Synthesis And Characterization Of Antibacterial Dental Composite

Dental composite was synthesized by a mixture of matrix resin,inorganic filler and initiator. Since bisphenol A-biglycidyl methacrylate (Bis-GMA) was synthesized in 1960s, it was used widely in dental composites. But the gap between remedy and tooth and the bacterium growing on tooth caused econdary caries and damage of dental pulp. So that dental remedy with antibacterial property has a bright future.This paper used Bis-GMA and TEGDMA as the resin matrix, nanometer SiO2 as the inorganic filler. Reactive carbon-carbon double bonds were introduced to the molecular structure of polyhexamethylene guanidine (PHMG) by condensed with glycidyl methacrylate (GMA). Then the composite was cured by chemical and ultraviolet curing. Antibacterial properties and mechanical properties were tested. The curing degree was researched.PHMG was modified by GMA and maleic anhydride (MAH) respectively. The structure and reaction degree of the products were tested through FT-IR and 1H-NMR. The results showed that PHMG could be modified by both MAH and GMA. PHMG modified by GMA was in favor of generating dental composite, so that PHMG-GMA was adopted to generate dental composite in this paper.PHMG-GMA,Bis-GMA,TEGDMA,SiO2 and initiator were mixed in proportion.Then the mixture was cured. Research on the composite initiated by AIBN showed that PHMG-GMA wouldn't affect mechanical property. SiO2 would cause decrease of bending strength but it would increase compressive strength and rock-well hardness. When the mass fraction of PHMG-GMA was 1%, the antibacterial rate against streptococcus mutans reached 99.99%. Antibacterial composite could also be genereated by CQ and its antibacterial rate against E coli reached 99.0%.