Purpose: This randomized controlled clinical trial study assessed prosthetic complications and peri-implant vertical bone loss (VBL) of screw retained fixed hybrid prostheses (FHP) and palateless implant retained overdentures by locator (LOD) in patients with edentulous maxillae.
Materials and methods: Sixteen healthy completely edentulous patients were participated in this study. All patients were received four implants in maxillary arch in laterals and premolars areas and two implants in the mandibular canines regions. All patients received single design mandibular implant retained overdenture with locator attachment. According to the design of maxillary prosthesis there were two groups: 1) Group I (FHP, n=8): 2) Group II (LOD, n=8). Prosthetic complications were estimated after one year from prosthesis insertion. Digital radiography was used for VBL assessment around maxillary implants at insertion, 6 and 12 months. Statistical analysis was done by Chi-square test and Mann-Whitney.
Result: Regarding prosthetic complication: There was no statistically significance difference between FHP (Group I) and LOD (Group II) concerning the total frequency of prosthetic complications at prosthesis level (P=0.33) and implant level (P=0.21) for both types of restorations. As regards VBL: FHP (Group I) exhibited significantly higher VBL than LOD (Group II) at T12 (P=.031*).
Conclusion: Within the limits of this short term clinical trial, both FHP and LOD can be used successfully for rehabilitation of edentulous maxilla opposing mandibular implant overdenture with insignificant difference regard total frequency of prosthetic complications at prosthesis and implant level after one year. However, LOD was advantageous concerning reduced peri-implants VBL compared to the FHP.