Dental Liners
What is the primary function of calcium hydroxide as a cavity liner?
Stimulates the production of reparative or secondary dentin. Protects the pulp from chemical irritation.
What is the main component of dental varnish?
Consists of one or more natural resins dissolved in an organic solvent.
What is the purpose of a dental base?
Provides pulpal defense/protection
What is the purpose of dental etchants in bonding?
To remove the smear layer in preparation for adhesion of a composite resin or sealant material to the tooth surface.
What steps are involved in the dentin bonding process?
Etch, Prime, Bond
• Protects the pulp from chemical irritation through its sealing abilities
• Stimulates the production of reparative or secondary dentin
• It has some antimicrobial action
• Mechanical and thermal insulating properties
How do dental varnishes help reduce microleakage?
By creating a physical barrier at the margins of a restoration, preventing fluid and bacteria from seeping into the gap between the tooth and the filling.
What types of pulpal protection do dental bases provide?
Protective, Insulating, and sedative protection.
Describe how dental etchants are typically supplied.
Supplied as a liquid or gel.
Why is it important to remove the smear layer before bonding?
Allows the dentin tubules to become open for the bonding material to flow into.
What is the purpose of a cavity liner?
Protects the dentin and pulpal tissues from irritation caused by physical, mechanical, chemical, and biological elements.
In what situation is dental varnish contraindicated?
The use of varnish is contraindicated with composite resin and glass ionomers because it will interfere with the bonding and setting reaction.
Why can zinc-oxide eugenol not be used under certain restorations?
The eugenol in the liquid will affect the setting process of the resin materials.
What is the recommended time for applying dental etchant?
15 - 20 seconds.
What are some examples of enamel bonding materials?
Where is calcium hydroxide placed?
Placed in the deepest dentin surface of the preparation.
What is the application process for dental varnish?
Using a microbrush apply the varnish all over the preparation, walls, floors, and margins. Air dry and apply a second coat with a new microbrush.
Name a commonly used insulating base material.
Polycarboxylate, ZOE, or Zinc Phosphate
It is a thin layer of ground-up enamel, dentin, and organic debris left on the surface after preparation. It can affect the adhesion of the dental material and tooth structure.
Describe the application of bonding solutions to the tooth surface.
The tooth surface receives the etchant material, which removes the smear layer; then the bonding component is allowed to flow into these small defects and into the partially opened tubules. Once this material is placed, it will :
(1) harden and act as a hybrid layer or (2) remain in a liquid state while the restoration is being placed, to bond together the tooth and the dental material
Describe the compatibility of calcium hydroxide with restorative materials.
Describe the role of fluoride varnish in dental care.
This gel-like substance is designed to release fluoride on enamel, root structure, and dentin structure.
How thick should a base material be applied?
1 to 2 mm
Explain the importance of moisture when bonding to dentin.
If dentin is completely dried, the tooth structure could be harmed.
What guidelines should be followed for clinical application of bonding products?
• Perform the steps in the bonding process precisely.
• Avoid expiration, contamination, and thickening of liquids.
• Remove any plaque or debris before beginning the bonding process.
• Avoid over-drying the dentin; these products work best on a slightly moist tooth structure.
• Note that too much bonding material is better than too little; multiple layers work best.
• Ensure that the bonding solution covers all surfaces.
• Avoid any contamination with saliva, blood, or debris; contamination will require the entire procedure to be redone.
• Allow as much time as possible for the bond to mature before completing the restoration and removing the cotton rolls or dental dam.