Modification of Cavity Form for Different Materials Flashcards
Describe caries infected dentine
- Deminerlisation of dentine
- Denaturing of collagen
- Irreversible
Describe caries affected dentine
- Demineralisation of dentine
- No denaturing of collagen
- Reversible
What are the aims when removing enamel as you try to remove caries
- Gain/widen access to caries
- Remove unsupported prisms
- Remove demineralised margins
What are the aims when removing dentine as you try to remove caries
- Identify caries infected dentine
- Identify peripheral extent to EDJ
- Excavate CID peripherally then towards pulp (anatomical)
- Excavate CID in depth (histological)
After Caries infected dentine has been removed what is the next step in caries removal
Considering whether more carious dentine removal is necessary
If you do want to remove more carious dentine what reasons might there be to do so
- Poor quality peripheral enamel precluding seal
- Inadequate moisture control at margin precluding seal (e.g. at gingival margin)
- Symptoms of pulpitis
- High caries risk
- Further structural support needed
- CONSIDER DIRECT/INDIRECT PULP CAPPING
Give examples of ways that we can carry out cavity modification
- Rounded internal line angles
- Increase surface area of enamel margins (bevel)
- Chemical modification of cavity walls (acid etch/conditioners)
What reasons might you have to not remove any further dentine after CID removal
- Remaining CAD retained
- Good quality/quantity of peripheral enamel
- Good moisture control at cavity margin
- Further excavation may make tooth unrestorable
Why should we restore teeth
- To remove diseased tissue
- To restore integrity of tooth structure
- To restore function of tooth
- To restore appearance of tooth
- To prevent recurrence of caries (microleakage)
- To provide durability and longevity
What factors determine cavity design
- Structure and properties of dental tissues
- Extent and nature of dental diseases
- Properties of proposed restorative material
What can we do to modify a cavity on a macroscopic level
- Created using a bur
- Air rotor for slow handpieve
What can we do to modify a cavity on a microscopic level
- Created chemically
- Tissue conditioning
What is retention
The property of a cavity/restoration that resists displacement of a restoration in the direction of its insertion
What is resistance
The property of a cavity/preparation that prevents displacement of a restoration in apical or oblique directions (other directions)
What is the cavo-surface angle
This is the angle between the internal surface of the cavity of the tooth and the surface of the tooth
What is a line angle
This is the angle between 2 surfaces
What is an internal point angle
This is where 3 sides meet
What kinds of external walls can there be in a cavity
Distal
Facial
What kinds of internal walls can there be in a cavity
Pulpal
Axial
What are direct and indirect restorations
Direct - placed directly into the tooth
Indirect - Placed, but made or fabricated in an external lab