Human stem cells from apical papilla (hSCAPs) are a promising ectomesenchyme‑ derived cell source with neuronal differentiation potential. Under 3D-neurospheres induction, hSCAPs can be induced into neural stem cells (NSCs) and further committed toward neuronal lineages. This study aimed to demonstrate the differentiation of NSCs‑hSCAPs into neuronal‑like cells undergoing maturation through 3D-neurospheres formation and subsequent neurogenic induction. The characterized hSCAPs were induced into NSCs via 3D-neurospheres formation. The intraspheroidal cells were verified for early neural stemness properties and subsequently dissociated and cultured under neurogenic induction conditions for 7 days. Neuronal differentiation was evaluated by identification of Nissl substance, immunofluorescent analysis of neuronal‑associated proteins, quantitative mRNA expression, and depolarization‑evoked intracellular Ca2+ imaging. Following 3D neurosphere induction, hSCAPs formed clusters of intraspheroidal cells exhibiting typical NSCs characteristics, including high expression of Nestin and SOX2 and self‑reaggregation ability. After 7 days of neurogenic induction, the differentiated cells displayed distinct neuronal‑like morphologies, reduced expression of early neuronal markers (Nestin/NES and SOX2/SOX2), and increased expression of early neuronal differentiation-associated markers (Beta‑III tubulin/TUBB3) at both protein and mRNA levels. The synaptic vesicle‑associated gene (SV2A) was highly detected at the mRNA level. Furthermore, depolarization‑evoked Ca2+ responses after KCl stimulation were observed, indicating membrane excitability and voltage‑gated calcium channel in the differentiated cells. NSCs‑hSCAPs possess the capacity to generate neuronal‑like cells undergoing maturation via 3D-neurospheres formation and neurogenic induction.

This scoping review aimed to evaluate the pellicles' protective potential against mechanical tooth wear and to explore the underlying mechanisms. 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. 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. 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.