14 research outputs found
Using data envelopment analysis for evaluating flexible manufacturing systems in the presence of imprecise data
A decision model for setting target levels in quality function deployment using nonlinear programming-based fuzzy regression and optimization
Biomonitoring of metal(oid)s in mining-affected Borcka Dam Lake coupled with public health outcomes
Multifocal electroretinogram for assessing sun damage following the solar eclipse of 29 March 2006
Antimicrobial resistance and virulence determinants in coagulase-negative staphylococci isolated mainly from preterm neonates
Influence of core-finishing intervals on tensile strength of cast posts-and-cores luted with zinc phosphate cement
The core finishing of cast posts-and-cores after luting is routine in dental practice. However, the effects of the vibrations produced by the rotary cutting instruments over the luting cements are not well-documented. This study evaluated the influence of the time intervals that elapsed between the cementation and the core-finishing procedures on the tensile strength of cast posts-and-cores luted with zinc phosphate cement. Forty-eight bovine incisor roots were selected, endodontically treated, and divided into four groups (n = 12): GA, control (without finishing); GB, GC, and GD, subjected to finishing at 20 minutes, 60 minutes, and 24 hours after cementation, respectively. Root canals were molded, and the resin patterns were cast in copper-aluminum alloy. Cast posts-and-cores were luted with zinc phosphate cement, and the core-finishing procedures were applied according to the groups. The tensile tests were performed at a crosshead speed of 0.5 mm/min for all groups, 24 hours after the core-finishing procedures. The data were subjected to one-way analysis of variance (ANOVA) and Tukey's test (α = 0.05). No significant differences were observed in the tensile strengths between the control and experimental groups, regardless of the time interval that elapsed between the luting and finishing steps. Within the limitations of the present study, it was demonstrated that the core-finishing procedures and time intervals that elapsed after luting did not appear to affect the retention of cast posts-and-cores when zinc phosphate cement was used