Age and experience with dental operating microscope: Do these factors influence on the post space preparation and adhesion of glass fiber posts?

This study evaluated the influence of operator's age and experience with dental operating microscope (DOM) on the cleaning of post space walls and on bond strength of glass fiber posts associated with self-adhesive resin cement. Sixty bovine roots were selected. Root canal preparation was performed and roots were filled using gutta-percha/AH Plus. For post space preparation, specimens were divided into four groups (n = 15), according to operator's age and the use of DOM: (1) ≥40 years; (2) ≥40 years with magnification; (3) <40 years; (4) <40 years with magnification. Next, a high-speed bur of the post system and torque-controlled round burs were used for cleaning of post space. Five roots in each group were evaluated for the degree of cleanliness under a stereo microscope using a scoring system. In the remaining 10 specimens from each group, glass fiber posts were cemented with RelyX U200. Two slices (1 ± 0.1 mm) prepared on each root third of all specimens were evaluated by push-out analysis. The scoring system was analyzed using Kruskal-Wallis and push-out data using ANOVA. Significance level was set at 5%. No significant difference was observed in cleaning scores among groups (p > .05). There was no significant difference when comparing the groups and the root thirds (p > .05). The adhesive failure between dentin, cement, and post predominated in all groups. Operator's age and experience with DOM did not influence the cleanliness of root canal walls or the bond strength of glass fiber posts associated with self-adhesive resin cement for post space preparation. RESEARCH HIGHLIGHTS: Although magnification is considered part of Endodontics, little is known about the variables associated. Operator's age and experience with microscope on cleaning of canals and on push-out of posts with self-adhesive resin cement were evaluated.