Effect of dentifrices on their remineralizing potential in artifi cial carious lesions: An in situ study

Abstract

Background: The eventual sequel of dental caries is determined by the dynamic equilibrium between
pathological factors which lead to demineralization and protective elements, which in turn leads to
remineralization. Remineralization is the natural process for noncavitated demineralized lesions and
relies on calcium and phosphate ions assisted by fl uoride to rebuild a new surface on existing crystal
remnants in subsurface lesions remaining after demineralization. Hence, the present study was designed
to evaluate the effi cacy of fl uoride dentifrices in remineralizing artifi cial caries-like lesions in situ.
Materials and Methods: A double-blind, randomized study with an initial washout period of 7 days
was carried out for 3 weeks. Twenty volunteers were enrolled, who wore the intraoral cariogenicity
test appliance having enamel slabs incorporated into them, for 3 weeks. 10 participants were
instructed to use Group A dentifrice (fl uoride) and the other 10 Group B dentifrice (nonfl uoride)
for brushing their teeth. The enamel slabs were analyzed by surface microhardness testing and
scanning electron microscopy (SEM) at 3 intervals.
Results: No signifi cant differences was seen in the microhardness values recorded for Group A
and Group B at baseline and after demineralization (P > 0.05); however Group B exhibited lesser
microhardness compared to Group A, after intra-oral exposure (P < 0.05). In the SEM analysis,
the Group A enamel surfaces had more regular and longer crystallites to those of the Group B.
Conclusion: Fluoride dentifrices avert the decrease in enamel hardness and loss of minerals from
the enamel surface to a large extent as compared to the nonfl uoride dentifrices.

Key Words: Dental caries, dentifrices, fl uoride, tooth remineralization