Natural products offer promising solutions in prosthodontics and oral implantology

Infection control is paramount in prosthodontics and oral implantology to prevent complications like denture stomatitis and peri-implantitis. While synthetic disinfectants (e.g., chlorhexidine) are widely used, their side effects-including mucosal irritation, toxicity, and antimicrobial resistance-drive the search for safer alternatives. Natural products derived from plants, animals, and minerals offer promising solutions due to their antimicrobial efficacy, biocompatibility, and environmental sustainability.

Key natural agents and mechanisms

Plant-based products:

• Clove oil (eugenol), tea tree oil (terpinen-4-ol), neem (azadirachtin), and green tea extract (epigallocatechin gallate, EGCG) disrupt microbial cell membranes, inhibit biofilm formation, and suppress virulence genes.

• Cinnamon oil (cinnamaldehyde) targets quorum sensing and bacterial cell walls.

Animal-derived products:

• Propolis (flavonoids, phenolic acids) and honey (hydrogen peroxide) inhibit microbial growth, promote wound healing, and reduce inflammation.

Mineral/microbial products:

• Clay minerals and bacteriocins (e.g., nisin) absorb toxins and disrupt microbial membranes.

These agents act via:

1. Direct antimicrobial effects (membrane disruption, enzyme inhibition).

2. Biofilm disruption (blocking adhesion, exopolysaccharide suppression).

3. Anti-inflammatory actions (curcumin inhibits pro-inflammatory cytokines).

Applications

Prosthodontics:

• Denture disinfection: Clove oil, thyme oil, and propolis reduce Candida albicans colonization.

• Material incorporation: Adding phytoncides to denture bases (e.g., PMMA resins) inhibits microbial growth.

• Oral rinses/gels: Herbal mouthwashes with neem or cranberry extract match chlorhexidine in efficacy against Streptococcus mutans.

Oral implantology:

• Implant surface disinfection: Totarol coatings on titanium surfaces prevent bacterial adhesion long-term. Essential oils (cinnamon, clove) enhance wettability, reducing biofilm risk.

• Peri-implantitis management: Propolis and EGCG reduce pathogenic bacteria (e.g., Porphyromonas gingivalis) and inflammation. Adjunctive use with mechanical debridement improves outcomes.

Advantages and challenges

Advantages:

• Biocompatibility, low toxicity, and ecological sustainability.

• Synergistic effects (e.g., lipid-soluble EGCG + antibiotics inhibit biofilms by >99%).

Challenges:

• Variability: Inconsistent composition due to extraction methods and source differences (Fig. 3a-h).

• Regulatory gaps: No FDA approval; classified as OTC products.

• Limited clinical data: Small-scale trials and lack of standardized protocols hinder translation.

Future directions

1. Nanotechnology: Liposomes/nanoparticles enhance stability and targeted delivery of natural agents.

2. Clinical validation: Large-scale trials (Phases II/III) for peri-implantitis applications.

3. Standardization: Protocols for extraction, formulation, and quality control.

Conclusion

Natural disinfectants-notably propolis, EGCG, and clove oil-hold significant potential as sustainable, safe alternatives to synthetics. Addressing standardization and regulatory barriers through rigorous research will facilitate their integration into mainstream dental practice.