Effects of toothpaste detergents on oral cell viability

Objectives: To observe the in vitro response of oral mucosal like cells to the presence of detergents commonly used in commercial toothpaste formulations. Methods: TERT-1 Keratinocytes, analogous to oral mucosal cells were exposed to varying concentrations of four toothpaste detergents as well as PBS and culture medium (type). Toothpaste detergents used were Adinol, Sodium Lauryl Sulphate (SLS) and Pluronic (all 0.25-1%) and Tego Betain (0.081 – 0.325%). After 2-minute exposure, cells were washed and incubated in fresh medium for 24 hours. Cell viability was then spectrophotmetrically measured using an MTT ((3-(4, 5-dimethylthiazolyl-2)-2, 5-diphenyltetrazolium bromide))assay. Results: Except for Pluronic, cell viability was markedly reduced for all detergents at all concentrations when compared to the positive medium control (P<0.01). This decreased viability was more evident at higher detergent concentrations. In contrast cells treated with Pluronic were more stimulated than those exposed to medium alone, especially at lower concentrations (0.081.%). Conclusions: Though this study was in vitro, these data suggest that some detergents may have the potential to cause soft tissue damage in the mouth. However, it is likely neutralising effects in the mouth such as that produced by saliva may reduce any harmful effects. The results of exposure to Pluronic suggest a possible carcinogenic or hyperplasic action that bears further study.