Dental hypomineralization such as dental fluorosis has increased in recent times leading to unaesthetic appearance of teeth. There are different treatment possibilities to improve the aesthetic appearance of hypomineralized enamel described in dental literature. The enamel microabrasion has been a feasible alternative, since it is a fast, safe, conservative, and easy to perform, which promotes good esthetic results. Moreover, this technique is a conservative method that improves the appearance of the teeth by restoring bright and superficial smoothness, without causing significant structural loss. The association of different techniques, such as direct composite resin, can provide good esthetic outcomes, but the etiology, intensity, and depth of stain should be considered to minimize dental structure loss. Objective: To describe an easy technique for managing dental fluorosis using enamel microabrasion in association with direct composite resin. Case report: A mixture of hydrochloric acid and silicon carbide was applied according the manufacturer’s instructions. Subsequently, a direct composite resin was applied over the areas where the opacities were more evident. This conservative approach may be considered an interesting alternative treatment to remove fluorosis staining and to improve aesthetic appearance. Conclusion: enamel microabrasion combined with direct composite resin is a conservative and safe alternative method to treat enamel opacities from dental fluorosis. Therefore, this management provides satisfactory aesthetic results for the patient’s smile.

Purpose: The aim of this study was to evaluate the physical-mechanical properties of experimental orthodontic resins, containing different photoinitiators systems and photoactivated through a ceramic bracket, using a high irradiance and wide spectrum light emitting diode curing unit. Methods: Experimental resin composites (50:50 BisGMA/TEGDMA: 60% feldspar silanized particles) were formulated with different photoinitiators according to the following groups: phenylpropaneamine + amine DMAEMA (PPD), camphorquinone + amine DMAEMA (CQ) or bisacylphosphinic oxide (BAPO). A commercial orthodontic resin composite (Transbond XT) was used as control. The materials were then distributed into two groups, according to the photoactivation condition: directly or through a ceramic bracket, for 20s at 1200 mW/cm2. In the sequence, fifteen composite disks, 5mm of diameter and 1mm of thickness, were made for each of the eight groups. The degree of conversion (DC) was determined by means of Raman spectroscopy. Knoop hardness (KHN) was measured immediately after confection and after 24 hours of storage in 100% ethanol for indirect crosslink density (CLD) evaluation. Data were analyzed using two-way ANOVA followed by Tukey's test (α = 0.05). Results: The DC of the BAPO composite was significantly higher in comparison to the other materials, regardless of the photoactivation condition. The KHN was significantly different between the composite groups in the following sequence: BAPO> Transbond XT> CQ> PPD. The direct photoactivation presented higher KHN values, regardless the type of material. Regarding the CLD, there was statistical difference only for the material factor, as follow: PPD> BAPO = CQ = Transbond XT. Conclusion: The photoinitiator type and the photoactivation condition had a significant influence on the physical-mechanical properties of the evaluated materials.

No abstract