Dental Caries Management Quiz

Management of Deep Caries

• Deep caries is a progressive, irreversible disease of tooth calcified tissues.
• It's characterized by demineralization of the inorganic component and destruction of the organic substance.
• Management of deep carious lesions is challenging due to skill, knowledge, experience, armamentarium and professional capabilities required.
• The operator must prioritize pulp protection, retention, resistance, and esthetics.
• Irritation from carious processes are from three causes:
  • Biological irritation from bacteria and toxins
  • Chemical irritation due to acids
  • Physico-mechanical irritation arising from declining dentin bridge structure as decay progresses.

Types of Decay

• Acute caries: Rapid, strong irritation with little chance for recovery.
  • Demineralized dentin is light yellow/yellow, due to rapid acid infusion.
  • Surface has a wet/moist texture.
  • Soft, flakes off easily during excavation.
  • Care must be taken during excavation to avoid pulp exposure, following a direction parallel to the pulp.
• Chronic decay: Accompanied by substantial repair.
  • Periods of elevated irritation/destruction followed by restorative periods.
  • Dark brown color due to chromogenic bacteria with dry texture.
  • Arrested caries (remineralized) is slightly darker.
  • Darkest area of demineralized dentin indicates the oldest part of the lesion.

Duration of Decay Process

• Acute decay (rapidly progressing caries): Rapid destruction of tooth structure. Longer untreated acute lesions result in greater pulpo-dentinal organ damage, and rapidly induce pulp exposure.
• Chronic decay: Longer duration increases repair chances, provided the pulp tissue isn't directly involved.

Depth of Involvement

• Deeper caries leads to greater irritation intensity and risk of pulp destruction. Deeper involvement places irritant sources closer to the pulp, reducing its protective barrier.
• Effective depth is the thickness of the dentin bridge along dentinal tubules. It reflects the irritant pathway length to the pulp.
• Effective depth of 2mm or more indicates healthy reparative reaction; 0.8-2mm indicates an unhealthy reaction; less than 0.3-0.8mm indicates pulpal involvement.

Number and Pathogenicity of Micro-organisms

• Number and pathogenicity of invading micro-organisms significantly affect decay activity (acuteness or chronicity).
• Type and metabolic activities of bacteria in the lesion, and the surrounding oral environment affect dentin demineralization and proteolysis rates.

Tooth Dentin Resistance

• Resistance of hard dentin to spread of decay.

Individual Reaction of the Pulp-Dentin Organ

• Ability of tissues to defend caries can vary between individuals and cases, even for the same caries type/extent.
• Factors include patient age, health, cellularity/vascularity of pulpal tissues, and immune response, as well as structural and periapical condition of the affected tooth.

Clinical Management of Deep Caries Lesions

• Treating deep caries approximating healthy pulp is challenging.
• Traditional methods (removing all carious dentin to reach sound tissue) are invasive and risk over-preparation/pulp exposure.

Now we are going for Conservative Dentistry

• Not all carious dentin is infected with cariogenic micro-organisms.
• Outer carious dentin is infected (brownish), while inner is sterile (yellowish).
• Differentiating these is challenging.
• Removing all soft carious dentin isn't always necessary if the remaining dentin can be sealed well.

Direct Pulp Capping

• Procedure for lining a pulp exposure with a medicament liner (calcium hydroxide or MTA).
• Seals the cavity, stimulating reparative dentin bridge formation.
• Pulp exposure during preparation may be a result of caries progression or trauma.
• Micro-scopic exposures only appear as open tubules, reaching the pulp.

Criteria for Direct Pulp Capping Candidates

• No signs/symptoms of pulp degeneration.
• Sufficient evidence of reasonable reparative capacity in P-D organ.
• Completely aseptic field of operation (isolated by rubber dam).

Direct Pulp Capping Characteristics

• Pinpoint exposure, small diameter compared to pulp size.
• Minimal to no observable hemorrhage (coagulated blood if any).
• Reparable dentin at periphery (verified visually/tactically).
• Exposure site not constricted.

Direct Pulp Capping Procedures

• Collect data regarding P-D organ physiology.
• Remove undesirable and/or undermined enamel/unsound dentin.
• Wash/irrigate cavity floor/exposure site with sterile water.
• Dry using sterile cotton pellets, not air spray.
• Ca(OH)2 or MTA used as capping material.

Additional Notes

• Stepwise (two-step) and partial (one-step) excavation protocols are described.
• Maintaining a good peripheral seal helps prevent bacterial access to nutrients causing further decay.
• Success of treatment depends on understanding and proper handling of these challenges.