren had a sign ifican tly greater num ber of teeth present and a sig nif icantly low er num ber of unerupted teeth .11 M osier and others13 observed that in a M S population, many per sons have a generalized delayed som atic growth that could account for delayed eruption of teeth. The low m ean num ber o f teeth in the group w ith Dow n syndrom e may be the result of not only the younger age, but also of delayed eruption and the early loss o f teeth from the re ported high in cid en ce of periodontal d isease.14 During three years, ap proxim ately 95% of teeth m issing in the group w ith Down syndrom e were lost becau se of factors other than den tal caries (54 of 57 teeth) com pared to only 38% of m issing teeth in this cat egory (69 o f 182 teeth) in other M S
groups.12 At our in itia l exam ination (Table 2), the group w ith Down syndrome had a low prevalence o f caries (as indicated by D M FT, D FT, or D FS), a finding in accord w ith previous re su lts.7-9 How ever, the D M FS scores did not indicate that the group with Down syndrom e had a significan tly low er caries score. T h e use of DMF scores in the population w ith Down syndrom e is of questionable value as the m issing factor (“M ” in the DMF notation) is not w eighed equally w hen this population is com pared w ith another. A ll the scores represent only previous dental exp erien ces as they are based on a sin gle exam ina tion. T he use of the scores m ust be questioned in th is type of evaluation as th e few er num ber of teeth in the m outh of the patients w ith Down syndrom e p laces few er teeth or sur faces at risk and may be responsible for the sig n ifican tly low er caries scores. The three-year increm en tal caries scores, as evaluated in T able 1, give an accurate appraisal o f caries for the various M S groups. M ean DMF scores are given here becau se the m issing factor in these com parisons is an indicator only o f teeth m issing as a result of dental caries. In these evaluations, although the group w ith Down syndrom e had the low est caries in crem ents, they were not sig n ificantly different from the caries increm ents of any of the other groups w hen increm ental D M FT scores were used, but were sig n ifican tly lower than five of the other eight groups in an increm ental D M FS com parison. The sim ilarity of the increm ental
D M FT scores in Table 1 and the id en tical m ean D FS and D FT scores in T able 2 indicate that in th e group w ith Down syndrom e, caries appears to be lim ited to a single surface per tooth. Furtherm ore, a “m ap p ing” of D and F com ponents from T ab le 1 by surface and location in the m outh show ed that in the group w ith Down syndrom e, caries was lim ited prim ar ily to the occlu sal surface of the post erior teeth. S u ch results suggest that these evaluations of D M FS in cre m ental scores are m eaningful. Our results support previous fin d in g s7'9 and indicate that the group w ith Dow n syndrom e had the low est caries increm ental score. However, there were several other M S groups that also had low increm en tal D M FS caries scores that were not sig n ifi cantly different from those of the group w ith Down syndrom e (co n genital cranial anom aly, birth traum a, and m entally retarded idiopathic IQ of 4 9 and less). The finding of a sign ificantly greater num ber of unerupted teeth in the group w ith Down syndrom e as com pared to m any of the other groups (Table 1) can only serve to enh ance the d issim ilarity in in cid en ce of caries. T h e in cid en ce o f caries in none of the M S groups differed sig n ificantly from one another in either increm ental D M FT or D M FS com parisons.
This investigation was supported by a grant from the Illinois Bottler’s Association through the auspices of the Illinois State Dental Society. T he authors thank the staff of the Lincoln State School, whose assistance made this proj
THE AUTHORS Dr. Steinberg is professor, department of periodontics, College of Dentistry, University of Illinois at the Medical Center, 801 S Paulina St, Chicago, 60612. Dr. Zimmerman is affiliated with the department of biomathem atics, M. D. Anderson Hospital, University of Texas, Houston. Address requests for reprints to Dr. Steinberg.
STEINBERG
ZIMMERMAN
Steinberg-Zimmerman : DENTAL CARIES IN PERSONS WITH VARIOUS MENTAL DISORDERS ■ 983
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ect possible, and Dr. W illiam Greek for his long-term support. 1. Gullikson, J.S. Oral findings of mentally retarded children. J Dent Child 36:133 MarchApril 1969. 2. Ellis, R.G. Dental infection and mental health. Oral Health 33:711 Dec 1943. 3. Snyder, J.R.; Knopp, J.J.; and Jordan, W.A. Dental problems of non-institutionalized men tally retarded children. Northwest Dent 39:123 M arch 1960. 4. Boyd, J.D., and Cheyne, V.D. Epidemio logic studies in dental caries; incidence of caries among institutionalized children. J Pediatr 31:306 Sept 1947.
5. Tannenbaum, K.A., and Miller, J.W. Oral conditions of the mentally retarded patient. J Dent Child 27:277 Fourth quarter 1960. 6. Toth, K., and Szabo, I. Elme-es idegbetegek fogcaries viszonyai. Fogorv Szemle 56:293 Oct 1963. 7. Winer, R., and Cohen, M.M. Dental caries in mongolism. Dent Prog 2:217 April 1962. 8. Johnson, N.P.; Young, M.A.; and Gallios, J.A. Dental caries experience of mongoloid children. J Dent Child 27:292 Fourth quarter 1960. 9. Winer, R., and others. Dental treatment of the mentally subnormal. Bull Acad Dent Hand icap 1:9, 1962. 10. Swallow, J.G. Dental disease in children with Down’s syndrome. J Ment Defic Res 8:102 June 1964.
11. Steinberg, A.D. A comparative study of caries in m entally subnormal and normal indi viduals. Proceedings of the First International Congress on Dentistry for the Handicapped, At lantic City, NJ, Oct 1971, pp 1-5. 12. Steinberg, A.D.; Zimmerman, S.O.; and Bramer, M.L. The Lincoln dental caries study. II. The effect of acidulated carbonated bever ages on the incidence of dental caries. JADA 85:81 July 1972. 13. Mosier, H.D., Jr.; Grossman, H.J.; and Dingman, J.F. Physical growth in mental defec tives. A study in an institutionalized popula tion. Pediatrics 36:465 Sept 1965. 14. Cohen, M.M., and others. Oral aspects of mongolism. Periodontal disease in mongolism. Oral Surg 14:92 Jan 1961.
Foley’s Footnotes T h e slo w d e v e lo p m e n t o f th e p ro v isio n o f d e n ta l se rv ic e s in th e A r m y o f th e U n ite d S ta te s is a n in te re stin g b u t a lso sh o c k in g story. D u rin g th e 19th c en tu ry , th e m e d ic a l m e n a ss ig n e d to v a rio u s e le m e n ts o f th e A r m y w e re lo o se ly r e s p o n s ib le f o r th e h a n d lin g o f d e n ta l e m e r g e n c ie s su c h a s to o th a c h e s a n d f r a c tu r e d ja w s . T h e in fo r m a tio n I sh a ll p r e s e n t in th is “F o o tn o te ” p r o v id e s a fir s t-h a n d r e p o rt on c e r ta in p h a s e s o f h e a lth c a re r e la te d to d e n tistry . T h e so u rc e is F iv e Y e a rs a D ragoon (1906), a h ig h ly r e g a r d e d b o o k b y m ilita r y h isto ria n s, in w h ic h P e r c iv a l L o w e te lls o f h is e x p e r ie n c e s w ith th e F irst R e g im e n t o f D ra g o o n s on th e G rea t P la in s, fr o m 1849 to 1854. T h e A rm y’s n e g lect o f the h ealth needs o f its W estern so ld iers is clearly in d icated in th ese observations by Low e: “T h e p rin cip al m ed icin es in the M ajo r’s ‘c a se ’ w ere opium , salts and q u inine.— In m y w hole five years of serv ice w h ile on the p lain s, every sum m er on a long cam paign, liab le to battle and alw ays exp ectin g it, we n ev er had a d octor.” T h e d iet o f th e cam paign ing solders as reported by Low e w as certain ly no t co n d u cive to the m ain ten an ce of good h ealth: “W e lived for six m onths at a tim e on bread, rice, beans— no other cereals and no vegetables— a little sugar and coffee, b acon and su ch gam e as could be k ille d .”
The kind of wound suffered by an Irish trooper suggests a query as to the probable incidence of such wounds received by the soldiers in their battles with the Indians. “O’Meara had been wounded in the battle of the Blue in the fall of 1849, losing two front teeth knocked out by an arrow that cut his lip badly.” T h e episod e o f the com ing to Low e’s com pan y of a recru it w ho an ticip ated th e need for dental serv ices by h is fello w hussars illu strates the early stage o f d entistry all over the O ld W est: th e casu al operator w ho cam e w est w ith on e or tw o d ental instrum ents w ith th e in ten t of profiting from the absen ce of trained d entists by perform ing extraction s on usually d esperately w illin g v ictim s. “One of th e recru its from C arlisle, Pa, w as a tall fin e-lo ok in g , rather p olish ed m an, w ith a fin e set of d ental instrum ents, and proved to be a fin e w orkm an.” T h is “ p o lish ed ” ind iv id u al w as a “sm art op erator” in m any w ays. A fter a y ear in th e service during w h ich he be cam e first sergeant of a cavalry troop, th e “ d en tist” deserted, taking w ith him horses and equ ipm ent, plus com pan y funds. Near Jefferson City, M o, th e fu g itive sold ier m urdered and robbed the c h ie f en gin eer of the M issou ri P a cific Railroad. A fter several trials, th e deserter w as hanged. T hu s w as lost to the W est a m an who m ig h t have becom e acclaim ed as a p ion eer p ractitioner. G a rd n e r P. H. Foley
984 a JADA, Vol. 97, December 1978