The clinical and microbiological efficacy of a zinc-citrate/hydroxyapatite/potassium-citrate containing toothpaste: a double-blind randomized controlled clinical trial.

Objectives: To evaluate the antibacterial efficacy of two fluoride-containing (1450 ppm F) toothpastes with or without zinc-citrate (ZCT), hydroxyapatite (HAP) and potassium-citrate (KCit); to assess and compare their clinical effects in terms of tooth sensitivity, plaque accumulation and gingivitis, as well as patients' satisfaction.

Materials and methods: Healthy, adult patients were selected and randomly assigned to two groups (n = 50): Experimental: ZCT-, HAP-, KCit- and fluoride-containing toothpaste; Control: fluoride-containing toothpaste. Salivary counts of Streptococcus mutans (S. mutans), plaque and gingival index, as well as clinically diagnosed sensitivity were recorded at baseline, and after 4 weeks. A custom-made questionnaire was used to assess patients' self-reported sensitivity (baseline and after 4 weeks) and overall satisfaction with the tested toothpastes. Data were statistically analyzed (α = 0.05).

Results: After 4 weeks, a statistically significant salivary reduction of S. mutans was observed in both groups (p = 0.001). Furthermore, the percentage of S. mutans decrease was significantly higher in Experimental group (p = 0.014). There were no statistically significant differences between the groups in terms of plaque and gingival index (p > 0.05). After 4 weeks, the self-reported tooth sensitivity was lower in Experimental group (p < 0.001).

Conclusions: Both toothpastes showed good antimicrobial effect after 4 weeks; however, the toothpaste containing ZCT, HAP, KCit and fluoride was found to be more effective in reducing the salivary counts of S. mutans than the product containing fluoride alone.

Clinical relevance: Toothpaste containing ZCT, HAP, KCit and fluoride can be recommended for patients at risk for developing caries and may also be beneficial for individuals experiencing dental sensitivity.