Lecture 9- Posterior Composite Restorations

When can we restore posterior teeth using direct composite resin?

primary carious lesions (tooth surface that has disease carious) and secondary carious lesions (Replacement of composite and amalgam restorations)

Contraindications of restoring posterior teeth using direct composite resin:

• large restorations (causes the walls to be thin and potential crack)

• when a tooth cannot be adequately isolated

• tooth with heavy occulsal stress

Advantages of composite restorations:

• Esthetics

• Conservative tooth structure removal

• Easier, less complex tooth preparation

• Decreased microleakage

• Increased strength of remaining tooth structure

Disadvantages of composite restorations:

• Polymerization shrinkage effects

• Lower fracture toughness than most indirect restorations

• More technique-sensitive than amalgam restorations

• Possible greater localized occlusal wear

• Unknown biocompatibility of some components (bisphenol A [BPA])

Class I Restorations: Clinical Protocol

1) Anesthesia

2) Pre-operative occlusion

3) Prophylaxis

4) Tooth color matching

5) Operative field isolation

6) Cavity preparation

7) Adhesive System

8) Composite placement

9) Final light cure

10) Checking the occlusion

11) Finishing and polishing

light cures ____, the not phosphoric acid etch

adhesive (aka g-bond)

C-Factor

bonded surfaces/ unbonded surfaces (higher c-factor = more stress)

more resin = ___ shrinkage, more filler particles = ____ shrinkage

more; less

what resin brand do we use?

filtek supreme

Incremental filling technique on occulsal:

cusp by cusp (many increments)

We cure enamel for ___, and dentin for ___

20 seconds; 40 seconds

air block step:

for the last incremention use glyceral gel then cure again to get rid of of oxygen inhibited layer

3 bonding agents:

• etch-and-rinse bonding agent (strongest enamel bond, but more sensitive on dentin)

• self-etch bonding agent (gentler, easier, less sensitivity, but weaker enamel bond)

• universal (flexible, combines both approaches, relies on functional monomers)