Smooth surface enamel defects could benefit from sealants. The objectives of this study were to determine bond strength of a sealant on defective enamel compared to normal enamel and to evaluate the etch patterns on both. Thirty-six extracted permanent molars were used in this study. Ten molars with normal enamel surfaces and ten molars with defective enamel surfaces were used to measure bond strengths using an Instron Universal testing facility. Ten molars, half with normal and half with defective enamel were used to evaluate etching patterns using scanning electron microscopy (SEM). Six teeth, three with normal and three with defective enamel, were used to examine application and adaptation of sealant to smooth surface enamel using a dissec­tion microscope. Bonding of sealant to normal enamel (16.90 ± 8.08 MPa) was significantly greater than that to defective enamel (9.06 ± 5.39 MPa), (t = 2.55, P 3= 0.02). SEM examination of etched normal enamel showed mostly type 2 etching patterns. In contrast,