Effect of desensitising paste containing 8% arginine and calcium carbonate on biofilm formation of Streptococcus mutans in vitro.

OBJECTIVES: To evaluate the influence of desensitising paste containing 8% arginine and calcium carbonate (Ar-Ca) on biofilm formation on dentine.

METHODS: Dentine discs were cut from extracted third molars and divided into the following three groups: no treatment, pumice treatment and Ar-Ca treatment. Surface topography and roughness were examined using scanning electron microscopy (SEM) and non-contact 3D surface profiler. After sterilisation, samples were incubated with Streptococcus mutans (S. mutans) for 4 h, 24 h and 72 h. Bacterial adhesion and biofilm formation were analysed using SEM, whereas MTT and lactic acid production assays were used to analyse the metabolic activity of S. mutans.

RESULTS: After polishing with either pumice or Ar-Ca, the surfaces of the samples became smoother than in the control group. The Ra values of the three experimental groups decreased significantly to 0.43 μm, 0.3 μm and 0.26 μm, respectively. Compared to the control group, fewer bacteria adhered to the dentine surface in the Ar-Ca group, while biofilm thickness decreased significantly for both groups after incubating for 24 h and 72 h. MTT and lactic acid production levers also showed a significant reduction in the Ar-Ca group.

CONCLUSIONS: Ar-Ca appears to present antibiofilm efficacy and may provide a promising approach to combat bacterial infection in hypersensitive dentinal lesions.

CLINICAL SIGNIFICANCE: As a clinical application of desensitising polishing paste, the paste containing 8% arginine and calcium carbonate could also inhibit the biofilm formation effectively.