The purpose of this study were to examine the effect of 4-META/MMA-TBB resin containing calcium chloride dihydrate (CaCl2) on dentin remineralization and its mechanical properties. Different percentages of CaCl2 (5%, 10%, and 30%) were added to 4-META/MMA-TBB resin. The Ca2+ released from CaCl2 bound to the phosphoprotein formed hydroxyapatite crystals to initiate dentin remineralization in 5%, 10% and 30% CaCl2 groups in vitro dentin mineralization system. Mineral induction time decreased with increasing of CaCl2 concentration in the resin. Vickers hardness and bending strength of 5% CaCl2 group were significantly higher than other groups. The results of elasticity analysis for the control, 5% and 10% CaCl2 groups showed no significant difference, and the viscosity analysis showed no significant difference between 4-META/MMA-TBB resin with up to 10% CaCl2 and the control.
The 4-META/MMA-TBB resin with 5% CaCl2 showed dentin remineralization activity with good mechanical properties.
The purpose of this study was to evaluate the effects of direct pulp capping on hard tissue formation by using alginate gel (AG) containing bone morphogenetic protein-2 (BMP2). Cavities with the exposed pulp areas were prepared on Wistar rats molars and were covered with AG containing BMP-2. Experimental sites were divided into two groups according to whether or not BMP-2 (0.1 µg/µL) was contained in AG. Then they were sealed with 4-META/MMA-TBB resin cement. In both groups, the covered materials were observed at one week after operation. At four weeks, they had disappeared, and the hard tissue formation was observed. Thickness of the hard tissue formation of AG containing BMP-2 group was significantly higher than that of AG without BMP-2 group (P < 0.05). These results suggest that AG containing BMP-2 has effects on hard tissue formation in the case of direct pulp capping.