Adhesive Materials Flashcards
What is adhesion?
joining together of two objects using glue or cement.
What is the science of adhesive bonding?
- Mechanical interlocking (effective on roughened or etched surfaces)
- Chemical Bonding: Silane coupling agent and phosphoric acid etching.
What is Phosphoric acid etching?
increases surface energy for bonding with resin cements.
What is silane coupling agents?
Bond to ceramic and glass based materials
What is macro-mechanical adhesion?
bonding through large scale, which can be seen with the naked eye or magnification
What are micro-mechanical adhesion?
bonding that occurs when an adhesive interlocks with a roughed surface
enamel or dentin is etched to creat a rough surface
bonds are stronger than macro-mechanical.
What is enamel etching?
- Etching enamel wtih acid creates microporsities within its highly mineralized surface.
- A very fluid adhesice resin primer is applied to the surface and cured
- it micromechanically retained by the irregularities
What happen if you over etch an enamel?
can form crystals from the phosphate and calcium ions that are initally dissolved which inhibits bonding.
How does the etching process works for dentin and what does it need?
- removes smear layer
- moist collagen noodles
- mineral underneath
It needs something hydrophilic
What is priming ?
- Primers are typically composed of monomers that penetrate etchen surfaces, preparing them for the bonding agent.
- primimg promotes adhesion
- hydrophilic and hydrophobic balance
- seals tubules
what is hydrophilic?
- manages moisture content on the tooth surface
What is hydrophobic balance?
promotes adhesion
What is amphiphilic?
cotnains both hydrophilic and hydrophoic propteries
What role does primers play in sealing tubules?
- reduces senstivity and provides a more uniform surface for the adhesive.
What is a total-etch adhesive?
- total surface to be bonded gets etched
- smear layer is removed and primer applied and cured.
