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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. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Aim: To discuss important topics regarding the dental procedures performed in patients before, during and after the radiotherapy treatment. The biological effects of ionizing radiation on bone tissue focusing on clinical care will be described. The invasive and not invasive procedures after radiotherapy treatment in the head and neck region will be addressed using scientific evidences to determine the appropriate moment for tooth extractions, periodontal management, and preventive procedures for osteoradionecrosis. Methods: Thirty-three studies including original studies and reviews were selected in MEDLINE database (PubMed). No year of publication restriction was applied. Language was restricted to the English, and the following Medical Subject Heading terms were used: radiotherapy, osteoradionecrosis, dental management. Studies of osteoradionecrosis involving clinical management of irradiated patients, with an emphasis on updated guidelines and protocols were selected. Results: Care in dental procedures were related about restorative treatment, endodontic treatment, rehabilitation for edentulous regions using prostheses and implants and periodontal procedures before, during and after RTX treatment. Conclusions: The dental procedures should and can be performed before, during but also after radiotherapy. However, the clinical procedures should be less invasive as possible. A maintenance plan that reduces the necessity for major and more invasive treatments after radiotherapy is recommended. [ABSTRACT FROM AUTHOR]

Mononuclear cells play an important role in the modulation of healing. The characteristics of implant surface topography may alter the production of signaling molecules such as cytokines. The aim of this in vitro study was to evaluate the effects of commercially available titanium surface treatments on both cell viability and the secretion of the antagonist cytokines, IL1β and TGFβ1. Human mononuclear cells were cultured on 10 mm diameter commercially pure titanium (cpTi) disks that were prepared using a turning procedure (control=machined surface) and either acid etched or bio-anodized for 1-7 days. Adhered cells were investigated with respect to cell viability using an MTT assay, and cytokine production was verified using an ELISA assay. The results indicate that surface characteristics did not alter the cell viability at days 1 and 4, although the machined surface presented the highest absorbance values at day 7 (p = 0.0084). Cell viability was reduced throughout the time course for all analyzed surfaces (p < 0.05). On day 4, IL1β levels were significantly higher on bio-anodized compared to acid etched surfaces (p = 0.0097). TGFβ1 did not show differences among the surfaces at days 1 and 4. The responses of non-stimulated mononuclear cells to titanium surfaces suggest only modest effects of the surface treatment and roughness on pro-inflammatory cytokine (IL1β) release. [ABSTRACT FROM AUTHOR]