The Study Of Fluoride Thermoplastic Resin Preventing Dental Carie In Abutment Teeth Of Removable Partial Dentures In Vitro

Objective To explore the effect of the topical-fluoride denture base in preventing dental caries of abutment teeth. Methods 10 non-carious human teeth were cut into 20 specimens, 2~3mm enamel.With paired designed ,they were devided into two groups and each group had 10 specimensds.The test group was contacted with fluoride thermoplastic resin; the control group was contacted with non-fluoride thermoplastic resin.They were rinsed by continuous artificial saliva in simple artificial mouth. The fluoride concentration of artificial saliva was detected every weekend . The surface microhardness was measured after four weeks..Then the specimens were demineralized, the artificial caries were diagnosed with a laser fluorescence systen. Results 1. The fluoride concentration of test group was 0.050±0.0044ppm in the first weekend,0.057±0.0031ppm in the seconds weekend, 0.046±0.0043ppm in the third weekend, 0.043±0.0024ppm in the fourth weekend; the control group was 0.055±0.0016ppm, 0.048±0.0088ppm,0.043±0.0015ppm,0.040±0.0027ppm in the first,second,third and fourth weekends respectively.They was no significant difference between two groups(p>0.1).2. The surface microhardness of the test group was 298.02±24.30kg/mm2; that of the control group was 274.26±22.14kg/mm2. The surfac microhardness of 8 specimens of the test group were higher than that of control group and 2 of them were lower than that of control. The surfac microhardness of the test group significantly higher than that of the control group(P<0.05). 3. The depth of artificial carie was 5.15±1.43 in the test group and 6.2±1.32 in the control group.The depth of artificial carie of 7 specimens of the test group were lower than that of control group,2 of them were as deep as that of control group,1 of them was deeper than that of control group. The depth of artificial carie of the test group was significantly lower than that of the control group(P<0.05). Conclusions The Fluoride thermoplastic resin may not significant raise the fluoride concentration in artificial saliva,but it can significantly raise the enamel surface microhardness and the acid resistance of the specimen. The Fluoride thermoplastic resin had play an important role in preventing dental carie of abutment teeth.