Socket Augmentation: Rationale andTechnique

Hom-Lay Wang, DDS, MSD,* Koichi Kiyonobu, DDS, PhD,† and Rodrigo F. Neiva, DDS‡

Tooth extraction results in alveo-lar bone loss as a result of re-sorption of the edentulous

ridge.1–4 An average of 40% to 60% oforiginal height and width is expectedto be lost after tooth extraction, withthe greatest loss happening within thefirst 2 years.5–9 This can negativelyinfluence bone volume that is neededfor future dental implant placement.Research has demonstrated that the al-veolar ridge at the maxillary anteriorarea can be reduced by 23% in the first6 months after exodontia, and an ad-ditional 11% in the following 5years.10 In the posterior mandible, re-sorption happens primarily in the buc-cal/labial direction, resulting in a lin-gual displacement of alveolar crest.10

The rate of reduction of residual alve-olar ridges has shown to be greater inmandibular (0.4 mm/year) than inmaxillary arches (0.1 mm/year).11 As aconsequence, alveolar ridge atrophymay prohibit optimal implant place-ment, compromising the final estheticand functional outcomes.12

Augmentation of the residual al-veolar socket at the time of tooth ex-traction (ie, socket augmentation,socket preservation, ridge preserva-tion) has been evaluated in many stud-ies.13–15 Multiple bone graft regimensand techniques have been suggested tominimize alveolar ridge atrophy and toevaluate new bone growth within ex-

traction sockets.16–18 Generally, theseprocedures are primarily aimed at pre-serving the current bone level andhopefully regenerating new bone.

This article presents the rationalebehind socket augmentation for futureimplant placement and describes atechnique that has shown to not onlyfacilitate tooth extraction with mini-mal damage to the surrounding ana-tomic structures, but also to improvealveolar bone quality and quantity.

RATIONALE

The rationale for alveolar ridgepreservation relies on the knowledgethat alveolar ridge resorption is an un-avoidable sequela of tooth loss.1 Lek-ovic et al. compared the outcome ofalveolar ridge preservation using ab-

sorbable barrier membranes and ex-tractions alone. At 6 months, signifi-cantly less crestal bone loss (�0.38mm vs. �1.50 mm), more internalsocket fill (�5.81 mm vs. �3.94 mm),and less horizontal ridge resorption(�1.31 mm vs. �4.56 mm) werefound in the membrane group than inthe control group.19 As this study sug-gested, successful early alveolar ridgeaugmentation (preservation) proce-dures may reduce, or eliminate, theneed for future ridge augmentation.

Bone healing and subsequent newbone formation after grafting takeplace through osteogenesis, osteoin-duction, and/or osteoconduction.20–22

Osteogenic graft materials supply via-ble osteoblasts that form new bone,whereas osteoinductive grafts stimu-

*Professor and Director of Graduate Periodontics, Departmentof Periodontics/Prevention/Geriatrics, School of Dentistry,University of Michigan, Ann Arbor, MI.†Private practice, Tokyo, Japan; and formal Visiting ResearchFellow, Department of Periodontics/Prevention/Geriatrics,School of Dentistry, University of Michigan, Ann Arbor, MI.‡Clinical Assistant Professor, Department ofPeriodontics/Prevention/Geriatrics, School of Dentistry,University of Michigan, Ann Arbor, MI.

ISSN 1056-6163/04/01304-286Implant DentistryVolume 13 • Number 4Copyright © 2004 by Lippincott Williams & Wilkins

DOI: 10.1097/01.id.0000148559.57890.86

The consequences of exodontiainclude alveolar bone resorption andultimately atrophy to basal bone of theedentulous site/ridges. Ridge resorp-tion proceeds quickly after tooth ex-traction and significantly reduces thepossibility of placing implants withoutgrafting procedures. The aims of thisarticle are to describe the rationalebehind alveolar ridge augmentationprocedures aimed at preserving orminimizing the edentulous ridge vol-ume loss. Because the goal of theseapproaches is to preserve bone, ex-odontia should be performed to pre-serve as much of the alveolar processas possible. After severance of thesupra- and subcrestal fibrous attach-ment using scalpels and periotomes,elevation of the tooth frequently al-lows extraction with minimal socketwall damage. Extraction sockets

should not be acutely infected and becompletely free of any soft tissue frag-ments before any grafting or augmen-tation is attempted. Socket bleedingthat mixes with the grafting materialseems essential for success of this pro-cedure. Various types of bone graftingmaterials have been suggested for thispurpose, and some have shown prom-ising results. Coverage of the graftedextraction site with wound dressingmaterials, coronal flap advancement,or even barrier membranes may en-hance wound stability and an undis-turbed healing process. Future con-trolled clinical trials are necessary todetermine the ideal regimen for socketaugmentation. (Implant Dent 2004;13:286–296)Key Words: alveolar ridge augmenta-tion, socket preservation, exodontia,dental implants

286 SOCKET AUGMENTATION

late pluripotential mesenchymal cellsto differentiate into osteoblasts thatcan form new bone. Osteoconductivegraft materials, however, merely act asa lattice for cell growth, permittingosteoblasts from the wound margins toinfiltrate the defect and migrate acrossthe graft.23 Autologous grafts are con-sidered to be the ideal material forbone grafting procedures because itpossesses osteogenic, osteoinductive,and osteoconductive properties.24

Transplantation of living cells in-creases the possibility of retained cellviability and graft revasculariza-tion.25–28 In addition, autologous graftsdo not present a risk of disease trans-mission because donor and recipientare the same individual.29 However,they do increase the risk of additionalpain, infection, and donor site morbid-ity because an additional surgical pro-cedure is necessary for harvesting.23

Hence, bone substitutes have gainedincreasing acceptance as alternativesto autologous bone for patients requir-ing bone augmentation in an effort todecrease the morbidity associated withautologous graft harvesting.30 Allo-grafts, xenografts, and alloplasts comein many forms, and data support theirsafety, clinical applicability, and lowantigenicity.31 Bone graft materialshave been used to augment bony de-fects adjacent to dental implants and torepair chronic extraction socket de-fects, with and without the use of bar-rier membranes.32–34 When combinedwith barrier membranes, bone graftmaterials have also shown to preventcollapse of the barrier membrane.35–38

Xenografts and alloplasts have alsobeen applied for correction of bonydefects adjacent to dental implants andalveolar ridge preservation before im-plant placement, showing promisingresults.39 Despite lack of osteoinduc-tivity, these materials have shown re-sults comparable with the resultsachieved with allografts.15 Becausethese materials are mineralized, theirosteoconductive property is enhancedas a result of formation of a more rigidscaffold for new bone formation.40–42

Because alveolar ridge atrophy isa common consequence of tooth loss,and various bone grafting materialshave shown positive results in manyclinical scenarios, attempts to graft ex-traction sockets to reduce alveolar

ridge atrophy have been made.43– 46

These grafting materials have shownto not only aid in osteoconduction ofosteogenic cells by preserving thespace and excluding unwanted cellsfrom the wound, but also to promoteformation new bone.47–50 Iasella et al.conducted a randomized, controlled,masked clinical trial in 24 patients.Subjects received either extractionalone or socket augmentation usingtetracycline hydrated freeze-driedbone allograft (FDBA) and a collagenmembrane. Histologic analysis dem-onstrated greater bone formation inaugmented sites after a 6-month heal-ing period. The most predictablemaintenance of ridge width, height,and position was achieved when asocket augmentation procedure wasused.50 However, some reports haveshown negative results when a alveo-lar ridge preservation was attempted,possibly as a result of use of inade-quate techniques and/or materials.51–54

For example, Zubillaga et al. evalu-ated a combination of demineralizedfreeze-dried bone allograft (Re-genafill; Regeneration Technologies,Inc., Alachua, FL) and a bioabsorb-able membrane (Resolut XT; W.L.Gore & Associates, Inc., Flagstaff,AZ) for socket augmentation. Thenegative results observed were attrib-uted to the slow resorption of the gel-atin carrier of the graft material.54

TECHNIQUE

After a complete medical historyhas been reviewed, and no contraindi-cations for a surgical procedure havebeen found, local anesthetic can beadministered. Excessive infiltration ofanesthetic agents containing high con-centrations of vasoconstrictor (ie,1:50,000 epinephrine) into the extrac-tion site is discouraged. Bone graftmaterials work best when thoroughlywetted by blood. Thus, bleeding fromthe site should be encouraged and notavoided.

Radiographic analysis of the sur-gical site should consider root mor-phology and surrounding anatomicstructures. After local anesthesia isachieved, sulcular incisions performedwith a 15-C scalpel will initiate rup-ture of the supracrestal attachment ap-paratus, which is composed of epithe-

lial and connective tissue attachmentsto the tooth surface. Utilization ofsharp instruments for this purposeminimizes trauma and loss of the gin-gival tissues.

Periotomes are then applied tosever the subcrestal attachment appa-ratus. Straight periotomes are indi-cated for use on single-rooted teeth,whereas angled periotomes allow ac-cess to posterior multirooted teeth.These instruments are used in a similarmanner for extraction of intact teeth orremoval of retained root fragments.The instrument is used first to com-plete rupture of the gingival fibers atthe cervical area of the tooth (Fig. 1a).During this procedure, the long axis ofthe blade should be angled convergingat approximately 20° from the toothlong axis. This maneuver ensures thatthe tip of the periotome blade is lo-cated within the crest of the alveolarbone only, thus preventing the bladefrom sliding out of the ridge and lac-erating the gingiva. The blade is thrustto the depth of the gingival sulcus andthe gingival attachment is severed cir-cumferentially. It is necessary to re-peat this procedure to ensure that allgingival fibers are severed. The instru-ment is then inserted into the peri-odontal ligament space and moved re-peatedly in a mesiodistal direction, onthe whole circumference of the root,severing the periodontal ligament im-mediately below the alveolar crest.The periotome is then pushed furtherdown into the periodontal ligament to-ward the root apex. It is possible toreach up to two thirds of the rootlength by repeatedly using this maneu-ver. With the completion of this pro-cedure, the tooth remains attached tothe alveolus only by the most apicalpart of the periodontal ligament. Ad-ditional elevation may be required ifsignificant tooth mobility is notachieved. A dental forceps should notbe applied until significant tooth mo-bility is achieved. It is then possible toextract the tooth without having to in-trude the dental forceps into the peri-odontal ligament space, thus avoidingdistortion or other damage to the alve-olar bone.55–57

After tooth removal, the socket isthoroughly curetted of all soft tissuedebris. Bleeding, if absent, should bestimulated from the osseous base. The

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key for maximum bone fill is adequatebleeding from the bone, because bloodcontains fundamental proteins andgrowth factors for bone healing.47,58,59

Profuse bleeding can be easilyachieved by scraping the walls of thesocket with either curettes or rotaryinstruments (Fig. 1b). This procedurealso triggers the regional acceleratoryphenomena (RAP), which is known tostimulate new bone formation andgraft incorporation.60–62

The selection of grafting materialshould be based on the following cri-teria: 1) have unlimited supply, 2) bebiologically inert (no immunologic re-action), 3) facilitated revasculariza-tion, 4) osteoconduction, and 5) becompletely replaced by new bone. Af-ter selection, the bone graft materialshould be inserted into the extractionsocket to provide a stable osteoinduc-tive/osteoconductive environmentduring the healing process. The mate-rial should be tamped down lightlyand overfill should be avoided. Ade-quate space between the graft particlesis critical to allow for revasculariza-tion to spread throughout the graft,bringing the proteins and growth fac-tors that are necessary for new bonegrowth.63–65 Overfilling the socket willonly result in sequestration of thecoronal graft particles, possibly lead-ing to development of an infectioussource that may negatively influenceosseous formation.66 Only the apicaltwo thirds of the socket should befilled with bone grafting material (Fig.

1c). If this rule is followed, the mostcoronal aspect of the graft stays at orslightly below the osseous crest, andthe remaining coronal one third of thesocket is mainly composed of gingivaltissue. An absorbable collagen dress-ing material (CollaPlug; Zimmer Den-tal, Inc., Carlsbad, CA) is then placedto seal the coronal portion of thesocket (Fig. 1d). This material pro-vides stabilization for the treatmentsite. Collagen dressing materials arepreferable because of their physiolog-ical absorption process and high bio-compatibility with oral tissues. In ad-dition, collagen is a hemostatic agentand possesses the ability to stimulateplatelet aggregation and to enhance fi-brin linkage, which may lead to initialclot formation, stability, and matura-tion.67 Furthermore, collagen has beendemonstrated to be chemotactic for fi-broblasts in vitro.68 This propertycould enhance cell migration and pro-mote primary wound coverage that isfundamental for bone growth. A cross-mattress suture is then used to securethe collagen dressing material in thesocket for the initial 14 days of thehealing process (Fig. 1e). Ovate fixedor removable pontics may be used toprovide support to both interdental pa-pillae and facilitate development of amore esthetically pleasing soft tissueprofile (Fig. 1f). A step-by-step illus-tration of using this technique to aug-ment sockets is shown in Figures 2and 3.

Postoperative care should include

rinsing twice daily with warm salt wa-ter for the first 2 weeks. Prescriptionof antibiotics should be limited tocases presenting signs of active infec-tion. Systemic antibiotic prophylaxisis generally not recommended as aresult of the odontogenic nature of themajority of chronic infections. Hence,the source of infection is removed dur-ing exodontia, eliminating the need ofadditional antibiotic coverage. At 14days, profuse granulation of soft tissuefrom the margins of the wound is acommon finding, partially or com-pletely covering the grafted area. Thehealing process should be monitoredradiographically and implant place-ment can usually be performed 90 to120 days after alveolar ridge preserva-tion procedures. If a radiographic im-age shows immature bone formation atthis time, implant placement should bepostponed until normal radiodensity isobserved. Radiolucencies persistingfor more than 180 days are indicativeof inadequate graft incorporation, fre-quently requiring an additional proce-dure for debridement of the graft par-ticles and possibly a new graftingprocedure.

DISCUSSION

Traditional tooth extraction isknown to result in alveolar bone lossas a result of atrophy of the edentulousridge.1–4 Before implant therapy wasintroduced, the concern was often re-lated to stability of removable prosthe-ses. However, atrophic ridges can neg-atively influence or even prohibitimplant placement and often result inpoor esthetic outcomes. Ridge resorp-tion caused by tooth extraction shouldbe reduced or eliminated.5–9

Recently, a socket preservationtechnique named “Bio-Col” was intro-duced.66 This technique involves: 1)atraumatic tooth extraction followedby socket curettage and cortical socketperforation, 2) socket grafting withbovine hydroxyapatite (HA) (Bio-Oss;Osteohealth Co, Shirley, NY), 3)placement of an absorbable collagendressing (CollaPlug), and 4) socketsealing with an impervious tissue glue(Isodent; Ellman International,Hewlett, NY). An interim ovate ponticform of provisional restoration is thenfabricated to replicate the contours of

Fig. 1. (a) Atraumatic tooth extraction. (b) Bleeding is stimulated with curettes or rotaryinstruments. (c) Bone graft fills two thirds of the socket depth. (d) Wound dressing material fillsthe remaining one third of the socket. (e) A crossmattress suture is applied. (f) Ovate ponticsare used for soft tissue development.

288 SOCKET AUGMENTATION

the extracted tooth and to facilitatesoft tissue profile. The authors claimthat this technique 1) prevents loss of

both hard and soft tissues, 2) reducesthe number of surgical interventions,and 3) provides optimum esthetics

with greater predictability. However,no controlled studies have been con-ducted to confirm these findings. Thetechnique presented in this article hasbeen extensively used in our institu-tion. Positive outcomes have beenconstantly achieved with minimalmorphologic changes noticeable up to6 months after exodontia. Augmentedsockets have shown not only adequatemorphology, but also density; both ofwhich are noticeable during implantosteotomy preparation. As a conse-quence, soft tissue profile has beenconstantly preserved, maximizing theesthetic outcome. Future investiga-tions should provide scientific evi-dence of our experiences.

Many bone grafting materialshave been suggested for socket aug-mentation.69–73 These include autoge-nous bone, demineralized freeze-driedbone allograft (DFDBA),74 mineral-ized freeze-dried bone allograft(FDBA),75 bovine hydroxyapatite(HA)10; and alloplasts.14 Becker et al.evaluated the bone-forming capacityof DFDBA in extraction sockets.74

The sites were reentered for the pur-poses of obtaining biopsies of thegrafted areas. The biopsies showedthat DFDBA-grafted sites had no evi-dence of new bone formation and thatthere was no evidence of osteoclasticresorption of the graft particles,whereas the autograft-treated sites re-vealed vascular channels with wovenand lamellar bone. The evidence sug-gests that DFDBA may not be a goodmaterial for socket augmentation.74 Apotential delay in osteogenic cell in-growth has also been observed when ademineralized bone matrix (GraftonDBM Plugs; Osteotech, Inc., Eaton-town, NJ) was used for socket aug-mentation.76 However, Brugnami et al.combined DFDBA with barrier mem-branes and found positive results, sug-gesting that barrier membranes mayovercome possible deficiencies of thisgrafting material.32 Recently, a humanbone mineralized graft (Puros; Zim-mer Dental, Carlsbad, CA) was intro-duced. It constitutes a mineralizedbone allograft material processedthrough unique solvent-preserved pro-cesses for tissue preservation and viralinactivation, which differ from thestandard cryopreserved process. Datahave demonstrated that after standard

Fig. 2. (a) Preoperative view. (b) Periotomes facilitate rupture of the supracrestal attachmentapparatus. (c) Tooth extraction occurs with minimal trauma to the surrounding tissues. (d) Thesocket is free of infection and presents profuse bleeding.

Fig. 2e. (e) The bone graft material is inserted into the extraction socket (Puros; ZimmerDental, Carlsbad, CA). (f) A wound dressing material (CollaPlug; Zimmer Dental) covers theaugmented extraction socket. (g) A crossmattress suture is placed to stabilize the wound. (h)An ovate pontic is used for soft tissue development. (i) Postoperative view 14 days after socketaugmentation. (j) Reentry 120 days later showing complete bone fill.

IMPLANT DENTISTRY / VOLUME 13, NUMBER 4 2004 289

tissue bank processing and limitedgamma radiation, the bone appears toremain intact, providing excellentbone matrix and load-bearing capabil-ities.77,78 Research has demonstratedlamellar bone formation as quickly as15 days after implantation of this ma-terial in the tibia of rabbits and almostcomplete disappearance in 60 days.79

These findings suggest that this mate-rial may be a good alternative forsocket augmentation procedures. Our

group uses either FDBA or humanmineralized bone as the primary bonegraft for this type of procedure. Thesematerials have optimal osteoconduc-tive properties and may also be os-teoinductive by releasing bone mor-phogenic proteins (BMPs), whichcould induce osteogenesis from sur-rounding bone.80–84 In addition, thesematerials have shown to be completelyresorbed and consequently replacedwith host bone within 2 to 4 months.85

This facilitates future implant place-ment.79 Future studies in this area areneeded.

The use of barrier membranes insocket augmentation procedures hasalso been evaluated. Lekovic et al. ob-served the clinical effectiveness ofbarrier membranes in preserving alve-olar ridges after tooth extraction. Re-sults showed that membrane-coveredsites presented with significantly lessridge atrophy than control sites. Theauthors suggested that treatment of ex-traction sockets with membranes isvaluable in preserving alveolar bone inextraction sockets and preventing al-veolar ridge defects.86 Difficulties as-sociated with barrier membrane useduring socket augmentation include:1) the potential reduction of keratin-ized gingiva, 2) alterations of gingivalcontours, and 3) migration of the mu-cogingival junction, as a result ofcoronal displacement of the flap toachieve soft tissue closure over themembrane.87–90 Even with these draw-backs, some studies have demon-strated success in the use of a varietyof membranes for socket augmenta-tion, including nonabsorbable, absorb-able, and acellular dermal allo-grafts.53,91–93 Fowler et al. usedacellular dermal matrix (AlloDerm;Lifecore Biomedical, Oral RestorativeDivision, Chaska, MN) as a barriermembrane with a demineralizedfreeze-dried bone allograft for ridgepreservation. A series of cases demon-strated an acceptable esthetic resultwith no apparent loss of ridge heightor width. The 2 graft materials werewell accepted by the body and healingwas rapid and without significant dis-comfort.18 Reports in the literaturehave also suggested use of other ma-terials such as xenografts and allo-plasts with varying results.93–95 How-ever, these reports were primarily casestudy series.

CONCLUSION

Future controlled clinical trials areencouraged to validate the findings ofthe technique presented in this articleto provide needed scientific evidence.

DISCLOSURE

The authors do not have any fi-nancial interests, either directly or in-

Fig. 3. (a) Periotomes are progressively inserted around the whole circumference of the tooth.(b) Atraumatic tooth extraction. (c) The socket is free of infection and presents profuse bleed-ing. (d) The bone graft material is inserted into the extraction socket (Puros; Zimmer Dental,Carlsbad, CA).

Fig. 3. (e) A wound dressing material (CollaPlug; Zimmer Dental) covers the augmentedextraction socket. (f) An ovate pontic is used for soft tissue development. (g) Adequate ridgewidth 90 days after exodontia. (h) Soft tissue profile shows fully preserved 90 days after toothextraction.

290 SOCKET AUGMENTATION

directly, in the products listed in thisstudy.

ACKNOWLEDGMENTS

This study was partially supported bythe University of Michigan, Periodon-tal Graduate Student Research Fund.

REFERENCES

1. Bays R. The pathophysiology andanatomy of edentulous bone loss. Recon-structive Preprosthetic Oral and Maxillofa-cial Surgery. 1986;1:1–17.

2. Mecall RA, Rosenfeld AL. Influenceof residual ridge resorption patterns on fix-ture placement and tooth position, Part III:presurgical assessment of ridge augmen-tation requirements. Int J Periodontics Re-storative Dent. 1996;16:322–337.

3. Mecall RA, Rosenfeld AL. The influ-ence of residual ridge resorption patternson implant fixture placement and tooth po-sition. 2. Presurgical determination ofprosthesis type and design. Int J Periodon-tics Restorative Dent. 1992;12:32–51.

4. Mecall RA, Rosenfeld AL. Influenceof residual ridge resorption patterns on im-plant fixture placement and tooth position.1. Int J Periodontics Restorative Dent.1991;11:8–23.

5. Sevor JJ, Meffert R. Placement ofimplants into fresh extraction sites using aresorbable collagen membrane: case re-ports. Pract Periodontics Aesthet Dent.1992;4:35–41.

6. Polizzi G, Grunder U, Goene R, etal. Immediate and delayed implant place-ment into extraction sockets: a 5-year re-port. Clin Implant Dent Relat Res. 2000;2:93–99.

7. Grunder U, Polizzi G, Goene R, etal. A 3-year prospective multicenterfollow-up report on the immediate anddelayed-immediate placement of implants.Int J Oral Maxillofac Implants. 1999;14:210–216.

8. Werbitt MJ, Goldberg PV. The im-mediate implant: bone preservation andbone regeneration. Int J Periodontics Re-storative Dent. 1992;12:206–217.

9. Werbitt MJ, Goldberg PV. Immedi-ate implantation. Preservation of bone vol-ume and osseous regeneration. J Peri-odontol. 1991;10:157–166.

10. Artzi Z, Tal H, Dayan D. Porous bo-vine bone mineral in healing of human ex-traction sockets. Part 1: histomorphomet-ric evaluations at 9 months. J Periodontol.2000;71:1015–1023.

11. Nemcovsky CE, Serfaty V. Alveolarridge preservation following extraction ofmaxillary anterior teeth. Report on 23 con-secutive cases. J Periodontol. 1996;67:390–395.

12. Howell TH, Fiorellini J, Jones A, etal. A feasibility study evaluating rhBMP-2/

absorbable collagen sponge device for lo-cal alveolar ridge preservation or augmen-tation. Int J Periodontics Restorative Dent.1997;17:124–139.

13. Ashman A, Lopinto J. Placement ofimplants into ridges grafted with BioplantHTR synthetic bone: histological long-termcase history reports. J Oral Implantol.2000;26:276–290.

14. Froum S, Orlowski W. Ridge pres-ervation utilizing an alloplast prior to im-plant placement—clinical and histologicalcase reports. Pract Periodontics AesthetDent. 2000;12:393–402; quiz 404.

15. Froum S, Cho SC, Rosenberg E, etal. Histological comparison of healing ex-traction sockets implanted with bioactiveglass or demineralized freeze-dried boneallograft: a pilot study. J Periodontol. 2002;73:94–102.

16. Bartee BK. Extraction site recon-struction for alveolar ridge preservation.Part 1: rationale and materials selection.J Oral Implantol. 2001;27:187–193.

17. Becker W, Hujoel P, Becker BE. Ef-fect of barrier membranes and autologousbone grafts on ridge width preservationaround implants. Clin Implant Dent RelatRes. 2002;4:143–149.

18. Fowler EB, Breault LG, Rebitski G.Ridge preservation utilizing an acellulardermal allograft and demineralized freeze-dried bone allograft: Part I. A report of 2cases. J Periodontol. 2000;71:1353–1359.

19. Lekovic V, Kenney EB, Weinlae-nder M, et al. A bone regenerative ap-proach to alveolar ridge maintenance fol-lowing tooth extraction. Report of 10cases. J Periodontol. 1997;68:563–570.

20. Marx RE, Snyder RM, Kline SN.Cellular survival of human marrow duringplacement of marrow-cancellous bonegrafts. J Oral Surg. 1979;37:712–717.

21. Urist MR, Granstein R, Nogami H,et al. Transmembrane bone morphogene-sis across multiple-walled diffusion cham-bers. New evidence for a diffusible bonemorphogenetic property. Arch Surg. 1977;112:612.

22. Burwell RG. Osteogenesis in can-cellous bone grafts: considered in terms ofcellular changes, basic mechanisms andthe perspective of growth-control and itspossible aberrations. Clin Orthop. 1965;40:35.

23. Feinberg SE, Fonseca RJ. Biologicaspects of transplantation of grafts. In:Davis WH, ed. Reconstructive Prepros-thetic Oral and Maxillofacial Surgery, 1sted. Philadelphia: WB Saunders; 1986.

24. Schallhorn RG. The use of autoge-nous hip marrow biopsy implants for bonycrater defects. J Periodontol. 1968;39:145–147.

25. Maatz R, Lentz W, Graf R. Experi-mental principles in transplantation of pre-served bones. Langenbecks Arch Klin ChirVer Dtsch Z Chir. 1952;273:850–855.

26. Maatz R, Lentz W, Graf R. Bonetissue formation by preserved particles;bone banks. Zentralbl Chir. 1952;77:1376–1382.

27. Maatz R. Biological principles ofhealing of bone wounds. Dtsch Med J.1953;4:255–260.

28. Maatz R, Lentz W, Graf R. Spon-giosa test of bone grafts for transplanta-tion. J Bone Joint Surg [Am]. 1954;36:721–731.

29. Goldberg VM, Stevenson S. Natu-ral history of autografts and allografts. ClinOrthop. 1987;225:7–15.

30. Russell JL. Grafton demineralizedbone matrix: performance consistency,utility, and value. Tissue Engineering.2000;6:435–440.

31. Buck BE, Malinin TI. Human boneand tissue allografts. Preparation andsafety. Clin Orthop. 1994:8–17.

32. Brugnami F, Then PR, Moroi H, etal. GBR in human extraction sockets andridge defects prior to implant placement:clinical results and histologic evidence ofosteoblastic and osteoclastic activities inDFDBA. Int J Periodontics RestorativeDent. 1999;19:259–267.

33. Kassolis JD, Rosen PS, ReynoldsMA. Alveolar ridge and sinus augmentationutilizing platelet-rich plasma in combina-tion with freeze-dried bone allograft: caseseries. J Periodontol. 2000;71:1654–1661.

34. Simion M, Trisi P, Piattelli A. GBRwith an e-PTFE membrane associated withDFDBA: histologic and histochemical anal-ysis in a human implant retrieved after 4years of loading. Int J Periodontics Restor-ative Dent. 1996;16:338–347.

35. Nevins M, Mellonig JT. Enhance-ment of the damaged edentulous ridge toreceive dental implants: a combination ofallograft and the GORE-TEX membrane.Int J Periodontics Restorative Dent. 1992;12:96–111.

36. Nevins M, Mellonig JT. The advan-tages of localized ridge augmentation priorto implant placement: a staged event. Int JPeriodontics Restorative Dent. 1994;14:96–111.

37. Mellonig JT, Nevins M. Guidedbone regeneration of bone defects associ-ated with implants: an evidence-basedoutcome assessment. Int J PeriodonticsRestorative Dent. 1995;15:168–185.

38. Mellonig JT, Nevins M, Sanchez R.Evaluation of a bioabsorbable physicalbarrier for guided bone regeneration. PartI. Material alone. Int J Periodontics Restor-ative Dent. 1998;18:139–149.

39. Smiler DG. Comparison of anor-ganic bovine mineral with and without syn-thetic peptide in a sinus elevation: a casestudy. Implant Dent. 2001;10:139–142.

40. Camargo PM, Lekovic V, Weinlae-nder M, et al. Influence of bioactive glasson changes in alveolar process dimensionsafter exodontia. Oral Surg Oral Med Oral

IMPLANT DENTISTRY / VOLUME 13, NUMBER 4 2004 291

Pathol Oral Radiol Endod. 2000;90:581–586.

41. Aichelmann-Reidy ME, Yukna RA.Bone replacement grafts. The bone substi-tutes. Dent Clin North Am. 1998;42:491–503.

42. Yukna RA, Evans GH, Aichelmann-Reidy MB, et al. Clinical comparison of bio-active glass bone replacement graft mate-rial and expanded polytetrafluoroethylenebarrier membrane in treating human man-dibular molar class II furcations. J Peri-odontol. 2001;72:125–133.

43. Hirai S. Evaluation of hydroxyapa-tite ceramics implants in the fresh extrac-tion sockets for the alveolar ridge preser-vation. Nippon Hotetsu Shika GakkaiZasshi. 1988;32:920–935.

44. Cranin AN, Simons A, Klein M, etal. The use of a particulate, microporous,calcified copolymer as a ridge mainte-nance device in dogs. J Vet Dent. 1995;12:53–58.

45. Ashman A. Ridge preservation: thenew buzzword in dentistry. Implant Soc.1995;6:1–7.

46. Bartee BK. A simplified techniquefor ridge preservation after tooth extrac-tion. Dent Today. 1995;14:62–77.

47. Becker W, Urist M, Becker BE, etal. Clinical and histologic observations ofsites implanted with intraoral autologousbone grafts or allografts. 15 human casereports. J Periodontol. 1996;67:1025–1033.

48. Pinholt EM, Haanaes HR, RoervikM, et al. Alveolar ridge augmentation byosteoinductive materials in goats. Scand JDent Res. 1992;100:361–365.

49. Pinholt EM, Bang G, Haanaes HR.Alveolar ridge augmentation by osteoin-duction in rats. Scand J Dent Res. 1990;98:434–441.

50. Iasella JM, Greenwell H, Miller RL,et al. Ridge preservation with freeze-driedbone allograft and a collagen membranecompared to extraction alone for implantsite development: a clinical and histologicstudy in humans. J Periodontol. 2003;74:990–999.

51. Cohen ES. Ridge enhancementand socket preservation utilizing the sub-epithelial connective tissue graft: a case re-port. Pract Periodontics Aesthet Dent.1995;7:53–58; quiz 60.

52. Tal H. Autogenous masticatorymucosal grafts in extraction socket sealprocedures: a comparison between sock-ets grafted with demineralized freeze-driedbone and deproteinized bovine bone min-eral. Clin Oral Implants Res. 1999;10:289–296.

53. Zitzmann NU, Scharer P, MarinelloCP. Factors influencing the success ofGBR. Smoking, timing of implant place-ment, implant location, bone quality andprovisional restoration. J Clin Periodontol.1999;26:673–682.

54. Zubillaga G, Von Hagen S, Simon

BI, et al. Changes in alveolar bone heightand width following post-extraction ridgeaugmentation using a fixed bioabsorbablemembrane and demineralized freeze-driedbone osteoinductive graft. J Periodontol.2003;74:965–975.

55. Quinn JH, Kent JN. Alveolar ridgemaintenance with solid nonporous hy-droxylapatite root implants. Oral Surg OralMed Oral Pathol. 1984;58:511–521.

56. Quinn JH, Kent JN, Hunter RG, etal. Preservation of the alveolar ridge withhydroxylapatite tooth root substitutes.J Am Dent Assoc. 1985;110:189–193.

57. Kentros GA, Filler SJ, RothsteinSS. Six month evaluation of particulate Du-rapatite in extraction sockets for the pres-ervation of the alveolar ridge. Implantolo-gist. 1985;3:53–62.

58. Jensen OT, Greer RO Jr, JohnsonL, et al. Vertical guided bone-graft aug-mentation in a new canine mandibularmodel. Int J Oral Maxillofac Implants.1995;10:335–344.

59. Kay SA, Wisner-Lynch L, MarxerM, et al. Guided bone regeneration: inte-gration of a resorbable membrane and abone graft material. Pract PeriodonticsAesthet Dent. 1997;9:185–194; quiz 196.

60. Trevisan C, Ortolani S, MonteleoneM, et al. Regional migratory osteoporosis:a pathogenetic hypothesis based on threecases and a review of the literature. ClinRheumatol. 2002;21:418–425.

61. Melsen B. Tissue reaction to orth-odontic tooth movement—a new para-digm. Eur J Orthod. 2001;23:671–681.

62. Melsen B. Biological reaction of al-veolar bone to orthodontic tooth move-ment. Angle Orthod. 1999;69:151–158.

63. Becker W, Lynch SE, Lekholm U,et al. A comparison of ePTFE membranesalone or in combination with platelet-derived growth factors and insulin-likegrowth factor-I or demineralized freeze-dried bone in promoting bone formationaround immediate extraction socket im-plants. J Periodontol. 1992;63:929–940.

64. Valentin-Opran A, Wozney J,Csimma C, et al. Clinical evaluation of re-combinant human bone morphogeneticprotein-2. Clin Orthop. 2002:110–120.

65. Mellonig JT. Bone allografts in peri-odontal therapy. Clin Orthop. 1996:116–125.

66. Sclar AG. Preserving alveolar ridgeanatomy following tooth removal in con-junction with immediate implant place-ment. The Bio-Col technique. Atlas OralMaxillofac Surg Clin North Am. 1999;7:39–59.

67. Sableman E. Biology, Biotechnol-ogy, and Biocompatibility of Collagen. Bio-compatibility of Tissue Analogs, 1st ed.Boca Raton, FL: CRC Press; 1985:27.

68. Postlethwaite AE, Seyer JM, KangAH. Chemotactic attraction of human fi-broblasts to type I, II, and III collagens and

collagen-derived peptides. Proc Natl AcadSci U S A. 1978;75:871–875.

69. Gross J. Ridge preservation usingHTR synthetic bone following tooth extrac-tion. Gen Dent. 1995;43:364–367.

70. Serino G, Biancu S, Iezzi G, et al.Ridge preservation following tooth extrac-tion using a polylactide and polyglycolidesponge as space filler: a clinical and histo-logical study in humans. Clin Oral ImplantsRes. 2003;14:651–658.

71. Sy IP. Alveolar ridge preservationusing a bioactive glass particulate graft inextraction site defects. Gen Dent. 2002;50:66–68.

72. Yukna RA, Castellon P, Saenz-Nasr AM, et al. Evaluation of hard tissuereplacement composite graft material as aridge preservation/augmentation materialin conjunction with immediatehydroxyapatite-coated dental implants. JPeriodontol. 2003;74:679–686.

73. Vasilic N, Henderson R, JorgensonT, et al. The use of bovine porous bonemineral in combination with collagen mem-brane or autologous fibrinogen/fibronectinsystem for ridge preservation followingtooth extraction. J Okla Dent Assoc. 2003;93:33–38.

74. Becker W, Becker BE, Caffesse R.A comparison of demineralized freeze-dried bone and autologous bone to inducebone formation in human extraction sock-ets. J Periodontol. 1994;65:1128–1133.

75. Feuille F, Knapp CI, Brunsvold MA,et al. Clinical and histologic evaluation ofbone-replacement grafts in the treatmentof localized alveolar ridge defects. Part 1:mineralized freeze-dried bone allograft. IntJ Periodontics Restorative Dent. 2003;23:29–35.

76. Korsnes J. Effects of a demineral-ized bone matrix on alveolar ridge preser-vation. Orban Competition, AmericanAcademy of Periodontology, AnnualMeeting; September 2003.

77. Scharf H. Humane Tibialis-anterior-Sehnen als losungsmittelkonser-ciertes Transplantat fur den Kreuzbander-satz. Universitat Ulm. 1990:23–28.

78. Gunther KP, Scharf H-P, PeschH-J, et al. Osteointegration of solvent-preserved bone transplants in an animalmodel. Osteologie. 1996;5:4–12.

79. Dalkyz M, Ozcan A, Yapar M, et al.Evaluation of the effects of different bioma-terials on bone defects. Implant Dent.2000;9:226–235.

80. Urist MR. Bone: formation by auto-induction. Science. 1965;150:893–899.

81. Urist MR, Silverman BF, Buring K,et al. The bone induction principle. Clin Or-thop. 1967;53:243–283.

82. Urist MR, Dowell TA, Hay PH, et al.Inductive substrates for bone formation.Clin Orthop. 1968;59:59–96.

83. Urist MR, Iwata H. Preservationand biodegradation of the morphogenetic

292 SOCKET AUGMENTATION

property of bone matrix. J Theor Biol.1973;38:155–167.

84. Urist MR, Iwata H, Ceccotti PL, etal. Bone morphogenesis in implants of in-soluble bone gelatin. Proc Natl Acad Sci US A. 1973;70:3511–3515.

85. Wang HL, Misch C, Neiva RF.’Sandwich’ bone augmentation technique:rationale and report of pilot cases. Int JPeriodontics Restorative Dent. 2004;24:232–245.

86. Lekovic V, Camargo PM,Klokkevold PR, et al. Preservation of alve-olar bone in extraction sockets using bio-absorbable membranes. J Periodontol.1998;69:1044–1049.

87. Wang HL, Al-Shammari KF.Guided tissue regeneration-based rootcoverage utilizing collagen membranes:technique and case reports. QuintessenceInt. 2002;33:715–721.

88. Wang HL, Kimble K, Eber R. Use ofbone grafts for the enhancement of a GTR-

based root coverage procedure: a pilotcase study. Int J Periodontics RestorativeDent. 2002;22:119–127.

89. Wang HL, Bunyaratavej P, LabadieM, et al. Comparison of 2 clinical tech-niques for treatment of gingival recession.J Periodontol. 2001;72:1301–1311.

90. Wang HL, Carroll MJ. Guided boneregeneration using bone grafts and colla-gen membranes. Quintessence Int. 2001;32:504–515.

91. Bartee BK. Extraction site recon-struction for alveolar ridge preservation.Part 2: membrane-assisted surgicaltechnique. J Oral Implantol. 2001;27:194–197.

92. Yang J, Lee HM, Vernino A. Ridgepreservation of dentition with severe peri-odontitis. Compend Contin Educ Dent.2000;21:579–583; quiz 584.

93. Ashman A. Postextraction ridgepreservation using a synthetic alloplast.Implant Dent. 2000;9:168–176.

94. Oikarinen KS, Sandor GK, Kainu-lainen VT, et al. Augmentation of the nar-row traumatized anterior alveolar ridge tofacilitate dental implant placement. DentTraumatol. 2003;19:19–29.

95. Wiesen M, Kitzis R. Preservation ofthe alveolar ridge at implant sites. Peri-odontal Clin Investig. 1998;20:17–20.

Reprint requests and correspondence to:Hom-Lay Wang, DDS, MSDProfessor and Director of GraduatePeriodonticsDepartment ofPeriodontics/Prevention/GeriatricsUniversity of Michigan School of Dentistry1011 North University AvenueAnn Arbor, MI 48109-1078Phone: (734) 763-3383Fax: (734) 936-0374E-mail: homlay@umich.edu

IMPLANT DENTISTRY / VOLUME 13, NUMBER 4 2004 293

Abstract Translations [German, Spanish, Portugese, Japanese]

AUTOR(EN): Hom-Lay Wang, D.D.S.,M.S.D.*, Koichi Kiyonobu, D.D.S., Ph.D.**,und Rodrigo F. Neiva, D.D.S.***. *Professorund Leiter des Graduiertenkollegs Orthodon-tie, Abteilung fur Orthodontie/Pravention/Geriatrie, zahnmedizinische Fakultat, Univer-sitat von Michigan, Anna Arbor, MI. **Privatpraktizierender Arzt, Tokio, Japan. Mitglieddes Forschungsteams mit Gaststatus, Abtei-lung fur Orthodontie/Pravention/Geriatrie,zahnmedizinische Fakultat, Universitat vonMichigan, Anna Arbor, MI. *** KlinischerAssistenzprofessor, Abteilung fur Orthodontie/Pravention/Geriatrie, zahnmedizinischeFakultat, Universitat von Michigan, Anna Ar-bor, MI. Schriftverkehr: Hom-Lay Wang,DDS, MSD, Professor und Leiter des Gradui-ertenkollegs Orthodontie (Professor and Di-rector of Graduate Periodontics), Abteilungfur Orthodontie/Pravention/Geriatrie (Dept.of Periodontics/Prevention/Geriatrics), Uni-versitat von Michigan, zahnmedizinischeFakultat (University of Michigan School ofDentistry), 1011 North University Avenue,Ann Arbor, Michigan 48109 - 1078, USA.Telefon: (734) 763 - 3383 Fax: (734) 936–0374. eMail: homlay@umich.edu

Verstarkung der Zahnhohle: Grundprinzipien und Methodik

ZUSAMMENFASSUNG: Zu den Folgen der Zahnextraktion gehoren die Resorption desAlveolarknochens und letztendlich eine Atrophie des Basalknochens im zahnlosen Kief-erbereich bzw. Zahnkamm. Die Resorption des Kamms geht erfahrungsgema� nacherfolgter Zahnextraktion schnell vonstatten und verringert damit die Chancen fur eineerfolgreiche Implantierung ohne vorherige Transplantierungsnotwendigkeit. Die vorlieg-ende Arbeit konzentriert sich auf eine Beschreibung der den Behandlungsschritten zurAnreicherung des Zahnkamms zu Grunde liegenden Grundprinzipien. Die Behandlung ansich zielt auf eine Erhaltung des zahnlosen Kammvolumens oder zumindest doch auf eineVerringerung des entstehenden Volumenverlustes ab. Da jeder Behandlungsansatz letz-tendlich die Erhaltung des vorhandenen Knochengewebes vorsieht, sollte bei der Zah-nextraktion versucht werden, das maximale Ma� des Alveolarprozesses zu erhalten. NachTrennung des uber und unter dem Kamm gelegenen fibrosen Gewebes mittels Skalpellund Periotom kann eine Anhebung des Zahnes die Extraktion mit nur minimalen Scha-digungen an der Wand der Zahnpfanne begunstigen. Die Extraktionshohlen sollten ge-nerell immer infektionsfrei und ohne Ruckstande von Weichgewebsteilen gehalten wer-den, bevor der Versuch einer Transplantierung oder Gewebsanreicherung unternommenwird. Entstehen Blutungen in der Zahnhohle, konnen sich diese mit dem zur Transplan-tation vorgesehenen Material vermischen und so den Gesamterfolg der Behandlunggefahrden. Hier empfiehlt es sich, die mit Transplantat versehene Extraktionsstelle mitWundverbandmaterialien zu bedecken, den Zahnkronenlappen bedeckend vorzuziehenoder sogar Barriermembrane vorzusehen, um somit die Wundstabilitat zu erhohen undeinen ungehinderten Heilungsprozess zu ermoglichen. Fur die Bestimmung der idealenMa�nahmen zur Zahnhohlenanreicherung mussten kontrollierte klinische Versuchsreihendurchgefuhrt werden.

SCHLUSSELWORTER: Verstarkung des Alveolarkammes. Erhaltung der Zahnhohle,Zahnextraktion, Zahnimplantate

AUTOR(ES): Hom-Lay Wang, D.D.S., M.S.D.*,Koichi Kiyonobu, D.D.S., Ph.D.** y Rodrigo F.Neiva, D.D.S.***. *Profesor y Director de Period-oncia para Graduados, Departamento de Peri-odontica/Prevencion/Geriatrica, Facultad de Od-ontologıa, Universidad de Michigan, Ann Arbor,MI. **Practica Privada, Tokio, Japon. Ex-Investigador Visitante, Departamento de Periodon-tica/Prevencion/Geriatrica, Facultad de Odontolo-gıa, Universidad de Michigan, Ann Arbor, MI.***Profesor Clınico Asistente, Departamento dePeriodontica/Prevencion/Geriatrica, Facultad deOdontologıa, Universidad de Michigan, Ann Ar-bor, MI. Correspondencia a: Hom-Lay Wang,DDS, MSD, Profesor y Director of Graduate Pe-riodontics, Department of Periodontics/Prevention/Geriatrics, University of Michigan School of Den-tistry, 1011 North University Avenue, Ann Arbor,Michigan 48109-1078, U.S.A. Telefono: (734) 763-3383, Fax: (734) 936-0374. Correo electronico:homlay@umich.edu

Expansion de la cavidad: Razones y tecnica

ABSTRACTO: Las consecuencias de la exodoncia incluye la reabsorcion alveolar delhueso y finalmente la atrofia del hueso basal de las crestas/lugares edentulosos. Lareabsorcion de la cresta ocurre rapidamente luego de la extraccion del diente y reducesignificativamente la posibilidad de colocar implantes sin procedimientos de injertos. Elobjetivo de este trabajo es describir las razones de los procedimientos de expansion de lacresta alveolar para preservar o reducir la perdida del volumen de la cresta edentulosa.Debido a que la meta de estos metodos es preservar hueso, la exodoncia debera realizarsepara preservar la mayor cantidad posible del proceso alveolar. Luego de cortar las fibrassupra y subcretales usando escalpelos y periotomos, la elevacion del diente frecuent-emente permite la extraccion con un mınimo de dano a la pared de la cavidad. Lascavidades de extraccion no deben estar agudamente infectadas y deben estar completa-mente libres de fragmentos de tejidos suaves antes de intentar cualquier injerto oexpansion. El sangrado de la cavidad que se mezcla con el material de injerto pareceesencial para el exito de este procedimiento. Varios tipos de materiales para el injerto dehueso se han sugerido con este proposito, y algunos han demostrado resultados promet-edores. Cubrir el lugar de extraccion injertado con materiales para vendar heridas, avancede aletas coronales e incluso membranas para barreras, podrıa mejorar la estabilidad de laherida y un proceso de curacion sin problemas. Pruebas clınicas futuras controladas sonnecesarias para determinar el regimen ideal para la expansion de la cavidad.

PALABRAS CLAVES: expansion de la cresta alveolar, preservacion de la cavidad,exodoncia, implantes dentales.

294 ABSTRACT TRANSLATIONS

AUTOR(ES): Hom-Lay Wang, Cirurgiao-Dentista, Mestre em Odontologia*, KoichiKiyonobu, Cirurgiao-Dentista, PhD.** e Ro-drigo F. Neiva, Cirurgiao-Dentista**** Pro-fessor e Diretor de Periodontia Graduada,Depto. de Periodontia/Prevencao/Geriatria,Escola de Odontologia, Universidade deMichigan, Ann Arbor, MI. ** Clınica particu-lar, Toquio, Japao. Bolsista de Pesquisa For-mal Visitante, Depto. de Periodontia/Preven-cao/Geriatria, Escola de Odontologia,Universidade de Michigan, Ann Arbor, MI.*** Professor Assistente Clınico. Depto. dePeriodontia/Prevencao/Geriatria, Escola deOdontologia, Universidade de Michigan, AnnArbor, MI. Correspondencia para: Hom-LayWang, DDS, MSD, Professor and Director ofGraduate Periodontics, Dept. of Periodontics/Prevention/Geriatrics, University of MichiganSchool of Dentistry, 1011 North UniversityAvenue, Ann Arbor, Michigan 48109-1078,USA. Telefone: (734) 763-3383, Fax: (734)936-0374, E-mail: homlay@umich.edu

Aumento do Alveolo: Fundamento & Tecnica

RESUMO: As consequencias da exodontia incluem reabsorcao ossea alveolar e posteri-ormente atrofia ate o osso basal do(s) local/rebordos desdentados. A reabsorcao dosrebordos prossegue rapidamente apos a extracao do dente e reduz significativamente apossibilidade de colocar implantes sem procedimentos de enxerto. Os objetivos destepaper sao descrever o fundamento por tras dos procedimentos de aumento do rebordoalveolar com vistas a preservar ou minimizar a perda de volume do rebordo desdentado.Ja que o objetivo destas abordagens e preservar o osso, a exodontia deve ser realizada parapreservar o maximo de processo alveolar possıvel. Apos o rompimento do encaixe fibrososupra e subcrista usando-se bisturis e periotomos, a elevacao do dente frequentementepermite a extracao com dano mınimo a parede do alveolo. Os alveolos de extracao naodevem estar agudamente infectados e estar completamente isentos de quaisquer fragmen-tos de tecido mole antes que qualquer enxerto ou aumento seja tentado. O sangramento doalveolo que se mistura com o material de enxerto parece essencial para o sucesso desteprocedimento. Varios tipos de materiais de enxerto osseo foram sugeridos para esteproposito, e alguns mostraram resultados promissores. A cobertura do local de extracaoenxertado com materiais de bandagem de feridas, avanco do retalho coronal ou mesmomembranas protetoras, podem aumentar a estabilidade da ferida e um processo de curatranquilo. Futuros testes clınicos controlados sao necessarios para determinar o regimeideal para o aumento do alveolo.

PALAVRAS-CHAVE: aumento de rebordo alveolar, preservacao do alveolo, exodontia,implantes dentarios.

IMPLANT DENTISTRY / VOLUME 13, NUMBER 3 2004 295

296 ABSTRACT TRANSLATIONS