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Recurrence of Mandibular MolarFurcation Defects FollowingCitric Acid Root Treatment andCoronaiiy Advanced Fiap Procedures

J. IVlarc Haney DDS MS'Knuf N. Lel<nes, DDS"UtfM. E. Wikesjo, DDS. PhD"'

This report concerns long-term (4 to 5 years) clinicai evaiuation of 22rssoived (compiefs bone ciosure) mandibuiar Ciass 2 turcation defects foi-iowing caronaity advanced flap procedures and citric acid root treatmentwith ar without adjunctive impiantation of freeze-dried, demineroiized aiio-geneic bone. Sixteen buccal furcation sites in i2 patients were avaiiabie torthe foiiow-up evaiuation. The furcation involvement was independently evai-uafed by a pane! of three examiners, each using three turcation index sys-tems. Orai hygiene stanaards. gingivai neatth, probing depth, ciinicai attach-ment ievei, gingival recession, tooth vitality, and detectable caries or rootrésorption were aiso recorded. Mean attachment ievei at the furcatian siteswas 5,8 + 2,9 mm, compared to 4.5 ± 2.2 mm and 3.5 ± 1.3 mm over theprominence af the mesiai and disfal roots, respectiveiy The oiinicai examina-tion further revealed that i2 out ot ió sifes exhibited recurrent Ciass 2 furca-tion invaivement. Of the I ó teetn examined, ane had received endodontictreatment whiie the remaining 15 responded within the normai range topulp testing. One tooth had deveioped caries in the furcation region. Noteeth demonstrated periradicuiar pathology The resuits af this study questionthe iong-ferm sfabiiity of furcation bone regeneratian foilowing coronaiiyadvanced flap pracedures. (int J Periodont Rest Dent 1997; 17:529-535.)

'Graduate Resident, Advanced Educatian Pragram in Periadantics.Lama Linda University, Loma Linda, California.

•'Associate Professai, Advonaed Education Pragrom in Periadantics,Lama Undo University, Loma Linda, Calitornia: and Deportment atPeriadantologv. University of Bergen, Bergen, Norway

•"Professar,, Advanced Educotion Prog rom in Periodantics, Loma Lindauniversity. Lama Linda, Calitarnio.

Reprint requests: Dr Uif M. E. Wikesjo, Genetics institute Inc, One Burtt Rd.Andover, Massachusetts 01810. e-mail: uwikesja@genetics.com

Tooth mortoiify hos been re-ported fo oocur more fre-quenfiy in teefh wifh periodon-tal furcation defecfs fhan Insimiiar feefh wifhouf furcationinvolvement,' Different clinicaltreatments have been sug-gested fo improve the long-term prognosis of fhe toofh.Reoonsfrucfive profooois haveincluded piacemenf of iliaccresf or intraorai aufografts.^""^allogeneic bone,'"^ and aiio-piast implants,'°"^^ or fhe use of

organic' or synthetic barrier

for guided fis-sue regenerafion. iVlembraneprocedures have aiso invoivedfhe adjuncfive use of ailo-geneic bone and bone sub-stitute implants.''*'-''=' Ofherreconstructive protocols havefocused on fiap managementby advoncing and suturing theflap in o coronal posi-ton 13,32,3 ,44-47 voriof ions of thisprotocol have inciuded citricocid root treatment with orwifhouf the adjunctive use offreeze-dried, demineraiized,allogeneic bone implants.

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Buccai Ciass 2 furcationdefects in mandibuior moiorteeth have most commoniybeen used for evaluation of thereconstrucfive protocois; how-ever, maxiiiary and iinguai furca-tion defecfs'3.24,2a,33,3B,39 and

Class 3 defeots have also beensfudied.=3-^5-3''3''ii> Generally,only limited or partial resoiutionof the furcation defects havebeen reported. However, somestudies have reported defectswith complete resolufion asevaluated by turcotion probing,or following reenfry surgeryto assess furcafion bonefjll 7.8.13.19.24,33,30,40,12.45,10

observofions hove usualiy beenmade ó to 12 monfhs post-surgery. Oniy McCiain andSchailhorn'^s hove reporfedlong-ferm (5-year) furcafion clo-sure following reconstructiveprocedures (inciuding mem-brane procedures and bonesubstitufe impianfs). This reporfconcerns the long-term (4 fo 5years) clinical evaluafion of suc-cessfully resoived mandibularClass 2 furcafion defecfs follow-ing coronaiiy advanced flapprocedures.

Method and materials

Twenfy-two buccal mondibularmolar Class 2 furcations, previ-ously reported closed by bonetill following coronaiiy advoncedflap procedures including citricacid root treatment with or with-ouf fhe adjunctive use offreeze-dried, demineralized,ailogeneic bone impianfs,'^"^were fargefed for evaluafion 4fo 5 years fallowing therapy,Sixfeen furcation sites in 12pafients were availabie for eval-uafion. Six furcafion sifes in fourpafienfs were unovaiiable (onefooth had been exfracfed be-cause of endodonfic complica-fions; three patienfs with five fur-cafion sites had moved fromfhe area).

The clinical examinationincluded full-mouth ond furca-fion sife plaque scores,"^ Gin-gival conditions were evaluatedby bieeding on probing, prob-ing depth, and clinical attach-ment Ievei. A force-sensingprobe (Eiectronic PeriodontalProbe, model 250, YeopleResearch) set at 50 g was used.The probe (LL20, Hu Friedy) hada 0,4-mm fip diometer and wascaiibrafed in 1-mm increments.Probings were made af fheprominenoe of fhe mesial anddisfai root adjacent fo fhe fur-cafion sife and direcfly over thefurcofion site along the long oxisof the foofh. Gingivai recessionwas esfimated by subtroctingprobing depfhs from ciinicat

Qtfachment levels. Tooth vitalitywas scored dichotomously ospositive or negative toilowingeiectric pulp (Model 2001 PulpTesfer. Analyfical Technology)ond ice testing. Periapical rodio-grophs were used to screenperiradicular pofhology. Detec-table caries or root résorptionwas diognosed and recorded.Clinicai assessments were madeby one aufhor foliowing initiolcaiibration.

Furcation indexes used

Ali furcofion sites were evolu-afed independenfiy by fhefhree authors occording fo cri-feria defined by Hamp andNyman,^'^ Rateifschak et al,5'ond Glickmon.^^ The degree othorizontal loss of periodontal tis-sue was evaluated on the toi-lowing scale^°:

1. Degree 1 denofes horizohtolloss of periodonfal tissue sup-port nof exceeding one fhirdof the width of fhe footh,

2. Degree 2 denofes horizontalloss of periodonfai tissuesupport exceeding onefhird of fhe width ot thefooth but not encompass-ing the total width of thefurcofion area,

3. Degree 3 denotes horizontal"through-and-through" de-strucfion of fhe periodonfaitissues in fhe furcatioh area.

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The depth of the furcationwas classified as foliows^':

1. Cioss 1: The furcation couldbe probed to a depth of 3mm with the periodontaiprobe.

2. Class 2: The furcation couidbe probed to a depth ofmore thon 3 mm, but wasnot through-ond-through.

3. Cioss 3; The furcation wasthrough-and-through andcouid be probed com-pletely.

The extent of the furcationinvolvement was evaiuatedaccording to Glickman's^^ cri-teria:

1. Grade i involvement (incibi-ent): There wos involvementof the periodontai ligamentin the furcation without grossor radiogrophic evidence ofbone ioss (minimol butnotobie loss of bone in thefurcotion).

2, Grade il involvement: Inthese coses bone was de-stroyed on one or moreaspect ot the furcation, buto portion of the aiveoiorbone and periodontai iigo-ment remained intoct. Theintact periodontoi structuresobstructed complete pos-sage, but partiol penetrationof the turcotion with a biuntprobe was possibie (a vari-abie degree of bone de-struction in the furcation not

extending through the furco-tion to another tooth sur-tace).

3. Grode ill involvement: Inthese coses the bone hadbeen destroyed to suchdegree as to permit thecomplete passage of aprobe through the furcationin o facioiinguol or mesiodis-tai direction: the furcationmay hove been partioiiyoccluded by gingivo (bonerésorption extending tiiroughthe furcation to anothertooth surface).

4, Grade IV involvement; Tiieperiodontium had beendestroyed to such a degreethat the furcation presentedan exposed open areathrough v^/hich a probecould be possed withoutdifficulty (bone résorptionextending through the fur-cation to another tooth sur-face).

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fig la Preoperative radiograph of arepresentative mandibuiar fírst molarfurcotian site.

Fig lb Reentry rodiograph of themandibuiar ñrst molar furcation site.

Fig Ic F:ve-veo' foitow-up rodiographof the mandibuior first molar furcationsite.

Fig Id Clinical photograph at the5-year evaiuatian af the mandibuiarmolar furcation site.

Fig 2 Mean c¡inlca¡ attachment level(AL) and position of the gingivai margin(GM) over the prominence ot themesial and distal roots and aver fhe fur-cotian site.

Results

Figures la fo Ic iilusfrafe pre-operative, reentry, and long-term foiiow-up rodiographs,and Fig I d shows a corre-sponding ciinicoi phofographaf fhe long-term evaiuotion ofo represenfafive furcation sife.Nine ouf of the 16 furcationsites exhibited fhe presence ofsupragingivai plaque. Tweive ofthe 16 sites bled upon probing.The meon full-mouth ploquescore was 44% ± 25%.

Figure 2 presents probingdepth, ciinicai at tochmentIevei, and gingival recessionover the prominence of themesiai and distal roots ond overthe furcation site. Mean probingdepth over the root promi-nences wos 3.3 ± 1.1 mm and2.7 ± 1,1 mm for the mesial anddisfai root, respectively. Ccr-responding ciinicai attachmentIevei vaiues were 4.5 ± 2.2 mmand 3,5 ± 1.3 mm. iVlean prob-ing depth and clinical attach-ment ieveis for the furcotionsites were 4.7 ± 1.8 mm and 5.8± 2.9 mm. respectively. Toble 1presents fhe disfribution of thefurcoficn site assessments. Thescores represent minimumagreement of two out of threeexaminers. In no cose were allexaminers ouf of agreemenf. Allfeeth examined exhibited clini-coily detectobie furcationdefects, and 12 ouf of 16 sitesreveaied recurrent Ciass 2 fur-cotion involvement.

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Of the 1 ó molor teeth exam-ined, one had received endo-dontic treatment, whiie theremaining 15 responded withinnormai range to puip testing.One tooth had developedoaries in the fureation region. Noteeth showed perirodieularpetheiegy

Discussion

This study evaluated clinicallong-term stability of bone clo-sure in mandibular Class 2 furca-tion defects following coronailyadvanced fiap proceduresincluding citric acid root treat-ment with or without the od-junctive use of freeze-dried,demineraiized. aliogeneic boneimplants, Aii 16 moiar teeth evoi-uated exhibited probable buc-cal furcation defects. Twelve ofthe teeth showed Class 2invoivement.

The original furcation de-fects were initially evaluated osclosed with bone foiiowingreentry surgery,'^"^ The presentstudy used ciinicai measures(furcation probing) to assesslong-term treatment outcome.Recently published studies hoveshown that there is no significantdifference between presurgeryand intrasurgery furcation classassessments,^^•^'' When iinearmeasurements have beenused, clinical measurementstend to underestimate the fur-Cdtion bony defect,^^ Theseobservations suggest that clini-

Table 1 Distribution of furcation defect assessments

Degree/Closs/GradeiHomp & Rateitschai<

et ai ^

No detectabie defectDegree/Class/Grode 1 (i)Degree/Cioss/Grade 2 (II)Degree/Cioss/Grade 3 (III)

0790

04

120

03

130

Scores ore based on agreement between two out of ttiree enaminers.

col measures aiso appeor to beappropriate for assessment offurcation bone ciosure.

Apparentiy, the coronailyadvanced fiap procedure didnot provide long-term stableresolution of the furcotion sites inthis study The defects had beensubjected to reentry surgery at12 months foiiowing the coro-neily advanced flap procedureto assess furcation bone ciosure.This intervention may haveImpacted fhe tissue stobiiity,i-iowever, similar gingivai flopprocedures are routineiy usedfor periodontei access surgerieswithout compromising theattochment ievei or causing fur-cotion defects, Possibiy, boneformotion foiiowing periodontalreconstructive procedures moybe more vuinerable to surgicoitrauma than resident bone.

The reestabiished furcofiondefects may hove resultedfrom recurrent periodontoi dis-ease. iHowever, the potientshod received individualizedsupportive periodontai therapyand presented with generaiiyhealthy gingivai conditions. Fuil-mouth plaque soores, however,appeared high. Plaque wasscored dichotomously os being

present or absent following useof a disclosing solution. A thinfilm removable with the perio-dontal probe yielded a positivescore. This registration proce-dure may have overestimatedplaque scores by aiso includingthe ocquired pellicle. The meanpiaque score may thereforenot necessarily be representa-tive of the overall orei hygienestandard for the patient group.Only one patient presentedwith obviously neglected orolhygiene.

In summary, this follow-upstudy couid not provide datasupporting the long-term resolu-tion of buccoi mandibuiar Cioss2 furcation defects followingthe coronolly advanced fiapprocedure. It is suggested thatthis ond other regenerative pro-cedures designed for treatingfurcation defects be subjectedto prospective long-term evoiu-ation under controlled mainte-nance care before being gen-erally accepted.

Acknowledgments

The authors thonk Drs Steven Garrettand Bernard Gontes for identifyingpotients and furcation sites from theoriginai studies.

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