Abstract:

Objective To investigate the antibacterial property of polyurethane based material containing polyphosphazenes nanosphere. Methods Test specimens made of polyurethane (PU group), polyurethane containing 1% polyphosphazenes nanosphere (1% PSZ group), polyurethane containing 5% polyphosphazenes nanosphere (5% PSZ group), selfcuring silicon rubber material (negative group) and inner flat of sterilized plate (blank control group) were prepared (n=30). The antibacterial property for Candida albicans, Staphylococcus aureus and Escherichia coli of test specimens in each group was tested. The colonies were counted by sticking membrane culture method, and the antibacterial rates were calculated. Material with antibacterial rate lower than 90% was regarded as having no antibacterial property. Results The antibacterial rates of test specimens in PU group, 1% PSZ group and 5% PSZ group for Candida albicans were 5.60%, 3.75% and 6.25% respectively, those for Staphylococcus aureus were －2.31%, 1.63% and 12.80% respectively, and those for Escherichia coli were 8.65%, 0.75% and 6.02% respectively. Conclusion Polyurethane based soft liner materials containing less than 5% polyphosphazenes nanosphere have no significant effect on oral microflora balance.

Key words: polyurethane, polyphosphazenes, antibacterial property, soft liner material