BPD: Pit and fissure sealing

Tooth anatomy (development groove, fissures, pits and fossae)

• Developmental groove: A narrow depression separating tooth lobes.

• Fissure: A deep groove caused by incomplete fusion of tooth lobes.

• Pit: A small depression where grooves meet or end.

• Central fossa: A depression on the occlusal surface where several grooves converge.

• Central pit: A pit within the central fossa, often susceptible to caries.

Important: Pits can also occur on the lingual surfaces of maxillary incisors, especially lateral incisors, below the cingulum.

Fissure anatomy (types of fissures)

• Fissures are classified according to their shape:

  • U-shaped: Similar width from top to bottom.

  • V-shaped: Wide opening, gradually narrowing towards the bottom.

  • I-shaped: Very narrow slit.

  • IK-shaped: Narrow entrance with a wider space at the bottom.

  • Inverted Y-shaped: Narrow entrance with branching at the bottom.

• Important: Narrow and deep fissures are particularly difficult to clean and may retain bacteria.

Pit and fissure sealing

• Pit and fissure sealing is a preventive procedure in which a protective material (sealant) closes pits and fissures to prevent dental caries.

  Why is it needed?

  • Deep pits and fissures are difficult to clean because toothbrush bristles cannot reach them.

  • Bacteria and plaque accumulate, increasing caries risk.

  • Recently erupted teeth have less mature, more porous enamel.

• Main benefit: Creates a protective barrier that prevents bacteria and food from accumulating in fissures.

Indications and contraindications for sealing

• Indications:

  • Deep pits, fissures or fossae that are difficult to clean.

  • Teeth with increased caries risk, especially permanent molars.

  • Patients with high overall caries risk.

  
  

• Contraindications mentioned in the lecture:

  • Inability to keep the tooth dry (poor cooperation).

  • Open carious lesions.

  • Large existing occlusal restorations.

  • Restorations on other surfaces that would interfere with the sealant.

  Important: The patient’s caries risk is more important than the time since tooth eruption.

When should sealants be applied

• Typical ages:

  • 3–4 years: Deciduous molars.

  • 6–7 years: First permanent molars.

  • 12–13 years: Second permanent molars.

  
  

• Benefits:

  • Effective in preventing occlusal caries.

  • Relatively inexpensive compared with restorations.

  • Painless, quick and easy to apply.

• Important: Sealants should be monitored over time because their protective effect depends partly on retention.

Types of sealant materials

• Key difference: GIC is more moisture-tolerant, whereas resin-based sealants require a dry surface

Classification of fissure sealants

1. Polymerisation:

• 1st generation: UV-light cured.

  • The material has a fotoinitatior

• 2nd generation: Chemically cured.

• 3rd generation: Visible-light cured.

• 4th generation: Visible-light cured with fluoride.

2. Fillers:

• Unfilled: Better flow into narrow fissures.

• Semi-filled: Greater wear resistance.

3. Colour: Clear, opaque, tinted, etc.

Ideal properties: Good flow, strong and long-lasting adhesion, wear resistance, low toxicity, insolubility, dimensional stability and rapid curing.

Steps for pit and fissure sealing

1. Clean/polish: Remove deposits using fluoride- and oil-free paste.

2. Isolate: Keep the tooth dry (e.g., rubber dam or cotton rolls).

3. Etch: Apply 37% orthophosphoric acid for 15–30 seconds to create enamel microporosities.

4. Rinse and dry: Remove acid and dry the surface.

5. Apply sealant: Allow material to flow into fissures and remove air bubbles.

6. Cure: Light-cure for the required time if using a light-cured material.

7. Evaluate: Check sealant coverage and retention.

8. Check occlusion: Ensure the bite is not disturbed.

9. Final polish: Use fluoride-containing paste.

Why etch? Microporosities allow resin to penetrate the enamel and form resin tags, producing mechanical retention.

Exteneded pit and fissure sealing

• Conventional sealing: Covers pits and fissures to prevent caries without removing tooth structure.

  
  

• Extended sealing: Includes minimal removal of small carious lesions before applying the sealant.

  • Considered secondary prevention because early carious defects are treated.

  • Uses minimally invasive instruments, such as fissurotomy burs or microabrasion devices.

  • Preserves as much healthy enamel and dentin as possible.

• Important: If the lesion reaches dentin, a bonding material is needed to improve adhesion, according to the lecture.

Fissurotomy system

• The fissurotomy system uses specially designed burs to minimally enlarge fissures and remove small carious lesions.

  
  

• Advantages:

  • Removes less healthy tooth structure than conventional burs.

  • Mainly cuts enamel, reducing discomfort.

  • Often does not require local anaesthesia.

  • Allows treatment of small lesions while preserving healthy enamel and dentin.

  
  

Procedure: Minimal fissure preparation → conventional sealing procedure.