Dentin Degradation: From Tissue Breakdown to Possibilities for Therapeutic Intervention

Area of Science:

• Dental biomaterials science
• Caries research
• Dentin-pulp complex biology

Background:

• Caries etiopathogenesis is complex, involving both bacterial and host factors.
• Traditionally, bacteria were solely blamed for dentin degradation.
• Emerging evidence highlights the role of host enzymes like matrix metalloproteinases (MMPs) and cathepsins.

Purpose of the Study:

• To review current evidence on host and bacterial contributions to dentin degradation, inflammation, and repair in caries.
• To clarify the roles of host and bacterial by-products in caries progression.
• To explore new therapeutic avenues for dentin-pulp complex regeneration.

Main Methods:

• Literature review of studies on dentin degradation, inflammation, and repair in caries.
• Analysis of host-derived enzymes (MMPs, cathepsins) and bacterial factors.
• Examination of pulp responses to bacterial invasion and inflammation.

Main Results:

• Host enzymes (MMPs, cathepsins) contribute to dentin breakdown and are activated by bacterial-induced low pH.
• Saliva and pulp are additional host sources of enzymes involved in caries progression.
• MMPs exhibit dual roles, regulating both degradation and repair mechanisms in the dentin-pulp complex.
• Inflamed pulp shows elevated MMPs and cathepsins, with MMPs potentially resolving inflammation and promoting healing.

Conclusions:

• The interplay between host and bacterial factors in caries progression requires further elucidation.
• Understanding the complex interactions between inflammation and repair is crucial for managing dentin-pulp complex changes.
• This knowledge can drive the development of novel dental biomaterials and therapies targeting specific repair mechanisms.