Related Experiment Video
Updated: Sep 13, 2025
A Postoperative Evaluation Guideline for Computer-Assisted Reconstruction of the Mandible
Published on: January 28, 2020
Three-year marginal bone loss associated with platform-switched versus platform-matched connections and Morse taper
Dione Gonçalves Pinto1, Aloizio Filgueiras2, Leandro Marques de Resende3
1Doctoral student, Center for Oral Rehabilitation and Imaging, School of Dentistry, Federal University of Juiz de Fora (UFJF), Juiz de Fora, MG, Brazil; and Professor, Estácio Juiz de Fora University Center, Juiz de Fora, MG, Brazil.
Statement Of Problem:
Whether the reduced peri-implant bone loss associated with platform-switched (PS) connections compared with platform-matched (PM) connections is consistent across different implant types remains unclear. Comparative clinical evidence is limited, highlighting the need for studies evaluating the interaction between connection design and implant type.
Purpose:
The purpose of this split-mouth randomized clinical trial was to evaluate the influence of the interaction between connection design and connection type on vertical and horizontal marginal bone loss (vMBL and hMBL) associated with implant-supported prostheses in the posterior mandible after 3 years of follow-up.
Material And Methods:
Fourteen participants received 64 implants in the premolar and molar regions. Each side of the mouth received 2 implants-1 Morse taper (MT) and 1 external hexagon (EH)-with only 1 connection design, PS or PM, thus forming combinations MT+PS, MT+PM, EH+PS, and EH+PM. While each connection design was assigned to 1 side of the mouth, each implant type was assigned to 1 position on the hemiarch, either molar or premolar. Standardized digital periapical radiographs were obtained by using an acrylic resin device customized for each participant, and MBL was assessed immediately, at 3 months, and at 3 years after prosthesis installation. Three-way ANOVA for repeated measures and the Tukey HSD test were used to analyze vMBL, while the Mann-Whitney and Friedman tests were used for hMBL (α=.05).
Results:
vMBL was significantly higher for EH+PS than for MT+PS (P<.05) and higher for MT+PM than for MT+PS (P<.05). hMBL for MT+PS increased significantly over time (P=.009).
Conclusions:
The MT+PS combination outperformed the EH+PS combination in terms of vMBL. Additionally, the PM connection design was ineffective in protecting the MT connection type against vMBL, and the hMBL associated with the MT+PS combination increased over time.
