A review on the synthesis of β-TCP using different methods for biomedical applications

Beta-tricalcium phosphate (β-TCP) is widely utilized in biomedical applications due to its outstanding biocompatibility and strong osteoconductive properties. Its high bioresorbability in the physiological environment allows the implanted material to undergo slow, controlled degradation over time, facilitating a gradual replacement with the body's native tissue, making it particularly suitable for bone reconstruction. A large number of studies have investigated the synthesis of β-TCP using a variety of chemical approaches, including both dry and wet approaches. Each method has distinct advantages and limitations, and these significantly influence crystallite size, crystallinity, densification behavior, shrinkage, morphology, and the overall properties of the final product. For surgical implants that require high mechanical strength, achieving high ceramic density is essential. The use of nano-sized β-TCP powders as starting materials has proven effective in producing dense ceramics. Furthermore, to preserve the resorbability of β-TCP, it is critical to obtain a pure phase. For these reasons, investigations into β-TCP synthesis have steadily increased, with a particular focus on tailoring its crystallographic properties. This review focuses on six methods for synthesizing β-TCP for bone grafting materials, dental implant applications, and bone tissue engineering. Traditional β-TCP synthesis is often criticized for generating large, non-uniform particles and secondary phases at high temperatures. In contrast, methods such as sol-gel, hydrothermal, solution combustion, and chemical precipitation are preferred for their superior control over the final product properties. We summarize the available information on each synthesis process, including benefits and drawbacks.