Impact of Platform Switched Implants on Marginal Bone Level in Mandibular Overdentures: A Six-Year Follow-Up Longitudinal Study.

Purpose: To evaluate the impact of the platform-switched implant on marginal bone loss (MBL) and the probing pocket depth (PPD) in patients wearing mandibular overdenture. Patients and Methods: This longitudinal study included 40 completely edentulous patients aged 51– 64 years. All patients received complete dentures and were distributed into two groups randomly; 20 patients each. The first group GI received two platform switched implants; however, the 2nd group GII received two platform matched implants (3.6 × 11.5 mm) in the canine region of the mandible. The radiographic evaluations were carried out every year for six years, whereas probing pocket depth was evaluated every six months for 72 months for both groups. The data were analyzed by repeated ANOVA, Friedman's, and Student's t-test. Results: This study included 36 patients; 56 ± 3.6 years was the mean age; 17 females (47%) and 19 males (53%) completed the study. Statistically significant differences were observed in MBL and PPD in each of GI and GII after 6 years, p ≤ 0.05. Between GI and GII after 6 years, a statistically insignificant difference was detected in MBL or PPD, p ≥ 0.05, except in PPD at loading, 2 and 6 years, p ≤ 0.05. Conclusion: Time positively affected MBL and PPD in platform switched and matched implants retained mandibular overdentures. Platform switching influences probing pocket depth in implants retained mandibular overdentures. [ABSTRACT FROM AUTHOR]