bonding to teeth

Question 1

what properties do you want for a dental adhesive?

Answer 1

provide high bond strength to tooth tissues
immediate high strength bond
durable bond
impermeable bond
easy to use 
safe

Question 2

what effect does the acid in acid etch have on the surface of enamel

Answer 2

roughens surface producing etched pattern

this rough surface allows micro mechanical interlocking

Question 3

is enamel bonding mechanical or chemical?

Answer 3

mechanical

Question 4

after enamel is etched which substance is applied?

Answer 4

resin

Question 5

why is bonding to dentine more complicated than enamel?

Answer 5

smear layer in dentine
dentinal fluid
low surface energy in dentine
dentine is hydrophilic and most bonding agents are hydrophobic

Question 6

what bonding forces are used to bond to dentine?

Answer 6

Van Der Waals forces and mechanical bonding

Question 7

does wet dentine have a low or high surface energy?

Answer 7

low

Question 8

composite has a higher surface energy than dentine, in order for it to adhere, dentine surface energy will have to increase greater than that of composite, how is this achieved?

Answer 8

bonding agent will increase surface energy of dentine

Question 9

which substance removes the smear layer?

Answer 9

acid etch

Question 10

name the 3 components of total etch

Answer 10

dentine conditioner
primer
adhesive

Question 11

what purpose does dentine conditioner have?

Answer 11

removes smear layer opening dentinal tubules

decalcifies upper most layer of dentine

Question 12

dentine primer has a hydrophobic and hydrophilic end, which end binds what?

Answer 12

hydrophilic end binds hydrophilic dentine

hydrophobic end binds resin

Question 13

name a coupling agent found in dentine primers?

Answer 13

HEMA

Question 14

what are the problems with total etch?

Answer 14

removes all hydroxyapatite
collapse of collagen fibres so resin can penetrate
creates deep etch a primer cannot penetrate
moisture dependant

Question 15

total etch application consists of how many steps?

Answer 15

2

Question 16

what type of etch technique is most common?

Answer 16

separate etchant with combined primer and sealer

Question 17

which etch technique does not attempt to remove the smear layer/

Answer 17

self etch

Question 18

what is the downside of self etch?

Answer 18

bondto dentine not as strong as other techniques

materials with low ph may not etch enamel

Question 19

what is a pro of self etch?

Answer 19

less technique sensitive than other techniques

less chance of post op sensitivity

Question 20

mineral exchange where minerals are removed from dental hard tissue and replaced with resin which once mineralised mechanically interlocks in the porsities is known as?

Answer 20

molecular entanglement