Impact of phytosphingosine-enriched experimental toothpaste on dental enamel integrity: a combined in vitro and in situ investigation

Abstract Objective This study evaluated the effects of a phytosphingosine-enriched toothpaste (PET) versus a commercial toothpaste on dental enamel using in vitro and in situ approaches. Materials and methods In vitro , bovine enamel specimens were assigned to one of three brushing agents, artificial saliva, Colgate Total 12, or PET and subjected to simulated brushing (40, 280, 600, and 1,200 cycles), each representing the estimated brushing exposure for 1, 7, 15, and 30 days, respectively. Each group of specimens were evaluated at all time points throughout the 30-day period. Surface roughness and microhardness were measured. In situ , 14 volunteers used appliances containing enamel samples, brushed with the same toothpastes. Roughness, microhardness, and biofilm accumulation were assessed. Atomic force microscopy (AFM) characterized enamel surfaces post-treatment. Results In vitro, PET showed lower surface roughness than saliva at 7 days ( p < 0.05) and results comparable to the commercial product. Microhardness reduction was significantly greater with PET than with the commercial toothpaste at all evaluated time points ( p < 0.05). In situ , no significant differences in roughness or microhardness were observed among groups ( p > 0.05). However, PET significantly reduced biofilm compared to saliva ( p < 0.05). AFM revealed smooth surfaces with both PET and the commercial product. Conclusion This study demonstrated the PHS-enriched toothpaste did not adversely affect enamel integrity and resulted in significantly lower biofilm coverage on enamel, suggesting its potential for use in preventive oral care formulations. Clinical Relevance This study suggests that a phytosphingosine-enriched toothpaste is a promising option for preventive dentistry, as it resulted in lower biofilm accumulation on enamel without compromising enamel integrity. Given the central role of biofilm in the development of caries and periodontal disease, these findings provide scientific support for the future development of safer oral hygiene products as alternatives to conventional agents such as triclosan and chlorhexidine.