Interplay Between Minerals in Bottled Water and Fluoride Toothpaste and Caries Lesion Remineralization

Area of Science:

• Dental Research
• Cariology
• Biomaterials Science

Background:

• Dental caries remains a significant global health issue.
• Fluoride toothpaste is a cornerstone of caries prevention.
• The role of water composition in enhancing remineralization efficacy is not fully understood.

Purpose of the Study:

• To investigate the in vitro effect of different bottled waters on the efficacy of fluoride and fluoride-free toothpastes.
• To evaluate the impact of varying calcium (Ca) and fluoride (F) concentrations in bottled water on enamel remineralization.
• To compare the remineralization potential of different water sources when used with standard toothpaste formulations.

Main Methods:

• Bovine enamel specimens with induced early caries lesions were used.
• A 2x5 factorial design tested fluoride vs. fluoride-free toothpaste against four bottled waters and tap water.
• Specimens underwent a 10-day pH-cycling regimen with twice-daily toothpaste slurries and water exposures.
• Vickers surface microhardness (VHN) was measured before and after treatment to determine the change (ΔVHN).

Main Results:

• A significant interaction (p<0.001) was observed between water type and toothpaste fluoride content.
• All tested groups showed significant enamel remineralization (increased VHN), except for fluoride-free toothpaste with bottled water containing 0.1 ppm Ca/0.04 ppm F.
• Fluoridated toothpaste significantly outperformed fluoride-free toothpaste (p<0.001) across all water types.
• Bottled water with 1.20 ppm F/309.9 ppm Ca demonstrated the highest remineralization extent with fluoride toothpaste (p<0.001).
• Tap water showed significantly less remineralization compared to all tested bottled waters when used with fluoridated toothpaste (all p<0.001).

Conclusions:

• Bottled water composition, particularly higher fluoride and calcium levels, can enhance the remineralization efficacy of fluoridated toothpaste.
• Specific bottled water formulations may offer an advantage in improving dental enamel repair.
• Further research is warranted to confirm these findings in vivo and explore optimal water compositions for caries management.