Topical and systemically administered fluoride is widely accepted to prevent dental caries. However, there is still debate regarding the biological mechanism by which fluoride achieves its anticaries effect. Objective: the aim of the present study was to apply atomic force microscope (AFM) to investigate the surface structure of enamel crystals after treatment with fluoride ions. Methods: Protein-free developing enamel crystals were obtained from the maturation stage of rat incisors. These enamel crystals were treated with 0, 0.01M, 0.05M, 0.1M, 0.5M, 1.0M NaF solutions (pH 7.4). The Eppendorf tubes containing the treated specimens were placed in a water bath at 37 °C and shaken for 18 hours. After centrifuging, the crystals were washed 6 times with water and dispersed onto a mica surface prior to surface roughness measurements with a Nanoscope IIIa AFM. The mean roughness in a small area (~30 nm x 30 nm) was determined and the average crystal roughness was calculated. Differences in surface roughness measurements were compared statistically using an unpaired t test. Results: The crystal surface roughness increased with increasing fluoride ion concentration [NaF concentration (M) / Roughness of Crystal Surface: 0.0 M / 0.77, 0.01 M / 0.95, 0.05 M / 1.14, 0.1 M / 1.22, 0.5 M / 1.78, 1.0 M / 1.81]. Conclusion: The changes in the surface roughness of the crystals will affect their surface reactivity, which in turn, may change their remineralisation potential. Supported by NIH grants DE12899.

Back to the Mineralized Tissue Program
Back to the IADR/AADR/CADR 82nd General Session (March 10-13, 2004)

Top Level Search