|Budget Amount *help
¥3,300,000 (Direct Cost : ¥3,300,000)
Fiscal Year 2000 : ¥700,000 (Direct Cost : ¥700,000)
Fiscal Year 1999 : ¥600,000 (Direct Cost : ¥600,000)
Fiscal Year 1998 : ¥700,000 (Direct Cost : ¥700,000)
Fiscal Year 1997 : ¥1,300,000 (Direct Cost : ¥1,300,000)
The cause of the plaque accumulation is attributed to the attachment of microorganisms to the solid surface brought about by physicochemical interactions. Silane coupling agents containing fluorocarbon chains have several characteristics such as water and oil repellency, prevention of contamination, high lubricity, and thermal and chemical stability. Yoshino et al. synthesized two dental silane coupling agents named 1H, 1H, 2H, 2H-henicosafluorododecyltriisocyanatosilane (10F2S-3I) and 1H, 1H, 2H, 2H-henicosafluorododecyltrimethoxysilane (10F2S-3M). The surface modification of resin composite with 10F2S-3I or 10F2S-3M has shown a preventive effect on the initial adherence of bacteria to composite surface. In the present experiment, the surface modification efficacy of 10F2S-3I was evaluated on the enamel surface.
The bovine teeth specimens were cut and smoothly finished. The specimens were divided into three groups : 1) control group without treatment, 2) surface modified group (MG) : a
pplied 30.0mmol/l of 10F2S-3M or dodecyltrimethoxysilane (10H2S-3M), or 3.0mmol/l of 10F2S-3I, and 3) pretreated and surface modified group (PMG) : applied each silane after etching with phosphoric acid (PMG). Surface free energy, the amount of calcium dissolution, accumulation of Streptococcus mutans in vitro, and accumulation of plaque in vivo were evaluated in each group of specimens. The hydroxyapatite powder (HAP) and bovine enamel powder (BEP) were also treated with each silane, and amount of adsorbed phosvitin was determined by gel permeation chromatography. The data were analyzed statistically using ANOVA and Fisher PLSD at p<0.05.
The surface free energy of MG and PMG modified with 10F2S-3I or 10F2S-3M were significantly lower compared with control. The amount of phosvitin adsorption onto both HAP and BEP treated with 10F2S-3I or 10F2S-3M were significantly less than these of controls. The amount of calcium dissolution from MG and PMG after 60 minutes was significantly less than those of control. The total amount of S.mutans accumulated on MG and PMG modified with 10F2S-3I were significantly less than that of control. The total amounts of plaque accumulated on MG and PMG modified with 10F2S-3I using intra oral plaque accumulation test appliance were significantly less than compared with control after 7 days. There were no significant difference was found between the MG and PMG on the amount of plaque accumulation.
From the results obtained in this study, it was suggested that the surface modifier 10F2S-3I significantly reduce plaque adherence to enamel. In conclusion, the use of 10F2S-3I may have clinical contribution to maintenance of oral health. Less