Cytotoxicity of the Ingredients of Commonly Used Toothpastes and Mouthwashes on Human Gingival Fibroblasts

Abstract

Objectives: Toothpastes and mouthwashes contain ingredients that may be toxic for oral mucosal tissues. This study aimed to assess the cytotoxicity of the ingredients of commonly used toothpastes and mouthwashes.
 Materials and Methods: This experimental study was performed on 16 toothpastes and four mouthwashes widely available in the Iranian market. First, the concentration of six main ingredients of these products, namely sodium fluoride (NaF), sodium lauryl sulfate, cocamidopropyl betaine, zinc lactate, paraben, and sodium benzoate, was determined. The methyl thiazolyl tetrazolium (MTT) assay was used to assess the cytotoxicity of these materials for human gingival fibroblasts (HGFs). The MTT assay was performed at 1, 15, and 30 minutes following exposure to five concentrations of each material in triplicate (according to the concentrations obtained in the isolation step). Data were analyzed using three-way analysis of variance (ANOVA).
 Results: The difference in the cytotoxicity of the materials was statistically significant (P<0.001). Cytotoxicity was time- and concentration-dependent; by an increase in the concentration of the materials, their cytotoxicity increased over time. The cytotoxicity of sodium lauryl sulfate and cocamidopropyl betaine was >90%. The cytotoxicity of NaF varied from 25% to 70%, and the cytotoxicity of all concentrations of zinc lactate and sodium benzoate was <50% for HGFs.
 Conclusion: To decrease the cytotoxic effects of toothpastes, sodium lauryl sulfate and cocamidopropyl betaine should be replaced with safer detergents, and the concentration of fluoride should be decreased to 400 parts per million (ppm). Alternatively, fluoride may be replaced with other antibacterial and cariostatic agents.

In Vitro Biocompatibility of Several Children’s Toothpastes on Human Gingival Fibroblasts

“…These results agree with ours; this preservative is present in Oral B and Vitis Kids, which produced the best results. Paraben is another commonly used preservative which was analyzed that presented low cytotoxicity [ 14 ], which is in Oral B. In summary, all the components present in Oral B had the best results, which agrees with our results, being that Oral B is the most biocompatible children’s toothpaste.…”

“…This finding agrees with our results, since Oral B, which had the best results, is the only toothpaste with this surfactant in its composition. Conversely, Tabatabaei et al [ 14 ] reported moderate cytotoxicity with CPAB. Thus, our results could be explained due to the low concentrations of CPAB in these toothpastes.…”

“…Thus, toothpastes are in contact with human gingival fibroblasts for a long time compared to other oral materials [ 11 , 12 , 13 ]. On the basis of these reasons, some studies investigated the cytotoxicity of different toothpastes [ 14 , 15 , 16 ], finding that the toxicity varies according to the toothpastes’ composition.…”

Cytotoxicity effect of orthodontic miniscrew-implant in different types of mouthwash: An in-vitro study

“…Chlorhexidine was found to be toxic to gingival fibroblast cells[ 17 18 ] and several other cells,[ 19 ] as well as fluoride which was also found to be toxic to gingival fibroblasts with the level of toxicity depending on the concentration and time of exposure. [ 20 ]…”

Comparative antimicrobial efficacy study of different commercially available toothpaste in India: An in vitro study

“…But it has several side effects, e.g., it may cause dyspnea, swelling of the nasal mucosa, and in severe cases, even can lead to anaphylactic shock. It exhibited low levels of cytotoxicity at standard concentrations (Tabatabaei et al, 2019). Sorbitol plays a double role of humectant and sweetening agent, and helps hold the toothpaste formulation together.…”