Alkali ion substituted calcium phosphate cement formation from mechanically activated reactants.

Area of Science:

• Biomaterials Science
• Materials Chemistry
• Dental Materials

Background:

• Nanoapatite cements are crucial in regenerative medicine and dentistry.
• Developing cements with enhanced properties like solubility and antimicrobial activity is an ongoing research area.
• The synthesis and characterization of novel cement formulations are essential for clinical advancements.

Purpose of the Study:

• To produce potassium and sodium-containing nanoapatite cements using mechanical activation.
• To investigate the effects of high energy ball milling on the physical and chemical properties of the cement precursor.
• To evaluate the setting time, compressive strength, and pH of the synthesized cements for potential dental and orthopedic applications.

Main Methods:

• Ca2KNa(PO4)2 was subjected to prolonged high energy ball milling for up to 24 hours.
• X-ray diffraction (XRD) and differential scanning calorimetry (DSC) were used to analyze structural changes.
• The pH of water-saturated samples was measured, and setting times and compressive strengths were determined after mixing with a 2.5% Na2HPO4 solution.

Main Results:

• Mechanical activation led to decreased crystal size and partial amorphisation of Ca2KNa(PO4)2.
• Milled material showed a significantly increased pH (12.5) and enhanced solubility compared to untreated compound (pH 9.5).
• Cements set within 5-12 minutes and achieved compressive strengths up to 11 MPa after 24 hours.

Conclusions:

• High energy ball milling is an effective method to produce nanoapatite cements with desirable properties.
• The resulting cements possess a highly alkaline pH and good mechanical strength, suitable for dental applications.
• The antimicrobial potential due to high alkalinity suggests use as pulp capping agents, cavity liners, or for treating infected bone.