Evaluation of the bonding strength of conventional, anatomized, adjustable, and CAD/CAM milled fiberglass posts in weakened endodontically treated roots

Abstract

This study evaluated the bond strength (BS) of conventional, anatomized, adjustable, and CAD/CAM fiberglass post systems. Forty maxillary canine roots were weakened, endodontically treated, and divided into four groups (n=10). A slice from each of the three sections (cervical, middle, apical) of the root canal was subjected to the push-out test and the failure pattern was subsequently analyzed. The most apical slice was subjected to analysis of the cementation line thickness by scanning electron microscopy (SEM). Data regarding the BS and cementation line thickness were subjected to the Shapiro-Wilk normality test followed by the variance and Tukey tests. Data failure patterns were expressed as a percentage and submitted to the chi-square test. Conventional fiberglass posts had the lowest BD compared to the other fiberglass posts (p<0.05). All fiberglass posts exhibited a higher percentage of adhesive failures to dentin. The SEM demonstrated a thicker cementation line for the conventional post compared to the other groups (p<0.05), as well as gaps and voids in the cementing material. The anatomized, adjustable, and CAD/CAM milled fiberglass post systems demonstrated a superior BS and adaptation to the root dentin compared to the conventional fiberglass post.