PHYSICAL AND CHEMICAL CHARACTERIZATIONS OF SELF-ETCHING AND SELF-ADHESIVE EXPERIMENTAL CALCIUM-BASED CEMENTS
Pulp Capping. Cements. Calcium Hydroxide. Calcium Chloride. UltraBlend-Plus.
The aim of this study was to evaluate the Degree of Conversion (DC), Calcium Release (CR), Flexural Strength (FS), Elastic Modulus (ME), Viscosity (VS) and Bond Strength (BS)of experimentally calcium based cements self-etching and self-adhesive. Three experimental cements: A (CONTROL), B (HYDROCAL), C (CLORECAL) were synthesized and evaluated together with a commercial cement D (ULTRAPLUS) (Ultra-Blend Plus®- South Jordan, Utah, USA). For the DC (n = 3), Fourier transform infrared spectroscopy (FTIR) was used. In determining the CR, samples (1.0mmx0.4mm) were used (n = 3) and reading through an atomic absorption spectrophotometer at 3, 24 and 72 hours. For FS/EM (n = 6), bar-shaped samples (7mmx2mmx1mm) were made and evaluated using a universal testing machine. For VS (n = 30), the variation in the strain rate was determined by a rotational concentric cylinder rheometer. For the BS, cylindrical samples fixed in bovine dentin (n = 10) were used. The shear bond strength test was carried out on a testing machine with a 50 N load cell, pulling the tooth/cement interface at a constant speed of 1 mm/min until the displacement occured. The RU was higher for experimental cements compared to commercial cement, while the GC was higher for A and B. The ME was higher for experimental cements, and the viscosity higher for cements containing calcium sources. Therefore, self-etching and self-adhesive cements containing calcium chloride may have satisfactory physical and chemical performance.