Characterization of dicalcium phosphate dihydrate cements prepared using a novel hydroxyapatite-based formulation

Area of Science:

• Biomaterials Science
• Dental Materials
• Calcium Phosphate Chemistry

Background:

• Dicalcium phosphate dihydrate (DCPD) cements commonly utilize beta-tricalcium phosphate (beta-TCP).
• Hydroxyapatite (HA) offers potential benefits like reduced acidity and tunable properties through ionic substitution.
• Investigating novel HA-based formulations is crucial for advancing cement technology.

Purpose of the Study:

• To characterize novel DCPD cements formulated with monocalcium phosphate monohydrate (MCPM) and HA.
• To assess the reactivity of both poorly and highly crystalline HA in the MCPM/HA system.
• To evaluate the setting properties, mechanical strength, and degradation behavior of these new cements.

Main Methods:

• Cements were prepared using a 4:1 molar ratio of MCPM to HA.
• DCPD formation was confirmed using both poorly and highly crystalline HA.
• Setting time, workability (with setting regulator), compressive strength, and in vitro degradation were evaluated.

Main Results:

• Rapid setting was observed in the MCPM/HA system, necessitating a setting regulator for workability.
• MCPM/HA cements exhibited compressive strengths comparable to established DCPD cements.
• Preliminary in vitro studies indicated a potentially faster DCPD to HA conversion rate in the MCPM/HA system compared to beta-TCP based cements.

Conclusions:

• Novel DCPD cements can be successfully prepared using MCPM and HA.
• The rapid degradation observed warrants further investigation for potential clinical applications.
• HA-based DCPD cements present a promising alternative with unique properties for further development.