mini assessment 2 Flashcards
1-preventive management plan for caries
2-operative management plan for caries
3-indications for restin composite restorations
1-xylitol gum, sealants for at risk grooves,
periodic recall, re-evaluation in changes in enamel
2-restoration of 18 & 19, restoration of 14 & material of choice
3-isolations hould be possible
- esthetics should be important
- facial lingual width of prep shouldnt be more than 1/3 intercuspasl distance
- cavosurface margins should be on enamel
- small to mdoerate restorations, w/o heavy occlusal contacts
- patients shouldnt be allergic to materials
1-resin composite restoration advs
2-resin composite restoration disadvs
1-conservative—only carious area has been removed
- bonds to tooth structure—no additional retentive features must be cut into the tooth structure—margins are sealed w/ bonding
- esthetic—tooth colored
2-technique sensitive—several steps in bonding & must be moisture controlled
- post op sensitivity
- takes more time to place comp restorations
- more expensive (than amalgam)
1-components of resin composite
2-composite
3-macro fill
4-microfill
5-nanofill
6-hybrid
1-inorganic filler—quartz, silica, glasses
- coupling agent —silane
- resin matrix—bis-GMA, UDMA
- initiator—camphoroquinone (light activator)
2-composite declassified by inorganic filler particle size
- filler particle size & amt control properties of composite
- tetric evo ceram= nano hybrid
3-10-100 um
4-.01-.1 um
5-.005-.01 um
6-mixture of small particle & microfill… .4-1 um
1-imp properties of composite
2-modulus of elasticity
1-wear resistance
- ability to resist surface loss as a result of abrasive contact w/ opposing tooth structure, food, toothbrush
- influenced by particle size, filler particle amt, location of restoration, & occlusion
2-stiffness of material
- high modulus of elasticity= more rigid
- microfill = more flexible than a hybrid composite
- –lower modulus of elasticity
- –more flexible materials where teeth flex under occlusal
- –abfractions, smooth surface restorations in cervical area
—-composite = more flexible while amalgam= higher modulus of elasticity (rigid)
1-polymerization shrinkage
2-coefficient of thermal expansion
1-shrinkage after curing (material poly)
- careful technique helps to reduce poly shrinkage but it cant be elimated so have to place it in increments w/ curing
- shrinkage= gap formation at margins when force of shrinkage is greater than bond strength= non enamel margins
2-change in dimension bc of change in temp
- closer the coefficient of thermal expansion of material is to that of the tooth structure= less chance for creating gaps
- composite can have 1-4x the coefficient of thermal expansion than tooth structure
1-composite
2-clinical procedure
1-amt of filler particles—usually between 30-70% weight & between 50-85% volume
- inc filler = inc physical & mechanical properties= reduction of poly shrinkage, & reduction in thermal expansion/contraction
- control of viscosity
- radiopacity
2-anesthetic admin, check occlusion w/ articulating, & pumice the teeth= removing stain, plaque & debris
1- shade selection
2-moisture control
3-rubber dam isolation
1-composite shades are selected prior to rubber dam
- teeth become lighter in shade if they become dessiccated
- when teeth rehydrate= the resin will be too light
- posterior teeth= not a big deal but w/ anterior it is
2-rubber dam isolation= exclude damage of high humidity on dentin bonding
3-isolation of area,
humidity/mositure and contamination control,
visibility & tissue retraction/protection
1-preparation
1-open cavitated areas w/ bur to facilitate caries removal= high speed used to open enamel
- evaluate DEJ to see if carious lesion has spread along DEJ
- once grooves are open, soft carious dentin is excavated w/ large slow speed round bur or spoon excavators
- prep extension to gain access to soft dentin= convenience form
- unsupported enamel is removed—enamel must be supported by sound dentin, unsupported enamel can fracture w/ open margin around restoration and must follow enamel rod direction
- unaffected grooves & not prepared
1-open margin
2-prep 2
3-what happens during prep
4-bonding system
1-collects debris and leads to decay around restoration= secondary decay or recurrent decay
2-no minimum depth for prep for composite
- depth of prep is determined by depth of lesion
- pulpal floor may be uneven in depth bc of variation in depth of lesion
3-preparing dentin= smear layer, smear layer= debris, calcific in nature, produced by reduction of dentin, enamel, or cementum or contaminane that precludes interaction w/ underlying tooth structure—.5-2 um thickness
4-etchant, primer, & adhesive
1-etch
2-bonding
3-enamel bonding
4-etching dentin
5-rinse
1-etch & rinse system
30-40% phosphoric…etch enamel 15-30 sec, etch dentin 10-15 sec
-demineralization
rinse- keep dentin moist
smear layer is removed—if not kept wet then the layer isnt removed & it dries back up
2-apply bonding resin to etched enamel & dentin
- keep wet w/ bonding agent for 10 s
- agitation
3-surface demin, creats areas irregularities that allow for bonding= micromechanical
4-etch & rinse= removes smear layer
- rinsing w/o etching doesnt remove smear layer
- superficial demineralization
5-rinse surface, remove excess moisture—dentin= glossy, w/ air for 1-2 s
-dentin must remain moist for bonding
1-bonding agent
1-primer= hydrophyllic monomer
adhesive= hydrophobic monomer
solvent= acetone/ethanol/alcohol
initiator/activator
-bonding agent (primer/adhesive) is applied to enamel/dentin w/ agitation or scrubbing
-excess is thinned w/ weak stream of air
-light cured
-hybrid layer is formed
1-hybrid layer
2-what happens if dentin is dried too much
3-bonding
1-formed by infiltration of demin dentin (collagen remains) by bonding agent (monomers)
2-poor infilitration of the bonding agent thin hybrid layer
3-thin bonding agent w/ weak air
- no pooling of bonding agent
- cure for 10 s
- surface= glossy, forming hybrid layer
1-light activated composite
2-curing light
1-bonding agents & resin composite are light activated
- provides extended working time
- operatory light will begin to cure material= dec working time
- use composite safe light while bonding/placing composite
2-valo light (LED), 3 settings (standard, high, plasma), standard setting for routine procedures (green light, 5 sec)
1-light curing
2-composite
3-curing time
4- insert composite
1-type of light, exposure time, distance of light to restoration , & angulation of tip
2-type of composite (microfill takes longer to cure)
shade of composite (dark shades take longer)
thickness of increments( not bigger than 2 mm
3-if too light can effect properties of composite, if too much inc temp in pulp chamber
4-incremental placement & curing, cure after each increment (20 s) & shape anatomy before curing
use alc swab so it doesnt stick
1-tetric evo ceram
2-composite wetting resin
3-excessive use
4-seal remaining groove
1-80-82% filled by weight, 68% by volume
2-45% filled
3-excessive use of wetting agent or bonding agent= dilute the composite
4-place sealant material over unpreped grooves
- cure
- finish & polish
- remove rubber dam
- check occlusion & adjust
