Treatment clinical trial, randomized, controled, parallel, double-blinded, with three groups, that aims to evaluate if there is some advantage in applying surface sealants (Biscover, Bisco, USA or Permaseal, Ultradent, USA) associated with a Bulk Fill Composite (Tetric N-Ceram Bulk Fill, Ivoclar Vivadent,Liechtenstein). 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. 53 enrolled patients will receive 159 Class I or Class II dental restorations, made in three different ways, one from each experimental group (no sealant, or one of the evaluated surface sealants). Occlusal or Proximo-occlusal lesions will receive the selected treatments separated by groups. Group Bulk without surface sealant (BNS), Group Bulk and Biscover (BSB), and Group Bulk and Permaseal (BSP). Immediate post-operative tooth sensitivity will be evaluated after one week. Restorations will be evaluated every 6 months for pain assessment, shape, fractures, staining or recurrent caries, using scores. To determine in which group each tooth will be enrolled, the authors will randomize the teeth.

This is a Treatment clinical trial, randomized, controlled, parallel, double-blinded, with three groups, that aims to evaluate if there is some advantage in applying surface sealants (Biscover, Bisco, USA or Permaseal, Ultradent, USA) associated with a Bulk Fill Composite (Tetric N-Ceram Bulk Fill, Ivoclar Vivadent, Liechtenstein). 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 53 enrolled patients will receive 159 Class I or Class II dental restorations, made in three different ways, one from each experimental group, using the same self-etching adhesive system, under the restorations that will use the same bulk fill composite. All patients must have at only 20 teeth in function, must have at only 3 carious lesion in occlusal or proximo-occlusal face in posterior teeth or old restorations in the same faces, with problems, that need to be changed. Those lesions must be more than 2 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. Occlusal or Proximo-occlusal lesions will receive the restorative procedurs in 3 different protocols separated by groups. Group Bulk without surface sealant (BNS): the adhesive system will be used in 53 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 photoactivated during 10 seconds with Light Emission Diode (LED) light. Then, the Tetric N-Ceram Bulk fill composite will be used in increments of 4 mm, using the bulk restoration technique, and photoactivated for 40 seconds; Group Bulk and Biscover (BSB): adhesive and restorative procedures will be performed as described in group BNS in 53 teeth. After the restorations are concluded, Biscover surface sealant will be applied according to the manufacturer's instructions; Group Bulk and Permaseal (BSP): adhesive and restorative procedures will be performed as described in group BNS in 53 teeth. After the restorations are concluded, Permaseal surface sealant will be applied according to the manufacturer's instructions. Immediate post-operative tooth sensitivity will be evaluated after one week. Restorations will be evaluated every 6 months for pain assessment, shape, fractures, staining or recurrent caries, using scores. To determine in which group each tooth will be enrolled, the authors will randomize the teeth.

Inclusion Criteria:

• All patients must have at only 20 teeth in function, must have at only 3 carious occlusal or proximo-occlusal lesions, or old restorations that need to be changed, in different teeth. Those lesions must be more than 2 mm deep, should have exposed dentin, and must have at only 50% of margins in enamel. Teeth should not present periodontal mobility.

Exclusion Criteria:

• Volunteers with periodontal disease; with gingival bleeding; use of anti-inflammatory drugs in the last 30 days.