This is a Treatment clinical trial, randomized, controlled, parallel, double-blinded, with four groups, that aims to evaluate the best application strategy when using a new Universal Adhesive system, Futurabond Universal (VOCO GmbH, Germany). Volunteers will be selected and recruited,following inclusion criteria and pre-established exclusion. All volunteers will be informed and sign a term of clarification and consent. All 50 enrolled patients will receive Class V dental restorations, made in four different ways, one from each experimental group, using the same universal self-etching adhesive system, which is the tested material in this study. All patients must have at only 20 teeth in function, must have at only 2 non carious cervical lesions (NCCL), in different teeth, that need restoration. Those lesions must be non carious, must be more than 1 mm deep, should have exposed dentin, and must have at only 50% of margins in enamel. Teeth should not present periodontal mobility. Firstly, the patient will be anesthetized locally with 3% Mepivacaine solution, followed by prophylaxis with pumice powder and water. All cavities will be washed and dried after these procedures for optimal selection of color, using a color scale. Then, the rubber dam isolation of the teeth to be restored will be held. Non-carious cervical lesions will receive the applied adhesive system in 4 different protocols separated by groups. Group Self Etching (SET) (control): no conditioning, the adhesive system will be used in 50 teeth, according to the manufacturer's instructions, in the self-etching mode. The adhesive system will be brushed during 20 seconds in the cavity, will be air-dried during 5 seconds, and activated during 10 seconds with Light Emission Diode (LED) light; Group SEE (Selective enamel etching): 37% phosphoric acid will be applied during 30 seconds, only in enamel in 50 teeth. This acid will be removed using water, the cavity will be air-dried, and then, the adhesive will be applied according to the manufacturer's instructions, as described in group SET; Group ERDry (Etch& Rinse Dry): 37% phosphoric acid will be applied during 30 seconds, only in enamel and during 15 seconds only in dentin, in 50 teeth. This acid will be removed using water, the cavity will be air-dried, keeping dentin dry, and then, the adhesive will be applied according to the manufacturer's instructions, as described in group SET; Group ERWet (Etch& Rinse Wet): 37% phosphoric acid will be applied during 30 seconds, only in enamel and during 15 seconds only in dentin, in 50 teeth. This acid will be removed using water, the cavity will be air-dried, keeping dentin wet, and then, the adhesive will be applied according to the manufacturer's instructions, as described in group SET. After applying the adhesive, the restorations will be made with composite Admira Fusion (VOCO GmbH, Germany), and evaluated every 6 months for pain assessment, shape, staining or recurrent caries, using scores. To determine in which group each tooth will be enrolled, the authors will randomize the teeth.
