Influence of β-tricalcium phosphate of different geometric shape on the morphology of regeneration of experimental defect of compact bone tissue

Abstract

Purpose: to compare the healing process of a defect of compact bone tissue after the implantation of osteoplastic materials based on β-tricalcium phosphate ("ChronOS" and "Calc-i-oss®"), which differ by manufacturer, geometrical shape and microscopic structure. Methods: the experiment was performed on 48 white male Wistar rats. In the middle third of the diaphysis of the femur we produced a perforated defect of 2.5 mm diameter in the medullary canal, which in the animals of the first group was filled with the osteoplastic material "ChronOS" (block, Synthes, Switzerland), and in the animals of the second group - with "Calc-i-oss®" (granules, «Degradable Solutions Dental», Switzerland). Fragments of the injured bones were studied on the 60th and 120th day by light microscopy with morphometry and by scanning electron microscopy. Results: it was found that regardless the geometric shape and the microscopic structure, both osteoplastic materials show high biocompatibility, osteoconductive properties, good integration with bone tissue of the regenerate, and that the microscopic structure of β-tricalcium phosphate ("ChronOS") may significantly affect the microscopic structure of bone tissue of the regenerate, which manifests itself in the specificity of its geometric shape. It was noticed that osteoplastic materials "ChronOS" and "Calc-i-oss®" almost at the same rate were subjected to resorption and replacement by the bone tissue, the ratio of which on the 60th day of the experiment was 22.55±1.25 to 77.45±1.25 and 25.72±2.06% to 74.28±2.06%, and on the 120th day 17.65±1.09 to 82.35±1.09 and 18.31±1.54% to 81.69±1.54%.