In Vitro Cytotoxic and Remineralization Effects on the Tooth Enamel Surface of Theobromine after the Artificial Induction of Dental Carious Lesions

Background: Theobromine is a methylxanthine alkaloid, and it is mainly found in cocoa and chocolate. It has the ability to enhance the size of hydroxyapatite crystals in enamel, leading to precipitation on the enamel surface and slowing down the breakdown of hydroxyapatite. Objective: This experimental study is to evaluate and compare the cytotoxic activity and remineralization effect on dental enamel between theobromine and sodium fluoride following the creation of artificial carious lesions. Materials and Methods: The study consisted of two components: In the first segment, theobromine’s cytotoxic effects were examined on a human being’s ordinary cell line created from human fibroblasts from the skin, using the Mosmann tetrazolium dye assay. The plates were incubated with theobromine at the following concentrations: 50, 100, 200, and 400 mg/L under 5% CO 2 at 37°C. Each concentration, along with the negative control cells without tested material, was tested in triplicate. In the second part of this study, 34 healthy human premolars were randomly allocated to three groups with 11 teeth each. After they had formed artificial carious lesions, group 1 received theobromine, group 2 received sodium fluoride, and group 3 received artificial saliva as the negative control. The treatment solution was delivered dynamically by utilizing a pH-cycling model. Samples were examined through scanning electron microscopy and energy-dispersive X-ray analysis. The data were statistically analyzed. Results: There was no significant difference between theobromine’s cytotoxicity and the negative control on the normal human cell line ( P > 0.05). However, the atomic percentages of calcium (Ca) and phosphorus (P) were significantly higher ( P < 0.05) in theobromine-treated teeth compared to fluoride-treated teeth. Conclusion: Due to its toxicity and beneficial remineralization effect, theobromine shows promise as an effective and viable alternative to sodium fluoride.