HEALING AND REMODELING OF CONNECTIVE TISSUE GRAFT AROUND IMPLANTS WITH POOR KERATINIZED MUCOSA.INFLUENCE OF PROVISIONALIZATION TIMING (DELAYED VS IMMEDIATE) USING BOPT ABUTMENTS.A CLINICAL OBSERVATIONAL CONTROLLED PILOT STUDY.

Aim of the study : the aim of the present study was to investigate the most effective timing of the surgical-prosthetic procedure in order to obtain a stable soft tissue augmentation around dental implants using BOPT abutments. Materials and Methods : Overall, 13 patients have been enrolled. A total amount of 21 implants have been placed and they have been alternatively assigned to the case (immediate provisionalization) or control group (delayed provisionalization) on the basis of the waiting list. The clinical criteria adopted for the enrollment in the study were the partial edentulism in which the teeth were lost at least 2 months before the date of implant placement with KM lower than 2 mm or inadequate soft tissues volume for a proper ridge contour. The two parameters evaluated for test and control groups were the apico-coronal migration and the soft tissue gain after grafting procedure. Results : gingival recession: for the control group 10 implants were analyzed between first and second evaluation. The mean difference was - 0.011 ± 0.8 mm (95% CI: - 0.3 to 0.27mm). For the test group 9 implants were analyzed between first and second evaluation. The mean difference was 0.0 ± 0.8mm (95% CI: - 0.35 to 0.37mm). Soft tissue gain: for the control group 8 implants were analyzed at the first evaluation. The mean augmentation was 1.17± 0.55 mm (95% CI: 1.12 to 1.45 mm). For the test group 4 implants were analyzed at the first evaluation. The mean augmentation was 0.82 ± 0.52 mm (95% CI: 0.85 to 0.65 mm). Conclusions : Both the prosthetic-surgical approaches are valid in order to treat limited horizontal defects with the application of connective tissue graft without recurring to costly, invasive and long lasting guided bone regeneration procedures. Considering the lack of available information from the preliminary results it is impossible to assess which is the best therapeutic option. A total amount of 34 implants will be necessary to be able to reject the null hypothesis that the population means of the experimental and control groups are equal with probability (power) 0.8.