Quiz 2 Flashcards
What is true of the smear layer?
It interferes with the formation of a bond to dentin and needs to be removed.
The smear layer forms on the surface of the cut dentin and enamel and is composed mostly of cut tooth structure.
What must the chemical training program for employees include?
The use of hazardous chemicals, all safety practices, required personal protection devices, and safe handling and disposal methods.
This includes all warnings.
Which statement is true concerning bond strength?
Wetter dentin with more holes is more difficult to bond to consistently than shallower dentin.
Bonding to enamel usually achieves consistently high bond strengths of around 30 MPa.
What is a basic safe policy for storing dental medications and chemicals?
Keep them in a dry, cool, dark place where they are not exposed to direct sunlight.
Changes in chemical composition can occur due to exposure to light and heat.
Through which medium is dust generated and inhaled?
Particulate matter.
Dust can be generated during the manipulation of dental materials.
Who provides SDSs?
The manufacturer.
SDSs must be obtained for every chemical used in the office.
For how many seconds should dentin be etched?
10 seconds.
Enamel should be etched for a total of 20 seconds while dentin is etched for only 10 seconds.
When does microleakage occur?
When contaminants are not removed.
Contaminants can contribute to microleakage during the bonding process.
When are posts placed within the roots of endodontically treated teeth?
When coronal tooth structure is inadequate for restoration with a crown.
Silanes are used with which dental materials?
Porcelain.
Silanes are coupling agents that bond to the resin in the bonding agent.
What is a symptom of acute chemical toxicity?
Nausea.
Other symptoms include dizziness, fainting, headache, and vomiting.
What is used to remove excess water during post cementation?
A paper point.
What is the most commonly used etchant for tooth bonding?
Phosphoric acid in concentrations ranging from 10% to 38%.
Acid removes mineral from the surface to create roughness.
What must materials transferred to smaller containers be labeled with?
Either a photo of the original label or a specially made secondary label.
Etch gel is typically a/an _____ solution of phosphoric acid.
37%.
The enamel of permanent teeth is usually etched for 20 to 30 seconds with this concentration.
What part of the chemical hazard communication program describes how chemicals are handled?
Written program.
When acid etching for bonding, what is desirable?
A high surface energy and a low angle of contact.
When should a rubber or neoprene apron be worn?
When mixing or pouring chemicals that are caustic.
What is correct regarding the dual-cure process for resin bonding agents?
Can be activated by light or can cure chemically without application of the curing light.
Hypersensitivity may occur when _____ are irritated by procedures or chemicals.
Odontoblasts.
This sensitivity usually lasts for a short time after a bonded restoration.
