Arif, Wafa creator Supervisor : Dr. Nosheen Fatima Rana text monographic 68p. Soft Copy 30cm Wafa Arif Resin composites have been widely used in dental restoration. However, polymerization shrinkage and resultant bacterial microleakage is a major limitationthat may leads to secondary caries. To overcome this, a new type of antibacterial resincomposites containing ciprofloxacin loaded silver nanoparticles were synthesized. Ciprofloxacin loaded silver nanoparticles were successfully synthesized withchemical reduction method which was confirmed by Ultraviolet–visible (UV-Vis) spectroscopy, Scanning Electron Microscopy (SEM), Fourier-transforminfraredspectroscopy (FTIR) and Zeta potential. Ciprofloxacin loaded silver nanoparticles were added into resin composites. The antibacterial properties of these ciprofloxacinloaded silver nanoparticles modified resin composites against Enterococcus faecalis, Streptococcus mutans and Saliva Microcosm model were evaluated. Cytotoxicityof these modified resin composites was determined by performing hemolytic assay. Compressive strength (CS) of these modified resin composites was assessed byauniversal testing machine. The results indicated that the antibacterial activityandcompressive strength of resin composites containing Ciprofloxacin loaded silver nanoparticles were superior to the control group and also exhibited less cytotoxicityas compared to the resin composites containing silver nanoparticles. In short, theseresults established strong ground applications for CIP-AgNPs modified dental composite resins. MS Biomedical Engineering (BME) 610 http://10.250.8.41:8080/xmlui/handle/123456789/30725 http://10.250.8.41:8080/xmlui/handle/123456789/30725