Clinical performance of splinted 4.5-mm extra-short implants. A controlled retrospective cohort study.

Abstract

To compare survival, marginal bone loss (MBL) and prosthetic complications of 4.5-mm extra-short implants and longer implants splinted to the same type of implant. A retrospective controlled cohort study was performed. The 4.5-mm extra-short group (study group; SG) included 48 consecutively placed implants that met inclusion criteria. Control group (CG) included 48 implants splinted to them. The same surgical team treated the 39 patients included, and all the implants were restored with a screw retained fixed restoration and intermediate abutments. Immediate and conventionally loaded implants were included. All the implants were in function during the follow-up period (14 ± 3.4 SD and 17 ± 13 SD months for SG and CG). No differences in technical complications were observed between both groups (1 and 2 screw loosening for SG and CG; 2 fractures in provisional prosthesis for SG; p=0.310). Marginal bone stability was similar for SG and CG at mesial level (SG: Mean -0.01 ± 0.28 SD mm Vs CG Mean -0.18 ± 0.72 SD mm; p=0.270) and at distal level (SG: Mean 0.02 ± 0.39 SD mm Vs CG Mean -0.18 ± 0.68 SD mm; p=0.076). The same good clinical performance could be observed for 4.5-mm implants and longer implants under the same prosthesis.