Antibacterial activities and bonding of MMSA/TBB resin containing amphiphilic lipids.

The purpose of this study was to investigate the antibacterial activity of MMA/TBB resin containing newly developed amphiphilic lipids. The amphiphilic lipids, C10-L-Ala/pts and C12-L-Ala/pts, synthesized from the reaction of n-alkyl alcohol and L-alanine were dissolved in MMA at concentrations of 0.5, 1.0, 1.5, and 2.0 mol%. Resin mixtures of PMMA powder and each MMA liquid containing lipid and TBB were prepared for all tests. Both lipids gave antibacterial effect to MMA/ TBB resin. The addition of C12-L-Ala/pts to MMA resulted in a significantly higher antibacterial activity than the addition of C10-L-Ala/pts. In terms of bond strength, the bond strength of MMA/TBB resin to bovine dentin was significantly decreased by the addition of amphiphilic lipids. But for enamel, the bond strength of MMA/TBB resin with amphiphilic lipids was clinically acceptable for orthodontic brackets. In conclusion, amphiphilic lipids will be useful as a component of adhesive resin to give the latter an antibacterial effect.