Abstract
Background and objectives: In conditions of chronic saliva reduction or absence, dental caries significantly impact oral health. The objective of the current study is to evaluate the effectiveness of silver diamine fluoride (SDF) treatment on the remineralisation of dentine caries under reduced saliva conditions.
Methods: Twenty-four bovine dentine specimens with artificial caries lesions were prepared. Specimens were divided into four treatment groups (n=6 per group), two groups received one-off SDF treatment and the remaining two received distilled water as control. The specimens underwent 14 days of pH cycling designed as a simplified model of dynamic intraoral conditions. pH cycling conditions differed in pH, duration, and volume of the solutions to mimic normal and reduced saliva conditions. The elastic modulus, hardness, elemental analysis and crystal characteristics were assessed by nanoindentation, scanning electron microscopy energy dispersive X-ray (SEM-EDX), and X-ray diffraction (XRD), respectively.
Results: The hardness of dentine treated by SDF and water were 0.27 ± 0.10 GPa and 0.15 ± 0.06 GPa, respectively in normal saliva condition (p=0.05); 0.44 ± 0.07 GPa and 0.13 ± 0.07GPa, respectively in reduced saliva condition (p<0.001). The elastic modulus of dentine treated by SDF and water were 11.00 ± 4.30 GPa and 5.25 ± 3.08 GPa, respectively in normal saliva condition (p=0.017); 11.21 ± 2.35 GPa and 3.56 ± 0.86 GPa, respectively in reduced saliva condition (p=0.003). XRD analysis indicated that silver chloride was formed on the dentine surfaces treated by SDF.
Conclusion: The use of SDF is effective in inhibiting demineralisation of dentine caries under reduced saliva conditions, consistent with that in normal saliva conditions