EffEffect of chlorhexidine as a vehicle for sodium perborate in non vital tooth bleaching on microleakage of resin composite
Objective To study the effect of chlorhexidine (CHX) as a vehicle for sodium perborate (SP) on microleakage of resin composite by using glucose filtration. Materials and methods Thirty six single rooted teeth were used. The specimens with cavity were prepared and divided into three groups: Group 1, SP mixed with 2% CHX; Group 2, SP mixed with distilled water; Group 3, SP mixed with 30% hydrogen peroxide. With a total conduction of three times, bleaching agent was applied in the cavities for 1 week and rinsed. The cavities were then filled with resin composite. The specimens were thermocycled for 500 cycles, followed by a microleakage determination (glucose filtration) The concentration of leaked glucose was analyzed by spectrophotometer. Dentin surfaces of each group were prepared and observed under SEM. Results Mean concentrations and standard deviations of leaked glucose (mM) were 1.001 0.147, 1.005 0.093, and 1.304 0.406, in Groups 1, 2, and 3, respectively. Inter group significant differences were found by a one way ANOVA (p 0.05) Using the post hoc Tukey HSDus test analysis, some significant differences were found between Groups 1 and 3, together with Groups 2 and 3 (p 0.05) The morphology of dentin surfaces under SEM of Group 1 showed mild erosion similar to that of Group 2. Group 3 showed more eroded dentin. Conclusion Using CHX as a vehicle for SP in this study did not affect the microleakage of resin composite and dentin. Clinically, CHX may be a good vehicle for non vital tooth bleaching. (CU Dent J. 2016;39:9 18) Key words: chlorhexidine; glucose filtration; microleakage; non vital tooth bleaching; sodium perborate