Effect of commercial herbal toothpastes and mouth rinses on the prevention of enamel demineralization using a microcosm biofilm model.

This work evaluated the effects of commercial toothpastes and mouth rinses containing natural/herbal agents on biofilm viability, extracellular polysaccharide (EPS) production and on enamel demineralization in vitro. Microcosm biofilm was produced on bovine enamel for 5 days and treated daily with: Orgânico natural® (toothpaste/mouth rinse), Boni Natural Menta & Malaleuca® (toothpaste/mouth rinse), Propolis & Myrrh® (toothpaste), Colgate Total 12 Clean Mint® (toothpaste, positive control), Malvatricin® Plus (mouth rinse), PerioGard® (mouth rinse, positive control) or PBS (negative control). Tom's Propolis & Myrrh® and Colgate Total 12® toothpastes and Malvatricin® Plus and PerioGard® mouth rinses significantly reduced biofilm viability (p < 0.05). Only PerioGard® had significant effects on biofilm thickness and EPS. Despite the indication that Tom's Propolis & Myrrh® significantly reduced lesion depth, only Colgate Total 12® significantly reduced mineral loss. Malvatricin® Plus significantly reduced mineral loss and lesion depth, as did PerioGard®. Some herbal products, Malvatricin® Plus and Tom's Propolis & Myrrh®, showed anticaries effects.

Can the Concentration of Citric Acid Affect Its Cytotoxicity and Antimicrobial Activity?

BACKGROUND: There has been no unanimity concerning the ideal concentration of citric acid for safe use in clinical practice. This study evaluated the cytotoxicity and the antibacterial activity in infected dentinal tubules of 10% and 1% citric acid (CA) solutions. METHODS: The cytotoxicity of CA solutions in DMEM (diluted 1/10, 1/100) was assessed in L-929 fibroblasts. A broth macrodilution method (MIC and MBC) was used to assess CA antibacterial concentration. The antimicrobial activity of CA solutions was also evaluated after their final rinse inside root canals in previously Enterococcus faecalis-contaminated dentinal tubules. Ten infected dentine samples were rinsed for 5 min with 5% NaOCl and subsequently with 1% citric acid for 3 min. Another 10 were rinsed with 5% NaOCl and 10% citric acid for 3 min; the remaining four specimens were utilized as positive controls. Two uncontaminated specimens were used as negative controls. After LIVE/DEAD BacLight staining, the samples were assessed using CLSM to analyze the percentage of residual live and dead cells. RESULTS: Both undiluted and diluted CA solutions showed severe toxicity; no changes from normal morphology were displayed when diluted 1/100. The MIC and MBC of CA were 6.25 mg/mL and 12.50 mg/mL, respectively. CA solutions demonstrated significantly low levels of bacterial counts than the positive control group, reporting a value of 9.3% for the 10% solution versus the 1% solution (35.2%). CONCLUSIONS: Despite its valuable antimicrobial properties, the cytotoxic effects of citric acid should be considered during endodontic treatment.