Journal of Dental Sciences (2011) 6, 53e60

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Case Report

Immediate implant placement and provisionalizationwith simultaneous guided bone regeneration in theesthetic zone

Chih-Long Chen 1, Chih-Ling Chang 1,2, Shih-Jung Lin 1,3*

1Department of Dentistry, Shin Kong Wu Ho-Su Memorial Hospital, Taipei, Taiwan2Department of Dentistry, National Yang-Ming University, Taipei, Taiwan3College of Medicine, Chang Gung University, Taipei, Taiwan

Received 4 November 2010; accepted 10 January 2011Available online 21 March 2011

KEYWORDSguided boneregeneration;immediate implant;immediateprovisionalization

* Corresponding author. DepartmentHo-Su Memorial Hospital, No. 95-BDistrict, Taipei 111, Taiwan. Tel.: þ88

E-mail address: louissj.lin@msa.hin

1991-7902/$36 Copyrightª 2011, Assocdoi:10.1016/j.jds.2011.01.001

Abstract The procedure for immediate implant placement and provisionalization is time-saving, possibly with only one surgical intervention required, although allowing maximal pres-ervation of peri-implant tissues. In this case, we extracted a fractured maxillary right centralincisor of a 46-year-old woman with high esthetic expectations, and a transmucosal implantwas immediately installed. Simultaneous guided bone regeneration was performed to correctthe defects at the facial side of the socket and augment the alveolar ridge horizontally.Primary stability of the implant body and wound closure without tension were confirmed.Connection of a 15� angled abutment and fabrication of a provisional acrylic resin crownwithout occlusal contact were also completed in the same appointment. After intensivefollow-up and soft-tissue molding for 6 months, the customized zirconia abutment and all-ceramic crown were definitively fabricated. During the 18-month follow-up period, the patientwas satisfied with the esthetic and functional results.Copyright ª 2011, Association for Dental Sciences of the Republic of China. Published byElsevier Taiwan LLC. All rights reserved.

of Dentistry, Shin Kong Wu1, Wenchang Road, Shilin6 2 28332211x2170.et.net (S.-J. Lin).

iation for Dental Sciences of the Re

Introduction

Restoration of missing teeth in the esthetic zone is a greatchallenge for dental practitioners. Implant-supported fixedprostheses are usually attempted before other optionssuch as conventional bridges or removable dentures toavoid damage to adjacent teeth and provide better chew-ing function.

public of China. Published by Elsevier Taiwan LLC. All rights reserved.

54 C.-L. Chen et al

The number of osseointegrated implants used in par-tially edentulous patients has drastically grown since the1980s. An implant-supported crown to replace a singletooth gap is the most frequent indication today for implanttherapy.1 Although the main objective of restoring poste-rior sites is to reestablish masticator function, there is lessconcern about esthetics. In addition, implant practitionersencounter increasing numbers of implants that need to beplaced in the anterior esthetic zone with high estheticexpectations from patients. Advanced periodontitis,unrestorable caries, fractures, and traumatic injuries arethe most common reasons for missing anterior teeth.Various risk factors which may compromise the predict-ability of the esthetic results should be assessed in detailbefore commencing treatment procedures.2

Nowadays, shortening the overall treatment period andminimizing the number of surgical interventions in implantdentistry are expected by patients and clinicians. Tradi-tional guidelines advise a 2e3-month period of socketremodeling after tooth extraction and an additional 3e6months of load-free healing that were essential forosseointegration in the 1980s.3 Alternative protocols suchas immediate implant placement at the time of extraction4

and a method of early implant insertion after a few weeksof soft-tissue healing5 have been used for about 20 years.The advantages of only one surgical procedure and reducingthe overall treatment time have encouraged clinicians toimmediately install implant fixtures into extractionsockets.6 Simultaneous guided bone regeneration (GBR)procedures, using bone grafts and barrier membranes, areusually necessary in such a situation to correct peri-implantdefects and/or to augment surrounding tissues. Thisapproach can also achieve successful treatment outcomeswith high predictability and a low risk of complications,both from functional and esthetic points of view.5

Fixed and removable interim restorations placed inanterior implant sites during the healing phase provideesthetic relief and protect tissues. The appearance ofmetal or resin connectors in fixed partial dentures and theinconvenience of removable dentures can bother patientswith high esthetic and psychological demands. The place-ment of a temporary restoration connected to the fixtureon the day of implant surgery may partially resolve thisproblem. The shape of the peri-implant soft tissue is alsoachieved more quickly using provisional crowns than withhealing caps.7 Several clinicians have designed immediateprovisional crowns without functional contact to reduce thepossibility of early implant failure.8,9 With careful caseselection, this treatment protocol can serve as a predict-able procedure with high survival rates.

The purpose of this article is to present a case ofimmediate implant placement combined with simultaneousGBR to correct a severe buccal dehiscent defect followedby immediate provisionalization. The short-term resultsmet the patient’s esthetic, functional, and psychologicaldemands in a reduced treatment period.

Case report

A 46-year-old female non-smoking patient complained ofmild discomfort and gingival problems at tooth 11 before

finishing a full-veneer crown restoration. She was in goodgeneral health, and her medical history was unremarkable.Her previous dental history showed that she had highesthetic expectations. It was noted that the patient hada low smile line (Fig. 1A) and a thin, scalloped gingivalbiotype (Fig. 1B). A clinical inspection of the oral cavityrevealed a gingival swelling on the facial side of tooth 11,which had been restored with a provisional resin crown.This symptomatic tooth had been treated with forced-eruption and crown-lengthening procedures to correcta subgingival caries and expose an adequate sound toothstructure for a ferrule effect 5 years previous. A castpostecore and single crown were also fabricated at thattime. She was under prosthodontic retreatment because ofthe previous crown having become dislodged. Slightpalpation and percussive discomfort with an isolated deepclinical probing depth of 8 mm of the midfacial gingivawere found on examination. One of the neighboring teeth,the left central incisor, had been restored with an all-ceramic crown but was free of caries and periodontalproblems. However, there was a discrepancy between thecrown height of both central incisors, because tooth 11 wasshorter by about 0.5 mm at the gingival level than thecontralateral tooth. The periapical radiograph demon-strated a filled root canal cemented with a large metalpostecore (Fig. 1C). Radiopaque material protruding fromthe root apex and no apical radiolucency were alsoshown. Vertical bone levels of adjacent roots were wellmaintained.

The clinical diagnosis of tooth 11 was a vertical rootfracture. Immediate implant placement and provisionali-zation were the recommended treatment because of thepatient’s desire for a minimal number of surgical inter-ventions and the maintenance of an esthetic appearanceduring the treatment procedures. The clinical and radio-logical findings in this patient added up to the esthetic risk-profile analysis2 (Table 1), and the results showed that thiscase was to be considered medium- to high-risk because ofseveral unfavorable conditions. The patient was informedabout all relevant aspects of the proposed treatment, andshe agreed to it.

The first step was the careful extraction of tooth 11under local anesthesia using a 2% lidocaine solution witha vasoconstrictor. The metal postecore was dislodged atthe beginning of this procedure, and then a full-thicknessflap extended to the adjacent teeth using a sulcular incisionwas raised to extract the residual root (Fig. 2A). Buccalbony dehiscence and a vertical fracture line of the rootwere clearly observed. Root fragments were carefullyremoved with a periotome and appropriate forceps(Fig. 2B). The extraction socket was thoroughly debridedwith caution to prevent infection and a thin buccal plate(of <1 mm thick) with dehiscence, 3 mm wide, and 5 mmdeep was identified (Fig. 2C).

Implant bed preparation was completed after standardprotocols using incremental sharp spiral drills and copiouschilled saline. An ideal three-dimensional implant positionwas obtained mesiodistally, orofacially, and coronoapi-cally3 (Fig. 2D). In the buccopalatal position, the drillingpoint was 3 mm above the root apex palatally, and it wasprepared with a round bur. The drill was extended 3e4 mmapically to obtain primary stability. In the coronoapical

Figure 1 Extraoral and intraoral views of an 46-year-old woman before treatment. (A) Low smile line of the patient. (B) Theclearly visible gingival swelling facially of tooth 11. (C) Large metal postecore cemented into the root canal of tooth 11 on per-iapical radiography.

Immediate implant and provisionalization 55

position, the implant platform was planned to be locatedapproximately 2e3 mm apical to the midfacial mucosalmargin of the future implant crown. A 12-mm taperedeffect with a rough surface (sand-blasted, large grit, andacid-etched, SLA) ITI Taper-Effect implant (InstituteStraumann, Waldenburg, Switzerland) was put in place(Fig. 3A). The fixture achieved excellent primary stability.A combined bony defect at the buccal site includinga dehiscence-type defect and a 1-mm horizontal gapbetween the residual buccal plate and implant body wasfound. The exposed surface was still within the alveolarhousing of the premaxilla. A localized GBR procedure was

Table 1 The current patient’s individual esthetic risk profile.

Esthetic risk factors Low

Medical status Healthy patient and intact

immune system

Smoking habit Non-smoker

Patient’s esthetic expectations LowLip line Low

Gingival biotype Low scalloped, thick

Shape of tooth crowns RectangularInfection at implant site NoneBone level of adjacent teeth �5 mm to contact point

Restorative status ofneighboring teeth

Virgin

Width of edentulous span One tooth (‡7 mm)

Soft-tissue anatomy Intact soft tissue

Bone anatomy atalveolar crest

Alveolar crest withoutbone deficiency

then undertaken using bone grafts and a collagen mem-brane. Bone substitute (Sinbone HT, Purzer Pharmaceu-tical, Taipei, Taiwan) was applied directly to the denudedimplant surface, and the marginal gap between the buccalplate and implant surface was filled (Fig. 3B). Placement ofbone substitutes was also gradually extended to theperiphery, and an “overbuilding” convexity at the site oftooth 11 was achieved. A bioabsorbable collagen membrane(Periaid, Collagen Matrix, Franklin Lakes, NJ, USA) cove-red the bone fillers (Fig. 3C), and soft-tissue closure ina non-submerged approach was secured with 5-0 sutures(Fig. 3D).

Medium High

Reduced immune system

Light smoker(<10 cigarettes/day)

Heavy smoker(>10 cigarettes/day)

Medium High

Medium HighMedium scalloped,medium thick

High scalloped, thin

Slightly triangular Triangular

Chronic Acute5.5e6.5 mm to

contact point

�7 mm to contact point

Restored

One tooth (<7 mm) Two or more teethSoft-tissue defects

Horizontal bone deficiency Vertical bone deficiency

Figure 2 Surgical procedures of immediate implantation. (A) Full-thickness flap and a visible vertical fracture line of the root andbuccal dehiscent bony defect. (B) Complete tooth extraction. (C) Imperfect thin buccal plate with dehiscence and circumferentialdefects. (D) Ideal three-dimensional implant position.

56 C.-L. Chen et al

A 15� angled temporary abutment was simultaneouslyinserted and tightened to 15 N cm, and the screw-accesschannel was closed with a temporary restoration (Caviton,GC Corp., Tokyo, Japan) (Fig. 4A). A postoperative peri-apical radiograph confirmed the appropriate implant posi-tion and gap-free seating of the temporary abutment(Fig. 4B). A acrylic resin crown fabricated chair-side wascemented into the implant abutment and adjusted with noocclusal contacts (Fig. 4C). The patient received analgesicsand antibiotics for 3 days postsurgically. In addition, shewas instructed to use a 0.1% chlorhexidine digluconate rinsetwice daily and avoid tooth brushing at the surgical site.

Figure 3 Implant installation. (A) An ITI TE implant was screwedguided bone regeneration procedures. (D) Soft-tissue closure in a

No complications were noted during the postsurgicalhealing period. After several appointments for temporarycrown adjustments and the soft-tissue conditioning phase,the implant site had favorably healed by 6 months (Figs. 5Aand 5B). A periapical radiograph also confirmed that theimplant was well-integrated (Fig. 5C). Subsequently, thetemporary abutment was replaced with a screw-retainedmesostructuremade of zirconia (Fig. 6A) and a definitive full-ceramic crown was cemented onto it (Fig. 6B).

The 18-month follow-up examination revealed stable,healthy peri-implant soft tissue (Fig. 7A). Thepatientwas alsosatisfied with the esthetic outcome (Fig. 7B). Radiographic

in. (B, C) Correcting the defects and augmenting the ridge bynon-submerged manner.

Figure 4 Immediate provisionalization. (A) Connection of a 15� angled abutment and closure of the screw channel. (B) Post-operative radiograph. (C) Cementation of a chair-side fabricated temporary crown.

Immediate implant and provisionalization 57

integration between the bone and implantwas also confirmedby periapical radiography (Fig. 7C).

Discussion

Osseointegration is recognized as a stable, predictable, anddesirable biological interface in implant dentistry. Earlypublications on osseointegration suggested principles andtechniques to predictably achieve this result includingminimal trauma, precise ostectomy preparation, steriletechnique, suitable biomaterials, and stress-free healing.3

Figure 5 Six months after implant surgery and the period of softlocal anatomy showing convexity in the alveolar crest. (C) Confirm

Branemark’s protocol required submucosal healing for 3e6months, although Schroeder’s permitted transmucosal heal-ing for 3e4months.10 From failing natural tooth extraction tocomplete reconstruction with an implant-supported pros-thesis, the traditional time-consuming protocol was ack-nowledged to be empirical in nature.11 Apart from successfulosseointegration, implant practitioners and researchersweretrying to minimize treatment times in accord with patients’interests. The procedures of immediate implant placementand provisionalization were recently tested in several caseseries using modern implants.12,13 Cornelini and colleagues13

used the same ITI Taper-Effect implants installed in the

-tissue molding. (A) Facial view of healed surgical site. (B) Theation of a well-integrated implant in this radiograph.

Figure 6 Definitive prosthodontic restoration. (A) Replacing the temporary abutment with a zirconia mesostructure.(B) Cementation of a full-ceramic crown.

58 C.-L. Chen et al

maxilla and mandible. Most of the 22 teeth were premolars,although nine of themwere incisors. NoGBRprocedureswereperformed when bone defects were <2 mm, and theyobtained a satisfying result of a 100% survival rate in a 1-yearobservation period. Other studies also showed high survivalrates ranging 93.5%e100% with follow-up periods of 6e52months, irrespective of the brand of dental implants,although none of these was a randomized controlled study.Therefore, it could be concluded that immediate implantplacement andprovisionalization arepractical protocolswithhigh short-term survival rates in some situations.

The definition of immediate restoration/provisionaliza-tion is a restoration inserted within 48 h of implant place-ment but not in occlusion with the opposing dentition.14

The interval is reserved for laboratory procedures. In thepresent case, we fabricated the provisional restorationdirectly at the chair-side because of probable risks ofimpression taking. The impression material could haveflowed into the submucosal area and have directly con-tacted the flared-shaped implant neck. In other words, thecoronal portion of the fixture might have become stuck to

Figure 7 Eighteen-month follow-up. (A) Stable and healthy tiss(C) Successful osseointegration confirmed in a periapical radiograp

the impression material. The primary stability could havebeen damaged during the removal of the impression tray,and this might have seriously jeopardized the implantsuccess. For the same reason, clinical preparation of pre-formed abutments using handpieces should also be avoidedbecause they can produce vibration damage, althoughthere is no published literature concerning the possible riskand how it affects the primary stability. Careful presurgicalanalysis and precise three-dimensional implant positioningare therefore very important. Any inaccuracies willcomplicate the immediate restorative procedures and evenaffect the final functional and esthetic outcomes. Fortu-nately, the standardized 15� angulated abutment wasselected in this case and connected to the ideally posi-tioned implant with no adjustment, which facilitated thefabrication of a cement-retained temporary restoration.

In addition to saving time, the potential to maximallypreserve hard and soft tissues is another rationale forimmediate implant and provisionalization. The originalmidfacial gingival and interdental papilla can be mechan-ically supported by the provisional restoration and GBR

ue around the implant. (B) Patient smiling with satisfaction.h.

Immediate implant and provisionalization 59

procedures. In a very recent review article,15 the result stillindicated a mean peri-implant bone loss ranging from 0.2 to0.5 mm and an average midfacial gingival recession of0.55e0.75 mm. Kan et al.16 reported a mean loss of papillaheight of 0.39e0.53 mm. The most obvious recognizablesoft-tissue change in this reported case was a reduction inpapilla height between the two central incisors. No clini-cally notable midfacial gingival recession was found. Thisimperfect result may have been the cause of the restor-ative status of the adjacent tooth and the surgical traumato the offending papilla.

Treatment outcomes of immediate implants can beaffected by the presence of a previous infection17 and soft-tissue dehiscence over the extraction site,18 especially whennon-resorbable barrier membranes are used for guided boneregeneration.19,20 In such cases, chronic infection caused byroot fracture carries a medium risk for complications withesthetic significance.2 There is, however, still controversyabout whether implants placed into sockets with a chronicinfection have an increased rate of early failure. Lindeboomand coworkers21 clearly demonstrated a higher failure rate incases with existing periapical lesions, whereas another studydid not indicate a significant difference.22 There is still a lackof definitive evidence regarding the effect of the localpathology on the survival of immediate implants. A more-rational approach seems to be to delay implant installation insites with acute inflammation. The other point of concern,soft-tissue dehiscence at the implant site with GBR, is asso-ciated with reduced volumes of regenerated bone in peri-implant defects.19,20 However, this complication can mostlybe avoided by using collagen membranes23 as shown in thiscase.

Exposure of implant threads because of insufficientalveolar ridge width might lead to high implant failurerates.24 Depending on the size andmorphology of the defect,various augmentation procedures can be used. The criticalrequirement for implant success is to achieve initial implantstability before any augmentation procedures, becauseosseointegration cannot be achieved in mobile implants.25

Among the various graft materials, autografts are regardedas the gold-standard bone graft material for GBR because oftheir osteogenic, osteoinductive, and osteoconductiveproperties. Because of a limited amount of available autog-enous bone in the adjacent area and the avoidance ofa second surgical wound, we alternatively grafted depro-teinized bovine bone material. It was used to support thearea intended for bone augmentation, allow the ingrowth ofbone-forming cells, and support bone-implant contactformation. The “overbuilding” of the vestibular contour ofthe alveolar bone crest was also intended to provide therequired support and long-term stability for the overlyingsoft tissue. To avoid soft-tissue invasion of the graft mate-rials, a collagen membrane with high biocompatibility wasapplied above the grafted bone in the characters of thebarrier. A final important step was to close the wound withtension-free flap adaptation. In recent clinical studies,application of bone substitutes in conjunction with theplacement of barrier membranes successfully covered pre-viously exposed implant surfaces in cases with similardefects.23,26,27 This technique used for the purposes of cor-recting dehiscence defects and augmenting the ridge later-ally seems to be reliable and predictable.

The thin gingival biotype and triangular crown shape ofthe patient represented high-risk characteristics foresthetic implant therapy. In contrast to a thick biotype,thin and friable gingiva has a greater possibility of reces-sion, loss of papilla height, and resorption of the underlyingalveolar volume.28 Findings of Botticelli et al. stronglyindicated that immediate implant placement might notprevent physiologic modeling/remodeling that can occur onthe ridge after tooth removal.29 The change in the verticalbone level was more pronounced at the buccal than thelingual aspect of the ridge because of the early disap-pearance of the bundle bone which occupied a large frac-tion of the marginal portion of the buccal bone wall.Therefore, special procedures should be modified to makegreat efforts to preserve the existing hard and soft tissuesat the implant sites such as using minimally traumaticsurgical and regenerative techniques. Bone preparationshould be relocated palatally to avoid jeopardizing theintegrity of the buccal wall of the socket and perforatingthe facial bone. A void maintained between the implantbody and buccal wall was grafted with bone particles asdescribed above. This method can maximally leave the thinbuccal wall undamaged. Additional grafting of the externalsurface of the buccal bone wall was shown to slightlyincrease or at least maintain the horizontal dimension ofthe alveolar bone. This compensated for the resorption ofthe naturally thin bone wall, and we decided not to performan adjunctive connective tissue graft.

In conclusion, immediate implant installation and provi-sionalization combined with simultaneous guided boneregeneration in postextraction sockets with bony defects areappealing to clinicians. According to the literature, highimplant survival rates and predictable good estheticoutcomes can be achieved with short-term follow-up.Although postextraction bone remodeling will occur irre-spective of the placement of an implant,29,30 the time savedis truly a great advantage for patients and implant practi-tioners. Because of a lack of long-term results, this protocolshould be used with caution, and a number of guidelines andprerequisites need to be seriously considered. More long-term perspectives and controlled clinical studies are neededto guarantee the success of this approach, especially foresthetic outcomes.

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