The use of oxymetazoline-based nasal solutions to remove bacteria-blood debris and eradicate Rothia dentocariosa: an artificial cavity model study.

BACKGROUND: This study evaluated the antibacterial properties of a potential pulpal medicament, a nasal solution with oxymetazoline (NS-OXY, 0.05%), against a dentinal caries pathogen. METHODS: Using a disc diffusion susceptibility test (n = 6), Rothia dentocariosa was grown on brain-heart infusion (BHI) agar plates and exposed to OXY (0.05%), benzalkonium chloride (BKC-0.025%), OXY-NS (with OXY-0.05% and BKC), ferric sulfate (20%; ViscoStat), and distilled water (DI). This was followed by exposure of an artificial dental caries model with sheep blood to simulate the clinical pulpotomy procedure. An antibacterial broth inhibition test was conducted by adding the test samples in BHI broth at 37 ± 0.5 °C in an aerobic chamber. RESULTS: In the disc diffusion test, NS-OXY and BKC had the largest zone of inhibition (ZOI) measuring 14.42 mm (± 1.62) and 18.92 mm (± 4.14) respectively, indicating antibacterial activity. Ferric sulfate demonstrated a smaller ZOI, while OXY alone had no ZOI. The antibacterial broth test showed antibacterial effects with stable OD and pH levels for test samples containing BKC (0.025%) and diluted NS-OXY (0.01%) for up to 20 h. DI- and OXY-treated samples showed an increase in OD, indicating an increase in bacterial count and a concurrent drop in pH. BKC treatment statistically (P < 0.05) reduced polyP extracts, which may contribute to blood clot formation. NS-OXY demonstrated antibacterial properties, likely due to the addition of BKC to Rothia dentocariosa. NS-OXY showed concentration dependent biocompatibility with dental pulp stem cells while FS was cytotoxic at the same dilution. CONCLUSION: These antimicrobial properties, together with OXY's hemostatic effects, suggest the potential off-label use of NS-OXY during a pulpotomy procedure in primary and permanent teeth. This study provides support for potential future clinical trials of repurposing FDA-approved drugs consisting of oxymetazoline and benzalkonium chloride for dental and other similar applications. FEATURED APPLICATION: An over-the-counter nasal solution containing oxymetazoline has the potential to be used off-label to manage surgical bleeding from dental pulp exposures and provide antimicrobial properties against Rothia dentocariosa, a model gram-positive bacteria associated with deep dentinal caries.