A 3-year prospective cohort study on mandibular anterior cantilever restorations associated with screw-retained implant-supported prosthesis: An in vivo study

AIM: The aim of this study is to evaluate the survival of single implant supported cantilever prosthesis (ISCP) replacing missing two adjacent natural teeth in the anterior mandible. SETTINGS AND DESIGN: In vivo - Prospective cohort study. MATERIALS AND METHODS: Thirty patients with missing both mandibular central incisors were selected. A single implant was used to replace the missing teeth and restored with cantilever screw-retained prosthesis. Twenty-two patients were followed for 3 years for the implant and prosthetic success. STATISTICAL ANALYSIS USED: Weibull test for survival probability. RESULTS: Survival probability of the ISCP for the first 100 days was found to be 97.55%, for 200 days, it was 71.4%, for 250 days, it was 46%, and for 365 days, it was 3.9%, i.e., 20 prosthesis had screw loosening after prosthetic loading. However, it increased to 95.2% at the end of 3 years. CONCLUSION: Screw-retained ISCP developed early technical complications. After prosthetic loading, the survival probability of the screw-retained ISCP was very low (3.9%) at one year, which increased to 95.2% after retightening and retorquing of the abutment screw, porcelain repair and conformation of the tongue to the prosthesis. The most common prosthetic failure was screw loosening (81%), followed by porcelain fracture (14.3%), and implant survival of 95% at the end of three years.