Aim: This study aimed to evaluate biological and prosthetic complications of cantilevered and non-cantilevered fixed hybrid metal acrylic prostheses used for vertical and inclined implants in atrophied mandible.
Materials and Methods: Eight completely edentulous individuals will be classified into 2 groups randomly: 1) Group I (cantilevered prosthesis, n=4): patients received 4 vertical implants parallel to each other's in the interforaminal area and cantilevered metal acrylic prosthesis, 2) Group II (non-cantilevered prosthesis, n=4): patients received 4 implants (2 parallel anterior implants and 2 posterior implants inclined 30odistally) and non-cantilevered metal acrylic prosthesis. Biological and prosthetic complications were measured after one year from prosthesis insertion.
Results: There was no significant difference in implant failure, implant survival, pain, swelling, abscess, fistula formation, peri-implantitis, peri-implant mucositis, bleeding on probing between groups. The non-cantilevered group showed significantly higher pocket depth than the cantilevered group. The cantilevered group showed significantly higher bone loss than the non-cantilevered group. There were no prosthesis fractures, cylinder fracture, abutment fracture, and prosthetic screw fracture occurred in both groups. There was no difference in teeth wear, teeth fracture, and gingival fracture between groups. The cantilevered group showed a significantly higher crown fracture, abutment screw, and prosthetic loosening than the non-cantilevered group.
Conclusion: Both cantilevered and non-cantilevered fixed hybrid metal acrylic prostheses can be used successfully for vertical and inclined implants respectively in atrophied mandible with favorable biologic and prosthetic outcomes after one year.