Clinical Steps for Restoration of Fractured Anterior Teeth: Color Protocol with Non-VITA Scale.

Direct composite resin restorations are commonly provided because of their satisfactory esthetics and minimal wear of opposing tooth structure. Recent restorative systems may not follow the nomenclature of the classical VITA shade guide, using instead a simplified resin color system. A better understanding of these systems and their behavior regarding the incidence of light is an excellent approach to anterior restorations, especially for fractured anterior teeth. This paper demonstrates the color selection and clinical sequence for the natural reproduction of tooth structure using a resin system that does not follow the VITA classical scale.

Effect of surface treatments on the bond strength of CAD/CAM fiberglass posts.

BACKGROUND: There is no ideal protocol for the surface treatment of fiber posts, especially when using a computer-aided design/computer-aided manufacturing (CAD/CAM) experimental fiberglass block. The purpose of this study was to evaluate the bond strength of a CAD/CAM customized glass fiber post and core after applying different surface treatment techniques. MATERIAL AND METHODS: Forty premolars were prepared to receive a customized CAD/CAM glass-fiber post and core obtained from an experimental block of glass fiber and epoxy resin. The specimens were randomly distributed in 4 groups (n=10) according to the post and core surface treatment: ETH - 70% ethanol; HP - 24% hydrogen peroxide for 1 minute; ETH/S - 70% ethanol + silane; HP/S - 24% hydrogen peroxide + silane. The universal adhesive containing silane was applied on the posts and prepared post spaces in all groups. The posts were cemented using dual cure resin cement. The specimens were stored in distilled water at 37°C for 24 h, cut (two slices of 1 mm for each root third - coronal, middle, and apical) and subjected to push-out test (0.5 mm/min). Data was subjected to two-way ANOVA (surface treatment and root third) and Tukey's test (α=0,05). RESULTS: There was no significant difference of bond strength values among groups, regardless the surface treatment (p >0.05). There was significant difference on bond strength values for the different root thirds (p<0.05) (coronal>middle=apical). CONCLUSIONS: The different surface treatment and application of additional silane in the CAD/CAM customized glass-fiber post and core does not interfere on bond strength values. The root dentin third interfered on the bond strength, with higher values for the coronal third. Key words:Post and core technique, cad/cam, shear strength, hydrogen peroxide.