Biocompatibility of self-adhesive resin cement with fibroblast cells.

STATEMENT OF PROBLEM: Dental cements that release monomers that negatively impact adjacent oral soft tissues may adversely affect clinical outcomes. However, in vitro studies evaluating the cytotoxic and genotoxic potential of substances released from dental cements are lacking. PURPOSE: The purpose of this in vitro study was to define and compare the cytotoxicity and genotoxicity of the eluates of a self-adhesive resin cement (RelyX Unicem 2 Automix) autopolymerized and light polymerized with 2 other types of luting cements: a glass ionomer cement (Ketac Cem Easymix) and a resin-modified glass ionomer cement (Ketac Cem Plus). MATERIAL AND METHODS: The eluates were prepared, and 3T3 mouse fibroblast cells were exposed for 24 hours to serial eluate dilutions of the 3 types of cement. Cytotoxicity was determined by using a cell viability assessment through 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) and crystal violet assays. Genotoxic effects were determined by using the cytokinesis-block micronucleus assay. RESULTS: Cell viability was higher in the presence of the glass ionomer cement eluate than of the resin-modified glass ionomer cement and resin cement eluates. A pronounced decrease in viability was found when the cells were exposed to undiluted samples of resin-modified glass ionomer cement (around 50%) or resin cement (around 80% to 90%). No significant difference in cell viability was found between autopolymerized and light-polymerized resin cements. All cements induced a dose-dependent response of mononucleated cell formation. However, only the resin cements showed double strand breaks significant differences in the deoxyribonucleic acid (DNA) molecules against the basal DNA lesions that occurred spontaneously. CONCLUSIONS: The glass ionomer cement was not found to be cytotoxic or genotoxic, whereas the eluates derived from the resin-modified glass ionomer cement and resin cement, independently of the polymerization method, were cytotoxic in fibroblast cells. Maximum cytotoxicity was observed in the presence of resin cement, which also showed genotoxicity, independently of being light polymerized.

Risk Factors for Implant Failure and Peri-Implant Pathology in Systemic Compromised Patients.

PURPOSE: To identify the possible risk factors for implant failure and peri-implant pathology in a population of systemically compromised patients. MATERIALS AND METHODS: This retrospective clinical study included a total of 721 systemically compromised patients (422 women, 299 men), with an average age of 51 years (range: 20 to 87) rehabilitated with dental implants. The average follow-up time was 7.3 years. The patients' demographic variables (age and gender) and clinical variables (implant location, type of implant surface, and systemic conditions) were recorded. Outcome measures were implant failure and peri-implant pathology. Binary logistic regression models were performed to investigate the effect of the patients' demographic and clinical characteristics on the dependent variables implant failure and peri-implant pathology. A linear regression model was performed to correlate the patient's characteristics with the number of failed implants. Odds ratios (OR) with 95% confidence intervals and corresponding levels of significance were estimated for each variable. RESULTS: Multivariate logistic regression disclosed increased age (patients over 40 years of age) as a risk factor for implant failure (OR = 2.63) and hepatitis as a risk factor for peri-implant pathology (OR = 3.74). Multivariate linear regression disclosed rheumatologic and cardiac diseases to be correlated with a higher number of failed implants. CONCLUSIONS: Within the limitations of this study, the results suggest no absolute contraindications for implant rehabilitation in a population of systemically compromised patients. Nevertheless, this study suggests that increasing age, rheumatological condition, cardiovascular condition, and hepatitis should be considered when performing implant-supported rehabilitations due to their negative influence on the outcome.