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Horizontal ridge expansion and implant placement using screws: a report of two cases

Young-Kyun Kim1,2, Su-Gwan Kim3

1Department of Oral and Maxillofacial Surgery, Section of Dentistry, Seoul National University Bundang Hospital, Seongnam, 2Department of Dentistry and Dental Research Institute, School of Dentistry, Seoul National University, Seoul,

3Department of Oral and Maxillofacial Surgery, School of Dentistry, Chosun University, Gwangju, Korea

Abstract (J Korean Assoc Oral Maxillofac Surg 2014;40:233-239)

Implants are typically placed after performing ridge expansion by inserting screws of gradually increasing thickness and good clinical outcomes are often obtained. We placed 11 implants in 6 patients, and one implant failed during osseointegration but it was replaced immediately after removal and successful prosthetic treatments were completed. During these surgeries, buccal cortical plate complete fractures do not occur. Inserting screws for ridge expansion is a successful and predictable technique for implant placement in narrow alveolar bone.

Key words: Dental implants, Alveolar ridge augmentation, Bone screws[paper submitted 2014. 7. 3 / revised 2014. 8. 7 / accepted 2014. 8. 14]

separationofthebuccolingualboneduringsurgeryarepo-

tentialrisks,soitiscrucialtominimizethesecomplications.

Methodsaugmentingthealveolarbonetothebuccolingual

sideareoftendonebecauseridgesplittinginvolvingtheuse

ofanosteotomeandmalletcaninducegreenstickfractures

ofthebuccalcorticalbone.Intheridgesplittingprocedure,

discomforttopatientsisoftensubstantialbecauseofmallet-

ing,andthereisariskofbuccolingualbonefracturewhen

excessiveforceisdelivered.Therefore, thepresentreport

introducesandevaluatestheclinicalresultsofaprocedure

thatexpandstheridgeinastepwisetechniqueusingscrews

ofgraduallyincreasingwidth.

II. Cases Report

Thisstudywasperformedafterobtainingapprovalfrom

theinstitutionalreviewboardoftheSeoulNationalUniver-

sityBundangHospital(No.B-1007-105-106).Inthedepart-

mentoforalandmaxillofacialsurgery,oneoralandmaxil-

lofacialsurgeonperformedridgeexpansionsfromMay2008

toSeptember2009.Theprocedurewasperformedusingex-

pandingscrews(SplitMaster;Mr.Curette,Seoul,Korea),and

implantswereplacedsequentiallyorsimultaneouslyin6pa-

tients(1maleand5females).Theageofthepatientsranged

from31 to69yearswithameanageof55.1years.One

I. Introduction

Manycasesofimplantplacementinvolveinsufficientbuc-

colingualwidthoftheedentulousridge.Themethodsused

toresolvethisissuearethefollowing:narrowimplantplace-

ment,horizontalveneerblockbonegraft,horizontalguided

boneregeneration(GBR),andtheridgesplittingprocedure1-3.

Ridgesplittingisappliedprimarilyincaseswherethebone

heightissufficient,butthewidthisnarrow.Thepurposeof

ridgesplittingistowidenthealveolarridgebytakingadvan-

tageoftheelasticityofbones,anditisfrequentlyperformed

intheanteriormaxillomandibulararea.Thissurgeryrestores

themorphologyofthelingualsideofthealveolarboneand

obtainsnotonlyaestheticresults,butalsoahousingeffect

exertedbythecorticalboneofthebuccolingualside,which

improvestheosseointegrationofimplantsbyprovidingan

amplesupplyofbloodcirculation4.Nevertheless,fractureand

CASE REPORT

Su-Gwan KimDepartment of Oral and Maxillofacial Surgery, School of Dentistry, Chosun University, 309 Pilmun-daero, Dong-gu, Gwangju 501-759, Korea TEL: +82-62-220-3815 FAX: +82-62-228-7316E-mail: sgckim@chosun.ac.kr

This is an open-access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licenses/by-nc/3.0/), which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited.

CC

Copyright Ⓒ 2014 The Korean Association of Oral and Maxillofacial Surgeons. All rights reserved.

http://dx.doi.org/10.5125/jkaoms.2014.40.5.233pISSN 2234-7550·eISSN 2234-5930

J Korean Assoc Oral Maxillofac Surg 2014;40:233-239

234

sions,amaxillaryliftsurgerywasperformedsimultaneously.

Atotalof11implantswereplaced:5inthemaxillaryante-

riorand3inthemaxillarypremolararea.(Table1)Complica-

tionsduringsurgery,suchasbuccalcorticalplatecomplete

fracture,didnotdevelopwiththeexceptionofsevereedema

andpost-surgicalecchymosisinonecase.Inthatcase,osseo-

integrationfailurewasobserved4monthsafterthefirstsur-

gery,sotheimplantwasremovedandwasreplacedimmedi-

ately.Wounddehiscencedevelopedafterimplantplacement,

andtheimplantwasconsideredapossibleetiologicfactor.

Afterapproximately8weeksafterreplacement,afixedpar-

tialprosthesiswasinstalled.Duringthefollow-upobserva-

tionperiod,averaging44.7months,all6patientsmaintained

normalfunctionwithoutanyspecificproblems.(Table2)

1. Case 1

A31-year-oldmalepatientwithahistoryofrightunilateral

cleftlipandpalatepresentedtoourclinicwithamissingright

maxillary lateral incisorandalveolarbone loss.Together

withorthodontictherapy,atreatmentplanwasdevelopedthat

includedasymphysisbonegraft,oronasalfistulaclosuresur-

gery,andimplantplacement.Thefirstimplantsurgerywas

performedaftera6-monthhealingperiodfollowingthebone

graft.Tosecureanadequateview,afullthicknessflapwas

created.Theboneheightwassufficientforimplantplacement

andthebuccolingualwidthwasapproximately3mm.Us-

ingSplitMasterexpandingscrews,a4-mmridgeexpansion

wasperformed;subsequently,animplantthatwas3.5mmin

diameterand11mminlengthwasplaced.Topreventbuccal

bonefracture,expandingscrewswerecarefullyhandledwith

patienthadosteoporosis,andtherestweregenerallyhealthy.

Thepostsurgicalfollow-upobservationperiodrangedfrom

24to63monthswithanaverageof44.7months.

Thesurgerywasperformedunderlocalanesthesia.Amid-

crestalincisionwasmadeinthemaxillaryandmandibular

alveolarbone,andthebonewasexposedthroughthecreation

ofafullthicknessflap.Initialdrillingswereperformedinthe

areaofimplantplacement,andtheimplantwasplacedatthe

properplacementdepthusingaSplitMasterNo.1expanding

screw.Gradually, thickerscrewswereusedrelativetothe

finalwidthandlengthoftheimplants.Simultaneousimplants

wereplacedwithself-tappingandsequentialimplantswere

placedwithanapproximately3-to4-monthhealingperiodin

between.Intwocases,agroovewascreatedinthealveolar

ridgewithFriossaws(DentsplyImplants,Mannheim,Germa-

ny)or#15blades,andalveolarridgesplittingwasperformed

usinganosteotome.Then,theimplantplacementsitewasex-

pandedtothewidthoftheimplantbyusingexpandingscrews.

Insomecases,additionalbonegraftwasperformedtoprevent

resorptionofthethinbuccalcorticalplate.Thespacebetween

theimplantsandthebonewasfilledwithgraftmaterialsand,

ifneeded,blockingmembranes.Inoneoftheridgeexpan-

Table 1. Location of implant

Location Number

MaxillaryanteriorMaxillarybicuspidMaxillarymolarMandibularmolarTotal

531211

Young-Kyun Kim et al: Horizontal ridge expansion and implant placement using screws: a report of two cases. J Korean Assoc Oral Maxillofac Surg 2014

Table 2. Overview of cases

PatientsNo.

Age(yr)/sex

SiteAccompanied

surgeryImplant

diameter(mm)Implant

length(mm)Ridgesplitting

methodProsthesis

typeComplications

12

3

4

5

6

31/male60/female

69/female

61/female

65/female

45/female

#12#13#23#35#37#14

#16#11

#12#24

#25

GBRGBRGBRGBRGBRGBR

GBRGBR

GBRSinuselevation,GBRSinuselevation,GBR

3.53.44.3454

53.5

3.54.3

4.3

11121211.511.513

1313

11.58.5

8.5

BoneexpanderBoneexpanderBoneexpanderBoneexpanderBoneexpanderFriossaw,blade,chisel,boneexpander

Friossaw,blade,chisel,boneexpanderBoneexpander

Boneexpander

SinglePFPPFPPFPPFPPFP

PFPPFP

PFPPFP

PFP

NoneSwelling,ecchymosisNoneNoneNoneNone

NoneOsseointegrationfailureNoneNone

None

(GBR:guidedbonyregeneration,PFP:partialfixedprosthesis)Young-Kyun Kim et al: Horizontal ridge expansion and implant placement using screws: a report of two cases. J Korean Assoc Oral Maxillofac Surg 2014

Horizontal ridge expansion and implant placement using screws

235

restorationarea.Boneheightwassufficient for implant

placement;thebuccolingualwidthwasasnarrowas3to4

mm,bonequalitywasD3,andosteoporosiswassuspected.

ahandratchet.Onthebuccalside,a2-mmimplantthread

wasexposed,soGBRwithxenogeneicbones(Biocera;Os-

scotec,Cheonan,Korea)andbarriermembranes(Bioarm;

ACESurgicalSupply,Brockton,MA,USA)wasperformed

intheexposedarea.Aftera4-monthhealingperiod,thesec-

ondsurgerytomaintainthebuccalvolumewasperformed

throughcreatingalabialpouchandgraftingtheBiocera.After

3monthsoforthodontictreatmentforregainingthespaceof

implantprosthesis,aprovisionalrestorationwasplaced.After

theorthodontictreatmentwasfinished(ninemonthsafterthe

implantsurgery),theimplantwasrestoredwithanall-ceramic

crownsupportedbyzirconiaabutmentpost.(Figs.1-6)

2. Case 2

A69-year-oldfemalepatientwithoutanyhistoryofsys-

temicdiseasespresentedtoourclinicwithachiefcomplaint

ofmissingseveralteeth.Underlocalanesthesia,afullthick-

nessflapliftwasperformedintheleftmandibularimplant

Fig. 2. Expansion of buccal plate achieved by splitting the ridge with bone expander in SplitMaster (Mr. Curette).Young-Kyun Kim et al: Horizontal ridge expansion and implant placement using screws: a report of two cases. J Korean Assoc Oral Maxillofac Surg 2014

A B

Fig. 1. Clinical view before implant placement. A. Preoperative intraoral photograph. B. Mucoperiosteal flap was elevated. Narrow alveolar ridge is observed.Young-Kyun Kim et al: Horizontal ridge expansion and implant placement using screws: a report of two cases. J Korean Assoc Oral Maxillofac Surg 2014

A B

Fig. 3. A. Implant was placed at the ex-panded ridge. B. Periapical radiograph after implant placement.Young-Kyun Kim et al: Horizontal ridge expansion and implant placement using screws: a report of two cases. J Korean Assoc Oral Maxillofac Surg 2014

J Korean Assoc Oral Maxillofac Surg 2014;40:233-239

236

Afterinitialdrilling,expansionwasperformedusingSplit-

Masterexpandingscrewsattheleftmandibular2ndpremolar

and2ndmolararea;theareaswereexpandedto3.8mmand

4.3mm,respectively.TwoGSIIimplants(Osstem,Busan,

Korea)whichwere4mmindiameter,11.5mmin length

and5mmindiameter,11.5mminlengthwereplaced.As

measuredbytheOsstellMentor(IntegrationDiagnostics,

Savedalen,Sweden),theprimarystabilityoftheimplantsin

theleftmandibular2ndpremolarand2ndmolarwas76and

77implantstabilityquotient(ISQ),respectively.Thesewere

relativelygoodvalues.Subsequently,axenogeneicbonegraft

(Biocera)wasperformedinthespacebetweenthebonesand

thethinareaofthebuccalside.Thesurgerywasperformed

usingtheone-stagemethod,andafterahealingperiodof

approximately2months,theimplantswererestoredwitha

fixedpartialprosthesis.(Figs.7-11)

Fig. 4. Clinical view of 2nd surgery.Young-Kyun Kim et al: Horizontal ridge expansion and implant placement using screws: a report of two cases. J Korean Assoc Oral Maxillofac Surg 2014

Fig. 5. Delivery of the final implant-supported all-ceramic restora-tion. Young-Kyun Kim et al: Horizontal ridge expansion and implant placement using screws: a report of two cases. J Korean Assoc Oral Maxillofac Surg 2014

Fig. 6. Periapical view 24 months after the placement of implant.Young-Kyun Kim et al: Horizontal ridge expansion and implant placement using screws: a report of two cases. J Korean Assoc Oral Maxillofac Surg 2014

Fig. 7. Clinical aspect before implant placement.Young-Kyun Kim et al: Horizontal ridge expansion and implant placement using screws: a report of two cases. J Korean Assoc Oral Maxillofac Surg 2014

Fig. 8. Expansion of buccal plate achieved by splitting the ridge using the bone expander in SplitMaster (Mr. Curette).Young-Kyun Kim et al: Horizontal ridge expansion and implant placement using screws: a report of two cases. J Korean Assoc Oral Maxillofac Surg 2014

Horizontal ridge expansion and implant placement using screws

237

stillcontroversialastowhetherabonegraftisrequiredfor

thespacegeneratedaftersplitting.Insimultaneousimplant

placements,itiscontroversialwhetherbonegraftmaterials

improveosseointegration6.Ithasbeenreportedthatincases

withbonygapssmaller than3mm,bonegraftmaterials

otherthancollagenspongesarenotrequired7.Also,implants

placedinthespacebetweenexpandedbonesareprotected

frombiodynamicexternalloading.Furthermore,bonycom-

pactioneffectscanoccurasaresultofthecompressionof

bonytrabeculae.Nonetheless,thissurgeryisamethodthat

usesboneelasticity,soitcanonlybeperformedincaseswith

cancellousbonewithinthecorticalboneonbothsides.There-

foretheindicationsofthisproceduremightbelimitedwhen

comparedwithGBRoronlaygraftthatcouldbeappliedin

acancellousbone-deficientarea.Incaseswherethewidthof

thebasalboneistoonarrow,theprimarystabilityortheslope

III. Discussion

Since1990,itwaswidelyusedandreferredtointhelit-

eraturewithvarioustermssuchasridgewidening,thesplit

crestprocedure,andstagedridgesplitting5.Generally,this

surgeryinducesagreenstickfractureinthenarrowalveolar

ridgewithanosteotome.Theprocedureformsanimplantbed

andfacilitatestheplacementofimplantswithwidediameter.

Inaddition,boneregenerationisachievedonbothsides,so

thebonehealingcapacityisgood;therefore,sufficientos-

seointegrationcanbeachievedwithrelativelysmallvolumes

ofbone.Furthermore,a3-monthwaitingperiodisrequired

atminimumfordistractionosteogenesisand6months is

requiredforGBRinimplantplacement.Ontheotherhand,

afterperformingridgesplitting,thefirstplacementsurgery

canbeperformedonthesamedayorwithinthemonth.Itis

Fig. 11. Periapical radiograph 63 months after implant placement.Young-Kyun Kim et al: Horizontal ridge expansion and implant placement using screws: a report of two cases. J Korean Assoc Oral Maxillofac Surg 2014

Fig. 10. Intraoral view after delivery of final implant-supported por-celain fused to metal restoration.Young-Kyun Kim et al: Horizontal ridge expansion and implant placement using screws: a report of two cases. J Korean Assoc Oral Maxillofac Surg 2014

A B

Fig. 9. A. Implants were placed at the expanded ridge. B. Periapical radiograph after implant placement.Young-Kyun Kim et al: Horizontal ridge expansion and implant placement using screws: a report of two cases. J Korean Assoc Oral Maxillofac Surg 2014

J Korean Assoc Oral Maxillofac Surg 2014;40:233-239

238

partialthicknessflapsshowgoodresults.Inthisstudy,and

incasesinvolvingthemaxillaryanteriorareawhereesthetics

arerequired,full-thicknessflapelevationswereperformedin

thealveolarridgeandslightlybelowit.Afterwards,apartial

flapwaselevated.Intheposteriorareas,afull-thicknessflap

waselevatedinmostcases.

The ridgeexpansion techniquementioned in thiscase

report isslightlydifferentfromtheexistingridgesplitting

technique.Theridgesplittingtechniqueisamethodology

toincreasetheridgewidthbyperformingtheridgesplitting

usingachiselaftertheformationofagrooveatthecenter

ofridgecrestusingasaworsurgicalburandismainlyused

inthemaxilla.Iftheridgesplittingtechniqueisperformed

inthemandiblecomposedofmainlycorticalbone,thenit

runstheriskofcorticalbonefractures.Whereas,theridge

expansiontechniqueisastepwisetechniqueusingscrewsof

graduallyincreasingwidth,soithasalowerriskofcortical

bonefracturethantheridgesplittingtechnique.Therefore,

ridgeexpansiontechniqueisconsideredtobeanacceptable

methodtouseonthemandible.

Inthisstudy,onecaseinvolvingimplantplacementinthe

maxillaryanteriorareadevelopedacomplicationoffailed

osseointegration.However, implantreplacementwasper-

formedimmediatelyafterremoval,andsuccessfulprosthesis

treatmentswerecompleted.Buccalcorticalbonefracturedid

notoccurinanyofthecases.Evenaftertheprosthesiswere

functioning,alladjacentalveolarbonesandsofttissuesre-

mainedstable.

Conflict of Interest

Nopotentialconflictofinterestrelevanttothisarticlewas

reported.

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