Evaluation of physical-chemical properties and biocompatibility of a microrough and smooth bioactive glass particles.

The purpose of this study was to evaluate physical-chemical and biocompatibility characteristics of a simple synthesis and low cost experimental bioactive glass. Physical and chemical properties were analyzed using scanning electron microscopy (SEM), X-ray energy dispersive (EDX), X-ray fluorescence (XRF) and X-ray diffraction (XRD). The biomaterials were subcutaneously implanted into rats, according to the following groups: G1, PerioGlastrade mark; G2, Biograntrade mark, G3, Experimental Bioactive Glass U (BGU) and G4, Control (Sham). After 7, 15, 21, 45, and 60 days, 5 animals/group/period were sacrificed and the subcutaneous tissue was dissected for histological and histometric analysis, considering inflammatory reaction and granulation area, presence of polymorphonuclear (PMN), monuclear (MN) and fibroblast (F) cells. SEM analysis of biomaterials showed irregular particles with different surface characteristics. EDX showed calcium, oxygen, sodium, phosphorus and silicon; XRF revealed silica oxide (SiO(2)), sodium oxide (Na(2)O), calcium oxide (CaO) and phosphorus oxide (P(2)O(5)). XRD indicated non crystalline phase. Measurement of tissue reaction showed similar results among the experimental groups at 45 and 60 days. No difference was found for PMN, MN and F cell counts. All biomaterials exhibited partial resorption. In conclusion, the experimental bioactive glass analyzed showed physical and chemical characteristics similar to the commercially available biomaterials, and was considered biocompatible, being partially reabsorbed in the subcutaneous tissue.

Physico-chemical characterization and biocompatibility evaluation of hydroxyapatites.

The aim of this study was to evaluate the physico-chemical and biocompatibility characteristics of two different hydroxyapatites. Physical and chemical properties were analyzed using granulometric analysis, scanning electron microscopy (SEM), X-ray energy-dispersion (EDX), X-ray fuorescence (XRF) and X-ray diffraction (XRD). Biomaterials were implanted into the subcutaneous tissue on the dorsum of 36 Wistar rats, divided into the following groups: Group 1 - Gen-Ox (natural); Group 2 - HA-U (synthetic) and Group 3 - Control (Sham). After 15 and 30 days, 6 animals/period were sacrificed and the subcutaneous tissue was taken for histological and histometric analysis, giving consideration to inflammatory reaction and granule area. The granulometric test results showed a mean granule diameter of 161.6 microm (min = 19.0 microm; max = 498.0 microm) and 48.7 microm (min = 7.0 microm; max = 256.0 microm) for groups 1 and 2 respectively. Analysis with SEM demonstrated irregular and sharp-edge particles in group 1 (3332.8 +/- 274.3 microm(2)) and irregular and rounded particles in group 2 (1320.8 +/- 83.0 microm(2)) (P < 0.0001; Student's t test). EDX and XRF revealed calcium, carbon, oxygen, sodium and phosphorus in both groups. XRD indicated that both biomaterials were pure and crystalline. There was a statistically significant difference in granule area between the two groups after 15 days (P = 0.022; Student's t-test). After 15 days, an increased inflammatory response was seen in group 2 (P < 0.0001; ANOVA and Tukey's post hoc test) whereas it was more pronounced in group 1 after 30 days (P < 0.0001; ANOVA and Tukey's post hoc test). It was concluded that these biomaterials have similar physical, chemical and biocompatibility characteristics.