how is the enamel affected by different orthodontic bonding agents and polishing techniques?

o bjectives: the objective of this study was to assess the effect of new bonding techniques on enamel surface. materials and methods: sixty upper central incisors were randomly divided into two equal groups. in the first group, metal brackets were bonded using trans- bondxt and, in the second group, the same brackets were bonded with maxcemelite. the shear bond strength (sbs) of both agents to enamel was measured and the number and length of enamel cracks before bonding, after debonding and after polishing were compared. the number of visible cracks and the adhesive remnant index (ari) scores in each group were also measured. r esults: there were significantly more enamel cracks in the transbond xt group after debonding and polishing compared to the maxcem elite group. there was no significant difference in the length of enamel cracks between the two groups; but, in each group, a significant increase in the length of enamel cracks was noticeable after debonding. polishing did not cause any statistically significant change in crack length. the sbs of maxcem elite was significantly lower than that of transbond xt (95% confidence interval). c onclusion: maxcem elite offers clinically acceptable bond strength and can thus be used as a routine adhesive for orthodontic purposes since it is less likely todamage the enamel.