Conclusions There is weak evidence indicating length and width of EMCs increase following bracket removal and the scientific evidence concerning quantitative evaluation of the number parameter before and after debonding is insufficient .
However , there is a strong evidence that after debonding the number of EMCs is likely to increase .
Objectives To evaluate and compare the enamel microcracks ( EMCs ) characteristics ( qualitative and quantitative ) in the form of tooth damage before and after debonding from human teeth of in vitro studies .
Enamel cracks and ceramic bracket failure during debonding in vitro.
OBJECTIVE To test the null hypothesis that no difference in bracket failure characteristics is noted when use of a new ceramic bracket debonding instrument is compared with the use of conventional pliers . MATERIAL S AND METHODS Thirty maxillary premolars were r and omly assigned to one of two groups . In group 1 , Clarity collapsible ceramic brackets ( 3 M Unitek , Monrovia , Calif ) were debonded with the use of conventional Utility/Weingart ( 3 M Unitek , Monrovia , Calif ) pliers . In group 2 , Clarity brackets were debonded with a new Debonding Instrument ( 3 M Unitek ) . For all teeth , the same bracket bonding system was used . Following debonding , teeth and brackets were examined under 10x magnification for assessment of bracket failure ( fracture ) and of residual adhesive on the enamel surface . Enamel surfaces were visualized with transillumination prior to bonding and after removal of the residual adhesive , so the effect of the debonding forces could be determined . RESULTS The results of Adhesive Remnant Index comparisons indicated that a statistically significant difference ( chi2 = 8.73 ; P = .013 ) in bond failure patterns was apparent when the two groups were compared . Brackets debonded with the new instrument showed a greater tendency for the adhesive to be removed from the tooth during debonding . CONCLUSIONS The hypothesis is rejected . Although the incidence of enamel damage following debonding was similar in the two groups , the use of the new Debonding Instrument decreased the incidence of bracket fracture
Conclusions There is weak evidence indicating length and width of EMCs increase following bracket removal and the scientific evidence concerning quantitative evaluation of the number parameter before and after debonding is insufficient .
However , there is a strong evidence that after debonding the number of EMCs is likely to increase .
Objectives To evaluate and compare the enamel microcracks ( EMCs ) characteristics ( qualitative and quantitative ) in the form of tooth damage before and after debonding from human teeth of in vitro studies .