The aim of the present study was to evaluate the effect of local melatonin application during surgery on bone implant connection (BIC) in rabbit tibiae. Six 0.8- to 1-year-old male New Zealand rabbits were divided into 3 groups: (1) a control group (CG) in which rabbits were not treated with additive materials and only implant integration was executed; (2) a melatonin dose 1 (MLT D-1) group in which rabbits were treated with 1.2 mg of melatonin locally before implant placement into the rabbits' tibiae; and (3) a melatonin dose 2 (MLT D-2) group in which rabbits were treated with 3 mg melatonin locally before implant placement into the rabbits' tibiae. Four weeks after the procedure, the rabbits were euthanized; their tibiae were dissected from muscles and soft tissues, fixed with formaldehyde, and later embedded in methacrylate. Histologic and histomorphometric analyses were then performed under light microscopy. Following this, BIC was detected histomorphometrically, and P < .05 was considered statistically significant. Results showed that the highest BIC percentage was detected in MLT D-2, with a mean value of 39.46% ± 0.78, as compared with a mean value of 33.89% ± 0.92 in group MLT D-1 and 27.42% ± 0.89 in CG. Similarly, the mean BIC percentage of the MLT D-2 group was the highest among the three, with the mean BIC percentage of the MLT D-1 still registering as higher than CG. Within the limitations of this rabbit study, it appears that local melatonin application during implant surgery may improve BIC.

ObjectivesIn this study, we investigated whether a high-fat diet (HFD) affected the bone implant connection (BIC) in peri-implant bone.Materials and MethodsFour male rabbits were used in this study. Dental implant surgery was introduced into each tibia, and four implants were integrated into each animal. In both the normal diet (ND) group (n=2) and HFD group (n=2), 8 implants were integrated, for a total of 16 integrated implants. The animals continued with their respective diets for 12 weeks post-surgery. Afterward, the rabbits were sacrificed, and the BIC was assessed histomorphometrically.ResultsHistologic and histomorphometric analyses demonstrated that BIC was not impaired in the HFD group compared to the ND group.ConclusionWithin the limitations of this study, we found that HFD did not decrease the BIC in rabbit tibias.

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In this study, the aim was to compare the relative efficacy of systemic and local zoledronic acid (ZA) on a hydroxyapatite (HA) bone graft in a rat critical-size calvarial bone defect. In total, 84 female rats were divided into four groups: Empty control (EC) group with no treatment applied; HA group, in which only HA bone graft material was used in the calvarium; and HA plus local ZA (HA+LZA) and HA plus systemic ZA (HA+SZA) groups, in which animals received ZA locally or systemically, respectively, with HA bone graft material in the calvarium. A 5-mm standardised critical-size calvarial bone defect was created with a standard trephine drill and the respective treatment was applied. Rats were sacrificed 7, 14 and 28 days later. The numbers of osteoclasts and osteoblasts, and degree of bone formation were evaluated histopathologically and histomorphometrically. Statistically significant differences were detected between the HA, HA+LZA and HA+SZA groups and the EC group for new bone formation (P<0.05). Osteoblast numbers in the HA+LZA and HA+SZA groups were significantly higher compared with those in the EC and HA groups (P<0.05). No statistically significant difference was detected between the HA+LZA and HA+SZA groups in new bone formation or osteoblast number (P>0.05). Bone formation was significantly higher in the HA group than in the EC group (P<0.05). The numbers of osteoclasts in the HA+LZA and HA+SZA groups were significantly higher than those in the groups EC and HA (P<0.05); however, there was no significant difference between groups HA+LZA and HA+SZA (P>0.05). Within the limitations of this study, systemic or local administration of ZA enhanced new bone formation with a HA bone graft in a rat critical-size calvarial defect model.

The aim of this study was to evaluate the effects on new bone formation of autogenous blood alone or in combination with zoledronic acid (ZA), a β-tricalcium phosphate (β-TCP) graft or ZA plus a β-TCP graft placed under titanium barriers. For this purpose, eight adult male New Zealand white rabbits were used in the study, each with four titanium barriers fixed around four sets of nine holes drilled in the calvarial bones. The study included four groups, each containing 2 rabbits. In the autogenous blood (AB group), only autogeneous blood was placed under the titanium barriers. The three experimental groups were the AB+ZA group, with autogenous blood plus ZA, the AB+β-TCP group, with autogeneous blood plus a β-TCP graft, and the AB+β-TCP+ZA group, with autogeneous blood plus a β-TCP graft and ZA mixture under the titanium barriers. The animals were sacrificed after 3 months. The amounts of new bone formation identified histomorphometrically were found to be higher after 3 months than at the time of surgery in all groups. The differences between the groups were examined with histomorphometric analysis, and statistically significant differences were identified at the end of the 3 months. The bone formation rate in the AB+β-TCP+ZA group was determined to be significantly higher than that in the other groups (P<0.05). In the AB+ZA and AB+β-TCP groups, the bone formation rate was determined to be significantly higher than that in the AB group (P<0.05). No statistically significant difference in bone formation rate was observed between the AB+β-TCP and AB+ZA groups. Local ZA used with autogeneous blood and/or graft material appears to be a more effective method than the use of autogeneous blood or graft alone in bone augmentation executed with a titanium barrier.