i-.iutiut th'iil t)(iuniiilnt t<>'>fK t2: tTT-tt'rhilrit ill thiimiirti • Atl iii^tiis irsrrvcit

(:ol>\rigtit © i\iiniti\j;nnrd 1996

Endodontics &Dental Traumatology

Management of dens evaginatus: evaluationof two prophylactic treatment methods

Sim Tf C. Management of dens exaginattis: e\afnatieiii of twopre)jihylactic treatment methods. Etidod Dent liatitnatol 1996;12: 137-140. © Muuk.sgaarcf, 1996

Abslracl - Dens evaginaltis (DE) is an ode)nlogenic aneinialycharacteri/.ed fiy au enamef covered tufiercfe, eucfosiug dentinaucf jjulpal lissue. It most coninionly affects premolar teelfi of])eoj3le of lnoiigoloid etliuicil). fhe piexalence of DE in Siiiga-jjore is 2.1%. Fracture or attrition of the ttibercle may lead topuljDal necrosis. Thtis, j^ropbylactic inauagemeut of DE is pre-ferred. A retrospeclive cofiort stucfy couipariug two ce:)nime)njjrojjhyhictic restorative nietbods was condticled. This involved817 children, aged 10 years at the outset, having I .'i9f DE. Tfieteeth were oliserxcd for 2 \ears. The results showed that signifi-cantly less teetli cfevefoped jitiljial j^atholog-) when an enanio-jDfasly-preventive resin restoration method was tised (0.52%) ascompared to an amalgam ca\'it)' restoration (5.37%) and thecontrol (3.65%) [X" = 9.595 (p<().01) df = 2]. Knowledge of tfievarious treatment ojitions and pre\alenc-e data is iniporlanl asifiere is au increasing gfof)af liiigration of jjeopfe of niongoloidetlmicitv.

T. P. C. SimSchool Dental Service, Ministry ot Health,Singapore, Repuhlic of Singapore

Key words: dens-evaginatus: dental abnormality:dental anatomy

Timothy P. C. Sim. Lillian Penson Hall (Room 233),

Talbot Square, London W2 ITT, United Kingdom

Accepted October 3, 1995

Detis e\agitiatits (l^E) is ati odoutogeuic anomalycfiaracterized by an cMianic f covered conicaf tufjer-cle, enclo.sing dentin and pitljDaf tisstie, tnost coiii-moiify fcjuiid on tfie occlusaf surface of perma-nent premolats (Fig. 1). Althotigh rare, similar tu-foercufated strtictures fiave been reported in ifiemolars atid anterior teeth (1). DE is thought to beformed as an abnormal profiferatic^n c:)f ifie inter-nal enamel ejDithelitun leading to an invagiiiatioiiof the internal enamel epithelium and dental pa-pilla into the stellate retictiluni of the enamel or-gan (4). The tubercle averages f.5 mm in diame-ter and 3.0 mm in length (5). Histologic studies bvOefilers (2) fiave sfiown tfie pre.sence of a sfencferpulp horn which extends within the dentin of lhetuf)ercfe. Tfie pufpaf extension may vary from f .f5to 3.2 mm in length and 0.03 to 0.18 nnn in diam-eter (3). Tfie tnfiercle may be large enougfi locatise occhisal interferences, incomplete erujjliou,displacement, rotation and lifting of opposing

teeth (2), and fractute of the tuf)ercle itself. Erac-ture or alirilion e)f the tuf^ercle may lead to pulpalnecrosis, periapical inflammatory responses andloss of vitality in caries free teeth (2). This will ne-cessitate endodonlic proceditres stich as apexifica-tiejn e)f immalnre apices and snfiseqtient ofittna-tion, or renunal of the offending tootfi. Tfiereforelhe prophylactic restoration c:>f these teeth wouldbe the preferred treatment cfioice.

f{\agiuated teetfi occur predoniinautf) iu per-sons of mongoloid ethnicity. The pathogenesis ofDE is uncertain, fjut e\icfence suggest a familial orhereditary pattetti (6-7). The teporled differencesiu iucidence amongst tfie niongofoid sufjgroups,lietween 1.01 % (8) and 4.3% (6), niavsuggest vary-ing degrees of penetrance (6) allhougfi this is dis-puted by Yip (5).

The management of DE is based mainly on em-pirical evidence. A fiieiattire search fVoin 1936show a paucity of coutreiffcnf cfiuicaf trials to CNalii-

137

Sim

Fig. I. A typical c-\amplc- ol ;i ma\illat-y ptc-molat widi dense-vaginatus (ai row).

ale the effectiveness ofclifferenl types e)f treatmentfc5r tfiis anomafy. The literature has lieeu mainlyconfined to single case reports (9-12) and the oc-casional report cjf several cases (3, 13). The ctirric-ttlum of dental schools in this region also show dif-fering treatment pfiilosophies in the managementof Df . Flowever, most of the scliools advocateidentical or variations of the two treatment jjroec--dures evaftiated in this study.

Follc:)wing is a report of a rc-li-e)S]3ective cohortstudy evaltiatiug two common prophylactic restor-ative procecfures used to treat DE, with respect tothe rate of occurrence of j^tilpal and/or periaj^icalsigns and symptoms caused by eaeh lreatment.

Material and method

f-'iglit hundred and seventeen (HI 7) students outof lhe lotal participating jDoptilation of 39,125children, aged 10 years from the otitset, from 3()primary schools, wete fbtuid to have at least e)neDE. Only DE which were asymptomatic and vitalwere included in the study. A total of 1591 premo-lar teeth which met the selection criteria wereincluded iu the sttidy; oul of 1605 DE present. Sixhundred and seventy-nine (679) leetfi wereincluded in the study althotigh they had tubetcleswhich wc-re worn or attritecl as these teeth werevital and asyinpiomatir. There were 14 teelhwhich exhibited se)nie fejrm e)r|Dulpal and/or peri-apical pathe)sis and were excluded. However, dtiete) the lack of iadie)graphie equipment at tfieschool dental clinics, periapical ladiogiaphs cottldnot he taken.

Denial care was provided by denfal ntuses("New Zeafancf" lype) and dentists tcj aff primaryand secondary school children aged 6-18. Assucfi, tfiere were no prololems with rc'S])onse.

fhe children were seen every six months b)' lhedenial nurse aud all patients with ertijDting premo-lars with DE were referred to the dental officer fortnanagetnent. Information from tfie tieatmentcards of these 8f 7 cliildreu was used for the study.De])ending on the lype oi' treatment instituted,lhe Df''. were divided inlo 3 lreatment groups:

TreMvtcitt Grottp A - The tubercle was removedand an occlusal amalgam cavity prejjaralion wascreated, tfie floor of the cavity was lined witfi hard-setting calcium hydroxide, based with zinc-oxide-eugene)l cement and restored with amalgam (afterYcmg-'').

Treatment Group B - Each tubercle was trimmed,the cavity extending only into cfentin. The cavitywas lined with calcitim hydroxide, cleaned andetched. A composite resin was placed to fill tfiecavity and to seal tfie surrouncfing fissures (afterHill and Bellis"). For very large tubercles, a twostage jDrocedure was emjDloyed. fn tfie first stage,only enotigh e)f the ttibercle was trimmed to pre-vent occhisaf tratima. The second stage was com-pleted 3 months later as described abcive.

Treatment (jToup C - (Used as tfie control): Notreatment instiluted. This groujD was confhiedmainly lo jDiemolai's with very small tubercleswhich did uot appear to interfere with the occlu-sion.

Tfie jaatients were reviewed f y the dental nurseevei-y six months for two years fbr every f E. Anyteelh that develojDed signs and/or .symptoms ofjjtilpal e)r periapicaf patfieisis was referred to tfiedental cjfflcer for management and was counted asa faifure of tfiat form of treatment.

The data was tabtilated by treatment grotips andthe ])resence or absence of pufpaf signs ancf syni|>tonis (Table f). The chi-square test for iudejiend-ence for tfnee or more variables was nsed to com-pare statistically the observed projDortions dc vel-o|5ing ptiljDal signs and symptoms, and as lowhether the outcome was depeudeul u|)on lhetreatment.

Table 1. Obseryed Values in the 3 Treatmeiit Groups

Symptomatic'

Treatment Treatment Treatment Totals

A B C (Control) (Rows)

7159 1 11[5.37%] [0.52%] [3.65%]

Asymptomatic** 1039 191 290 1520Totals (Cotutntis) 1098 192 301 1591

X'- = 9.595 (p<0,01)d1=2

* Teeth which developed pulpal signs/symptoms during the observationperiod of 24 inonths

** Teetli which remained free of any pulpal signs/sympfoms during theobservation period

138

Management of dens evaginatus

Results

Oflhe total jjarticipating popttlation of 39125,817students witfi a total e)f 1591 l^E were incfticfed intfie sltidy. Thus the prevalence e>f DE in this serieswas 2 .1%. The prevaleMiee e)f DE in Chinese Siuga-poreaus was 2.6% aud iu Mahns, 0.5%). Tlierewere no DV. ofoserved in fndians and other races.The results were- similar lo that rejjorted by Yip".The projieirtioii e)f the elilfere-nt races seen wassimilar te) the national figure (f4) oi'11.1% (Chi-nese, 14.1% Malay, 7.1%'Indian aud 1.1% otherraces. There was no sex iiredilection. E\ag-iualie)iiwas eibsei-\-ed meist frecjiieutly in niaiicfibularpreuiolars (81.(i%) and were generally preseulf)ifaterally. The mode was 2 DE per child (42.7%)and the range betwe-e'ii f and S DE per cfiifd.

The results e)f the stuch- she)wed lhat 5.37%) iuCiroup A developed pulpal sigus ancf symploniswithin 24 months wliile lhe figure was only 0.52%for Cirouj) B and 3.65%) for Group C ((',outre>l).Talofe f shows the actual observed values.

Iu the chi-square tesl with 2 degrees e)f fieeele)iii,the calculaled observed value \vas 9.595 wliie h isgreater than the critical value 9,210 (a= 0.01).Tfierefbre, there appears to he a siguificaiu differ-ence f^etween treatment grotips A, B and i\ wiifirespects to tlie proportions developing pul|)alsigus and .syniptcMiis. Equivafentlv, tbete appearsto f e a relaliouship between tlie choice of tieat-ment and development of pttlpal pathology.

Discussion

It would a])|:)eai- ihal the more coiisei-\'ati\-ea|5|)rc)ach towards the management of Df\ h\ aloreveutive resiu testoration (Crottp B) tnay be themore appre)i5riate choice when coinj^arecl lo alined, aiiialgani occlusal cax'ity reste)ratioii (C.reiuiiA).

However it must he noted that the j5i'c^|:)orlie)nsdevele)|3iug puf]:)al signs aucf syiii|)toiiis are smaflfor either Irealnienl greiu]). The lenver value of)-served for the control (Ciroup C) |3.t)5%] as coui-]Dared to the jjiojihylaclic ainalgaiii method(Group A) [5.37%)| may be altribuleel te) the fadthai oiil\' small Itibercles whicli did not appear tocause occfusal iiUerrereuces WCMC (iut iu this cate-gory. Moreover, the proj:ilt\laclic amalgani restora-ticjii (Group A) was prefc-rred by operators h\ a ra-tio of 2.2: 1 conijjared to the olher two gi-oiij)s andthis may fiave fiacl an inllueuce ou ifie result.

There have been many alteinalixe trealittenlnietfiods prope)sed to niauagc DE. f^a/.an (f5) liasaltein]3ted to stippori the tubercle with a li.ssurc-sealant. This was to alfo\v l)oth the- material and

the tubercle- to abrade sle)wfy witfi time encourag-ing foi nialiou of seccjiidary deiiliu; aftfiougfi thishas been shown by Oehlers to he itnieliafile (16).fiazan, in tfie same paper, fater reconiniended tfietise of a ceMiiposite resin instead of a fisstne sealantfor improNed sireiiglh. This method ajajieais to heimpractical es]:)ecially in leetfi witfi large tuberclesas tfic" occftisal build-np of couijiosite resin wouldcreate occlusal iuterferences with opposing teeth.

A survey h\ fiedi (f 7) shows that 27% of dentistsin Hong Kong tise the nielfiod desc rified h\ ^c)ng(3). A fufl 67% of ifieni prefer ifie nielfiod of "ju-dicious grinding of the tubercles" (16) at periodiciutervafs soon after tootli eriqjtion lo enconragesecondary cleiuin foruialion aiie;l obliteration ofthe pulpal chamber within the tul^ercle (17). Thelilerattire appears to be against lliis lecfinic]tie (f),(17, 18, 19).

Otlier niethods stufi as efective root canal ireat-lneiit iiia\- be coiiiplicaied b\ immature apices anditieeinipfete root foruialion necessitating apexifica-tion i)rocediu-es wilfi calcium fiycfroxicfe. filecli\ereincnaf of ifie affected tootli sliould otih- he con-sidered in conjuuciiou with orihodontic lhera|j\-.

1 he results of this sttid\' sfiottld encotirage thewider acfoptiou of the selective euamopfast\--pre-\-eiiti\-e resin resloratixc uielliod as a viafife wa\' lomanage cfens exaginaUis.

f\.iie)\vledge of ifie Narious treatineiU modalitiesand prc'Nalence data for dens evaginatus is iiiipor-tanl as there is an iticreasing global niigratiein ofj)cH)|ife e)l inoiig<)le)id c-tliiiicit)\ f he more recentcase reports afiont dens evaginaltis have origi-nated fi-om the West. .Aff of these fia\e fjeeii onthe uianageinent of this anouialy in Asian iiniiii-grant populations (9-12).

Summary and conclusions

fleus e\-agiuatus w.is found in 2.f % of chilcfreii inSingapore. There was a racial predilection fe)i- j^er-se)ns eif iiU)iigofoid etliuicilv-.

A retrospective coluirt stuch' cotujjariiig twoce)iiinu)u pre)plnlaclie- reste)i-ati\-e liiethods fbriiiaiiagiiig cfens cwagitiattts was done involving 817children, aged 10 vears at ifie e)utset, with a te)tal e)f1591 leelh having tliis aitoinal\-. The leeth vvet-ee)bser\-eel leii 2 ^-c'ars.

Tlie restilts sliowed lltat sigiiificanlh' less teellicfc-vefopecf pulpal signs aud SNniptoiiis when a sc--lec'lixe euaiiioj)lasty-pre\-enli\-e resin resloratixeuu-thod was used (().52%i) as compared to theanialgatti cavilv restorative method (5.37%) andthe control (3.65%), [x" = 9.595 (p < 0.01) df = 2]

Knowledge of the vaiiotis treattnent optionsand [irevaleMice data le)r clcMis eNagiiiatus is impor-

139

Sim

tant as tfiere is an increasing migration of peojjlewith a predilection for tliis anomaly to many partsof the world.

Aeknowledgements -The author would like te) thanktfie cfentaf therapists and ntirses fre)in tfie Jtiroug/Cifementi and Hotigang/Serangoon/Aiig Mo Kiogroups of school dental clinics feir tfieir help incollecting the data and reviewing the patients in-volved in the study.

References

1. LAI' VC. Odonlonu-s oltlie- axial core- lype-. tlrDent / 105:");99.- 219-25

2. Ot.itt.KRs FAC. 71ie- Itibc-rc ulalc-d pie-molai-. Dent Prae DentRee 195(5; 6; 144-8

?K Yc)N(. .SL. I't-ophylaelir tte-atme-nt ofde-ns e-va^nnalns. ASDCI Dent Child 1974; 41:289-92

1. IRAIMAN liK. Au tiure-e:ot-de"d Ibrni ol the- simplest type- olthe- dilated re)mpe)sile odoutome. BrDent/\949; A'6.-271—5

.5. Yii' WK. The prevalence of dens evagitiattts. Oiat Surg OralMed Oral Pathol 1974; 38: 80-7

(). Mi.KRit.i. RC;. Occlusal anomalous inbetxles on ptemolarsof Alaskati t^skimos aud ludiaus. Oral Sing Orat Med OralPathot\9Ci4: / 7.-484-96

7. PRIDDYWI., CARIKR HC. At -/.t\'s J. Deiis Evaginalus-an anom-aly with clinical sisTnillcauce. /lunloitim 197(1; 2.-51-2

8. Ri:ic:iiARi P. TWIINIRW I). l)e-us c-vaginaltis in Ihe- Thai. Ane-valiiation ol liriyone- casc-s. Orat Sing Oral Med Oiiit Pathot1975; J9.-()1.5-2r

9. M< ALLAN l . I l , n iKi i nos PA. D e n s Evaginal t t s . C^asc- Re-port.

Anst Dent I \989\ 34: V.W-\l(t. .SiiAV JC. D e n s evaginat t t s ; case- t e p o t t of a succc-ssl'til Ire-al-

meul. IFndodon 1984; 10:324-61 1. H I L L 1*'J, BI:LLIS W J . D e n s evagin.i t t is a n d its m a n a g e - m e n t .

Br Dent I \984\ 156:400-212. CIKLSI J R . D e n s Kvaginat t is . ( ' ase re-port a u d ic-\ic-w ol ihc-

lite-raliit-c-. Orat Surg Oral Med Oral Pathol 1989; 6 7 ( 5 ) ; (128-

3\

I!'). I.IM S T, Yot NC. SI.. (liiiN Ml.. A revic-\v ol |ji-oph\laxis Ire-al-meut ol dens e-vai^inattis. / //;/ .\ssoe Dent Child 1982; 13:21-5

14. LAt KE. Sitigapotx- census ol po|3ttlatioti 1990; Rc-lit;ion,cliildcare aud leistite activities. Census of Population Offiei'.Dept. of Statistics. Siugapore, 1994.

15. BAZAN M T . DAWSCIN I.R. Prejteetion oldc-ns e-\-aginatus wilhpit aud fissure- sealaul. ASDC/Dent Chiht 198:5; 5fA- :i()l-:!

U). OKIILLRS I'A( i, 1,I:L KVV. I.IK. K( i. Deiis evagiualtis (evagi-ualed odonlonic-) Its striic line- aud tespouse-s lo e-xlc-tiialslimttli. Dent Prae Dent Ree 1967; //.- 239-44

17. Bt.ni R. PUTS N B . Deus evaginattts in the llotig Kong Chi-nese poptilation. I'/ndodDent 'Prauinatot 1988; 4: 104-7

18. Ri.,ic;iit;tfi- PA, Mt lAii D, SIIVVSLM M . Moiphologic Iindingsin dens evagiuatus. //)/ / Oreit Surg 1982; / / ; 59-63

19. Goic) T. KA\VAIIARA K, KoNnen T. IMAII K, Kisiii K. Ft |IKI Y.

(Iliuical aud radiological stttely of deus evagiuattts. Dm-tomaxillofae Radiol 1975; ,S'.- 78-83

140