Changes in mineral density and nanomechanical properties of enamel white spot lesions by dentifrices with different active ingredients for remineralisation - an in vitro study.

Objectives:This study aims to evaluate the remineralisation potential of fluoridated dentifrices with added active ingredients compared to a standard fluoride dentifrice with no additional active ingredients. Methods: Artificial demineralised enamel lesions were formed by placing premolars into demineralising solution. The teeth were randomly assigned to 4 groups and subjected to 10-days pH cycling: Group 1: Sensodyne repair and protect® containing Novamin®; Group 2: Clinpro Tooth Crème® containing functionalised tricalcium phosphate; Group 3: Colgate® Cavity Protection containing 1450ppm fluoride; Group 4: Distilled water. Mineral density (MD) was assessed using Micro-CT while elastic modulus (EM) and hardness (H) were assessed using nanomechanical testing. Results: Mean MD percentage gain was highest in Groups 1 and 2, followed by Group 3 and lowest in Group 4. There was no significant difference in mean MD percentage gain between Groups 1 and 2. Also, no significant differences were evident in the EM and H between the outer layer of the treated lesions of Group 1, Group 2 and Group 3 which were significantly higher than Group 4. The EM and H of the inner layer of the treated lesions were highest in Groups 1 and 2, followed by Group 3 and lowest in Group 4. Conclusions: All tested dentifrices effectively remineralised the demineralised enamel lesions. The added active ingredients penetrated and remineralised the deeper parts of the carious lesions. However, there was no significant difference in remineralisation at the lesion surface between the tested dentifrices. Clinical Significance: The use of dentifrices with enhanced remineralisation potential would benefit population with high caries risk and those with limited access to dental care. This could lead to a decrease in cavitated carious lesions and a reduction in the burden of treatment costs to patients and funding bodies