Different Application Strategies When Using Ambar Universal in Class V Cavities

Treatment clinical trial, randomized, controled, parallel, double-blinded, with four groups, that aims to evaluate the best application strategy when using a new Universal Adhesive system, Ambar Universal (FGM, Joinville, Brazil). 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. 38 enrolled patients will receive four 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. 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 55 teeth, according to the manufacturer's instructions, in the self-etching mode. The adhesive system will be brushed during 10 seconds in the cavity, will be air-dried during 5 seconds, brushed again during 10 seconds, air-dried during 10 seconds and activated during 10 seconds with Light Emission Diode (LED) light; Group SEE (Selective enamel etching): 37% phosphoric acid will be applied during 15 seconds, only in enamel in 55 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 SETT (Self-Etching with extended time): Similar to Group SET, but during the 2 applications, the adhesive systems will be brushed during 20 seconds, and not during 10 seconds as described in Group SET; Group SETL (Self-Etching with extended number of layers): The adhesive system will be applied as describe in Group SET, but the researchers will apply 4 layers, and not 2 layers, as described in Group SET. After applying the adhesive, the restorations will be made with composite resin, and evaluated every 6 months for pain