Optimum concentration and application time of 1,6-hexanediol as a dentin primer.
The optimum concentration and application time for an experimental dentin primer composed of an aqueous solution of 1,6-hexanediol were determined by measuring the wall-to-wall polymerization contraction gap width of a commercial light-activated resin composite in a cylindrical dentin cavity prepared in an extracted human molar. Contraction gap formation was completely prevented only when the dentin cavity wall was primed with 45 wt% 1,6-hexanediol for 60 s. There were no significant differences in tensile bond strength among primers composed of 20.0-57.5 wt% 1,6-hexanediol. These results suggest that the optimum concentration and application time are 45 wt% and 60 s, respectively.
Bonding efficacy and interfacial microstructure between resin and dentine primed with glyceryl methacrylate.
OBJECTIVES
To evaluate the effect of two experimental primers based on glyceryl methacrylate (GM, 2,3-dihydroxypropyl methacrylate) and 2-hydroxyethyl methacrylate (2-HEMA) on the marginal adaptation of light-cured composite placed into cylindrical dentine cavities and to study the interfacial microstructure.


METHODS
The bonding efficacy of two experimental dentine primers combined with a dentine cleanser composed of either 0.5 mol l-1 EDTA neutralized to pH 7.4 by sodium hydroxide or 10% citric acid containing 3% ferric chloride (10-3 solution), and a commercial dentine bonding agent containing phosphate ester, were examined by measuring the wall-to-wall polymerization contraction gap of a commercial light-activated resin composite placed into cylindrical dentine cavities. The adhesive interface between the dentine and the dentine adhesive was observed using a transmission electron microscope (TEM).


RESULTS
The formation of a contraction gap was completely prevented by priming with GM, regardless of the dentine cleanser used. However, in groups primed with 2-HEMA, gap formation was observed in three and four specimens out of 10 in the groups that were cleaned with the EDTA and 10-3 solution, respectively. In samples primed with GM, a high-density layer was observed by TEM at the superficial dentine in the hybrid layer, which may have indicated a high monomer content, whereas no density variations were observed in the hybrid layer in samples primed with 2-HEMA.
Kant's 'Religion within the Boundaries of Mere Reason'
Preface 1. Context 2. Overview of Themes 3. Reading the Text Prefaces to the First and Second Editions Part I of the Religion Part II of the Religion Part III of the Religion Part IV of the Religion 4. Reception and Influence 5. Guide for Further Reading Bibliography Index