Dental Anatomy and Pulp Irritation Quiz

Pulp Irritation

• Extreme temperatures, chemical irritation, or microorganisms can cause irreversible pulpitis.
• Pulp size can be evaluated on a radiograph and decreases with age.
• Excessive pressure, higher rotational speeds, and the type, shape, and condition of the cutting instrument increase generated heat.
• Even with the lightest touch, the tooth overheats unless a water spray is used.
• Bases, Restorative Resins, Solvents, and Luting Agents can cause palpal damage, particularly when they are applied to freshly cut dentin.
• All carious dentin should be removed before placement of a restoration that will serve as a foundation for a fixed prosthesis.

Tooth Structure Conservation

• Use of partial coverage rather than complete coverage restorations
• Preparation of teeth with the minimum practical convergence angle (taper) between axial walls
• Preparation of the occlusal surface so that reduction follows the anatomic planes to give uniform thickness in the restoration
• Preparation of the axial surfaces so that a maximal thickness of residual tooth structure surrounding pulpal tissues is retained
• If necessary, teeth should be orthodontically repositioned
• Selection of a margin geometry that is conservative and yet compatible with the other principles of tooth preparation
• Avoidance of unnecessary apical extension of the preparation

Margin Placement

• Supra-gingival Margin: They can be easily finished without associated soft-tissue trauma
• Supra-gingival Margin: They are more easily kept plaque free
• Supra-gingival Margin: Impressions are more easily made, with less potential for soft tissue damage
• Supra-gingival Margin: Restorations can be easily evaluated at the time of placement or at recall appointments
• Subgingival Margin: Dental caries, cervical erosion, or restorations extend subgingivally

Biological Considerations

• Teeth do not possess the regenerative ability found in most other tissues
• Once enamel or dentin is lost as a result of caries, trauma, or wear, restorative materials must be used to reestablish form and function

Surgical Precision

• Surgical procedures on living tissues require careful execution to prevent unnecessary damage
• Inadequate marginal fit or deficient crown contour resulting from poor preparation can complicate plaque control around fixed restorations

Damage to Adjacent Structures

• Teeth, soft tissues, and the pulp of the prepared tooth are susceptible to damage during tooth preparation
• Common error in dentistry involves iatrogenic damage to adjacent teeth during procedures
• Reshaping and polishing a damaged proximal contact area may not prevent increased susceptibility to dental caries compared to the original undamaged tooth surface
• To protect the adjacent tooth, use a metal matrix band and a thin tapered diamond
• To prevent damage to the soft tissues, use retraction with an aspirator tip and mouth mirror.