DEVELOPMENT OF SOME CALCIUM-PHOSPHATE CEMENTS FROM COMBINATIONS OF ALPHA-TCP, MCPM AND CAO

From previous studies it is known that alpha-tertiary calcium phosphat e (alpha-TCP), monocalcium phosphate monohydrate (MCPM) and calcium ox ide form cements upon mixing combinations of them with water. In this study some formulations were optimized with respect to the particle si ze of the constituents, their molar ratio, amounts of hydroxyapatite o r beta-tertiary calcium phosphate (beta-TCP) added and the water/powde r ratio. Three suitable products were obtained. Product 1 had a relati vely short setting time and might be suitable as a dental cavity liner or for filling parodontological pockets or for filling alveolar cavit ies to prevent alveolar ridge resorption. Products 2 and 3 may be more suitable for orthopaedic purposes. Their compressive strength being 3 5 and 12 MPa, respectively, after soaking for 1 day in Ringer's soluti on at 37-degrees-C. Product 1 reaches its full strength within 4 h, wh ereas products 2 and 3 take about 12 h and 10 h, respectively.