Isabella Pignatelli1, Aditya Kumar1, Kumar Shah2, Magdalena Balonis3, Mathieu Bauchy4, Benjamin Wu5, Gaurav Sant6. 1. Laboratory for the Chemistry of Construction Materials (LC(2)), Department of Civil and Environmental Engineering, University of California, Los Angeles, CA 90095, USA. 2. Division of Advanced Prosthodontics, School of Dentistry, University of California Los Angeles, CA 90095, USA. 3. Department of Materials Science and Engineering, University of California, Los Angeles, CA, USA; Institute for Technology Advancement (ITA), University of California, Los Angeles, CA, USA; Department of Bioengineering, University of California, Los Angeles, CA 90095, USA. 4. Physics of Amorphous and Inorganic Solids Laboratory (PARISlab), Department of Civil and Environmental Engineering, University of California, Los Angeles, CA 90095, USA. 5. Division of Advanced Prosthodontics, School of Dentistry, University of California Los Angeles, CA 90095, USA; Department of Materials Science and Engineering, University of California, Los Angeles, CA, USA; Department of Bioengineering, University of California, Los Angeles, CA 90095, USA; California Nanosystems Institute (CNSI), University of California, Los Angeles, CA 90095, USA. Electronic address: benwu@ucla.edu. 6. Laboratory for the Chemistry of Construction Materials (LC(2)), Department of Civil and Environmental Engineering, University of California, Los Angeles, CA 90095, USA; California Nanosystems Institute (CNSI), University of California, Los Angeles, CA 90095, USA. Electronic address: gsant@ucla.edu.
Abstract
OBJECTIVE: Remineralization and demineralization are processes that compete in the oral environment. At this time, numerous therapeutic agents are being developed to promote remineralization (precipitation) or suppress demineralization (dissolution). To evaluate the relative efficacy of such treatments, there is a need for non-invasive, real-time, high-resolution quantifications of topographical changes occurring during demineralization and remineralization. METHODS: Vertical scanning interferometry (VSI) is demonstrated to be a quantitative method to assess reactions, and topographical changes occurring on enamel surfaces following exposure to demineralizing, and remineralizing liquids. RESULTS: First, the dissolution rate of enamel was compared to that of synthetic hydroxyapatite (HAP) under acidic conditions (pH=4). Second, VSI was used to compare the remineralization effects of F(-)-based and CCP-ACP agents. The former produced a remineralization rate of ≈349nm/h, similar to simulated body fluid (SBF; concentration 4.6×) while the latter produced a remineralization rate of ≈55nm/h, corresponding to 1.7× SBF. However, the precipitates formed by the CCP-ACP agent are found to demineralize 2.7× slower than that produced by its F(-)-counterpart. SIGNIFICANCE: Based on this new VSI-based data, a remineralization factor (RF) and demineralization (DF) factor benchmarked, respectively, to 1× SBF and the demineralization rate of human enamel are suggested as figures of merit of therapeutic performance of dental treatments. Taken together, the outcomes offer new insights that can inform clinicians and researchers on the selection of remineralization strategies.
OBJECTIVE: Remineralization and demineralization are processes that compete in the oral environment. At this time, numerous therapeutic agents are being developed to promote remineralization (precipitation) or suppress demineralization (dissolution). To evaluate the relative efficacy of such treatments, there is a need for non-invasive, real-time, high-resolution quantifications of topographical changes occurring during demineralization and remineralization. METHODS: Vertical scanning interferometry (VSI) is demonstrated to be a quantitative method to assess reactions, and topographical changes occurring on enamel surfaces following exposure to demineralizing, and remineralizing liquids. RESULTS: First, the dissolution rate of enamel was compared to that of synthetic hydroxyapatite (HAP) under acidic conditions (pH=4). Second, VSI was used to compare the remineralization effects of F(-)-based and CCP-ACP agents. The former produced a remineralization rate of ≈349nm/h, similar to simulated body fluid (SBF; concentration 4.6×) while the latter produced a remineralization rate of ≈55nm/h, corresponding to 1.7× SBF. However, the precipitates formed by the CCP-ACP agent are found to demineralize 2.7× slower than that produced by its F(-)-counterpart. SIGNIFICANCE: Based on this new VSI-based data, a remineralization factor (RF) and demineralization (DF) factor benchmarked, respectively, to 1× SBF and the demineralization rate of human enamel are suggested as figures of merit of therapeutic performance of dental treatments. Taken together, the outcomes offer new insights that can inform clinicians and researchers on the selection of remineralization strategies.