If impression materials could be immersed in disinfectant solutions for a longer period, then this form of disinfection would be easier to incorporate into dental preparation procedures. This study investigated the dimensional changes in stone models resulting from immersion of medium-viscosity hydrophilic addition-type silicone rubber impression material in disinfectant solutions for 30 min and 24 h. Impressions of a master die designed to simulate a full crown preparation with adjacent teeth were immersed in 2% glutaraldehyde and 0.
View Article and Find Full Text PDFThis study investigated the effects of immersion of addition silicone rubber impressions in disinfectant solutions on the surface porosity of the resulting stone casts. Five brands of type 2 and 3 addition silicone rubber impression materials and one brand of type 4 dental stone were used. Impressions of a master die designed to simulate an abutment tooth were immersed in disinfectant for 30 minutes.
View Article and Find Full Text PDFThere is a concern that long-term immersion of impressions in disinfectant solutions may cause changes in the dimensions of the resulting stone casts. This study investigated the dimensional changes in stone casts resulting from immersion of five brands of addition-type silicone rubber impressions in disinfectant solutions for 30 min and 24 h. Impressions of a master cast designed to simulate an abutment tooth were immersed in 2% glutaraldehyde and 0.
View Article and Find Full Text PDFThis study investigated the effect of the immersion of alginate impressions in 0.5% sodium hypochlorite solution for 15 min on the dimensional changes of stone models designed to simulate a sectional form of a residual ridge. Five brands of alginate impression materials, which underwent various dimensional changes in water, were used.
View Article and Find Full Text PDFUsing tensile tests, this study investigated differences in the welding strength of casts of cobalt-chromium and gold alloys resulting from changes in the voltage and pulse duration in order to clarify the optimum conditions of laser irradiation for achieving favorable welding strength. Laser irradiation was performed at voltages of 150 V and 170 V with pulse durations of 4, 8, and 12 ms. For cobalt-chromium and gold alloys, it was found that a good welding strength could be achieved using a voltage of 170 V, a pulse duration of 8 ms, and a spot diameter of 0.
View Article and Find Full Text PDFThis study was carried out to examine the effect of storage conditions of adhesive vials on the dentin bond strength of single-step self-etch adhesive systems. The adhesive/resin composite combinations used were: Absolute 2/Ceram.X(AB), Adper Prompt L-Pop/Filtek Supreme(AP), Bond Force/Estelite sigma Quick(BF), Clearfil tri-S Bond/Clearfil AP-X(CT) and G-Bond/Gradia Direct(GB).
View Article and Find Full Text PDFThis study investigated the effects of storing impressions for 3 hours after spraying them with a disinfectant solution on dimensional change and deformation of maxillary edentulous stone models. Three brands of alginate impression materials, characterized by a small degree of contraction in 100% relative humidity, were used. The spray disinfectants used were 1% sodium hypochlorite solution and 2% glutaraldehyde solution.
View Article and Find Full Text PDFThis study investigated the effects of disinfection of combined agar/alginate impressions on the dimensional accuracy of resultant stone casts. Impressions of a master cast designed to simulate an abutment tooth were prepared by combining each of two brands of cartridge-form agar impression materials with an alginate impression material. The impressions were immersed in 1% sodium hypochlorite for 10 minutes or 2% glutaraldehyde for 30 minutes.
View Article and Find Full Text PDFWe studied the thermal properties of cavity liners that included calcium phosphate as inorganic filler, in contrast to the conventional pulp capping agents. Therefore, thermal diffusivity, specific heat capacity, and thermal conductivity were measured. In addition, thermal conductivity results were compared with those of restorative materials and human dentin to examine thermal insulation effects.
View Article and Find Full Text PDFThe objective of this study was to synthesize a hybrid type filler composed of an organic component with inorganic component at the molecular level and to examine the properties of the filler. The composite resin was prepared by mixing synthesized filler with monomer and its physical properties were also examined. An organic-inorganic hybrid filler was synthesized by using 3-methacryloxypropyltrimethoxysilane (3-MPTS), methyltriethyoxysilane (MTES) and methanol silica sol.
View Article and Find Full Text PDF