Early dentine remineralisation: morpho-mechanical assessment

Area of Science:

• Dental research
• Materials science
• Biomineralization

Background:

• Dentine demineralisation is a precursor to dental caries.
• Understanding early remineralisation is crucial for developing effective treatments.
• The role of existing mineral content in demineralised dentine requires further investigation.

Purpose of the Study:

• To investigate physical-mechanical and morphological changes in demineralised dentine during early remineralisation.
• To evaluate the impact of various remineralising fluids on dentine.
• To assess the potential for early stimulation of dentine repair.

Main Methods:

• Human third molars were demineralised using phosphoric acid to create partially and totally demineralised dentine (PDD and TDD) models.
• Dentine samples were exposed to five different remineralising fluids (chlorhexidine, artificial saliva, phosphated solution, ZnCl2, ZnO) for 30 minutes.
• Techniques including Atomic Force Microscopy (AFM), nano-indentation, X-ray diffraction (XRD), energy dispersive elemental analyses (EDX), and High Resolution Scanning Electron Microscopy (HRSEM) were employed.

Main Results:

• Partially demineralised dentine (PDD) and totally demineralised dentine (TDD) retained some mineral content after demineralisation.
• Exposure to remineralising solutions increased the width of nanomechanical properties and fibrils while decreasing surface nanoroughness.
• Evidence of remineralisation was observed in both peritubular and intertubular dentine.

Conclusions:

• Mineral content within demineralised dentine matrix acts as nucleation sites for remineralisation.
• Dentine surface remineralisation can be initiated within 30 minutes under favourable abiotic conditions (pH 7.0-7.5).
• Enzymes and remineralising factors in dentine may enhance early repair, highlighting the potential for new restorative materials.