minimal intervention dentistry – the challenge for materials

Minimal Intervention Dentistry – The Challenge for Materials

John W. NicholsonUniversity of Greenwich

Minimal Intervention Dentistry

- Modern approach to the treatment of tooth decay- Based on “Medical Model” of caries management

Historical Development of Dentistry

- Extraction; - Surgical approach (“drilling and filling”): after G.V. Black;- Medical approach – Minimal Intervention.

G.V. Black

- Developed in the 1890s;

- Highly formalised cavity design;

- “Extension for prevention”.

Critique of G.V. Black’s approach

- A surgical model; - Caries “cured” by excision, then filling;- Appropriate for weak, non-adhesive materials; - Still the prevailing paradigm in the profession.

The Minimal Intervention approach

- A medical model;

- Caries treated as a biological infection;

- Surgical techniques are minor and stress retention of tooth tissue.

Details of the MI approach

- (1) Reduces cariogenic bacteria;

- (2) Uses preventive measures;

- (3) Early lesions remineralised;

- (4) Minimal surgery on cavities;

- (5) Repair of defective restorations.

(1) Cariogenic bacteria

• Caries is a bacterial disease;

• Depends on dietary sucrose;

• Driven by frequency of eating;

• Modified by saliva.

(2) Preventive measures

• Topical fluoride;

• Fissure sealants;

• Patient education on oral hygiene

(3) Remineralisation

• Requires management by non-intervention;

• Enhanced by fluoride ion in saliva.

(4) Minimal surgery

• Requires adhesive materials (glass-ionomers, adhesive composite systems);

• Innovative, bespoke cavity design:– Possibly without drilling (ART technique).

(5) Repair of materials

• To prevent cavity extension;

• Not “botch job”, but appropriate.

The challenge for materials

• Adhesion– Occurs naturally for glass-ionomers; problematic for

composites.

• Fluoride-release;

• Release of other mineralising ions (PO4, Ca2+);

• Repairable.

Conclusions

• Minimal Intervention dentistry is the future:– Advocated by FDI;– Cost effective;– Less trauma for the patient.

• A biological approach, not a mechanical one.

• Makes significant demands on materials.