The Effect of Topical Application of Strontium on Bond Strength in Orthodontics. (In Vitro Study)

Abstract

Objective: to evaluate the effects of topical application of strontium on bond strength in orthodontics in vitro by using Instron universal testing machine . Materials and Methods: forty eight bovine enamel specimens were randomly allocated to four groups (n =12). Specimens of group I were not demineralized and were not pretreated, but served as controls. The other specimens were demineralized by using Featherstone pH cycling technique to form artificial carious lesions. Samples from group II were only demineralized. The other samples were pretreated with strontium chloride solution(Srcl2) for 5 minutes. Teeth in groups III were treated with Srcl2 solution before acid-etching. Teeth in groups IV were treated with Srcl2 after acid-etching. The brackets were then bonded .The brackets' SBS was measured and the adhesive remnant was assessed using adhesive remnant index (ARI). Analyses were done for SBS values between the four groups using One-Way ANOVA test followed by Post Hoc Tukey’s analysis between each two groups .Fisher’s exact test was used to evaluate differences in ARI scores between the groups. Results: srcl2treated group before acid etching )showed the highest mean SBS value when compared to other groups (Mean ± SD =24.7±7.4 MPa). There was insignificant difference between the four groups as regarding ARI scores (p=0.406). Conclusion: The topical application of srcl2 did not compromise the bond strength of orthodontic brackets to demineralized bovine enamel.