Objectives: Oral submucous fibrosis (OSMF) is a chronic inflammatory disease and a potentially malignant oral disorder. However, the best therapeutic treatment for OSMF remains uncertain. Our previous study showed that photobiomodulation (PBM) therapy and forskolin could reduce arecoline‐induced fibrosis reactions via the cAMP pathway. The present study aimed to establish an animal model of areca nut extract (ANE)‐induced OSMF and to evaluate the therapeutic potential of PBM and forskolin for ANE‐induced OSMF.Subjects and methods: The mice were divided into five groups. The buccal tissues were harvested for histomorphological analysis and immunoblotting.Results: Our results showed that PBM significantly reduced the development of ANE‐induced OSMF, quantified by changes in submucosal layer thickness and collagen deposition. Additionally, PBM could extensively reduce the protein expression of the fibrotic marker genes alpha‐smooth muscle actin (α‐SMA) and connective tissue growth factor (CTGF) in buccal submucous lesions. However, forskolin treatment significantly decreased the protein expression of fibrotic marker genes but slightly decreased the observed histomorphological changes.Conclusions: We established an ANE‐induced OSMF mouse model, which also provided a model for the development of a therapeutic treatment for OSMF. The anti‐fibrotic effects of PBM and forskolin may be useful for clinical interventions.

Background: We aimed to investigate the load-induced strain variation in teeth with unrestored and resin-based composite restored non-carious cervical lesions (NCCLs). Methods: Twelve extracted premolars were provided for measuring buccal-side root NCCLs. Strain gauges were fixed at four measuring sites of each tooth, two at the buccal surface and two at the lingual surface. NCCLs were prepared with occlusal margins at the cemento-enamel junction. A static 9-kg load was applied at seven occlusal loading points: buccal cusp tip (BC), inner inclination of the BC, lingual cusp tip (LC), inner inclination of the LC, center of the mesial marginal ridge or distal marginal ridge, and center of the central groove. The strain was detected at each site in teeth with NCCL depths of 0 (control), 0.5, 1.0, and 1.5 mm. Each NCCL was restored using an adhesive composite resin, and the strains were re-measured. Results: The strains at the NCCL occlusal and gingival margins decreased with increasing defect depths, and the effect was significant when the depth of the defect was 1.5 mm. Loading on the buccal and lingual cusps induced prominent strain variation. The strains at all depth distribution recovered to nearly intact conditions when the NCCLs were restored. Conclusions: NCCLs at 1.5 mm depth are detrimental, but they can be restored using resin composites. Clinical significance: The existence of NCCLs should not be ignored. The depth of the NCCL may affect the progression of the lesion. Resin composite restoration is an appropriate method for preventing persistent NCCL deterioration.

Currently, the development of biomaterials has focused on having a low Young’s modulus, biocompatibility, corrosion resistance, and antibacterial properties. Ti–Nb alloys have higher research value due to their excellent corrosion resistance and low Young’s modulus. In recent years, the antibacterial properties of materials have been enhanced by the addition of Ag and Cu. Therefore, the corrosion resistance and antibacterial properties of the Ti–12Nb–1Ag alloy formulated in the current study were investigated and compared to those of commonly used Ti alloys, G2 pure Ti (ASTM B348 CP Grade 2), and Ti–6Al–4V, via electrochemical and E. coli antibacterial tests. Meanwhile, we also carried out a microstructural analysis to investigate the composition of the alloy. The results were as follows: (1) The electrochemical test demonstrated that Ti–12Nb–1Ag had a higher corrosion resistance than Ti–6Al–4V, which is similar to the properties of pure Ti. (2) The E. coli antibacterial test demonstrated that the sterilization rate of Ti–12Nb–1Ag was higher than that of the Ti–6Al–4V alloy and pure Ti. (3) The microstructural analysis revealed that Ti–12Nb–1Ag had an acicular martensite structure, with nano-Ag precipitates observed. Based on the results of the E. coli antibacterial test and the principles of sterilization of nano-precipitates and Ag, we inferred that the nano-Ag precipitates of Ti–12Nb–1Ag enhanced the antibacterial properties of the newly developed biomaterial, which is, namely, the Ti–12Nb–1Ag alloy.