Purpose: To performed a histomorphometric and radiological study to evaluate the effects of alendronate sodium administered locally in mandibular bone defects created in rabbits. Methods: Two circular defects 5 mm in diameter were created bilaterally in the mandibular corpus of 20 New Zealand rabbits (i.e., four defects per animal). Each defect received one of four treatments: no treatment (EC group), alendronate irrigation (AL group), autogenous bone grafting (AG group), or alendronate irrigation with autogenous bone grafting (AL+AG group). Histomorphometric and radiological assessments were conducted at 4 and 8 weeks after surgery. Results: Between-group comparisons of the new bone area, the value of the AL+AG group was significantly lower thanthe remaining three groups at 4 weeks postoperatively. In all groups, the new bone area was significantly larger at 8 weeks than at 4 weeks. The residual graft area at 4 and 8 weeks was significantly higher in the AL+AG group than in the AG group, although it was significantly smaller at 8 weeks than at 4 weeks in both these groups. Conclusion: The use of alendronate sodium in conjunction with autogenous bone grafting improves the osteoconductive properties of the graft, enhances graft retention in the defect, and improves ossification.

The aim of this study is to compare the bone healing in the distraction gap following the osteotomy performed with piezoelectric and conventional devices for the distraction osteogenesis in the rabbit mandibles. Twelve rabbits were randomly divided into 2 groups; 6 for piezoelectric device and 6 for rotary instruments. After 3 days of latency period, distraction was started at a rate of 1 mm per day for 10 days. All the animals were sacrificed after 4 weeks of consolidation phase for histological and histomorphological evaluation. Histological evaluation revealed thick trabecular bone formation in all of the specimens. Inflammation scores were chronic minimal. The mean percentages of the bone area in distraction gap are 62% in group P and 57% in group R. However, the difference between 2 groups was not statistically significant (P > 0.05). Our results revealed a slight increase in bone formation in the distraction gap in piezo-osteotomy groups histologically though not statistically supported. However, there is still a need for more histological studies with larger sample sizes evaluating the bone structure following piezo-osteotomies.

ObjectiveThe aim of this study was to evaluate the effect of teriparatide (PTH 1-34, rhPTH) on a rabbit defect model with local xenogen grafts histomorphometrically and radiologically.MethodsFor this purpose, two 10 mm diameter critical-size defects were created in the calvaria of 16 rabbits. In the control group, the defect area was filled with a xenogen graft, while in the teriparatide group (PTH 1-34), a xenogen graft combination with 20 mcg teriparatide was used. For both 4 – week and 8 – week study groups, new bone, residual graft, and soft tissue areas were evaluated as well as bone volume histomorphometrically and radiologically.ResultsHistomorphometrically, there was a significant difference in new bone area values at the 8th week (p < 0.05), but there was no significant difference between the 4 – week values (p > 0.05). There was no statistically significant difference between the groups at both 4 and 8 weeks (p > 0.05). In the radiologically measured total bone volume values, PTH1-34 group values were found to be significantly higher for both 4 – and 8 – weeks values compared to the control groups (p < 0.05).ConclusionIn this study, rhPTH, which is used locally in defect areas to be repaired with bone grafts, increases both new bone volume and total bone volume.

Background Risedronate is a bisphosphonate with poor oral absorption. An extremely hydrophilic molecule that has a high affinity for bone, risedronate also inhibits the farnesyl diphosphate synthase enzyme, inhibiting osteoclastic activity and reducing bone turnover and resorption. Autogenous bone grafts contain osteogenic cells and osteoinductive factors that are essential for bone regeneration and are therefore considered the gold standard. Thus, this study aimed to investigate the impact of local risedronate administered with autogenous bone grafts on the healing of defects in rabbit skulls using histological, histomorphometric, immunohistochemical, and three-dimensional radiological methods. Methods Two 10-mm-diameter critical-size defects were created in 16 rabbits and filled with autogenous bone graft and autogenous bone graft + 5 mg risedronate in the control (C) and risedronate (RIS) groups, respectively. Residual graft, new bone, soft tissue areas, and bone volume were evaluated in the 4- and 8-week study groups. Results There were no statistically significant differences in bone graft, new bone, or soft tissue area between the groups at 4 weeks (p > 0.05). At 8 weeks, the new bone area was significantly higher in the RIS group than in the C group (p < 0.05). The h scores obtained from sialoprotein and osteopontin did not differ significantly between the groups (p > 0.05). The radiologically measured total bone volume was significantly higher in the RIS group than in the C group at both time points (p < 0.05). Conclusions In this study, risedronate enhanced the osteoconductive properties of autogenous bone grafts and rapidly created better-quality bone. This could improve future patient outcomes.