Clinical Composite Flashcards
on average how long should composite inlays last
2.9 years
what is the most common problem with clinical composite
poor placing and handling of the material
what factors do we need to consider
- tooth biology
- materials science
- interfaces
- marginal seal
- manipulation
- polymerisation
- prism orientation (look at diagrams i dont understand)
what should be avoided in areas of occlusal contact
cavosurface margins
what does caries left at the ADJ result in
unsupported enamel and early breakdown of the restoration margin if microleakage occurs
what should be included in the design for interproximal caries access and removal
- no unsupported enamel
- proximal axial bevel
- gingival bevel
how can enamel fracture be avoided
- cavity design
- etch times
- washing
- curing protocol
what does a white line on your restoration after curing indicate
the restoration is doomed to an early failure
what is favourable for hybrid layer creation
primary dentine - open tubules
what is unfavourable for hybrid layer creation
tertiary dentine - irregular structure
not great to bond to
restoration contracts then there is a risk of failure
describe deeper dentine
- wetter
- more mineralised
- more tubes
describe older dentine
- fewer tubules
- more mineralised
- occluded tubules
describe reactive dentine
- occluded tubules
- more mineralised / contaminated
- irregular tubules
there are slides on hybrid layer and poor quality dentine that i dont understand because they are just lists
so probs look them up lol soz x
what type of dentine is good for bonding
freshly cut dentine
what things should be considered when working with enamel
- patient and cavity selection
- isolation
- choice of material
- choice of shade
- cavity preparation *
- bonding *
- contacts *
- placement *
- curing
- countering contraction stresses *
- finishing and polishing
- staining
- surface sealing
can you bond materials to caries?
no
all caries needs to be removed
define configuration factor
refers to the number of bonded surfaces to the number of unbonded surfaces in a dental restoration
define polymerisation contraction stress
an undesirable and inevitable characteristic of adhesive restorations encountered in clinical dentistry that may compromise restoration success
when the material is placed in just one increment it will shrink and pull away from the surface of the cavity and cause gaps
i can’t find a proper definition online :( i dont even know if the gaps part is right my notes confuse me
how does a high configuration factor affect polymerisation contraction stress
increased polymerisation contraction stress
how does a low configuration factor affect polymerisation contraction stress
reduced polymerisation contraction stress
define plasticity
a property of a material to undergo a non-reversible change of shape in response to an applied force (polymerisation)
define deformation
a change in shape due to an applied force (contraction)
state the clinical procedures of a restoration placement
- etch > enamel 10secs > dentine 10secs > leave surface slightly moist - prime - bond > these 2 are usually together - placement - characteristics - finish
what is the need for flowable composite
to mediate contraction stressed on interface and to achieve optimal adaption to non load bearing margins
where does the first increment go
on floor only
reservoirs for plastic deformation
what is the minimum intensity required to adequately cure 1.5mm to 2mm of composite resin
between 280 and 300 mW/cm2
when do you use a high power curing light
for fast curing
when do you use low power curing light
when working close to pulp
what is the main reason for reduced shrinkage stress
decreased final conversion
what is shrinkage direction determined by
bonded surfaces and free surfaces
when do composites shrink towards the light
when bonding fails
what is polymerisation of all materials due to?
halogen like emission spectrum (~380-515 nm)
what are the steps for clinical procedure for a restoration
- silicone matrix
- matrix in situ
- proximal strip added
- palatal enamel increment
- palatal / proximal shell
- contact areas restored with enamel
- dentine build up
- intensive white added for effect
- final enamel layers
- contouring
- preliminary polish
- penultimate polish
see pictures in lecture
what can poor quality dentine be covered by
resin glass ionomer
what should you check the gingival floor for when doing the proximal restoration
that you dont have overhangs
Who should you add on snapchat
ewan_kemp
