Evaluation of Effect of Chlorhexidine on Microleakage of Class-v Composite Restorations with Dentin and Enamel Margins Using Two-stage Self-etch Adhesive after Keeping Them in Water for Six Months

Use of materials with anti-bacterial effects including Chlorhexidine after tooth carving and before placing restorative materials has been prevailed; nonetheless, effect of this solution on amount of microleakage after restoration has been mentioned as one of the challenges to use this solution. With regard to few studies at the area of long term effects of Chlorhexidine on microleakage, the present research was conducted aiming at evaluating effect of Chlorhexidine on microleakage of Class-V composite restorations with dentin and enamel margins using two-stage self-etch adhesive after keeping them in water for six months. The present research has been a quasi-experimental and in vitro study conducted on 102 premolar teeth in Department of Restorative DentistryAhvaz Jundishapur University of Medical Sciences. After creating class V cavities (2.3 mm × 1.5 mm) on the buccal surface of each tooth, teeth were divided into two groups of control(n=51) and treatment(n=51) groups in random. In treatment group, before use of bonding, cavities have been washed with Chlorhexidine and then restorated and the samples have been subjected to thermal cycling at the third month and kept in distilled water for 6 months and observed under Stereomicroscope magnified up to 20 times after being placed in 0.2% Methylene Blue Stock Solution and their buccolingual cut, whereby the results have been recorded based on amount of microleakage by means of dye penetration in gingival and occlusal margins. Findings of this study indicated that there is no significant difference on amount of dentin microleakage in control and treatment groups after six months (P>0.05). Yet, there is a significant difference on amount of enamel microleakage in control and treatment groups after six months (P<0.05). Results of this study indicated that use of Chlorhexidine in Class-V composite restorations before using bonding and after 6 months does not raise microleakage at dentin margin, yet it seems that use of Chlorhexidine in Class-V composite restorations has a negative effect on amount of microleakage at enamel margin. With regard to extensive use of Chlorhexidine in restorative dentistry, further studies on probable effects of this solution on microleakage after restoration are suggested.