Week 1 - Operative Dentistry II Flashcards
why is isolation important
- better visualization
- better access
- prep walls dry and clean
- materials will work better
- prevents injury to patient soft tissues
- prevents aspiration and swallowing of debris
how does isolation make your materials work better
- improved properties- direct contact of varnish/liner/base with cavity walls
- moisture affects bond as well as materials ability to set up
what are the components of dental dam set up
- rubber sheet, clamp, frame, punch, forceps
what side of the rubber dam faces the operator
the dull side
what are the different sizes of rubber dams
- 5x5 for pediatric patients
- 6x6 for adults
what are the different thicknesses of dams
- thin 0.006”- used for very tight contacts
- medium 0.008”
- heavy 0.010
- extra heavy 0.012
- special heavy 0.014
what can the frame be made of
- metal
- plastic - can be radiographed
which tooth gets the largest hole
the anchor tooth
what are the forceps used for
the place clamp
holes in clamp correspond to:
extension in forceps
what are the parts of retainers (clamps)
- bow
- jaws
- forceps holes
- points
what are the types of retainers (clamps)
- winged or wingless
- points can be rounded, can be bent to flatten
why is isolation so important in composite cases
- bonding requires uncontaminated surface
- technique sensitive
what does wet field result in in composite cases
recurrent caries or failed bond
when doing a class II what teeth should you isolate
one tooth posterior to the tooth youre working on and two teeth anterior
what should to isolate when working on anteriors
canine to canine or can clamp on one premolar
what do you isolate in peds cases
only isolate teeth necessary
what do you isolate in endo
single tooth
what is general isolation/FDP
may be acceptable to cut a slit between holes
what are the steps in placing the rubber dam
- prep work: punch holes in rubber, check contacts for floss shredding, mark occlusion
- place clamp in dam and tie with floss
- place dam over tooth
- stretch dam through contacts and floss contacts
- invert dam
- ligate anterior tooth
what does it mean to invert the dam
blow air around cervical area and push rubber into sulcus with plastic instrument
what should you used if rubber dam doesnt work
- antisialogogue meds: atropine and banthine (rarely used)
- absorbents: cotton rolls, dry shields, 2x2 gauze, cotton pellets
- suction: high evacuation suction, saliva ejector, svedopter
- isovac
what should you keep in mind when using cotton rolls
- place them in vestibule
- wet when removing to avoid cotton roll burn
what do dry shields do
- blocks parotid gland, retracts and protects cheek
- also wet when removing to avoid cotton roll burn
what does 2x2 gauze work well as
throat pack
which absorbent is least effective
2x2 gauze
when do you used cotton pellets
- remove moisture from inside prep
- remove moisture when patient is sensitive to air and water spray
what is high evacuation suction used for
- vented is better- reduces sucking up of tongue and mucosa
- very effective at picking up debris
- can be used to retract tissue
- leave room for water from handpiece to cool the tooth
describe the saliva ejector
- ineffective at removing debris
- do NOT have patient close lips around suction because of backflow
what are some additional isolation tools
- retraction cors
- bite block
- anterior lip retractors
once ideal outline form is achieved:
remove caries
what should you remove caries with
-spoon excavator
- round bur on slow speed hand piece
how should you refine your prep and what do each of these things do
- plane axiopulpal line angle to reduce stress
- plane gingival margin- use margin trimmer to remove loose enamel rods
where should you place the wedge in an amalgam restoration
in the larger embrasure
what are the steps to performing an amalgam restoration
- fill box - 1.0mm above margins
- begin carving- carve mesial incline of marginal ridge using explorer, pre carve burnish, carve with hollenback
- remove tofflemire and wedge
- remove band- hold condenser on marginal ridge as you do this
- interproximal - carve before it sets up
what should you do after amalgam restoration is complete
- check contacts with floss and remove buccal/lingual
- check occlusion with articulating paper
- burnish groove anatomy
- smooth with wet cotton pellet
what should you clean the tooth with before a composite prep
pumice and water mixture
describe the proximal outline form of a composite prep
- must break gingival margin
- caries must be removed
- matrix band must fit passively
- break lingual contact
- break buccal contact…or not
where do caries occur in class II
below the contact
where should margins be kept in composite preps
in enamel
what should only be removed in composite preps
carious tooth structure
what should the buccal wall be in amalgams? composite?
-amalgam- S curve
- composite- flare
what is the pulpal floor depth in composite preps
1.5mm, no greater than 2.5mm
what are the bevels we would do in a composite prep
- lingual wall bevel
- gingival bevel
- axial- pulpal line angle bevel
when do you not bevel the gingival floor
if it is in dentin or cementum
what instruments should you use for flare on facial
7902 bur and hatchet
what walls should be converged and diverged in composite prep
- dovetails diverged
- slightly converged or parallel occlusal walls
what instruments should you use to finish a composite prep
- use flame shaped diamond bur
- use hatchet on proximal walls
what should the composite prep be free of before restoring
debris, moisture, blood and saliva
what are the additional steps to prepare for tooth bonding in composite restorations
- etch (and rinse), bond agent placement (gentle, dry, light cure), composite placed incrementally, light cure each increment
why is it more challenging to establish contact with composite
- composite does not displace the matrix band like amalgam
- shrinkage occurs as you light cure
- different type of matrix may help counteract this issue
what is complete etch
- place etch on enamel first followed by dentin
- etch enamel 20-30 seconds
- etch dentin 15-20 seconds
- rinse and gently air dry
- typically only done with total etch and universal bond agents
what is selective etch
- etch enamel only
- 20-30 seconds
- rinse and air dry
- can only be done with certain bond agents
what bond agents can be used with selective etch
universal (what we use in clinic and lab) and self etch types
what would give you clear evidence of etched enamel
whitish etched enamel surface
what do you do if the enamel or dentin is contaminate with saliva when etching
re etch for 10 seconds, wash, dry apply bonding/primer agent, cure and continue
what happens if you dessicate the dentin
collapse of collagen layer and reduced bond strengths
how do you apply bond agent
- gently push bond into tooth
- brush on thin layer
- avoid letting it pool in prep
- gently blow air to thin bond agent and evaporate solvent
- cure 20 seconds
what is usually the solvent in bond agent
acetone, ethanol or water
where should composite be placed first
- first layer of composite in the proximal box to a depth of 1 mm
- some use flowable for first layer
- adapt well into prep and against the matrix band with a small condenser
- cure 20 seconds
can you leave flowable uncured and place regular composite on top
yes
what is the most important first increment
at gingival wall
incremements of composite should not exceed:
2 mm
why should increments of composite not exceed 2 mm
minimizes stresses placed on the material and tooth due to polymerization shrinkage
- could be a factor in post op sensitivity
what instrument should yo use to form the final anatomy on a composite prep
plastic instrument
marginal ridge in a composite restoration should be _____
rounded , not flat
what happens if the marginal ridge is rounded in composite restoration
it shreds floss
what do you do in the final cure for composite
- remove the matrix band
- cure the restoration from the buccal and lingual for 20 seconds
how are voids created in composite restorations
- composite can stick to an instrument and upon pulling back a void is created
- when injecting material, lifting the syring may cause a tug back and create a void
- consider using flowable composite in the box if you cant place composite without creating a void
what are the light considerations when placing composite
- be careful to avoid shining directly on resin while you work - overhead and loupes
- make sure orange protective light is blocking your view of the cure
what do finishing and polishing composite do
- removes the oxygen inhibited layer
- establish anatomy/ final shape
- ensures a smooth surface
what does a smooth surface prevent in composite restorations
- staining
- recurrent caries
what are instruments used for finishing composite
- plastic/composite instrument
- optrasculpt
- esthetic trimming carbides
when are esthetic trimming carbides used
to finish and refine prior to polishing
what instruments are used to finish proximal walls
- discs
- flame shaped carbide
when can you polish composite and why
after finishing because if it is left scratchy the polishing paste will stick in irregularities and make it look worse
what should you do after composite restoration is complete
- remove rubber dam
- compare occlusion to adjacent tooth
- check occlusion with articulating paper
- assess contact with floss
when should polishing of composite be done
same day that it is placed
what does proper finishing and polishing do
- increases longevity of restorations
- improved marginal integrity
- plaque resistant surfaces
- improves esthetics
- improved contours
- undetectable margins
- healthier gingiva
