Operative- ABGD Flashcards
What is the bactericidal composition of SDF?
38% fluoride
25% silver particles
How many ppm of Fl are in SDF?
44,800 ppm
How is SDF bactericidal?
“Zombie” effect. silver particles remain in the dead bacteria which kills the consuming bacteria
How much fluoride is in Fl Varnish?
5% NaF, 22,600ppm
How much fluoride is in rx toothpaste?
1.1% NaF, 5,000ppm
How much fluoride is in rx Fl rinse?
0.02% Neutral Sodium Fluoride 900ppm
prevident
how much fluoride is in OTC toothpaste?
0.12%: 1000ppm
0.25% NaF (sensodyne) : 1100
What are the advantages and disadvantages of calcium silicates compared to CaOH?
Advantage: (ie MTA)
increased antibacterial properties
increased dentin bridge formation
good dentinal seal
Disadvantage:
longer setting time
costlier than CaOH
What are the different types of ceramics- give examples
Glass:
- feldspathic- vitamark II
-Leucite reinforced: empress cad
-LiDi: emax cad
Oxide ceramics:
-Alumina- InCeram
-Zirconia: Zircad
What are the ways to pretreat restorative materials?
Air Abrasion with 50micron particles— metal alloys and zirconia
Acid etch with HF: glass ceramics
Tribochemical Silica Coating
- resin core materials
Zirconia?
What is MDP?
Phosphate methacrylate alloy primer that bond to non-precious metals and oxide ceramics.
MDP is an organic ester which can chemically bind to the oxide layer created on the metal surface through covalent bonds and also mechanical retention to the sandblasted surface. Among phosphate monomers, MDP seems to be more suitable for bonding to base metal alloys and provides greater bond strength.
What is Silane
A bifunctional molecule ceramic primer that bonds silica-based glass ceramics
what is VBATDT
Sulfide methacrylate alloy primer that bonds to precious metals
What are the ideal properties of a post?
max protection of the root from fx
max retention within rt
max retention of the core and crown
max protection of the crown marginal seal from leakage
pleasing esthetics
high radiographic visibinlity
retreviable
biocompatible
Explain the 4th gen bonding agents? What is an example?
3 step, E&R
Etch, rinse, prime, bond
Phosphoric acid
Hydrophilic primer (ethanol, acetone solvent)
Hydrophobic adhesive (non-solvated resin)
Example: Optibond FL
Explain the 5th gen bonding agents? What is an example?
2 step E&R
Etch, rinse, Prime/bond
Phosphoric acid
Hydrophilic primer (ethanol, acetone solvent) with a hydrophobic bonding resin
Optibond Solo Plus
Explain the 6th gen bonding agents? What is an example
2 step, Etch and dry OR 3 step with selective etch
(Etch/prime, and bond)
selective etch =. 3 step
Self etch with acidic primer
Hydrophobic filled bonding resin coating
excellent bond to dentin
Less sensitivity
Ex: clearfil SE protect or Optibond XR
What can occur if the solvent is not completely evaporated
unevaporated solvent will eventually be replaced by water which leads to hydrolysis of resin components and creates nanoleakage
Whatare dentinal collagen vunerable to and what else activates when exposed to etch and rinse procedures?
high vulnerable to hydrolytic and enzymatic degradation processes
Demineralization of dentin turns on MMPs (matrix metalloproteinases)
Explain 7th generation dentin bonding agents and give an example
1 step “one bottle”
etch/prime/bond
self etch
acidic primer with multiple functional monomers
poor performance clinically
Ex: optibond all-in-one
Explain 8th gen bond and give an example
1 step “one bottle”
etch/prime/bond
bonds to tooth and dental materials
multi-mode= etch and rinse, self etch, and selective etch
Scotchbond universal
What is the composition of enamel?
90% hydroxyapatite (inorganic)
10% water and organic
what is the sensitivity and specificity
what is preferred in dentistry
sensitivity- true positives- tests for who has the d.z.
specificity- true negatives - test for who doesn’t have the dz.
better to have specificity to avoid over treating
High sensitivity = more false positives, but also fewer false negatives
High specificity = more false negatives, few false positives
What is the composition of dentin
50% hydryapatitie
30% collagen
20% water
What is the diagnodent and does it have high sensitivity or specificity?
uses laser fluorescence to aid in the detection of caries within the tooth structure
sensitivity = over tx
Is the visual method for caries detection viable?
yes
good accuracy and high specificity
What are the pathologic and protective factors for teeth in the caries process?
Pathologic: BAD
bad bacteria
absence of saliva
destructive habits
Protective: SAFE
Saliva and sealants
antimicrobials
fluoride
effective lifestyle
What is ICON?
low viscosity resin infiltration of for the tx of early lesions interproximal up to D1 (outer 1/3 od dentin)
good for white spot lesions
contraindicated in D2 or greater
Uses HF to etch teeth
How deep can ICON penetrate? Is it more effective in active or arrested lesions?
450 microns
best in shallow, active lesions
How strong is emax and what is the recommended thickness?
1mm- if bonding
500MPa
What is C-factor and what are the implications in restoring with composite
bonded surfaces/#unbonded surface
lower C factor is better
Class V is lower than Class I
helps to understand polymerization shrinkage and sensitivity
if there are more bonded surfaces, then there is more tension pulling away from multiple surfaces and shrinking thus, more sensitivity
What is the cervical margin elevation, is it viable?
GI or composite on margin to increase coronally.
yes, 95% survival rate, but ≤2mm from bony crest = greater BOP
What is the longevity of veneers?
10 years- 95%
What is the most critical factor in a veneers success?
Enamel
10x greater failure risk when bonded to dentin instead of enamel
If we wanted to bond to Zirconia do we etch?
How do you bond to zirconia?
no. Zirconia is a polycrystalline solid and has no glass
50micron aluminum oxide air abrasion of intaglio
use MONOBOND PLUS ( bifunctional 10-MDP monomer can bond to metal oxide) or ROCATEC (tribochemical silica coating) to bond
What is connector and pontic sizes needed for zirconia?
Anterior: 7mm2
Post: 9mm2
2 pontics: 12mm2
height is most important
What are things to consider with air abraiding zirconia?
% yttria (3, 4, 5, mol)
the one with less tetragonal % might be more detrimental since it does not undergo as much transformation toughening to monoclinic particles
What are the different types of resin cements
Curing
light cure
dual cure
Tx
Esthetic: total etch
adhesive: self etch
self adhesive
What can you tell me about “Universal Adhesives”?
all in one
can be used for E&R, selective etch, and self etch
lower pH, enhancing self etch mode
MDP functional monomer- good for dentin
may include primers for glass and oxide ceramics
IE: scotchbond universal- 8th gen- contains silane but not as effective as separate silane
What is an example of a bioactive resin material?
Activa
Calcium silicate and calcium aluminate materials for an apatite like material on the surface
limited research
have high early failure rates for class I and 2
also: proroot MTA, biodentine, endosequence, ceramir C&B (luting)
How are manufacturers reducing shrinkage in bulk-fill materials?
using “stress-reducing resins”
fragmentation monomer,
Whats the difference between incremental and bulkfill techniques?
Incremental: 2mm then cure, decreased polymerization shrinkage by placing at diagonals with less walls
bulkfill
up to 5mm composite then cure.
larger filler particles, more photoinitiators, increased tramslucency
maybe less voids
What composite do you use and why?
Filtek supreme:
nanofilled composite
Why: good polishability, good esthetics, easy to get, good strength and shades, minimal shrinkage (<1%)
65-75% filled depending on translucency level
good wear
and high fracture strength (350MPa)
omnichroma
technically less good shade match, butmost people don’t notice for molars
supranano spherical
filler 79%
higher polish than filtek
flex strength < filtek
compressive similar to filtek
less wear than filtek
higher shrinkage 1.5%
stain resistance same
not as hard as filtek, but a more consistant cure at 4mm
What is the blue light hazard?
Blue light, 440nm
absorbed by retina and can damage it.
Camphoroquinone 460
What is the ISO standard for minimum output of a curing light
What do most composites recommend for cure?
ISO: 300mW/cm2
Composite: 550mW/cm2
When did the EPA mandate amalgam separators be used by?
2020
What is an amalgam separator and how does it work?
reduce amalgma discharged into water system. removed from waste vaccume system by sedimentation, filtration and ion exchange.
prohibits used of bleach in lines that may dissolve solid mercury when cleaning traps and vacuum lines
What type of amalgam do you use and why?
Contour amalgam- admixed
70% spherical and 30% lathe cut
High copper (28%) to decrease gamma 2 phase and corrosion
great strength and handling
533MPa @ 25 hrs
almost 10 min working time
What kind of curing light do you use and why?
Elipar LED by 3M
uniform distribution
2.1 mm curing depth, easy to hold one to, has sheilding
high intensity: 1200mW/cm2
What is clearfil SE
6th generation bonding system
2 step etch and rinse. can use selective etch
great bond to dentin, less post op sensitivity
Do you use sectional matrix for class 2?
yes, better contours, saves time, more predicable
garrison or V3s
What are some disadvantages of IDS
additional steps
potential incompatibility with impression or temp materials
technique sensitive (remove excess material on enamel margins
What do studies say about IDS?
Lab studies show improved bond strength, fewer gap formations, less bacterial leakage
no difference in post op sensitivity, but 11 yr clinical study shoed that feldspathic veneers with more than 50% dentin exposure had significantly better survival with IDS (96 vs 82%)
The use of filled adhesive resins (low elastic modulus liner) facilitates the clinical and technical aspects of IDS
What do you know about millable ceramic polymer materials?
Example: vita enamic or Lavac Ultra
highly polymerized composite materials that have greater fracture roughness, better edge quality and no sintering
higher debonding for full crowns, because they flex. more suitable for inlays and onlays
What are the risk factors that would lead you to classify somone as moderate or high caries risk
Poor OH
cariogenic diet
exposed roots
enamel defects
multisurface restores
overhangs or open margins
active ortho
cariogenic bact
chemo/rad
eating dioders
disability that prevents good OH
subopitnal Fl
xerostomia
what do you do for high caries risk patients?
OHI
fluoride
eliminate caries
sealants
remineralize incipient
diet counseling
prevident and/or CHX (1 week a month)
xylitol
recall Q3months
moderate risk = 6mo
eval salivary flow
what is the critical pH of enamel?
5.5
