Mandibular overdentures retained by one or two implants: a randomized clinical trial

Abstract

Mandibular overdentures retained by implants have been presented as a treatment option for edentulous patients in order to improve the retention and stability of their lower dentures and also to improve the masticatory performance, with positive effect on the quality of life of these patients. However, the evidences are not conclusive about the efficacy of this treatment using a single implant if compared to overdentures retained by two implants. Objectives: To evaluate and to compare aspects related to treatment with overdentures retained by one or two implants according to the following outcomes: 1 - Quality of life; 2 - patients' satisfaction with their prostheses; 3 - Masticatory performance and 4 - Mandibular movements and the maxillary complete denture movements during chewing; 5 - Marginal bone loss; 6 - Probing depth, bleeding index and plaque index. Methodology: Edentulous patients will receive one set of new complete dentures and after the adaptation period, the patients were randomly divided in two groups and then underwent to placement of one (GI) or two (GII) implants in the anterior mandible. After four months, o'rings abutments will be installed on the implants and the attachments will be connected into the lower denture. The quality of life related to oral health and satisfaction with the prostheses, masticatory performance, mandibular movements and the maxillary complete denture movements during chewing will be evaluated in the following periods: before surgery, 3, 6 and 12 months after activation of the implants. The marginal bone loss also will be evaluated in two periods: the time of activation of the implants and after one year. In addition, clinical examination (probing depth, bleeding index and plaque index) will be performed at different periods: one week, one month and one year after the activation of the implants. The results for each of the variables will be analyzed statistically with a significance level of 5%, by means of the IBM SPSS Statistics, (version 19.0), using appropriate test according to the type of the variable and the adherence of the data to normality. (AU)