IADR Abstract Archives
Effects of Chitosan on Remineralisation of Enamel Lesions in vitro
Objectives: Chitosan, a derivative from chitin, can penetrate into enamel, bind with enamel prisms and attracts anions, thus potentially enhancing remineralisation of incipient lesions. The objective of this study is to test the null hypothesis that chitosan treatment has no impact on the remineralisation of artificial incipient enamel white spot lesions (WSLs).
Methods: 48 artificial human enamel WSLs were assigned to 6 experimental groups (n = 8): (1) bioactive glass slurry (BG), (2) bioactive glass containing polyacrylic acid (BG+PAA) slurry, (3) chitosan pre-treated WSLs with BG slurry (CS-BG), (4) chitosan pre-treated WSLs with BG+PAA slurry (CS-BG+PAA), (5) “standard” remineralisation solution (RS) and (6) de-ionised water (negative control, NC). All samples went through a 7d pH-cycling. Chitosan pre-treatment was carried out by dropping 40 μL solution (2.5 mg/mL) on lesion surface for 60s. Remineralisation was conducted by applying specific agents on lesion surface and then brushing for 3min. In-situ surface and cross-sectional Raman intensity mapping was performed on 5 samples per group to assess surface and subsurface mineral content. Surface and cross-sectional Knoop microhardness were used to assess the mechanical properties after remineralisation. Data were statistically analysed using one-way ANOVA with Tukey’s test (p < 0.05).
Results: BG and CS-BG presented significantly higher surface mineral regain compared to NC after pH-cycling (p < 0.05), while no significant difference was found on subsurface regions. All experimental groups except RS showed greater surface hardness recovery than NC (p < 0.05). CS-BG and CS-BG+PAA presented greater increase than non-chitosan-treated groups. On subsurface sections (20 μm below the surface), both CS-BG and CS-BG+PAA showed greater hardness value compared to NC (p < 0.05).
Conclusions: The null hypothesis was rejected. Chitosan pre-treatment enhanced WSL remineralisation with either BG only or with BG/PAA complexes.
Methods: 48 artificial human enamel WSLs were assigned to 6 experimental groups (n = 8): (1) bioactive glass slurry (BG), (2) bioactive glass containing polyacrylic acid (BG+PAA) slurry, (3) chitosan pre-treated WSLs with BG slurry (CS-BG), (4) chitosan pre-treated WSLs with BG+PAA slurry (CS-BG+PAA), (5) “standard” remineralisation solution (RS) and (6) de-ionised water (negative control, NC). All samples went through a 7d pH-cycling. Chitosan pre-treatment was carried out by dropping 40 μL solution (2.5 mg/mL) on lesion surface for 60s. Remineralisation was conducted by applying specific agents on lesion surface and then brushing for 3min. In-situ surface and cross-sectional Raman intensity mapping was performed on 5 samples per group to assess surface and subsurface mineral content. Surface and cross-sectional Knoop microhardness were used to assess the mechanical properties after remineralisation. Data were statistically analysed using one-way ANOVA with Tukey’s test (p < 0.05).
Results: BG and CS-BG presented significantly higher surface mineral regain compared to NC after pH-cycling (p < 0.05), while no significant difference was found on subsurface regions. All experimental groups except RS showed greater surface hardness recovery than NC (p < 0.05). CS-BG and CS-BG+PAA presented greater increase than non-chitosan-treated groups. On subsurface sections (20 μm below the surface), both CS-BG and CS-BG+PAA showed greater hardness value compared to NC (p < 0.05).
Conclusions: The null hypothesis was rejected. Chitosan pre-treatment enhanced WSL remineralisation with either BG only or with BG/PAA complexes.