Objective: to investigate biofilm-inhibition effects of experimental and commercial antibacterial and fluoride-releasing sealants. Method: Four experimental sealants (EXP-1, EXP-2, EXP-3, EXP-4) and a control sealant were formulated with an antibacterial fluoride-releasing monomer (AFRM) (Xu, et al., J. Biomed. Mater. Res. B, 2012, 100B:1151-1162) and other dental monomers (BisGMA/UEDMA/HDDMA/HEMA=1/2/2/2) with total 65%monomers and 35%fillers. Exp-2 contains 10%NovaMin. Exp-3 and Exp-4 contain 5% and 10% 2-methacryloyloxyethyl phosphorylcholine (MPC), respectively. Fluoride-releasing commercial sealants Clinpro (3M ESPE, CL) and Fluroshield (Caulk/Dentsply, FS), and SeLECT Defense sealant (E34 Technologies) (E34), a non-fluoride antimicrobial sealant, were also included for comparison. Disc specimens (10x1mm (DxH), n=5) of the sealants were prepared and light cured (40s). To test the biofilm-inhibition effects, the UV-sterilized specimens were placed in 10 mL of BMGS biofilm medium inoculated with S. mutans (1:100) and incubated for 24 hrs. Then, the samples were removed, gently rinsed, and sonicated in 4 mL of medium. Each diluted medium was plated, and cultured on agar plates for 24 hours. The amount of S. mutans biofilms formation was determined by counting colony forming units (CFU). The contact angles of sealants were measured on the disc specimens with a Goniometer. The data were analyzed using ANOVA and Tukey HSD test.
Result: Table 1. Composition, biofilm CFU and contact angle of tested sealants (mean±SD).
Materials | AFRM, MPC (%) | S. mutans CFU | Contact Angle |
Control | - | (2.00±0.49)x107A | 79.12±0.23 |
CL | - | (2.51±0.14)x107A | 63.46±0.097 |
FS | - | (1.23±0.10)x107A | 79.12±0.23 |
E34 | - | (2.10±1.18)x107A | 65.76±0.05 |
Exp-1 | 16, 0 | (1.83±1.65)x105B | 76.51±0.50 |
Exp-2 | 16, 0 | (3.56±3.70)x105B | 66.18±0.25 |
Exp-3 | 15, 5 | (1.85±2.39)x106B | undetectable |
Exp-4 | 14, 10 | (1.11±1.53)x106B | undetectable |
Conclusion: All experimental sealants have shown significantly lower S. mutans CFU thus stronger biofilm-inhibition effects than control and commercial sealants (p<0.05). Adding 5% or 10% MPC drastically reduced contact angles but did not increase biofilm-inhibition effect.