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implants - international magazine of oral implantology International Edition

then inevitable. The wound healing was subsequently uneventful,buttherewasnotenoughboneforinsertion of implants. A second augmentation procedure was then performed in only two cases. The patients with temporary paraesthesia by the suture removal always had control appointments until the healing of their nervedysfunction(Tab.7). Bone resorption was easily visible on removing the osteosynthesis screws since the heads of the screws were always 1 to 2 mm above the grafted bone. On re- opening,theshapeofthegraftedblockwasrarelyvisi- ble in most of the cases. Of the 104 bone reconstruc- tions,19(18.2%)requiredsimultaneousaugmentation atthetimeofdentalimplantplacement. The average healing period after bone harvesting was 125.8 days or 4.49 months, ranged from 91–276±66.23 days. 155 dental implants were placed, 39inthemaxillaand116inthemandible.Alltheseim- plants were placed using the CoDiagnostiX® (IVS Solu- tions AG) program for guided surgery. All the implants were integrated at the abutment connection. To date (meanofsixmonthsafterprostheticloading)alltheim- plants were successful, according to the Albrektsson criteria.62 In eight of the cases (7.6%), implant installa- tionwasnotpossibleduetoinsufficientboneafteraug- mentationprocedures.Despitethecomplications,asig- nificantlyhigherlossofbonegraftswasnotfound.Af- ter the prosthetic rehabilitation, the oral function was completelyre-establishedinallpatients. _Discussion Theuseofendosseousimplantsmaybelimitedbyin- sufficientqualityandquantityofavailablebone.Several graftingprocedureshavebeendescribedtocreatesuf- ficient volume of bone for implant placement.33 Auto- genousgraftsstillremainthe“goldstandard”inrecon- structive surgeries due to their osteoinductive, osteo- conductive,andosteogenicpotential,essentialforbone morphogenesis.34-35 SerraeSilvaetal.concludethatau- togenous bone grafts are the best option compared withallograftsandxenograftsduetoitspropertiesand constitute a viable form of treatment for patients with alveolar bone loss.36 The placement of implants into healed bone grafts as a secondary procedure is similar totheiruseinjawsthathavenotbeengrafted.37 Severalstudieshavereportedonharvestingofgrafts from the retromolar region.13, 20, 22, 24, 26, 28 However, the numberofcomplicationsisdiscordantwhenthediffer- enttrialsarecompared.Thisseemstobebecausenone ofthestudiesisprospectiveandbasedonobjectivetests for the function of inferior alveolar and lingual nerves. Advantagesofretromolarbonegraftsaretheuseoflo- calanaesthesiainsteadofgeneralansesthesia,noneed tostayinhospitalpostoperatively,lessmorbidityatthe donor sites, and lower costs.38, 39 A disadvantage is the smallvolumesofboneoffered. Performingridgeaugmentationandimplantplace- ment as two-stage surgery is still said to be more suc- cessful than the single-stage procedure.31, 40 A healing period for mandibular grafts of four months has been recommended.5, 13, 31 There is experimental evidence that grafts from membranous bone show less resorp- tion than endochondral bone due to early revascular- ization, better potential for incorporation in the max- illofacial region because of a biochemical similarity in theprotocollagen,andtheinductivecapacityisgreater because of a higher concentration of bone morpho- geneticproteinsandgrowthfactors.Theearlyrevascu- larization seems to explain the good maintenance of volumeoftheretromolargraft.41 However,amajordis- advantage of retromolar grafts remains. Only a con- finedamountofbonecanbeharvestedfromthisdonor I research Table 2_Review of the literature on harvesting of retromolar bone grafts. Fig. 3_Association between jaw and complications of the recipient site. 08 I implants4_2013 Autors No.of patients Reported complications Girdler & Hosseini 1992 12 Temporary lingual paraesthesia Raghoebar et al.1996 7 none VonArx et al.1996 4 none Misch 1997 19 Incision dehiscence Schlegel et al.1998 5 none VonArx et al.1998 13 Hypoaesthesia n.V3, massive postop.bleeding Cordaro et al.2002 15 Bone resorption Clavero 2003 24 Hypoaesthesia n.V3 Schwartz-Arad 2005 10 Graft exposure, Hypoaesthesia n.V3 Schwartz-Arad 2005 18 Incision dehiscence, Graft exposure, Hypoaesthesia n.V3