Implant Placement at the Time ofMaxillary Molar Extraction: TreatmentProtocols and Report of ResultsPaul A. Fugazzotto*

Background: Implant placement at the time of maxillarymolar extraction presents a number of potential benefits to pa-tients. A technique to predictably attain implant placement inideal positions was reported previously.

Methods: A total of 391 rough-surface implants wereplaced in 386 patients at the time of maxillary molar extrac-tion. Concomitant regenerative therapy was performed asnecessary. Implants were followed for up to 75 months witha mean follow-up of 40.3 months.

Results: A total of 389 of 391 implants were functioningsuccessfully for up to 75 months with a cumulative survival rateof 99.5%. Criteria for determining implant morphology anddimension are presented.

Conclusion: Implant placement at the time of maxillary mo-lar extraction with concomitant regenerative therapy as neededand subsequent restoration is a predictable treatment modality.J Periodontol 2008;79:216-223.

KEY WORDS

Bone regeneration; dental implants; maxilla; molar.

Anumber of treatment options otherthan a conventional fixed pros-thesis are available to the clinician

at the time of maxillary molar extraction.The clinician may opt to allow the ex-traction socket area to heal and reenterthe region later to perform the necessaryaugmentation therapy. An implant wouldbe placed during a subsequent surgicalvisit and ultimately be restored with asingle crown. Although such an ap-proach is the least technically demand-ing of the available treatment options, itsubjects the patient to the greatest num-ber of surgical procedures.

Augmentation of an extraction socketat the time of tooth removal has demon-strated a high degree of predictability withregard to regenerating damaged alveolarbone.1-3 However, such an approach re-quires a second surgical session to placean implant.

Ideally, an implant could be placed atthe time of maxillary molar extraction,and concomitant regenerative therapycould be performed if necessary. Fol-lowing maturation of the regeneratinghard tissues and attainment of osseoin-tegration, the implant would be restoredwith a single crown. The theoretical ad-vantages of such an approach are min-imization of the number of surgicaltraumas to the patient and significantcontraction of the overall course of ther-apy. Unfortunately, implant placementin such a situation all too often has beendictated by the residual extraction socket

* Private practice, Milton, MA.

doi: 10.1902/jop.2008.070338

Volume 79 • Number 2

216

morphology resulting in a less than ideal implant po-sition.4

A recent report5 documented the placement of 17maxillary implants at the time of maxillary molar ex-traction and their subsequent restoration with singlecrowns. The 5-year cumulative survival rate was 82%.The one clinical case presented in the article demon-strated that the implants had been placed in the palatalroot sockets at the time of tooth removal. Restorationof an implant in such a non-ideal position presents thepotential for difficulty in patient plaque-control effortsand raises concerns of severely off-angle forces beingapplied to the implant during function and/or para-function. Hsu et al.6 reported that application of suchoff-angle forces significantly increases the magnitudeof force to the bone surrounding the implant.

To help ensure that the final functional and esthetictreatment outcomes of implant placement at the timeofmaxillary molar extractionareat least equal to thoseattained throughaugmentationat the timeofmaxillarymolar extraction and implant placement at a secondsurgical visit, the implantmustbeplaced inan ideal re-storative position. A technique was published to helpeffect such ideal implantplacementat the timeofmax-illary molar extraction.7 The short-term clinical resultsof this treatment approach demonstrated a high de-gree of predictability, with a reported early cumulativesurvival rate of 100% at up to 18 months in functionwith a mean time of 12.4 months in function.

Continued evolution of the aforementioned tech-nique of implant placement at the time of maxillarymolar extraction has led to a decision tree for selectionof implant morphology and dimensions to be used whenperforming such therapy. This article reports on thelonger-term results of this treatment modality and thedecision tree that is now used.

MATERIALS AND METHODS

This study was a retrospective analysis of case re-cords of patients treated as part of routine periodontaland implant treatment. All subjects underwent im-plant placement between 2003 and 2006 in the au-thor’s private practice. A total of 206 females and180 males were treated; subject age ranged from 28to 76 years. Prior to initiation of implant placementand subsequent restoration, thorough medical histo-ries were taken for all patients. Patients were excludedfrom consideration for implant therapy for one or moreof the following reasons: history of chemotherapyand/or head and neck radiation therapy within the24 months prior to consultation; history of intrave-nous bisphosphonate therapy; history of uncontrolleddiabetes; history of any other medical concerns thatwould render the patient a poor candidate for surgeryin general; a smoking habit >10 cigarettes per day;an inability or unwillingness to exhibit appropriate

plaque-control efforts; or an unwillingness to committo an appropriate post-therapeutic maintenance re-gime.

A thorough intraoral examination with appropriateradiographswascarriedout for all patients.Radiographsincluded periapical films, panoramic films, and com-puterized axial tomography scan studies.

Face-bow mountings of maxillary and mandibularmodels were carried out when necessary. Compre-hensive treatment plans were developed between theauthor and all other treating clinicians and laboratorytechnicians prior to the initiation of therapy.

The flap designs used at the time of maxillary mo-lar extraction, simultaneous implant placement, andconcomitant regeneration, if necessary, have been de-scribed in previous publications.8 These flap designsinclude mesio-buccal, disto-buccal, mesio-palatal, anddisto-palatal releasing incisions; horizontal extensionsof the buccal releasing incisions as necessary; and useof a rotated palatal pedicle flap or pedicle flap fromthe tuberosity area when required.

Following sectioning of all maxillary molars to beextracted and removal of each root individually, withcare being taken to preserve the residual interradicu-lar bone, therapy proceeded in one of the followingfour manners.

Sufficient Alveolar Bone Height and WideInterradicular SeptumFollowing its manipulation as described below, a wideinterradicular septum was defined as a septum thatencases the rough surface of the inserted implant. A2.2-mm guide drill was used to prepare the initial os-teotomy in the interradicular bone to its final depth.Tapered osteotomes of increasing diameters, whichcorresponded to the drilling sequence for the implantto be placed, were used to spread the interradicularbone. A 2.2-mm–wide tapered osteotome was insertedfirst and manipulated in thee bucco-lingual and mesio-distal directions to increase the size of the osteotomy.Then, a 2.8-mm–wide tapered osteotome was used inthe same manner as was a subsequent 3.5-mm–wideosteotome. A 4.2-mm tapered osteotome was usednext with no manipulation of the interradicular bonein the bucco-lingual or mesio-distal directions. One oftwo implant designs was used. Ideally, a tapered-endimplant with a 4.8-mm apical diameter and a 6.5-mmdiameter platform was inserted into the manipulatedinterradicular bone. However, if use of the aforemen-tioned implant would have resulted in loss of signifi-cant portions of the interradicular bone because theimplant widened in its most crestal third, a parallel-walled, 4.8-mm diameter implant with a 6.5-mm di-ameter restorative platform was used. Particulate graftmaterial was placed in the residual extraction socketdefect surrounding the implant except when the

J Periodontol • February 2008 Fugazzotto

217

horizontal defect dimension between the outer aspectof the implant and the surrounding alveolar bone didnot exceed 3 mm on any aspect of the implant. A se-cured covering membrane was used as describedpreviously,9 and the mucoperiosteal flaps were su-tured with interrupted expanded polytetrafluoroethyl-ene (ePTFE) and plain gut sutures to ensure passivesoft tissue primary closure (Figs. 1 through 4).

Sufficient Alveolar Bone Height and NarrowInterradicular SeptumA narrow interradicular bony septum was defined as aseptum that would not wholly encase the rough sur-face of the implant body following interradicular bonemanipulation and implant placement. A round burwas used to notch the most crestal aspect of the inter-radicular bone. A 2.2-mm–wide tapered osteotome

was used to the final depth of the planned osteotomy.This osteotome and subsequent osteotomes of 2.8and 3.5 mm in diameter were used in the manner de-scribed previously to manipulate the interradicular bone.The final diameter of the osteotomy was 3.5 mm com-pared to the 4.2-mm–wide osteotomy described above.A tapered-end implant with a 4.0-mm diameter apexand a 6.5-mm diameter restorative platform was in-serted. Appropriate regenerative materials, includingmembranes, were used, and the mucoperiosteal flapswere sutured as described previously (Figs. 5 and 6).

Insufficient Alveolar Bone Height and WideInterradicular SeptumA 2.2-mm–wide trephine was used to prepare an os-teotomy within 1.0 mm of the sinus floor. A flat-endedosteotome was used to implode the interradicular bone

Figure 1.A patient presented with a fractured and hopeless maxillary first molar.

Figure 2.The hopeless molar was extracted, and the residual extraction socketdefect was debrided. Adequate interradicular bone is present forplacement of an implant with a 4.8-mm–wide apex and a6.5-mm–wide platform. No additional bone height is required.

Figure 3.Following osteotome use in the described manner, the implant andappropriate regenerative materials were placed.

Figure 4.A radiograph taken 35 months after restoration demonstrates stabilityof the crestal bone around the implant. Another implant subsequentlywas placed anterior to the implant under study during this time.

Implant Placement at the Time of Maxillary Molar Extraction Volume 79 • Number 2

218

as described in a previous publication.7 The osteotomywas widened sequentially with 2.8-, 3.5-, and 4.2-mm–wide osteotomes. A tapered-end implant with a 4.8-mmdiameter apex and a 6.5-mm diameter restorativeplatform or a parallel-walled implant with a 4.8-mmdiameter and a 6.5-mm diameter restorative platformwas placed as determined by the previously describedcriteria. Once again, regenerative materials, includingmembranes, were used, and the flaps were sutured asdescribed earlier (Figs. 7 through 10).

Insufficient Alveolar Bone Height and NarrowInterradicular SeptumA 2.2-mm–wide tapered-end osteotome was used tothe desired depth to increase alveolar bone height.

This depth never exceeded 1 mm less than the distancefrom the sinus floor to the tip of the residual interradic-ular bone. The osteotomy was widened sequentiallywith 2.8- and 3.5-mm–wide tapered-end osteotomesto the already determined osteotomy depth.A tapered-end implantwitha4.1-mmdiameterapexanda6.5-mmdiameter restorative platform was inserted. Appropri-ate regenerative materials, including membranes andsuturing techniques, were used as discussed previ-ously (Figs. 11 through 13).

Soft tissue primary closure was attained at all sites.Postoperativemedicationsincludedamoxicillin,500mg,three times a day for 10 days (erythromycin, 333 mg,three times a day for 10 days, was given to amoxicillin-sensitive subjects) and etodolac, 400 mg, three timesa day for 5 days.

The ePTFE sutures were removed at a postopera-tive visit 7 to 12 days after therapy had been carriedout. Radiographs were taken 3 to 7 months after theimplants had been placed to assess the readiness ofthe implants for uncovery and restoration. Implant un-covery was carried out in the conventional manner.

RESULTS

A total of 391 implants were inserted into 386 sub-jects. Implant size and distribution by treatment indi-cation are given in Table 1.

Regenerative therapy was performed at the time ofimplant placement in 371 sites. Twenty sites did notrequire regenerative therapy because the residual ex-traction socket had been obliterated by the implantthat was placed or the horizontal defect dimensionbetween the implant and extraction socket wall was<3.0 mm in all directions.

A total of 387 of the 391 implants were restoredwith abutments and single cemented crowns, and fourimplants were restored as components in a fixed splintby a variety of restorative dentists.

Soft tissue primary closure, defined as no implantor membrane exposure from the time of implant place-ment until second-stage implant surgery, was main-tained in 80 of 83 sites.

One implant was lost 6 weeks postoperatively. Atthat time, the patient presented with a fistula aroundthe implant and noticeable implant mobility. The im-plant was removed, and the socket was grafted. A newimplant was placed and restored, although it is not in-cluded in these statistics because it was not an implantplaced at the time of maxillary molar extraction. Asecond implant was mobile at the time of implantuncovery 6 months after insertion. This implant hadbeen placed in type IV bone and demonstrated ques-tionable primary stability at the time of insertion. Abreakdown of implant survival and failure by implantdimension is listed in Table 2.

Figure 6.A radiograph taken 38 months postrestoration demonstrates stabilityof the peri-implant crestal bone.

Figure 5.A hopeless maxillary molar was extracted, and the defect wasdebrided. An implant with a 4.1-mm–wide apex and a 6.5-mm–wideplatform was placed because of the lack of sufficient residualinterradicular bone for placement of an implant with a wider apex.Appropriate regenerative materials have been placed.

J Periodontol • February 2008 Fugazzotto

219

The restored implants were in function for up to 75months with a mean time of 40.3 months in function.The cumulative survival rate of the implants in functionwas 99.5% as assessed by the criteria of Albrektssonet al.10 (Table 3).

DISCUSSION

To be considered a viable treatment option at the timeof maxillary molar extraction, immediately placed im-plants must demonstrate predictability of osseointe-gration and ideal restorative positions comparable toimplants placed subsequent to maxillary molar ex-traction and regenerative therapy. The data presentedfulfill these requirements. All implants were placed inideal restorative positions within the residual interra-dicular bone. In addition, a cumulative survival rateof 99.5% for up to 75 months in function with a meantime of 40.3 months is at least comparable to pub-lished reports11,12 of implants placed in regeneratedor native host bone in maxillary molar sites.

Figure 10.An occlusal view shows the normal contours of the occlusal tables ofthe implant restorations.

Figure 9.A view of the restored implants 69 months after restoration.

Figure 7.A patient presents with a missing maxillary second molar and withhopeless prognoses for the maxillary first molar and second premolarbecause of root fractures. A peri-apical lesion is present around themesio-buccal root of the first molar. Additional bone height is requiredin the first and second molar positions to effect appropriate implantplacement.

Figure 8.Following extraction of the first molar and second premolar, a bonecore was imploded using a trephine and an osteotome in the positionof the second molar, the interradicular bone was manipulated asdescribed previously in the position of the first molar, and aconventional osteotomy was prepared in the second premolarposition. A 4.8-mm–wide parallel-walled implant with a 6.5-mm–wideplatform was placed in the second molar position. Adequateinterradicular bone was present in the first molar position forplacement of an implant with a 4.8-mm–wide apex and a6.5-mm–wide platform. An implant with a 3.3-mm–wide apex anda 4.8-mm–wide platform was placed in the second premolar position.

Implant Placement at the Time of Maxillary Molar Extraction Volume 79 • Number 2

220

Specific diagnostic and treatment protocols were ad-hered to strictly during performance of the documentedtherapies. Implantselectionwasnotgovernedby the re-sidual extraction socket morphology but rather by thedimensions of the remaining interradicular bone fol-lowing tooth sectioning and gentle removal of theindividual roots. Different rough-surface implant de-signs were used to help secure the implants withinthe manipulated interradicular bone. If primary stabil-ity could not be attained upon implant insertion, theimplantwasremoved.An implantofawiderdimension

Table 1.

Implant Distribution by Treatment Indication

4.8 mm

WN · 8

4.8 mm

WN · 10 4.8 TE WN · 10 4.8 TE WN · 12 4.1 TE WN · 10 4.1 TE WN · 12 Total

Additional heightrequired/wideinterradicular septum

41 3 3 0 0 0 47

Additional heightrequired/narrowinterradicular septum

0 0 0 0 107 2 109

No additional heightrequired/wide interradicularseptum

39 10 18 6 0 0 73

No additional heightrequired/narrowinterradicular septum

0 0 0 0 123 39 162

Total 80 13 21 6 230 41 391

WN = parallel walled 6.5-mm–wide platform implant with a 4.8-mm–wide body diameter; TE WN = an implant with 6.5-mm–wide platform and a taperedimplant body.

Figure 11.A patient presented with a hopeless prognosis for a maxillary firstmolar due to the presence of an intrafurcal fracture. Additional boneheight is required for appropriate implant placement. Following toothextraction, defect debridement, and manipulation of the interradicularbone as described previously, an implant is placed with a4.1-mm–wide apex and a 6.5-mm–wide platform. Inadequateinterradicular bone was present to allow placement of an implant witha wider apex.

Figure 12.An implant with a 4.1-mm–wide apex and a 6.5-mm–wide platformwas placed after implosion and manipulation of the interradicular bone.

Figure 13.Radiograph taken 61 months after implant restoration demonstratesstability of the crestal peri-implant bone.

J Periodontol • February 2008 Fugazzotto

221

was inserted to attain primary implant stability or thearea was grafted without implant placement, and animplant was placed in a subsequent surgical visit. Pri-mary stability of the inserted implant was confirmed atthe time of placement of the implant closure screw. Ifthe implantdemonstratedmobilityuponclosurescrewinsertion under gentle manual pressure, the implantwas removed.

All residual extraction socket defects with a hori-zontal defect dimension >3.0 mm were grafted withbovine bone matrix† or demineralized bone putty im-pregnated with cortical chips.‡ No horizontal defectdimensions >3.0 mm were left ungrafted. Titanium-reinforced or bioabsorbable covering membranes§

always were placed over grafted areas and securedwith fixation tacks to eliminate any question of mem-brane mobility. Finally, various flap designs and sutur-ing techniques were used to ensure attainment and

maintenance of soft tissue pri-mary closure throughout thecourse of regeneration. Suchprimary closure was maintainedin 80 of 83 sites.

Care was taken to insert im-plants whose outer diameters didnot impinge upon the residualbuccal and palatal alveolar boneplates, thus leaving room forclot formation. The one implantthat was mobile upon uncoverywas a tapered-end implant witha 4.8-mm apical diameter and a6.5-mmdiameter restorativeplat-form. At the time of its insertion,the residual buccal alveolar platewas macerated. This trauma tothe buccal bone may have beena factor in the loss of residualalveolar bone during healingand in the implant’s failure toattain osseointegration.

All implants were restoredwith crowns with normal occlu-sal table dimensions. Reducedocclusal tables were not usedin an attempt to decrease theforces placed upon the implantsunder function or parafunction.

Four of the implants placed atthe time of maxillary molar ex-traction were splinted to adjacentimplants. All of these cases weretreated early in the developmentalcurve of the described therapy.Currently, implants in maxillarymolar positions are never

splinted unless they are supporting a fixed prosthesiswith one or more pontics.

CONCLUSIONS

Implant placement at the time of maxillary molar re-moval with concomitant regeneration as needed andsubsequent restoration with unsplinted crowns is apredictable treatment modality. This approach offersnumerous potential advantages over other availabletechniques for the replacement of hopeless maxillarymolars with implant prostheses.

ACKNOWLEDGMENTS

No funding was received for this study. Dr. Fugazzottoreports no conflicts of interest related to this study.

Table 2.

Implant Survival and Failure in Function

Months in Function

Implant Size 0 to 12 13 to 24 25 to 36 37 to 48 Total

4.8 WN · 8 54 26 0 0 80

4.8 WN · 10 7 6 0 0 13

4.8 TE WN · 10 10 (1) 11 0 0 21

4.8 TE WN · 12 3 3 0 0 6

4.1 TE WN · 10 77 (1) 70 43 40 230

4.1 TE WN · 12 20 21 0 0 41

Total 171 (2) 137 43 40 391 (2)

() = failure during interval.WN = parallel walled 6.5-mm–wide platform implant with a 4.8-mm–wide body diameter; TE WN = animplant with 6.5-mm–wide platform and a tapered implant body.

Table 3.

Cumulative Implant Survival and Failure Rates in Function

Months After Abutment

Connection (N)

Implants at

Beginning of

Interval (N)

Implant Failures

During

Interval (N)

Interval

Failure

Rate (%)

Cumulative

Survival

Rate (%)

0 to 12 391 2 0.5 99.5

13 to 24 220 0 0 99.5

25 to 36 83 0 0 99.5

37 to 48 40 0 0 99.5

† Osteohealth, Shirley, NY.‡ Exactech, Gainesville, FL.§ W.L. Gore and Associates, Flagstaff, AZ.

Implant Placement at the Time of Maxillary Molar Extraction Volume 79 • Number 2

222

REFERENCES1. Nevins M, Mellonig JT. Enhancement of the damaged

edentulous ridge to receive dental implants: A combi-nation of allograft and a Gore-Tex membrane. Int J Peri-odontics Restorative Dent 1992;12:96-111.

2. Lekovic V, Kenney EB, Weinlaender M, et al. A boneregenerative approach to alveolar ridge maintenancefollowing tooth extraction. Report of 10 cases. J Peri-odontol 1997;68:563-570.

3. LekovicV,CamargoPM,KlokkevoldPR,etal.Preservationof alveolar bone in extraction sockets using bioabsorbablemembranes. J Periodontol 1998;69:1044-1049.

4. Arlin M. Immediate placement of dental implants intoextraction sockets: Surgically related difficulties. OralHealth 1993;83:23-27.

5. Schwartz-Arad D, Grossman Y, Chaushu G. The clinicaleffectiveness of implants placed immediately into freshextraction sites of molar teeth. J Periodontol 2000;71:839-844.

6. Hsu M-L, Chen F-C, Kao H-C, Cheng C-K. Influenceof off-axis loading of an anterior maxillary implant:A 3-dimensional finite element analysis. Int J OralMaxillofac Implants 2007;22:301-309.

7. Fugazzotto PA. Implant placement at the time ofmaxillary molar extraction: Technique and report ofpreliminary results of 83 sites. J Periodontol 2006;77:302-309.

8. Fugazzotto PA. Primary closure following guided boneregeneration therapy: Introduction of a new techniqueand reported preliminary results. J Periodontol 2006;77:1452-1457.

9. Fugazzotto PA. Report of 302 consecutive ridge aug-mentation procedures: Technical considerations andclinical results. Int J Oral Maxillofac Implants 1998;13:358-368.

10. Albrektsson T, Zarb G, Worthington P, Eriksson HA.Long-term efficacy of currently used dental implants:A review and proposed criteria of success. Int J OralMaxillofac Implants 1986;1:11-25.

11. Fugazzotto PA. Success and failure rates of osseointe-grated implants in function in regenerated bone for 72to 133 months. Int J Oral Maxillofac Implants 2005;20:77-83.

12. Fugazzotto PA, Vlassis J, Butler B. ITI implant use inprivate practice: Clinical results with 5,526 implantsfollowed up to 72 plus months in function. Int J OralMaxillofac Implants 2004;19:408-412.

Correspondence: Dr. Paul A. Fugazzotto, 25 High St., Milton,MA 02186. Fax: 617/696-6635; e-mail: progressiveperio@aol.com.

Submitted June 11, 2007; accepted for publication August8, 2007.

J Periodontol • February 2008 Fugazzotto

223