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Custom Impression Coping for anExact Registration of the HealedTissue in the Esthetic ImplantRestoration

Kenneth F Hinds. DDS'

if is welt icnawn fhat guided soft fissue heaiing with a provisional restoration isessenfiai fo obfain optimai anterior esthetics in the implant prosfhesis. Whatis nof weil known is how to transfer a record of beautifui anatomicaliyheaied fissue fo the laboratory With the advent ot emergence profiie heai-ing abutments and corresponding impression copings, there has been adramatic improvement over the originai 4.0-mm diameter design. This is agreat improvement hawever if sfiil daes not accurately transfer a record afonatamicatly heaied tissue, which is often triangularly shaped, to fhe iabo-ratory. because the impression coping is a round cylinder. This artioieexpiains how to fabricate a "custom impression coping" fhaf is an exactrecord of anatomicaliy heated fissue for accurate dupilcation. This tech-nique is significanf becouse it aiiows an even oioser replicatian of fhenaturai dentitian. (Int J Periadonf Rest Denf 1997; 17:585-591.)

'Private Practice, Laguno Niguel. California.

Reprinf requests: Dr Kenneth F. Hinds, 25500 lîanoho Niguel Road,Suite 2Ó0, Laguna Niguel, California 92056.

impiant denfisfry has evolvedfrom Brânemark's eorly workwith the totolly edentulous archto portiolly edentulous estheticrestorations.' The old standordof jusf aohieying osseointegra-tion, function, ond longevity ofthe implonf restoration is nolonger stote-of-the-art. The newstondard of care requires thatthe implant prosthesis olso beesfhetic.̂ -^

This new esthetic standardin impionf dentistry piaces anincreased ohailenge on thedentai team and the compo-nies manufocturing the compo-nents used. Patients are moreestheticoily demonding todayond require restorations thatreplicate the natural dentition.The only way to satisfy thedemonds of the patient is byproper planning before thestort of freatmenf.^" Eachphose (presurgery and at stage1 ond stoge 2 surgery) is onopportunity tor tissue monipula-tion in the process of achievingperfeofion in the finai esfhefiorestoration. The denfai impiont

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team must tai<e advantage ofeach step fo further refine fhehealing tissue to proper ana-tomic shape, contours, andheaith. The handiing ot the tis-sue at stage 2 surgery is proba-biy the mosf critical phase inthe prooess of resforation.

"Custom-guided" fissueheaiing^ with a provisionairestoration is the mosf pre-dictable way to aohieve nat-ural, anatomically shaped tis-sue and optimai esthetics,iVlany clinicians today preferthat an implant registration orindex be taken at stage 1 sur-gery.^-^ This allows the impiantteam to immediately place anonatomically contoured provi-sional restoration at stage 2surgery and to start fo guidethe soft tissue to heai in anideai, natural morphology thatreplicates the tooth form.^

Affer compiefe heaiing hasbeen obfained (usuaiiy at ó to8 weeks) the besf way to 1rans-fer a record of beautifuliyheaied tissue to the laboratoryfor exact dupiication in fhefinai restoration must be deter-mined.

in the past only 4-mm-diam-eter round impression copingswere avaiiabie fo transfer trian-gular-shaped tissue (in theanterior of the mouth) that was5 to 7 mm. The iaborafory wasthen forced to guess how toexpand the 4-mm opening to afull-size anatomically shapedrestoration. The result was oftenunsatisfactory, and offen a

ridge iap prosthesis, which is nofan ooceptabie esthetic resfora-tion and is incompatible withperiodontai heaith,^''-'^

With the advent of theEmergence Profiie System(Implant Innovations) heaiingabutments/caps 5.0, 6.0, and7,5 mm in diameter and corre-sponding impression copingsfhere has been a dramafioimprovement over the original4.0-mm-diameter design. Thissystem works weil in expandingfhe tissue during stage 2 heal-ing to the proper dimensionand in transferring that size tothe laboratory with the corre-sponding impression cop-¡ng,5,9,n,i2 However, the systemstill does not accurately transferfhe anatomically healed tissue,because the impression copingis a round cylinder and fhe tis-sue is often triangular-shaped(in the anterior of the mouth) oroval-shaped (in the posterior offhe mouth). This system is thebest available to date andwori<s weii in ali situations,except in the esthetic restora-tion when a provisionai hasbeen used to custom guide thefissue healing.

Jansen's technique of mai<-ing two provisional restorationsand using one of them as apici<-up impression coping wiiifransfer the healing fissue veryaccurately.^ The oniy disadvan-tage with this technique is thatthe ciinician must fabricate twoprovisional restorations andmake them exactly identicai.

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The solution to obtaining anexact impression of the heaiedtissue and having the abiiity totransfer this to the laborotory isto customize the pick-up-typeimpression ooping. The presentreport details a new procedurethat provides a ropid methodfor this tronsfer process thatyields optimal esthetic results.

Method and malerials

Two patients requiring estheticrestorations were seiected todemonstrate this new tech-nique. Both patients presentedwith standard externol hexago-nal impiants that had healedfor 8 weeks after stage 2 expo-sure and that were ready forfinal impressions. Guided sofftissue heoling wifh a provisionalrestoration was used to shopethe tissue to ideal anatomicform and health.

Ciinical technique

An anterior toofh and a poste-rior foofh were chosen fo dem-onstrate the effecfiveness ofthis mefhod. The anterior toofhhad a trianguior-shaped rootform, whereas the posteriortooth hod on ovai-shaped roottorm. Previous impression tech-niques ore adequate tor poste-rior teeth with minimal tissuedepth (1 to 2 mm). However, for

anferior teeth in which fhe tis-sue depth is greater than 2mm, the resuits moy not be asaccurote and ultimateiy not asesthefio. This new fechniquemay be used in aii situofions (oilimplants) in the mouth in whichthere are 2 or more millimefersof tissue depth and in whioh anoccurate transter record of thehealed anatomic tissue isdesired.

Fabrication of acustom impression coping

The patient's provisional restor-ation was removed from theimpiant, and the loboratoryanaiog was ottached (Figs laand lb). Regisil bite registrationpaste (Dentsply) was then mixedand used to fill a plastic circuiorcontainer 23 mm deep. The pro-visional restorotion, with its ono-log attached, wos placed intothe Regisii untii it hit bottom (Figs2a and 2b). One of the advan-foges of Regisil is fhaf if setsquickiy. in 1 to 2 minufes. Theprovisional resforation was un-screwed trom the Regisil moidand reposifioned in the patienf'smouth. This prevented tissue ool-iapse over the the implant andalteration ot its shape. As a resultof this manipuiation, an exactregistration of the tissue portionof the provisionai restoration,with the onalog in the mold, wosobtained (Fig 3a).

A 4- or 5-mm pick-up-typeimpression coping was at-tached to the Regisii moid andcoupled fc engage the hexa-gon of the implant analog (Fig3b). Poroelite Dual Cure com-posite resin (Kerr) was mixedand injeoted around the cop-ing (Figs 4a and 4b). Affer 3 to 4minutes the composite resin wosfuliy cured ond the copingcouid be removed, if necessary,the set can be acceleratedwith a standard curing iight. Thisnewly created "custom impres-sion coping" was ciosely exam-ined ond poiished to produce osmooth surfooe.

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Fig la(ieft) Removal at the ideaiiycontoured provisional restoration.

Fig f£> (right) Aftachment of animpiant onaiog to the provisionalrestoration.

Fig 2a (ieft) Plastic cylinder is fiited 23mm deep with Regisii.

Fig 2b (right) Piacement of the provi-sionai restoration with the anaiogqftqched into the container of Regisii.

Fig 3a (ieft) Replication of the tissueportion of the provisionqi restorqfion inthe Regisii maid

Fig 3b (right) Attachment of 5-mm-diameter pick-up-type impressioncoping.

Fig áa (ieft) Injection of the ParceiiteDual Cure camposite resin into theRegisii maid.

Fig 4b (right) Top view of fhe curedcustom impression coping within themoid.

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Fig Sa (ieff) Oustom impression coping.

Fig Sb (right) Comparison of the newcustom impression coping with a ston-dord impression coping qnd the tissueportion of the provisionai restoration.

Fig 6a (left) Oiinicai ottachment ofthe custom impression coping.

Fig 6b (righf) Ciinicai incisai view offhe custom impression coping.

Fig 7a (ieft) Oustom impression cop-ing retained in the impression materiaiwith an implant analog ottoched

Fig 7b (right) finai anatomic tissuecast showing the accurate transferrecord of the heated tissue.

Results

Figures 5a and 5b show anexact repiica of fhe tissue por-fion of fhe provisional resfora-fion. All of these procedureswere performed in 5 fo 6 min-utes while fhe patienf was inthe chair.

Final impression

The potient's provisionai restora-tion, which had prevented col-iapse of fhe tissue, was removed

from the impianf and repiacedwith the custom impression cop-ing (Figs óa and 6b), The customimpression coping was screweddown to its proper position, anda periapicai radiograph wastaken fo verify fit, A standardpick-up impression was fai<enwifh a firm maferiai (such aspoiyether or polyvinyl) and amodified piasfic fray with anaccess hole at fhe sife of theimpression coping. The cusfomimpression coping wos un-screwed fhrough fhe accesshole and fhe impression was

removed. As a resuit, the cusfomimpression coping in Fig 7a wasincluded in fhe impression. Animpianf anaiog was fhen at-tached, and gingivai simulafionmaterial wos injected aroundthe portion of the cusfom im-pression coping fhat projeofedouf of the impression.

The impression was pouredin die stone fo mai<e the finaitissue cast for the iaborotory Asa resuif, fhe iaboratory had anexact replica of the pafienfshealed anafomicaily shapedfissue (Fig 7b). The impiant

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Fig Sa Multiple-layered image showing the custom abuf-ment transitioning through the tissue.

Fig 8b final restoration' The impiant is piaced in on ideaiposition.

figs 9a and 9b Olinicai views showing the custom Impression Fig 9c Final restoration: The impiont is placed in a nonidealcoping. pasitian.

restoration could then be fabri-cated accurately to fit fhehealed tissue and obfain animproved esthetic result.

Figures 8a ahd 8b show theresuifs of fhis new technique inan ideal situation, in whioh theimpiont wos pioced properly ina normoi shoped ridge. This 45-year-old male presented with afractured roof and mesiai de-tect to the opex of his moxiilary

righf ioferoi incisor. After ex-traotion, guided tissue regener-ation with a membrone, andproper healing, the impiantwas piaoed and restored witha custom abutment and acementoble porcelain pros-thesis. The anatomio customabutment in Fig 8a replicatesthe naturai root form in thisesthetic restorotion.

Figure 9c shows the resuitsof this new technique in a situa-tion in which the impiant wasplaced in a nonideal position.This 21-year-old male presentedwith a ioose Maryiand fixedportial denfure fo restore acongenitaily missing maxillaryright firsf premoior. The implantwos placed too far to the buc-cal and too ciose fo fhe adja-cent tooth. As o result, it angled

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distaily toward the maxillaryright second premolar, andmade standard pick-up-typeimpression techniques difficult.The finai impression was takenwith a custom impression cop-ing as illustrated in Figs 9a and9b. The impiant was restored bymaking a 15-degree angle cor-rection with a custom abut-ment and a cemenfable por-celain prosfhesis.

Discussion

This articie has demonstratedfhe effectiveness of o newmethod for transferring heaiedciinicai tissue fo the laboratoryvia a custom impression cop-ing. This is a significanf finding,because it not only is a veryoccurate transfer mefhod, butit has aiso been shown to workin situations with ideal impiantplaoement and fhose withsevere angle problems, it isanticipated fhat this methodwill have universal applicotionin implant dentistry.

Another advantage of thisnew technique is fhat it onlyrequires approximately 5 fo óminutes to aofuaiiy fabricatethis custom impression coping.Thus, in just a few minutes anaccurafe coping can be madethaf wifi ulfimateiy save the clin-ician chair time when the per-manent restoration is delivered.Since the laboratory will have avery accurate modei of theheaied anatomic fissue, the

permanent restoration will fitmore precisely, require lesschair-side modification, andhave a much improved, consis-tent esthetic result.

Conciusion

With the new esthetic standordin implant dentistry, it is impor-tant that new techniques andmethods be developed tomeet increasing demands. Thisarticie hos introduced a newteohnique to aid the oiiniciantoward meeting this new chal-lenge. The fabrication of a cus-tom impression coping hasbeen shown fo be an accuroteand efficient mefhod to frans-fer a record of the healedanatomic tissue to the labora-tory. This wiii aliow the iobora-tory technician to fabricate arestoration that fifs preciseiywifh proper contour, function,and esthetios.

Acknowledgments

Ttie outhor would iike to ttiani< DrChories Ribok for his enoouragementond criticol reoding of this monuscript.

Reterences

t. iHobo S, ichido E, Goroio LT. Osseointe-gration ond Ooolusoi Rehobiiitotion.Chicago'Quintessence, 1W1:7-11.

2. Touoti B. Custom-guided tissue heal-ing for imoroved aestt iefics inimpiant-supported restorotions. Int JDent Symp 1995:3:36-39.

3. fiifi<in IÎG Deveioping o proper se-quence for implant-supported resto-rotions. Inf J Dent Symp l'?95:3:'10-43.

A. Sheppoid WK, Ducor JP London RMPlanning far impiont piocement.Calif Dent Assoo J 1995:23(3):14-t8,

5. Jonsen CE. Guided soff tissue heal-ing in implont dentistry. Colif DentAssoc J 1995:23C3):57-ód.

6, Hochwald DA. Surgicai tempioteimpressian during stage 1 surgeryfor fobr icat ion of a provisionolrestoration to be pioced at stoge 2surgery J Prosthet Dent 1991,ö6(6): 796-798

7 Reiser G, Dombush Jlî, Cohen R, Ini-tiating restorative procedures at firststage surgery with a posit ionalinde«: A case study, int J PeriodontRest Dent 1992.12:279-293.

8. Prestipinc V Ingber A. Implant fixfureposition registration at the time offixture p iocement surgery. PractPeriadontics Aesthet Dent !992:4C9):23-27.

9, Lozzora RJ, Manoging the soft tissuemargin: The key to impionf aesthet-ics, Proct Periadantics Aesthet Dent1993:5CS).l-7.

10. Lazzaro RJ. Criteria for implontseiectian: Surgicoi and prosthetioconsiderations. Proot PeriadonticsAesthef Dent 1994:óC9):55-ó2.

11. Saadoun AP Singie tooth implantrestoroticn: Surgicai manogementfor aesthetic resuits. Int J Dent Symp1995:3(1 ).30-35.

12. Saadoun Afi Sullivan DY Krisohek M,Gaii MC. Singie tooth implant mon-agement for success. Pract Perio-dontics Aesthet Dent 1994:6(3):73-80,

Volume 17, Number 6,1997