00000nam a22000004a 4500 UP-8027390931313251717 Buklod 20260115101454.0 m |o d | cr ||||||||||| 250915s xxu r |||| u|eng d UPMNL Dent rda eng LG995 2024 D45 G85 Gulmatico-Dela Cruz, Marie Carmina Author A Comparative SEM-EDX Study on the Enamel Remineralization Potential of Bioactive Glass 45S5 and Nanohydroxyapatite in a Novel Orthodontic Adhesive Used to Bond Orthodontic Brackets on Bovine Teeth/Marie Carmina Gulmatico-Dela Cruz. 216 leaves color illustrations 28 cm. text rdacontent unmediated rdamedia other (Unmediated carriers) rdacarrier Thesis (Master of Science in Dentistry)--University of the Philippines Manila. Enamel demineralization, often manifesting as white spot lesions, affects approximately 96% of patients undergoing fixed orthodontic treatment. Traditionally, fluoride has been the primary agent for enamel remineralization; however, recent advancements have highlighted the effectiveness of bioceramics,particularly bioactive glass 45S5 (BAG) and nanohydroxyapatite (NHAp). This study explores a novel approach by incorporating bioceramics into a commercially-available flowable composite to create a remineralizing orthodontic bracket adhesive resin cement. Sixty bovine teeth were prepared and assigned to five groups: baseline, 3M Transbond XTTM, GC Fuji Ortho LCTM, 15% BAG, and 10% NHAp. Each tooth was bonded with an orthodontic bracket using the respective cement. The samples underwent a 9-day pH cycling regimen, following the Toda and Featherstone protocol. Qualitative and quantitative assessment of enamel remineralization was performed using Scanning Electron Microscopy (SEM) and Energy Dispersive X-ray Spectroscopy (EDX). Results indicated a decline in Ca/P ratios post-demineralization across all groups, with GC Fuji Ortho LCTM showing the smallest reduction (0.29, p =0.0002). In contrast, 15% BAG exhibited the largest decline (1.11, p = 0.0001). Although there was a statistically significant increase in Ca/P ratio for the 15%BAG group post-pH cycling (-0.01, p = 0.0001), it remained significantly lower than baseline (1.103, p = 0.0001), indicating limited remineralization capability. Conversely, the 10% NHAp group demonstrated the most significant increase in Ca/P ratio post pH-cycling (-0.27, p = 0.0001) and no significant difference compared to baseline (-0.05, p = 1.0000), highlighting its superior ability to remineralize enamel. SEM imaging revealed the formation of an apatite-like layer on enamel treated with 10% NHAp, suggesting its potential for enhanced enamel protection and ion reservoir properties. This study underscores the potential of 10% nanohydroxyapatite as an effective agent for enamel remineralization in orthodontic applications, offering promising benefits over traditional and other bioceramic options. Dental enamel. Orthodontics. FI UPMNL DENT LG995 2024 D45 G85 Thesis