Direct Posterior Restorations Flashcards
(27 cards)
Give 4 conditons causing tooth loss.
- Caries
- Tooth wear
- Developmental/genetic disorders
- Trauma
Give 7 reasons for restoring teeth.
- Facilitate plaque removal and restore a cleansable tooth surface.
- Restore appearance
- Restore form, function and structural integrity of the tooth
- Arrest carious process
- Prevent pain
- Protect the pulp
- Prevent drifting/tilting if contact point is lost
What 5 questions do we ask ourselves before removing caries?
- How extensive is the lesion?
- Is it in enamel, at the EDJ or into dentine?
- Caries risk assessment of the patient?
- How likely is it for the carious lesion to progress?
- Is the cavity cleansable?
Why do we use minimally invasive techniques?
To preserve tooth tissue.
Give 5 minimally invasive techniques.
- Prevention - OHI/diet/topical fluoride
- Facilitating OH and decreased plaque accumulation
- Silver Diamide Fluoride
- Atraumatic restorative techniques
- Chemo-mechanical caries removal
What is a direct restoration?
- Restoration placed in cavity directly by a dentist.
- Material sets after placement in the cavity.
What is a indirect restoration?
- Impression taken from cavity, sent to lab.
- Restoration is made in lab and then cemented in the mouth.
What restorations do extra coronal cavities require?
- Indirect
- This covers the surface of tooth and cusps.
What restorations do intra coronal cavities require?
- Direct or indirect.
- These are occlusal cavities.
With indirect restorations why is the cavity made to be wider at the top?
- As you can get the excess cement to come out.
- This forms a better seal and the restoration is seated better.
After making the cavity what 3 things must you do/decide on?
- Decide what materials are to be used.
- Is there a need for lining
- Adjust the cavity so it is suitable for the materials to be used.
When removing caries, where do you remove from first and why?
EDJ and walls then floor (roof of pulp)
Caries removed from EDJ and walls first so that most of the bacteria are removed before going anywhere near the pulp to decrease the risk of bacterial contamination of the pulp.
What caries must be removed and what dentine may have to be removed?
- Soft caries aka infected dentine.
- Stained dentine may have to be removed if it is likely to show through enamel.
When can stained dentine be left behind and why is this?
- Hard
- The dentine has only demineralised.
- Demineralisation precedes bacterial penetration so the hard stained dentine is still viable (if it isn’t seen through enamel)
When is lining used and why has it been phased out?
Lining refers to placing a thin layer of material between the tooth and a filling, often to protect the pulp (nerve area) or help reduce sensitivity.
- Only over the exposure so you do not affect the seal between filling and tooth.
- If there is no exposure, there is no need for lining as the filling material and tooth provide a better seal from bacterial invasion.
Define retention in cavities.
Any feature of the cavity which stops the restoraiton from falling out in any direction.
Give 3 types of retention.
- Mechanical
- Micro mechanical
- Chemical
Give 6 forms of mechanical retention.
- Angulation of the walls of the cavity
- Undercuts
- Pits/Grooves
- Pins: stainless steel /titanium / amalgam
- Nayyar core
- Posts
Give 4 forms of microi-mechanical retention.
- Acid etch/resin
- Acid etch/dentine bonding agents
- Amalgam bonding
- Bond between composite and GIC
Give 1 form of chemical retention.
Glass ionomer cement.
Define resistance of a cavity.
Features of the cavity which stop the restoration from failing in other ways.
Give 6 reasons for failure in the resistance of a cavity.
- Wrong colour
- Fracture of the tooth
- Fracture of the restoration
- Recurrent caries
- Margin failure
- Pulpal problems
How is fracture of the restoration prevented by the resistance of a cavity?
By having:
- Thick material
- Smooth rounded cavity.
How is fracture of the tooth occur due to the resistance of a cavity?
- Unsupported enamel
- Weak walls.
