Lubricating properties of the dental pellicle: A scoping review

OBJECTIVES: This scoping review aimed to evaluate the pellicles' protective potential against mechanical tooth wear and to explore the underlying mechanisms. METHODS: A systematic search was conducted in Medline, Scopus, and Web of Science up to May 2025. Studies examining pellicles formed on enamel, dentin, or hydroxyapatite, using human saliva or salivary proteins, and subjected to mechanical challenges were included. Studies combining erosion or involving diseased subjects or non-dental substrates were excluded. Only original research articles published in English or German were considered. No supplementary approaches to identify studies were performed. RESULTS: Out of 893 records, 26 studies met the inclusion criteria. The majority focused on pellicles formed on enamel or hydroxyapatite. Outcome measures included wear, abrasion resistance, friction coefficient, and viscoelastic properties. While most studies found that the pellicle reduced friction and wear, its abrasion resistance to high mechanical stress was weak. Since the majority of studies were conducted in vitro, the extent to which these findings apply to the dynamic oral environment is uncertain. CONCLUSIONS: The pellicle may offer limited protection against mechanical wear, primarily through a boundary lubrication regime, while evidence regarding its structural integrity and resistance under mechanical stress remains inconclusive, highlighting the need for further research to validate relevant parameters and clarify underlying mechanisms.