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The aim of the present retrospective chart review was to determine the relationship between nonvascularized osseous graft remodeling and the three-dimensional (3D) features of grafts and recipient sites, the anatomical recipient regions and different graft sources. 32 iliac crest or chin grafts were onlay-positioned in the mandible or maxilla of 14 patients. CT scans, taken before implant positioning and after 1 year, revealed a mean volume resorption of 35-51%. For iliac crest grafts, the average resorption was 42% when the onlay was positioned in the anterior maxilla and 59% when it was positioned in the posterior mandible. Spearman correlation and 3D interpolation analysis revealed, for both iliac crest groups, a moderate or advanced remodeling pattern depending on 3D features, namely graft thickness and shape, basal bone volume of recipient site, and the basal bone/graft volume ratio of the recipient site. No statistically significant differences were found between the recipient and donor site groups. Retrospective analysis of the data indicates that iliac crest grafts, onlay-positioned on adequate basal bone volume, may register a reduced volume remodeling when shaped thick in the anterior maxilla or rounded and convex, on the external surface, in the posterior mandible.

Purpose: This article discusses a 3-year retrospective survey of implant clinical survival and computerized tomographic analysis of bone remodeling in atrophic alveolar crests reconstructed via various autogenous bone grafting procedures and in similar regions of native bone., Materials and Methods: The retrospective chart review included consecutive edentulous patients with severe alveolar crest atrophy treated between 2000 and 2002 with onlay autogenous bone grafts in the mandible and anterior maxilla (as needed) and implant insertion. Implant recipients were followed for 3 years. Defective areas were reconstructed by bone graft harvested from the chin or iliac crest. Implants in reconstructed areas were divided into two groups according to graft source. Implants in corresponding native areas served as controls. Cumulative survival rate (CSR), survival rate, and confidence interval (CI) were calculated, and linear measurements of bone remodeling around implants were assessed on computerized tomographic scans. Results were compared for statistically significant differences by Wilcoxon signed-rank test with a significance level a = .05., Results: Forty patients were treated with 109 screw-type, root-form, rough-surfaced implants inserted in 48 onlay grafts; 88 implants were placed in native bone. The implant 3-year CSRs were 98.9% (CI 96.7% to 100%) in native bone and 99.1% (CI 97.3% to 100%) in onlay grafts, irrespective of bone source. Mean resorption in the maxilla was 4.6 +/- 0.9 mm buccally and 3.8 +/- 0.8 mm palatally in areas reconstructed with chin grafts, 3.4 +/- 1.7 mm buccally and 2.6 +/- 1.4 mm palatally in areas reconstructed with iliac crest grafts, and 3.2 +/- 1.2 mm buccally and 2.1 +/- 0.9 mm palatally in native areas., Conclusions: Similar implant CSRs were seen in native and grafted sites. Maximal implant CSR was observed in onlay grafts from the chin despite more marked linear bone remodeling in this group as compared to iliac crest grafts or native bone.

Purpose: The present study was a 3-year follow-up evaluation of implant clinical success and radiographic bone remodeling in sinus floors elevated with different autogenous bone-grafting procedures and in similar native bone regions., Materials and Methods: This retrospective chart review examined consecutive edentulous patients with severe jaw atrophy treated between 2000 and 2002 via sinus lift, when needed, and implant insertion. Implants in sinus lift areas were divided into four groups by graft source (iliac crest, chin area) and technique (bone block, particulate). Implants positioned in native areas beneath the sinus floor served as controls. The cumulative success rate (CSR) and success rate (SR) were calculated, and linear measurements of bone remodeling around implants were assessed on computerized tomographic scans. Results were statistically compared with the Wilcoxon signed rank test., Results: Twenty-eight patients were treated in the posterior maxilla via insertion of 70 screw-type, root-form, rough implants in 39 sinus-lifted areas. All surgical procedures were uneventful. Twenty-four implants were positioned in native areas beneath the sinus floor. The implant CSR was 95.8% in native areas (one failure/24 implants), 85% in sinuses lifted with particulate chin bone (three failures/20 implants), and 100% in the other three groups (eight in particulate iliac crest, 20 in chin block, and 22 in iliac crest block). Computerized tomographic scans revealed that bone remodeling around apices caused implants to bulge into the sinuses in both particulate bone graft groups. Crestal remodeling around implant necks was similar for all groups., Conclusions: The use of particulate chin bone grafts in sinus lift procedures does not seem to yield optimal outcomes. Milled iliac crest and chin bone tends to remodel around the implant apices, leading to bulging within the sinuses. Grafting sinuses with either chin or.iliac crest bone blocks yields the highest implant success rates and stable sinus floors.