IADR Abstract Archives
Semi Real-Time Erosion of Human Dentine at the Nano-scale: An AFM Force-curve Based Imaging Study
Objectives: Dietary-acid mediated damage to tooth enamel results in softening and dissolution of mineral on the exposed surface. Once the enamel has been lost, dentine is exposed. Our knowledge of the role dietary acid concentration plays when pH is dietary relevant upon dentine erosion has yet to be established. We therefore investigated the effect of dietary acid pH and concentration when pH is dietary relevant, upon the morphological and mechanical property changes of short-term exposed human coronal dentine.
Methods: Human coronal dentine specimens (n=25) were obtained from 20 erupted 3rd molars and monitored using atomic force microscopy (AFM), operating in quantitative imaging™ mode (Force-curve based imaging). In vitro early stage erosion of human dentine was studied in terms of dietary relevant citric acid concentration and pH, monitoring changes in average roughness (Ra), load bearing area (δ) and stiffness (S) in a liquid environment (PBS, pH 7.2), over the same 50x50µm area, up to 180s, at 30s intervals.
Results: The severity of human dentine’s Ra (nm), and S (N/m) changes post treatment were found to be significantly influenced by acid concentration only (p<0.001), while the δ (nm) changes were influenced by both pH and concentration (p<0.001). Within the limitations of the study, human dentine erosion was found to be dominated by acid concentration, regardless of pH.
Conclusions: Of the acid characteristics analysed, dietary-acid concentration was found to be the dominant characteristic in the erosive severity of human dentine. Concentration-dependent changes in morphology and stiffness were obtained and were independent of acid pH. These findings could support the possibility to manufacture dentine-friendly drinks with an aim to lower acid concentration and or, focus on acid concentration in dentine erosion studies as the main driver of erosive severity, in both clinical applications and public health policy.
Methods: Human coronal dentine specimens (n=25) were obtained from 20 erupted 3rd molars and monitored using atomic force microscopy (AFM), operating in quantitative imaging™ mode (Force-curve based imaging). In vitro early stage erosion of human dentine was studied in terms of dietary relevant citric acid concentration and pH, monitoring changes in average roughness (Ra), load bearing area (δ) and stiffness (S) in a liquid environment (PBS, pH 7.2), over the same 50x50µm area, up to 180s, at 30s intervals.
Results: The severity of human dentine’s Ra (nm), and S (N/m) changes post treatment were found to be significantly influenced by acid concentration only (p<0.001), while the δ (nm) changes were influenced by both pH and concentration (p<0.001). Within the limitations of the study, human dentine erosion was found to be dominated by acid concentration, regardless of pH.
Conclusions: Of the acid characteristics analysed, dietary-acid concentration was found to be the dominant characteristic in the erosive severity of human dentine. Concentration-dependent changes in morphology and stiffness were obtained and were independent of acid pH. These findings could support the possibility to manufacture dentine-friendly drinks with an aim to lower acid concentration and or, focus on acid concentration in dentine erosion studies as the main driver of erosive severity, in both clinical applications and public health policy.
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