A LONG-TERM RETROSPECTIVE STUDY OF TWO DIFFERENT IMPLANT SURFACE PLACED AFTER RECONSTRUCTION OF THE SEVERELY RESORBED MAXILLA USING LE FORT I OSTEOTOMY AND INTERPOSITIONAL BONE GRAFT

Purpose: In this retrospective study, the long-term survival and success rates of implants with 2 different surfaces placed in extremely atrophic maxillae augmented with Le Fort I osteotomy and interpositional bone grafts were assessed. Materials and Methods: In 12 consecutive patients (7 female, 5 male; average age, 55 years; age range, 47 to 63 years), the resorbed maxilla was reconstructed using Le Fort I osteotomy in combination with interpositional iliac bone grafts. After 5 to 6 months, machined or titanium plasma-sprayed implants were inserted. The patients were followed clinically and radiographically for 6 to 12 years (mean 102 ± 24.42 months) after prosthetic loading. Implant outcome in terms of survival and success using Albrektsson’s criteria was analyzed. Results: In all cases, the bone-grafting procedures allowed implant placement. Of the 104 implants placed (53 machined and 51 titanium plasma-sprayed), 11 failed, resulting in an overall cumulative survival rate of 89.4%. When the success rate was calculated using the defined criteria, the cumulative success rate was 67.3%. The respective survival and success rates were 86.8% and 66.0% for the machined implants and 92.2% and 68.7% for the titanium plasma-sprayed implants. The mean marginal bone resorption was 2.91 ± 0.77 mm (range, 0.6 to 4.9 mm) around machined implants and 2.72 ± 0.84 mm (range, 0.7 to 5.3 mm) around titanium plasma-sprayed implants. No significant differences in survival, success rate, or marginal bone resorption were found between the 2 implant groups. Conclusions: Le Fort I osteotomy combined with bone grafts and delayed implant placement gave predictable long-term results. There was a distinct relationship between implant survival and the long-term success rate. The implant surface had no significant effect on the survival, success rate, or marginal bone resorption. Int J Oral Maxillofac Implants 2008;23:911–918 Key words: alveolar bone augmentation, atrophic maxilla, autogenous bone graft, dental implants, follow-up study, Le Fort I osteotom

A LONG-TERM RETROSPECTIVE STUDY OF TWO DIFFERENT IMPLANT SURFACE PLACED AFTER RECONSTRUCTION OF THE SEVERELY RESORBED MAXILLA USING LE FORT I OSTEOTOMY AND INTERPOSITIONAL BONE GRAFT

Purpose: In this retrospective study, the long-term survival and success rates of implants with 2 different surfaces placed in extremely atrophic maxillae augmented with Le Fort I osteotomy and interpositional bone grafts were assessed. Materials and Methods: In 12 consecutive patients (7 female, 5 male; average age, 55 years; age range, 47 to 63 years), the resorbed maxilla was reconstructed using Le Fort I osteotomy in combination with interpositional iliac bone grafts. After 5 to 6 months, machined or titanium plasma-sprayed implants were inserted. The patients were followed clinically and radiographically for 6 to 12 years (mean 102 \ub1 24.42 months) after prosthetic loading. Implant outcome in terms of survival and success using Albrektsson\u2019s criteria was analyzed. Results: In all cases, the bone-grafting procedures allowed implant placement. Of the 104 implants placed (53 machined and 51 titanium plasma-sprayed), 11 failed, resulting in an overall cumulative survival rate of 89.4%. When the success rate was calculated using the defined criteria, the cumulative success rate was 67.3%. The respective survival and success rates were 86.8% and 66.0% for the machined implants and 92.2% and 68.7% for the titanium plasma-sprayed implants. The mean marginal bone resorption was 2.91 \ub1 0.77 mm (range, 0.6 to 4.9 mm) around machined implants and 2.72 \ub1 0.84 mm (range, 0.7 to 5.3 mm) around titanium plasma-sprayed implants. No significant differences in survival, success rate, or marginal bone resorption were found between the 2 implant groups. Conclusions: Le Fort I osteotomy combined with bone grafts and delayed implant placement gave predictable long-term results. There was a distinct relationship between implant survival and the long-term success rate. The implant surface had no significant effect on the survival, success rate, or marginal bone resorption. Int J Oral Maxillofac Implants 2008;23:911\u2013918 Key words: alveolar bone augmentation, atrophic maxilla, autogenous bone graft, dental implants, follow-up study, Le Fort I osteotom

ALVEOLAR DISTRACTION OSTEOGENESIS FOR BONE AUGMENTATION OF SEVERELY ATROPHIC RIDGES IN 10 CONSECUTIVE CASES: A HISTOLOGIC AND HISTOMORPHOMETRIC STUDY

Background: This study analyzed bone healing in surgically osteodistracted maxillary and mandibular ridges histologically and histomorphometrically at two different times to determine the best time to insert dental implants. Methods: Ten consecutive patients with severe maxillary (two patients) or mandibular (eight patients) atrophy underwent surgical osteodistraction with an extraosseous distractor. Seven days after the surgery, the distractor was activated at a rate of 1 mm/day until achieving the planned bone lengthening. The distractor was removed after a consolidation period of 70 days. Bone biopsies were obtained at implant insertion: 70 days after the end of distraction on the day of distractor removal in six patients (group A) or 180 days afterwards in four patients (group B). The biopsies were evaluated histologically and histomorphometrically to measure the osteocyte lacunar area (OLA). Results: The histologic and histomorphometrical analysis of the distracted bone 70 days after the end of distraction showed well-organized lamellar bone. At 180 days, the bone was more compact and mature; the mineralization of the matrix was greater; and an increased, but small, amount of marrow space was evident (35% versus 45%). The mean OLA was 80.11 ± 27.59 μm2 in group A and 70.4 ± 33.58 μm2 in group B. The difference between the two biopsy groups was not significant (P = 0.315). Conclusion: The results of this study showed that there was definitely similar bone formation in the distracted area for both healing periods, and placing implants clinically worked in both of these time periods in the limited number of cases observed