IADR Abstract Archives
Penetration Depth and Efficacy of 8DSS Peptide in Enamel Remineralization
Objectives: The synthetic peptide 8DSS, inspired by dentin phosphoprotein, reportedly promotes mineralization of dental hard tissues. This study aims to evaluate the penetration depth and spatial distribution of 8DSS within the enamel microstructure and to characterize the effect of 8DSS concentration on its remineralization efficacy.
Methods: Extracted healthy human third molars were cut into blocks and subsurface caries lesions were created using 0.05M acetate buffer (pH:4.6) for 7 days. A solution of fluorescein-labelled 8DSS at 20µM in 50mM HEPES buffer (pH:7.2) was applied for 10 minutes on intact (n=4) and demineralized (n=4) enamel surfaces, rinsed with DI water, fractured longitudinally and analyzed under 488nm excitation using a Zeiss LSM880 confocal microscope. Additional samples with subsurface lesions were exposed to a 5-hour demineralization (pH:4.6), 5-minute 8DSS solution and 19-hour remineralization (pH:7.0) cycle for 5 days to mimic the oral cavity conditions (n=8). Effects of different 8DSS concentrations (10 or 20µM) on remineralization of the lesions were evaluated using backscattered and secondary electrons imaging modes on a JEOL-7900F SEM on fractured enamel blocks.
Results: No penetration of 8DSS peptide was observed on intact, non-demineralized, enamel surfaces. When 8DSS was applied to samples with artificial subsurface caries lesion, the peptide penetrated up to 100µm deep into lesions. The lesions were no longer visible after application of 20µM 8DSS while remineralization occurred only on the enamel surface with 10µM 8DSS use.
Conclusions: 8DSS peptide penetrates fully into artificially demineralized enamel lesions and can induce remineralization over the entire depth of the lesion depending on its concentration. 8DSS does not penetrate into the intact enamel surfaces and is not likely to affect healthy enamel. The penetration depth of 100µm makes 8DSS a promising peptide for use in enamel repair and supports previous reports of 8DSS use for remineralization.
Acknowledgments: Forsyth Advanced-Imaging Core, Harvard University Center for Nanoscale Systems.
Methods: Extracted healthy human third molars were cut into blocks and subsurface caries lesions were created using 0.05M acetate buffer (pH:4.6) for 7 days. A solution of fluorescein-labelled 8DSS at 20µM in 50mM HEPES buffer (pH:7.2) was applied for 10 minutes on intact (n=4) and demineralized (n=4) enamel surfaces, rinsed with DI water, fractured longitudinally and analyzed under 488nm excitation using a Zeiss LSM880 confocal microscope. Additional samples with subsurface lesions were exposed to a 5-hour demineralization (pH:4.6), 5-minute 8DSS solution and 19-hour remineralization (pH:7.0) cycle for 5 days to mimic the oral cavity conditions (n=8). Effects of different 8DSS concentrations (10 or 20µM) on remineralization of the lesions were evaluated using backscattered and secondary electrons imaging modes on a JEOL-7900F SEM on fractured enamel blocks.
Results: No penetration of 8DSS peptide was observed on intact, non-demineralized, enamel surfaces. When 8DSS was applied to samples with artificial subsurface caries lesion, the peptide penetrated up to 100µm deep into lesions. The lesions were no longer visible after application of 20µM 8DSS while remineralization occurred only on the enamel surface with 10µM 8DSS use.
Conclusions: 8DSS peptide penetrates fully into artificially demineralized enamel lesions and can induce remineralization over the entire depth of the lesion depending on its concentration. 8DSS does not penetrate into the intact enamel surfaces and is not likely to affect healthy enamel. The penetration depth of 100µm makes 8DSS a promising peptide for use in enamel repair and supports previous reports of 8DSS use for remineralization.
Acknowledgments: Forsyth Advanced-Imaging Core, Harvard University Center for Nanoscale Systems.