Class V

• Located in the gingival one third of the facial and lingual tooth surfaces?


  CLASS V TOOTH PREPARATION
• Factors to be considered in class V tooth preparation:

  1. Caries
  2. Gingival health
  3. esthetics
  4. Sensitivity
  5. pulp protection
  6. tooth strength
• Caries. If active caries is present, caries management should be initiated.
• For the incipient lesion, treatment may consist of application of a topical fluoride or resin-based materials including adhesives and resin infiltration materials.
• Inactive lesions may be monitored and kept unrestored indefinitely, but sometimes these can be esthetically unsatisfactory. (Most NCCLs are not carious.)
• If the defect is determined to be contributing to the development of gingival inflammation and/or gingival recession (i.e., plaque retention, mechanical trauma due to poor tooth contours), the defect should be restored?


  Gingival health
• Factor: If the defect is in an esthetically critical position, the patient may elect to have the area restored with a tooth-colored restoration?

  Esthetics
• Factor: If the defect is very sensitive, application of an adhesive or desensitizing agent may reduce or eliminate the sensitivity, at least temporarily.

  Continuing sensitivity may require restoration of the area.
• Factor: If the defect is very large and deep pulpally, its restoration may be indicated to avoid further defect development that may cause a pulpal exposure
• Factor: If the defect is very large or deep, the strength of the tooth at the cervical area may be compromised.
• factor: Placement of a bonded restoration reduces the potential for further progression of the defect and may restore some of the lost strength.
• factor: Periodontal therapy with gingival grafts also may be considered

  as a treatment option for these exposed root surfaces being used solo or combined with the restorative therapy
• How many line and point angles are there in class V?

  8 line angles and 4 point angles
• Line angles in class V?

  ● Axiogingival

  ● Axioincisal

  ● Axiomesial

  ● Axiodistal

  ● Mesioincisal

  ● Mesiogingival

  ● Distoincisal

  ● Distogingival
• Point angles in class V?

  ● Axiodistogingival point angle

  ● Axiodistoincisal point angle

  ● Axiomesiogingival point angle

  ● Axiomesioincisal point angle
• In conventional class V tooth preparation, shape of the preparation is?

  Kidney shaped
• Isolate the area


  1. Use tapered fissure bur

  2. Make entry at 45 degree angle to tooth surface initially
• After this

  1. Keep long axis of bur perpendicular to the external surface

  2. Get a cavosurface angle of 90 degree
• During initial tooth preparation

  Keep the axial depth of 0.65 mm into the dentin
• After achieving the desired dental distal extension

  1. Move the bur mesially

  2. Move the bur incisally (occlusally)

  3. Move the bur gingivally

  4. Place the preparation margins onto the sound tooth surface

  5. Maintain a cavosurface margin of 90 degree
• Axial wall

  • Should follow the contour of facial surface incisogingivally
  • Should follow the contour of facial surface mesiodistally
• Indications of Conventional tooth preparation In class V?

  ● If caries is present completely or mainly on root surface

  ● If lesion is partly on crown and partly on root, then crown portion is prepared using beveled conventional or modified preparation design and the root surface lesion is prepared by conventional method
• Indication in beveled conventional toot prepartion in class V?

  1. For replacing defective existing restoration
  2. Forr restoring a large, carious lesion
• Initial axial wall depth in beveled conventional tooth preparation in class V is limited to?

  0.25mm into the dentin
• Retention grooves depth if placed?

  0.5mm
• Bevel measurement of the enamel margins in beveled conventional tooth preparation?

  0.25mm-0.5m wide
• When class V lesion extend onto the root surface, gingival preparation has conventional class V design with the initial axial depth of 0.75mm. Beveling is done only on enamel cavosurface margins.
• Roughen the dentin with diamond bur to provide mechanical retention in beveled conventional tooth preparation
• Indications of Modified (conservative) tooth preparation in class V?

  1. Restoration of small and moderate carious lesions and defects.
  2. Small enamel defects like decalcified and hypoplastic areas present in cervical third of the teeth
• Modified class V tooth is prepared as discussed in the previous modified preparation. Final tooth preparation should have “scooped out” appearance with divergent walls and axial wall either in enamel of dentin
• All margins on sound tooth structure

  Extent of preparation on tooth surface, depends on caries extent

  Outline form
• • 0.25mm-0.5mm bevel on enamel margins
  • Form, shape, and configuration of the tooth preparation that resists the displacement or removal of restoration form the preparation under lifting and tipping masticatory forces

  Retention form
• • Axial depth 1-1.5 mm
  • Depth is slightly greater at the occlusal wall than the gingival wall
  • Axial. contour follows tooth contour
  • Internal form of cavity that allows restoration to resist forces of mastication

  Resistance form
• • Occlusogingival width of 1-1.5mm
  • Form of tooth preparation to allow physical and visual accessibility to preparation

  Convenience form
• • Preparation measurements are determined by the extent of the carious lesion or existing, faulty restoration
  • If areas of decalcification are present, conservative extension of the preparation can be included in the outline form. The depth will be only until the defect is removed
  • If the lesion etiology is abrasion, erosion, or abfraction, the lesion requires only cleaning with a non-fluoride pumice (slow speed rotary), roughening with a diamond bur and beveling as preparation.
• • Axial wall: 1-1.5mm deep, with the depth slightly greater at the occlusal wall than the gingival wall
  • Axial contour follows tooth contour
  • Occlusogingival width: 1-1.5 mm
  • Bevel: 0.25-0.5mm on enamel margins
• Checklist