The effect of placing sealants after cavity disinfection with erbium, chromium: ytrium-scandium-gallium-garnett laser and casein phosphopeptide – amorphous calcium phosphate on bond strength and microleakage

The aim of this study is to evaluate the effects of Er,Cr:YSGG laser disinfection, CPP-ACP containing paste and sodium hypochlorite application before the placement of a resin based pit and fissure sealant on the shear bond strength to primary tooth enamel and microleakage properties. Shear bond strength test method was selected to evaluate the bond strength of the groups. Buccal enamel surfaces of primary molar teeth were used. For the control group resin based pit and fissure sealant was used according to manufacturer's instructions. For the experimental group samples disinfection with Er,Cr:YSGG laser, disinfection with Er,Cr:YSGG laser and CPP-ACP containing paste, sodium hypochlorite, sodium hypochlorite and CPP-ACP containing paste, CPP-ACP containing paste applications were done before sealant placement. The pit and fissure sealants were placed using 4 mm diameter, 2 mm height cylindrical plastic tubes. Shear force was applied to each sample at a crosshead speed of 1 mm/min until failure occured. The surfaces of the broken samples were detected under stereomicroscope and were grouped as adhesive, cohesive and mix. Dye penetration method was selected fort he microleakage test. The same groups of the shear bond strength test were used for the microleakage test. Thermal cycling was applied for 500 times. After keeping them in a %0,5 methylene blue solution for 24 hours, teeth were cut into 3 pieces in the bucco-lingual direction and the outer surfeces were detected under a stereomicroscope. Dye penetration levels were recorded in accordance with determined scores. The groups which sodium hypochlorite and sodium hypochlorite with CPP-ACP applied showed lower bond strength (p<0,05). It was observed that most of the failures occured in these groups were adhesive type failures. No significant difference was observed between the shear bond strengths of the other groups (p<0,05). According to the microleakage test results, the groups which sodium hypochlorite and sodium hypochlorite with CPP-ACP applied showed higher microlekage (p<0,05). However, there was no difference between the microlekage of the other groups (p<0,05).