Materials for Luting and Adhesion Flashcards
what are the main objectives of cementation?
- help maintain restoration in place
- maintain integrity of remaining tooth structure
retention via cementation is achieved by what?
- friction
- adhesive joint
- the cement and/or the restoration
an effective interfacial seal depends on the ability of the cement to do what?
fill the irregulatirites between the tooth and the restoration and to resist the oral environtment over the short and long term
why is it important for there to be a strong bond between the luting agent and the dental substrates?
it can prevent infiltraiton of bacteria and fluids that can cause caries and sensitivity to the patient
what are some common substrates that cement can be used to bond?
- cast alloys
- ceramics
- indirect composites
- amalgam
- fiber posts
- repair of composite, ceramic, and ceramic-metal restorations
how are luting agents classified?
- according to the length of time that they are expected to stay in function:
- provisional and definitive
- and also according to setting:
- acid based reaction and setting by polymerization
name 4 materials that are capable of creating a chemical interaction with hydroxyapatite
- zinc polycarboxylate
- GI
- RMG
- self-adhesive resin cements
describe minimally invasive dentistry
- preservation of a healthy set of natural teeth for each patient should be the objective of every dentist
- all work in the health field is aimed basically at conservation of the human body and its function
what are 3 important considerations when choosing adhesives?
- dentin morphology and physiology
- adhesive systems
- adhesive dentsitry - case reports
describe buonocore 1955
- found that acid etching of the enamel increases the bond strength of resin to enamel
- the practice of bonding to enamel has become a routine procedure in many fields of dentistry
approximately half of all restorations placed in general dental practices are done to replace a defective or failed restoration. what are the 3 main categories that reasons for restoration replacement can be divided?
- clinician factors
- material properties
- patient factors
what is the composition of dentin?
- 50% mineralized apatite crystals
- 20% water
- 30% organic matrix (collagen fibrils)
describe the variation of water content from superficial to deep dentin
- diameter and number of tubules increases near the pulp
- 20,000 tubules/mm^2 at DEJ
- 45,000 tubules/mm^2 close to pulp
describe sclerotic and caries-affected dentin
- hypermineralized
- tubules occluded with CaPO4 crystals
- acid-resistant
what is an issue with over-drying dentin?
collagen fibers are susceptible to collapse upon over-drying
