Injectable and rapid-setting calcium phosphate bone cement with dicalcium phosphate dihydrate

Area of Science:

• Biomaterials Science
• Orthopedic Surgery
• Dental Materials

Background:

• Calcium phosphate cement (CPC) mimics bone and tooth mineral (hydroxyapatite) and adapts to defect sites.
• Existing CPCs require improvement in setting time and delivery method for clinical applications.

Purpose of the Study:

• To develop an injectable and rapidly setting calcium phosphate cement (CPC) utilizing dicalcium phosphate dihydrate (DCPD).

Main Methods:

• Incorporated sodium phosphate as a hardening accelerator and hydroxypropyl methylcellulose (HPMC) as a gelling agent.
• Evaluated setting times and paste injectability of the developed cement (CPC(D)) compared to a conventional cement (CPC(A)).
• Assessed flexural strength and elastic modulus of the injectable CPC(D).

Main Results:

• CPC(D) demonstrated significantly faster setting times (17 ± 1 min) compared to CPC(A) (82 ± 6 min).
• HPMC addition dramatically improved injectability for both CPC(D) (98% ± 1%) and CPC(A) (99% ± 1%).
• CPC(D) exhibited mechanical properties comparable to hydroxyapatite implants and cancellous bone.

Conclusions:

• The injectable and rapid-setting CPC(D) provides quick graft strength and stability.
• Its injectability is advantageous for precise placement in difficult-to-access bone defects and minimally invasive procedures.