ĐÁNH GIÁ ĐỘC TÍNH CỦA NƯỚC SÚC MIỆNG CHỨA CHLORHEXIDINE VÀ CHLORINE DIOXIDE LÊN NGUYÊN BÀO SỢI NƯỚU NGƯỜI

Abstract

Background: Although chlorhexidine is considered to date a gold standard of antimicrobial rinses that reduces biofilm and has been shown to reduce gingivitis and halitosis, its prolonged usage can have several adverse effects, including extrinsic tooth staining. Chlorine dioxide is a highly antibacterial substance for purifying water sources and has recently been used in dentistry. This agent has also been proven safe for human cells. Combining chlorhexidine and chlorine dioxide may reduce the disadvantages of chlorhexidine while still ensuring antibacterial ability. Still, the toxicity of the mixture to the oral environment needs to be evaluated before examining its antimicrobial effect. Objectives: To investigate the toxicity of mouthwash that contains chlorhexidine and chlorine dioxide on human gingival fibroblast. Materials and methods: Human gingival fibroblasts were incubated with the mouthwash solutions containing chlorhexidine and chlorine dioxide at the corresponding concentrations: solution A (chlorhexidine 0.01%, chlorine dioxide 0.05%), solution B (chlorhexidine 0.02%, chlorine dioxide 0.01%), and C (chlorhexidine 0.05%, chlorine dioxide 0.05%), with contact times simulating actual gargling times of 30 seconds, 60 seconds, 90 seconds, 120 seconds, 150 seconds and 180 seconds. The effect of those solutions on human gingival fibroblast was determined by the MTT (3-(4.5-Dimethylthiazol-2-YL)-2.5- diphenyl tetrazolium bromide) method. The Formosan crystals collected were dissolved in Ehthanol/DMSO solution, and the formed purple solution was absorbed at a 570 nm wavelength. The cellular toxicity grades were determined according to ISO 10993 - 5: 2009; cell morphology and the relative growth rate were also observed. Results: In 30 to 90 seconds, solution A did not affect the survival of the human gingival fibroblast (cellular toxicity level 1 with a relative growth rate of 75-99%). Solutions B and C were toxic for the fibroblasts during the timeline. Conclusions: Human gingival fibroblast can be safe in a mixing solution containing 0.01% chlorhexidine and 0.05% chlorine dioxide for up to 90 seconds.