Resultados clínicos da reabilitação com implantes dentais unitários: cinco anos de acompanhamento

Abstract

Purpose: The aim of this retrospective study was to evaluate the long-term survival rates and the frequency of complications associated with single implants and their implant-prosthodontic reconstructions. Materials and Methods: A retrospective cohort study was performed in patients that received dental implants placed between 1997 and 2007. The cohort was composed of patients who had a single-tooth implant restored with a cementless or screwed restoration with more than two years in function. The cumulative implant survival rates and peri-implant conditions (marginal bone loss, pocket depth, plaque index, gingival and bleeding index) as well as the prosthodontic maintenance requirements were evaluated. Descriptive statistics, chi-square test and regression models, were used. Results: In all, 73 implants were placed in 44 patients (32 women, 12 men; mean age 48 years). All implants were available for a follow-up evaluation after 2 to 13 years (mean follow-up, 60 months). The overall cumulative 5-year survival rates for implants were 95.9% and the most of prostheses (98.6%) were functional throughout the observation period. The overall frequency of complications was 29.6% (4.3% inflammatory, 22.5% prosthetic, 2.8% operative). The average peri-implant marginal bone reabsorption value was 1.8mm. Peri-implant soft tissue conditions such as plaque, bleeding, and pocket depth were also satisfactory. However, the presence of inflammation was associated with pocket depth (P=0.000) and gingival keratinized mucosa (P=0.031). Abutment screw loosening (21%) for single-tooth restorations were the most frequent prosthodontic maintenance needs. However, all loose abutment screws occurred in screw-retained prostheses with titanium screws and 92.9% of the prostheses had UCLA type abutment. Conclusion: The implants and the associated prosthetic constructions used in this study showed excellent survival rates. However, there was high frequency of prosthetic complications that were associated with titanium screws and UCLA cast abutments.