what is it called when two atoms + and - share electrons in the outer shell completely fulling the shell making for a very strong bond
what kind of bond does teracylcine staining form?
what is two examples of weak bonds, the atoms do not share electrons
van der Vaals bonds
what five ways are materials classified by?
what is known as young's elastic modulus?
inability to bend
what has volume but no shape?
______=flow easier under mechanical force
what is an example of tixotropic
seating a crown-having the pt bite down
what are two things that would be classified as preventative?
pit and fissure sealants
what are three examples of things that would be classified as therapeutic
periodontal disease topicals
what is the largest classification of materials?
what are two categories of the restorative classification? give examples of both
direct-amalgam and composite
indirect-porcelain fused to metal crown
what are two reactions from combining two components?
physical-evaporation or cooling of liquid
what are the two stages that happen when combining two components?
what is the manipulation stage of combining two components
mixing time-components homogenous
working time-manipulate material in mouth
what is the reaction stage of combining two components?
initial set time-no longer able to manipulate
final set time-ultimate state
______ control is critical if contamination occurs = ______
t/f postoperative instructions to the patient are critical
t/f the material must not be disturbed through the end of the final set
t/f moisture and pressure controls are frequently important during the initial set
t/f the final set always occurs while the pt is still in the dental office
t/f once a material has reached the initial set, it will not fracture
what instructions should you follow when manipulating dental materials
t/f all dental materials should be kept in a warm, dry location
false- refer to manufactures recommendations for storage
ch 3 physical properties of dental materials