Effect of abutment connection type on crestal bone resorption around implants

Purpose: To test the hypothesis that the type of implant abutment connection configurations may influence the stresses and strains induced in the peri-implant area and affect crestal bone resorption around implants.
Materials and Methods: Sixty implants were inserted in forty two male patients (mean age 44 years old) and randomly divided into two groups according to internal hexagon (Legacy™
2, Implant Direct, USA) and conical hybrid connection (AnyRidge; MEGAGEN, Seoul, Korea). Abutments were connected and restoration delivered four months after implants placement. Each case was evaluated radiographically and linear measurements of bone resorption were made from the implant’s platform to the first point of bone-to-implant contact at baseline (time of restoration delivery), 6,12, 24 and 36 months later. Data were collected, tabulated and statistically analyzed with repeated measures two way ANOVA test.
Results: No statistical significant differences were found between the tested groups
(P ≥ 0.05). Peri-implant bone changes demonstrated mean bone loss of (1.17 ± 0.58) for Group (1) and (1.12±0.53) for Group (2) after three years of insertion.
Conclusions: Despite the limitations of this controlled clinical trial and although no statistical significant differences were found, conical hybrid implant abutment connection showed less crestal bone resorption around implants than internal hexagon implant in short term evaluation.
Keywords: implant abutment, internal connection, conical hybrid, crestal bone resorption.
This study was conducted at faculty of dentistry, Tanta University, Egypt after the approval of the Ethics committee of the faculty.