Abstract: Objective: To observe the antimicrobial properties of β-Ca₂SiO₃/CSH composite materials. Methods: Four cements were tested ,A(C_1.4Si),B(C_1.4Si/CSH₁₀),C(C_2.0Si) and D(C_2.0Si/CSH₁₀).Direct antimicrobial activity of the cements was tested by the agar diffusion for the streptococci mutans.The diameter of the bacterial inhibition zone was tested respectively.Antibacterial ratio of the cements was computed in different time period. Results: The average diameter of the bacterial inhibition zone of C or D was bigger than that of A or B. There were significant differences of the average diameter between C and A or D and A(P<0.05), the antibacterial ratio of C and D was up to 99% in 24h. Conclusion: The antimicrobial properties of β-Ca₂SiO₃/CSH complex were good.

Key words: β-Ca₂SiO₃ , α-gypsum S.mutans , Antimicrobial property