| Budget Amount *help |
¥2,400,000 (Direct Cost: ¥2,400,000)
Fiscal Year 1996: ¥500,000 (Direct Cost: ¥500,000)
Fiscal Year 1995: ¥1,900,000 (Direct Cost: ¥1,900,000)
|
|---|
| Research Abstract |
Polymeric phosphonium salt was studied to develop antimicrobial dental resin. Phosphonium salt monomer was tributyl (4-vinylbenzyl)-phosphonium chloride (V), and acrylic acid (A) and methacryloyloxyethyl-trimethylammonium chloride (M) were used as control. Antimicrobial activity of those monomers and the corresponding polymers (PA,PM,PV) to Streptococcus mutans Ingbritt were examined. The degree of antimicrobial activity of A,PA and PM was lessthat of PM and V were some little, and that or PV was good.
The V or M was dissolved in the mixed monomer of methyl methacrylate and 2-hydroxyethyl methacrylate at 8 : 2 molar ratio The monomer mixtures were cured with benzoyl peroxide in a glass tube. The content of V and M in the copolymer was 1,2 and 3mole% for V and 1mole% for M (The abbreviation of the copolymers : CV1, CV2, CV3 and CM1, respectively, and that of the copolymer without V and M : C). The cured copolymers with dimensions of 10mm in diameter and 1mm in thickness were immersed in a medium containing Streptococcus mutans Ingbritt and incubated anaerobically for 24hours at 37ﾟC.The amount of accumulated bacteria on the copolymer was determined with an optical densitometer. The amount of adhered bacteria on CV1, CV2 and CV3 was significantly less than those of C and M.
The compressive and bending strengths of those copolymers decreased with a increase of the monomer in the copolymer, for example, the compressive and bending strength fo CV1 and CM1 were about 10% and 20% less, respectively, than those of C.
|
