Sol-gel derived 45S5 bioactive glass-ceramic micro/nano particles for dentin hypersensitivity: Synthesis, characterization, and in vitro efficacy evaluation

The oral health complications, particularly dentin hypersensitivity (DH), constitute a highly prevalent clinical challenge with a profound negative effect on human well-being and quality of life. This study aimed to evaluate the ability of 45S5-derived bioactive glass-ceramic nanostructured microparticles (45S5-derived BGc) for DH applications. Herein, 45S5-derived BGc was successfully synthesized via the sol-gel method. Comprehensive physical, chemical, and morphological characterization of 45S5-derived BGc was performed using TG/DSC, XRD, XRF, laser diffraction, FTIR, and SEM. To evaluate its potential to treat dentin hypersensitivity (DH), the in vitro bioactivity of 45S5-derived BGc was assessed by immersion in Simulated Body Fluid (SBF) for 14 and 21 days. Subsequent FTIR and SEM analyses revealed morphological and chemical signatures consistent with the formation of an apatite-like phase on the material's surface. Moreover, the preclinical efficacy of the 45S5-derived BGc was assessed using human premolar dentin disks, which were divided into three groups: an untreated control, a group brushed with the 45S5-derived BGc, and a group subjected to demineralization/remineralization cycling. SEM evaluation of dentinal tubule occlusion revealed that the gel-derived 45S5 BGc effectively adheres to exposed dentin and forms a protective mineralized layer. Notably, this occluding layer indicated resilience, exhibiting partial structural recovery even after acidic challenge cycles. These findings highlight the sol-gel-derived 45S5 BGc as a highly promising material with strong in vitro potential for dentinal tubule occlusion.