An in vivo and in vitro study on the effect of tooth liquid polish seaIant on the bond strength of orthodontic brackets / 中国组织工程研究

ABSTRACT

BACKGROUND: BISCOVER LV is a low-viscosity, ligh-cured resin formulation that can be directly coated on the tooth enamel surface for resin polishing inside and outside the mouth or bracket bonding for enamel demineralization. OBJECTIVE: To evaluate the effect of tooth liquid polish sealant on the shear bond strength of orthodontic brackets and the failure rate of bracket bonding. METHODS: (1) In vivo test 30 teenager patients under orthodontic treatment were randomly selected. BISCOVER LV was used to deal with the upper and lower dentitions on the left side, and then the brackets were bonded by a light-cured resin adhesive (Transbond XT). The upper and lower dentitions on the right side were directly bonded with the brackets by Transbond XT. After 1 month, the failure rate of bracket bonding was detected in each patient. (2) In vitro test 60 extracted orthodontic teeth were selected and randomized into two groupsBISCOVER LV group and non-BISCOVER LV group. The following procedures in the in vitro test were the same as those in the in vivo test. Two groups of specimens were thereafter soaked in the artificial saliva, the shear bond strength of the brackets was tested, and then the adhesive remnant index was recorded. RESULTS AND CONCLUSION: (1) In the in vivo test, there was no significant difference in the failure rate of bracket bonding between two clinical groups (11.43% vs. 9.64%; P＞0.05). (2) In the in vitro test, there was no significant difference in the shear bond strength of the brackets[(9.24±2.06) MPa vs. (9.59±2.24) MPa; P＞0.05] as well as in the adhesive remnant index record between the two groups. Therefore, we can make the conclusion that the use of tooth liquid polish sealant for prevention of enamel demineralization has no effect on the bond strength of brackets.