Search

Objective. This article is a brief review about in vitro proposals to overcome the low bond strength values to bleached dental surfaces through a one-year follow-up case report of the immediate replacement of composite resin restorations after enamel bleaching. Clinical considerations. The presence of residual oxygen after bleaching may be responsible for inhibiting the polymerization of the monomers present in the adhesive systems, leading to the failure of the restorative procedure. The use of antioxidants, especially the 10% sodium bicarbonate solution (SB), could be a fast and practical alternative to improve the bond strength of these restorations. In office bleaching with hydrogen peroxide 35% (Lase Peroxide Sense, DMC, Ribeirão Preto, SP, BRA) was performed followed by the removal of the unsatisfactory restorations. Then, the BS was applied and the new adhesive restorations were placed. After one year, the clinical performance of the restorations were successful, showing no signs of failure nor infiltration. Conclusions. The use of the 10% sodium bicarbonate in bleached enamel seems to be a viable alternative for clinical practice.

The technique of enamel microabrasion is considered an aesthetic alternative conservative and effective for stain removal or surface irregularities of the enamel and different materials or pastes can be used for this purpose Objetives: The objective of this study was to compare the efficiency of the technique of enamel microabrasion using two different pastes at removing hypoplastic stains by fluorosis. Methods: The female patient, 18 years, was submitted to enamel microabrasion, and in the right half of the maxilla was manipulated in the proportion of 1:1 by volume a paste of pumice (SSWhite) and 37% phosphoric acid (Etch Alpha, DFL), and in the left half of the maxilla used paste based on hydrochloric acid and 6.6% silicon carbide (Micropol, DMC Equipment Ltd.). In both hemi-arches was performed the same clinical protocol and repeated three times, by the application of 1.0 mm thickness of paste and realized the enamel microabrasion through mechanical friction with rubber cup at low speed for 10 seconds. Then, the teeth were polished with felt disc and diamond paste, and topical fluoride APF 1.23% for 3 minutes was applied. Results: The clinical outcome was similar for both hemi-arches, regardless of the used technique. The success in removing stains on tooth enamel is directly related to a correct diagnosis and accurate indication of microabrasion technique. Conclusions: It can be concluded that the two pastes used in the enamel microabrasion were effective for removing intrinsic stains from fluorosis, with similar results and with the re-establishment of aesthetics of the teeth involved.

Water contributes to the setting reaction of self-adhesive luting cements, however, it can also accelerate their degradation. Objectives: The aim of this study was to compare a self-adhesive resin luting cement to other resin-based and glass-ionomer luting materials with regards to water sorption (WS) and solubility (WSB). The tested null hypothesis was that there is no difference in respect to these properties among the materials. Material and methods: Eight specimens from each group (15 mm x 0.5 mm) were prepared from self-adhesive luting cements Biscem (BC) and RelyX Unicem (R), dual-cure cements Bifix (BF), Allcem (A) and Enforce (E), chemical-cure cements C&B (CB) and Cement Post (CP) and a glass-ionomer luting cement Meron C (M) as the control group. The dual-cure products were light-cured beneath an IPS Empress Esthetic ceramic disk (20 mm x 1.5 mm) and for the chemical reaction materials, a 15 min-interval was respected for removal from the mould. The WS and WSB were respectively calculated as (m2-m3/V) and (m1-m3/V). Mass values of m1, m2 and m3 were determined by cycles of desiccation, water-immersion and a new desiccation. For each property, the data was analyzed by one-criteria ANOVA and Tukey tests (p < 0.05). Results: The glass-ionomer cement presented the highest WS, followed by the self-adhesive luting cements. Other resin cements were less susceptible to WS. No materials differed from each other when the WSB was considered, except for the M, which presented the lowest WSB. Conclusions: Self-adhesive luting cements were more prone to WS since water is essential to their setting reaction. However, their WSB was similar to the other resin-based cements.