The effect of phase formation on biomechanical and biological performance of Li2O-Al2O3-SiO2 glass-ceramics

Lithium aluminum silicate (LAS, Li2O-Al2O3-SiO2) glass-ceramics have been employed in dentistry as substitutes while seldom in orthopaedics. This is primarily due to difficulties with balancing the biomechanical and biological performance. This study aims to investigate the effects of SiO2 content and thermal treatment on the formation of Li2SiO3, Li2Si2O5 and LiAlSi2O6 in LAS glass-ceramics, and the effects of these crystalline phases on the biomechanical and biological performance. The preparation of LAS glass-ceramics were divided into two stages. In the first step, six components (C1, C2, C21, C22, C23 and C3) of LAS glass-ceramics were prepared and characterized. In the second step, the CN1, CN2 and CN3 with the principal phases of Li2SiO3, Li2Si2O5 and LiAlSi(2)O(6 )were obtained based on the C1, C22 and C3 and evaluated in biomechanics and biology. With the content of SiO2 increasing from 65.11% to 67.96%, the formation of Li2Si2O5 and LiAlSi2O6 correspondently increased. The extension of the holding time at 850 C promoted the generation of LiAlSi2O6 at the expense of Li2Si2O5. The main crystalline phase coupled with Li2Si2O5 and LiAlSi2O6 (dominated by LiAlSi2O6) resulted in a high flexural strength of 378 & PLUSMN; 29 MPa and favorable cell viability of 115.21 & PLUSMN; 14.63%. The impressive biomechanical and biological results of CN3 indicate that this glass-ceramic may be a good candidate for orthopaedic applications.