Abbasi, Aliza Anwaar creator Supervisor: Dr. Sabah Javaid text monographic 64p. Soft Copy 30cm Aliza Anwaar Abbasi Secondary caries rests as the most important challenge in resin-based dental composites, encouraging search of bioactive fillers like silanized hydroxyapatites and fluorides to increase antibacterial performance without negotiating mechanical integrity. This study developed and verified novel UDMA-based composites: a control with camphorquinone photoinitiator, whereas the experimental group integrating APTES-silanized hydroxyapatite plus calcium fluoride. Antibacterial efficacy was evaluated via disk diffusion assays against Staphylococcus aureus and Escherichia coli, revealing clear zones of inhibition nearby experimental disks greater than controls representing fluoride-driven disruption of bacterial growth. Wide-ranging characterization, including SEM, FTIR, EDX analysis, water absorption and solubility done by the use of artificial saliva confirmed efficacious synthesis, structural integrity, and the existence of preferred functional groups. Outcomes highlight these formulations potential to limit oral biofilms and improve restorative durability, with silanization helping filler dispersion and ion release; future work should measure mechanical properties and continuing fluoride kinetics for medical translation. MS Biomedical Sciences (BMS) 610 http://10.250.8.41:8080/xmlui/handle/123456789/57400 http://10.250.8.41:8080/xmlui/handle/123456789/57400