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Objective: To evaluate bone remodeling around dental implants inserted into recipient sites prepared using either the piezoelectric or the conventional drilling technique., Material and Methods: Twenty-four male New Zealand white rabbits (4 months, 2.70 kg) received dental implants (3.3 mm diameter and 6 mm length) on the medial surface of the tibia and were divided into 3 groups (n = 8). Group I was euthanized at 7 days; group II, at 14; and group III, at 28 days. Each animal received four implants, two in the right and two in the left tibia (96 implants were installed). Each tibia was operated by the same technique, and there are therefore neighbor's implants installed by different techniques. Histomorphometric parameters were used: the volume occupied by trabecular bone around the implants (BV/TV), media thickness, separation and number of trabeculae around the loops, and the contact area (interface) directly between the bone and implant (BIC)., Results: BV/TV was similar for both techniques (P = 0.291). Reduction in trabecular thickness was observed for both techniques (P < 0.05), but then returned to prior levels, with no significant difference between techniques (P = 0.217). Trabecular number increased from day 7 to day 14 (P < 0.001) and remained constant afterward for both techniques. No difference in BIC was observed between techniques on day 28 (P = 0.961)., Conclusions: Piezoelectric osteotomy allowed bone formation for osseointegration of titanium implants, was not associated with bone necrosis, and provided results similar to those of the conventional technique. The piezoelectric technique can be considered a viable alternative in dental implantology., (© 2013 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)

Objectives: This study evaluated the stability of implants installed simultaneously and in a delayed manner in fresh frozen onlay allografts in the tibiae of rabbits., Material and Methods: Analyses of the resonance frequency (ISQ) and removal torque were performed. The calvarium of three rabbits was used as donor site. Ten New Zealand female rabbits received four allografts of the same dimensions, two in each tibia. The tibiae were randomly allocated into the following two groups: Group 1, the tibiae that received implants after 84 days of healing, and Group 2, those who received the implants simultaneously with the grafts. Both groups were followed for 126 days. Proximal implants in each group were evaluated by resonance frequency (ISQ) on days 0 and 126, and the distal ones with removal torque on day 126., Results: In both groups, an increase in the ISQ value of day 0-126 was observed, with a statistically significant difference (Group 1 P = 0.049 and Group 2 P = 0.021). When comparing the resonance frequency at day 0 to day 126, and the gain of stability between these days, no statistically significant difference between groups could be observed. The removal torque showed a statistically significant difference between groups 1 and 2 (P = 0.042)., Conclusion: There was an increase in stability in groups according to the analysis of resonance frequency. Implants installed in a delayed manner in allografts showed higher shear force, according to the removal torque analysis., (© 2012 John Wiley & Sons A/S.)