Cytoxicity of root canal antiseptics used in dental practice on L929 fibroblasts: calcium hydroxide powder vs. 2% chlorhexidine solution

Background & Objective: Chlorhexidine solution is one of the widely used mouth antiseptic liquid that prevents teeth tissue damage and also has application as a root canal antiseptic. In this study, cytotoxicity of 2% chlorhexidine solution is compared with another root canal antiseptic, calcium hydroxide powder.Materials and Methods: Cell cytotoxicity of both chemicals was assessed on cultured L929 fibroblastic cell line for 1,12, 24, 48 and 72 hours using MTT assay (Methyl tetrazolium bromide assay). Untreated L929 cells were used as a negative control group. MTT results were recorded by ELISA reader and analyzed using one-way ANOVA statistical tests.Results: Cytotoxicity of studied chemicals showed significant difference in various dilutions and times (1, 12, 24, 48 and 72 h). The highest cytotoxic effect of 2% chlorhexidine solution was observed in concentration of 0.016% for 72 h. Treatment of cells with 0.016% of 2% chlorhexidine liquid and calcium hydroxide powder for 72 hours showed 80% and 45% cytotoxicity, respectively.Conclusions: Cytotoxicity of calcium hydroxide is significantly less than 2% chlorhexidine liquid and then application of calcium hydroxide powder as root canal antiseptic is recommended

Genetic polymorphisms of glutathione S-transferase Mu 1, glutathione S-transferase theta 1, and glutathione S-transferase P1 in oral squamous cell carcinoma: A case-control study in Iranian population

Background: Gene variability related to activation and detoxification of procarcinogens affects the susceptibility to oral squamous cell carcinoma (OSCC). The results of numerous studies investigating the interrelationship between polymorphisms of glutathione S- transferase enzymes are not conclusive and there are little data regarding this topic on Iranian population. Aims and Objectives: This study aimed to investigate the genetic polymorphisms in glutathione S-transferase Mu 1 (GSTM1), glutathione S-transferase theta 1 (GSTT1), and glutathione S-transferase P1 (GSTP1) and the association with the risk of OSCC in Iranian population. Materials and Methods: The genetic polymorphisms of GSTM1, GSTT1, and GSTP1 genes were investigated in 35 Iranian patients with the OSCC and 60 age-sex matched controls. GSTP1 genotyping was performed by polymerase chain reaction (PCR)-restriction fragment length polymorphism method and GSTM1 and GSTT1 genotyping was amplified with PCR using specific primers. Odds ratios (ORs) and their 95% confidence intervals (CIs) were obtained using SPSS 17 and the risk of OSCC in relation to GSTM1, GSTT1, and GSTP1 polymorphism was defined. Results: The prevalence of GSTM1 and GSTT1 null genotypes in OSCC group were significantly higher than the control group.(OR = 2.6, 95% CI = 1.04-6.5; P = 0.01 for GSTM1) (OR = 11, 95% CI = 9-31; P = 0.001 for GSTT1). The GSTP1 valine polymorphism was not significantly different between the study groups (P = 0.145). Conclusions: GSTM1 and GSTT1 null genotypes may increase the risk for OSCC development in Iranian patients