Class III and V Composite Restorations Flashcards
What are the steps to a class III prep?
- Evaluate contact
◦ Caries usually occurs gingival to interproximal contact - Visualize outline form
◦ 2.0mm inciso-gingival height, 1.5mm mesial distal width - Begin preparation by entering tooth with bur PERPENDICULAR to long axis
◦ I prefer 330 bur (lab manual recommends #2 round- ok to start with to establish outline, decide which works best for you)
◦ May place wedge prior to preparing
◦ Keep path of entry in mind
◦ Common error- preparation that is perpendicular to the lingual surface - Extend preparation
◦ Depth= slightly visible from facial
What are the steps in composite resin restoration?
- Acid Etch (Rinse/dry)
- Prime (often included in bond step)
- Bond/Adhesive (Light cure)
- Place Composite (Light cure)
What does acid etching accomplish?
- Increases surface area
- Adhesive penetrates etched enamel (creating micromechanical bond)
What is the total etch system?
- Etch
◦ enamel for 20-30 seconds
◦ dentin for 15 seconds.
◦ Apply etchant to enamel first; 15 seconds later apply it to the dentin then wash off the enamel and dentin at the same time. - Rinse thoroughly 15 seconds.
- Dry enamel with an air syringe.
- May selective etch ENAMEL ONLY 20-30 seconds, rinse, dry
◦ When using appropriate bond agent (e.g. Adhese, but any Universal)
What is a selective etch enamel?
ENAMEL ONLY 20-30 seconds, rinse, dry
◦ When using appropriate bond agent
How long do acid etch enamel and dentin?
◦ enamel for 20-30 seconds
◦ dentin for 15 seconds
If the tooth you are etching gets contaminated with saliva what should you do?
re-etch for 10 seconds and then rinse again and dry until frosted enamel appearance is present.
Teeth rich in fluoride require _______ etching times
longer
- because fluoridated teeth are more resistant to acid
Fluoridated teeth are resistant to the ____________ produced by bacteria
lactic acid
What is the primer?
◦ Hydrophilic monomers in solvent
◦ Draws adhesive in
◦ This step is included with adhesive in our clinic
What is the bond?
◦ Resin bonding agent
◦ Also referred to as “adhesive”
The thin bonding agent engages the etched enamel through a…
micro-mechanical bond
The self-curing or light-cured resin then _________ bonds to the bonding agent
chemically
Primer/adhesive penetrate the intertubular dentin forming…
hybrid layer
How do you apply bonding agent?
- Apply adhesive with a brush
- Thin the solvent by blowing air gently
- Don’t overly air-thin adhesive
What kind of bond do we use in clinic?
Adhese Universal
◦ Vivapen- one-click dispense
What can happen if you apply too much bond agent?
the excess gets all over the occlusal surface, interproximal, even adjacent teeth
How do you prevent composite from sticking to instruments?
◦ Dip instrument into small amount of adhesive to work with the composite
◦ May use Wetting Resin in practice
What can happen if composite pulls back on the instrument?
voids in the restoration