Survival of Dental Implants Placed Pre-Radiotherapy Versus Post-Radiotherapy in Native Bone: A Systematic Review.

PURPOSE: To systematically measure the survival rate of implants placed pre- and post-radiotherapy. MATERIALS AND METHODS: After performing a systematic literature exploration of 10 databases, observational and quasi-experimental studies and case series estimating the survival of dental implants in patients with head and neck cancer placed before, after, and without radiotherapy were included, with no limit on language or year of publication. The Joanna Briggs Institute Critical Appraisal was used to assess the risk of bias in eligible studies. RESULTS: During the first screening phase, 3,445 studies were found, among which 16 met the inclusion criteria. The median follow-up period was 60 months (range: 1 to 168 months). Seven (43.7%) articles had a moderate risk of bias, four (25%) had a high risk of bias, and five (31.3%) had a low risk of bias. The survival rate for post-radiotherapy, pre-radiotherapy, and without-radiotherapy implants was 80% to 100%, 89.4% to 97%, and 92.2% to 100%, respectively. CONCLUSION: Despite the alterations caused by ionizing radiation in peri-implant tissues, dental implants placed pre- and post-radiotherapy had high survival rates, similar to those placed without radiotherapy, which helps improve the condition of life of patients with head and neck cancer.

Implant Osseointegration in Grafted Autogenous Bone Blocks Fixed with Screws and Cyanoacrylate-Based Adhesive: Histomorphometric and Micro-CT Analyses.

PURPOSE: To evaluate implant osseointegration in grafted autogenous bone blocks fixed with cyanoacrylate-based adhesive and screws. Also, grafted bone fixed either with an adhesive or screw was evaluated. MATERIALS AND METHODS: Two surgical defects in the parietal region of rabbits (n = 12) were performed in each animal. Autogenous bone blocks obtained were fixed anteriorly with a screw or cyanoacrylate-based adhesive. After 30 and 45 days of grafting procedures, implants were placed in bone blocks. Histomorphometric and microcomputed tomography (micro-CT) analyses of the implant area were performed at 30 days after implant surgery in the screw (n = 6) and adhesive (n = 6) groups. Histomorphometric analyses of bone-grafted areas were performed at 60 and 75 days in the screw (n = 6) and adhesive (n = 6) groups. Histomorphometric evaluations were carried out in implant and grafted bone areas. The micro-CT parameters evaluated were bone-to-implant contact, bone area fraction occupancy, bone volume fraction, trabecular thickness, trabecular separation, and trabecular number. RESULTS: No differences were observed in the micro-CT parameters for the screw and adhesive groups in all experimental periods. However, an increased quantity of immature bone volume was observed on the adhesive group in the grafted area after 75 days. The grafted area in the screw group (75 days) presented a decrease in the volume density of the immature bone compared with the screw group (60 days). There were no differences in both groups and experimental periods in soft tissue in the grafted area. CONCLUSION: No differences were observed in the osseointegration of implants placed in grafted autogenous bone blocks fixed with cyanoacrylate-based adhesive and screws. Therefore, osseointegration in autogenous bone fixed with cyanoacrylate-based adhesive is viable.