Review on calcium- and magnesium-based silicates for bone tissue engineering applications.

Bone is a self-engineered structural component of the human body with multifaceted mechanical strength, which provides indomitable support to the effective functioning of the human body. It is indispensable to find a suitable biomaterial for substituting the bone as the bone substitute material requirement is very high due to the rate of bone fracture and infection lead to osteoporosis in human beings increases rapidly. It is not an easy task to design a material with good apatite deposition ability, a faster rate of dissolution, superior resorbability, high mechanical strength, and significant bactericidal activity. Since the synthetic hydroxyapatite was not able to achieve the dahlite phase of hydroxyapatite (natural bone mineral phase), silicates emerged as an alternate biomaterial to meet the need for bone graft substitutes. All silicates do not exhibit the properties required for bone graft substitutes, as their composition and methodology adopted for the synthesis are different. Calcium, magnesium, and silicon play a major role in the formation of bone mineral and their metabolism during bone formation. In this review, the relationship between composition and activity of calcium, magnesium-based silicates have been discussed along with the future scope of these materials for hard tissue engineering applications.