Evaluation of the Efficacy of a Dentifrice Tablet to Prevent Dental Caries: A Microbial Study

Published In: Dentistry Journal (Dent. J.)
Publication Year: 2025

Study Design

This study is an in vitro randomized controlled microbial trial using a validated Microbial Caries Model (MCM) to simulate dental plaque and caries formation in a laboratory setting.

Funding Sources

The study was funded by BIOM LLC, Sheridan, WY, USA. However, the funders did not participate in the study design, data analysis, interpretation, or manuscript writing.

PICO Framework - What Was Studied and How?

Population:
120 extracted sound bovine tooth enamel blocks subjected to artificial plaque biofilm formation.

Intervention:
Dentifrice tablet containing 5% nanohydroxyapatite (nHAP), applied twice daily as a slurry.

Comparison:

• Placebo dentifrice tablet (no nHAP or fluoride)

• Standard fluoride toothpaste with 1100 ppm sodium fluoride

• No-treatment control group

Outcomes:

• Tooth surface demineralization measured by Surface Microhardness (SMH) testing

• % Change in microhardness (%∆SMH)

• % Demineralization Inhibition compared to control

In Paragraph Form

This study evaluated whether dentifrice tablets containing 5% nanohydroxyapatite could prevent enamel demineralization as effectively as fluoride toothpaste (1100 ppm NaF) or placebo, using 120 bovine enamel blocks exposed to cariogenic biofilm in an artificial plaque model. Outcomes were based on surface hardness changes and demineralization inhibition.

Inclusion and Exclusion Criteria

Inclusion Criteria:

• Sound bovine teeth

• No cracks, white spot lesions, hypoplasia, or malformations

• Standardized tooth blocks (~5×5×2 mm) from buccal surface

Exclusion Criteria:

• Teeth with visible defects or enamel abnormalities

Demographics and Sample Design

• Total samples: 120 enamel blocks

• Groups:

  • NanoHAP Tablet Group: 30

  • Fluoride Toothpaste Group: 30

  • Placebo Tablet Group: 30

  • Control (No Treatment): 30

• Each group had equivalent baseline surface hardness (SMH) values.

Primary Outcome Variables and Results

Outcome: Surface Demineralization (% Demineralization)

• Control: 29.93% ± 5.58

• Placebo Tablet: 22.81% ± 7.47

• NanoHAP Tablet: 13.93% ± 11.31

• Fluoride Toothpaste: 14.44% ± 10.65

Statistical Findings:

• All treatments showed significant improvement vs. control (p < 0.05).

• No significant difference between NanoHAP and Fluoride.

• NanoHAP and Fluoride were both significantly better than Placebo (p < 0.01).

% Demineralization Inhibition (vs. Control)

• NanoHAP Tablet: 51.74% ± 40.05

• Fluoride Toothpaste: 50.56% ± 37.21

• Placebo Tablet: 21.86% ± 5.55

• No significant difference between NanoHAP and Fluoride.

• Both significantly better than Placebo.

Conclusions

This study found that toothpaste tablets containing 5% nanohydroxyapatite are as effective as fluoride toothpaste (1100 ppm NaF) in inhibiting tooth demineralization under high-risk cariogenic conditions. This suggests that nanoHAP-based toothpaste tablets may serve as a fluoride-free alternative for preventing early dental caries.

Discussion: Strengths and Limitations

Strengths:

• Simulated high-caries risk scenario with sucrose-fed biofilm in an artificial mouth model.

• Robust microbial caries model with mixed organisms (S. mutans and L. casei).

• Equal baseline hardness ensured comparability between groups.

• Strong statistical analysis and large effect sizes.

Limitations:

• In vitro setting limits real-world applicability (e.g., no brushing simulated).

• Use of bovine teeth may differ from human enamel in mineral content.

• Placebo tablet contained calcium carbonate, which may have partially masked the effect of nHAP.

Future Direction:
Clinical trials involving human participants and real-world brushing behavior are needed to confirm these findings.

Visual Aids

Simple Chart: % Demineralization and % Inhibition