Study your flashcards anywhere!

Download the official Cram app for free >

  • Shuffle
    Toggle On
    Toggle Off
  • Alphabetize
    Toggle On
    Toggle Off
  • Front First
    Toggle On
    Toggle Off
  • Both Sides
    Toggle On
    Toggle Off
  • Read
    Toggle On
    Toggle Off

How to study your flashcards.

Right/Left arrow keys: Navigate between flashcards.right arrow keyleft arrow key

Up/Down arrow keys: Flip the card between the front and back.down keyup key

H key: Show hint (3rd side).h key

A key: Read text to speech.a key


Play button


Play button




Click to flip

289 Cards in this Set

  • Front
  • Back
What is the ranking order from high to low F- release and F- recharge (same) of theses cements resin-modifies glass ionomer, compomer, glass ionomer, composite resin
glass ionomer, resin-modified glass ionomer, compomer, composite resin
rank the cements from high to low for strength and wear resistance (same)
composite resin, compomer, resin-modified glass-ionomer, glass ionomer
Which cement has high CTE and shrinkage
composite resin
Chich cement has CTE=Tooth
glass ionomer
What cement has a 2 component system
glass ionomer
What cement has a 1 component system
composite resin
these are specific uses of what: cementation (Type 1) intermediate restoration (Type II) especially in high caries risk pt, base or liner (Type III) pit and fissure sealant, ortho adhesive, core build up
glass ionomer cement
What cement has this powder: CaF aluminosilicate glass (particle size 15-50 um depending on type/application) made by fusing components at 1100-1500C also contain La, Ba, Sr, and Zn oxides for radiopacity
glass ionomer cement
another name for glass ionomer cement
polyalkenoate cemnt
What cemnt has this liquid- originally polyacrylic acid in water (40-50 conc) now co-polymer of polyacrylic acid with itaconic, maleic or tricarboxylaic acids
glass ionomer cement
Which liquid component of glass ionomer increase reactivity, reduces visosity, and reduces tendency for gelation
what is added to liquid compont of glass ionomer is added to improve handling characteristics and increase working time, but results in shorter setting time
tartaric acid
in the setting rxn of glass ionomer cement acid etches surface of glass particles to leach what ions in aqueous medium
Ca, Al, Na, F ions
in the setting rxn of glass ionomer cements what 2 ions react to form cross-linked gel matrix surrounding partially-reacted particles
Ca and Al
What 2 ions of the settign rxn of glass ionomer are not involved in cross-linking
Na and F
How does the cross linking phase of glass ionomer mature?
Water is critical for setting of glass ionomer cement describe why
loss of water will dessicate matrix, contamination with water will dissolve matrix-forming ions
the glass ionomer setting rxn is what acid-base rxn
polyacrylic acid + water + reactive glass=acid-cross-linked by metal ions
What bondig is formed by the donation of a pair of electrons from 2 or more atoms to a metal ion, forming a ring coordination complex
chelation bonding
What type of chemical bonding is involved with glass ionomer cement
chelation bonding
glass ionomer have acidic pH on _____, the cement is ____ acidic
setting, more
The pulpal response of glass ionomer is more or lass than ZOE but more or less than Zn phosphate
more, less
glass ionomer have what appearance
glass ionomer have potential for REDUCING OR INCREASING secondary decay by Fl- release, specially in hgigh caries risk pts
glass ionomer bond higher to dentin or enamel
What are the advantages of glass ionomer cement
chemical bond to tooth, well-retained, Fl-release initially high, but decrease to 10% of original after 1 mo, coefficient of thermal expansion similar to that of tooth structure, no polymerization shrinkage, some mechanical prop similar to those of dentin, similar compressive strength, higher diametral strength and greater resistance to disintegration that zinc properties
What is the solubility of glass ionomer
Are glass ionomer relatively biocompatible
are glass ionomer packable
yes, higher compressive and flexural strengths than traditional
how is glass ionomer cured
chemically useful in atramatic restorative technique
Can glass ionomer be used with bonding agents
yes, but fl- release is reduced under bonding agents
do GI have polymerize shrinkage
The mechanical properties of GI are similar to what tooth structure
What cement is brittle
glass ionomer (GI)
Describe the compressive and tensile strengths, fracture toughness, and resistance to wear of GI
Glass ionomer has ____ the elastic modulus of zinc phosphate
What is the color/appearance of glass ionomer
opaque appearce of set restorative material
Glass ionomers need good moisture control, they are susceptible to desiccation and to moisture contamination until what?
matrix matures
How can you protect the margins of GI cement
using varnish or bonding agent
GI have post-operative sensitivity, especialy if what?
What is a limitation of the strength of GI cements
takes time to reach
Describe the handling characteristics of GI cements
fair-poor handling
GI cements are not recommended for cementing what
ceramic restorations, b/c low elastic modulus
The low elastic modulus of GI cements could cause the restoration to develop greater what on occlusal loading
tensile stress
What cement is used for permanent luting, core build-up, ortho bonding, class III, V, in high risk pt and abfraction lesions
Resin-modified glass ionomer cement (hybrid ionomer)
What cement has radiopaque fluoroaluminosilicate glass and catalyst in its powder
hybrid ionomer, (resin-modified glass ionomer)
What cement has modified polycarboxylic acid containing methacrylate and HEMA, photo-initiator in its liquid component
hybrid ionomer
Resin-modified GI have what bond to tooth thats well retained
how is resin modified GI cured
light activated
Comare resin modified GI to traditional GI
higher compressive strength, higher bond strength, less moisture sensitive, improved wear resistance
Describe the handling charactistics of modified hybrid GI
describe the film thickness of resin-modifed GI
low approx 25um
compare the technique sensitivity of resin-modified GI and resin cements
resin modified less sensitive than resin cement
Does resin-modified GI or trad GI release more Fl-
trad GI
Resin-modified GI should not be used under most all-ceremic crowns, why?
coefficient of thermal expansion higher than that of tooth structure
immediately after resin-modified is placed need to what?
control moisture, susceptible to desiccation
Does resin-modified polymerizaion shrink
if over dried resin-modified Gi iwll have what
post-op sensitivity
resin modified Gi is brittle
What is a composite resin and glass ionomer
what is poly-acid modified composite resin
What cement is for low stress-bearing restorations such as class III and V chemical cured or dual-cured
What compomer materials are used in class I and II in adults and kids
compomer can also be used as
luting cement, base/liner
What cement is commonly used in pediatric and geriatic pts
What contain carboxylic-acid modified dimethacrylate, hydrophilic primers, fluoro-alumino-silicate glass, fillers, photoinitiator
compomers need ___-____ polymerization first, ____-_____ reaction only after exposure to H2O
light-activated, acid-base
compomer should be bonded using what since compomers do not chem bond to teeth
bonding agent
What type of systems usually have low bond strength to compomers
6th generation type I systems
When should bonding agents not be used with compomers
on primary teeth
How should compomer be placed
When shoulld excess compomer be removed
after gel state reached b/4 polymerization
The Fl- release of compomer relates how to glass ionomer and resin-modified GI
What are the advantages of compomer
one-paste restorative system, fast setting time, relatively insoluble
what are limitation of compomer
not recharged with Fl- Tx or toothpase as much as GI or RMGI, Fl- release decreases within 30 days, and is accelerated by acids or salivary amylases, sensitive to light and moisute, poly shrinkate of 2-2.5 vol%
in compomers water sorption=what
slight expansion
how compomer overall mechanical prop relate to composite resins
te coefficient of thermal expansion of compomer is LOWER/HIGHER than tooth structure
Can compomer be used for pulp capping or core build ups under all ceremic crowns
Describe the color stability over extended periods is what
moderate to poor limited # shades 12
How does compomer polish compaed to microfilled composite resin
less polishable due to larger particles
What cements are designed to provide thermal protection to pulp, provide mechanical support for restorations
high-strength cement bases
What can be made from glass or hybrid ionomer or reinforced ZOE
high-strength cement bases
do high strength cement bases have high or low compressive strength
What are usually calcium hydroxide, glass ionomer, ZOE and serve as a barrir against chem irritation
low strength cement bases
What is used for temp/provisional (type I) and intermediate (type II) luting cemnts, temp/provisional restorations and bases (type III), liner (Type IV)
zinc oxide eugenol ZOE
What has powder: 69% zinc oxide 29% rosin, ZN acetate
ZOE cement
What is the liquid in ZOE
eugenol and other oils
What cement is sedative, palliative effect on pulp, form an excellent seal, should not be used prior to placement of restorative/bonding resins (inhibit poly)
What is used for base, filling, cementation
reinforced and improvedZOE
What contains 80% zinc oxide coated with carboxylic acid and 20-40% acrylic resin particles as powder, and eugenol for liquid
reinforced ZOE
What cement contains 70% zinc oxide and 30% alumina as powder and 37.5% eugenola nd 62.5 ortho-ethoxybenzoic acid (EBA) as liquid
improved ZOE
what is nogenol
no eugenol-same powder as improved ZOE only EBA as liquid
What is used for cementation of veneers, restorations, temp crown
resin cements acrylic
What contains Powder: methyl methacrylate polymer or copolymer containing benzoyl peroxide, liquid: methyl methacrylate monomer with amine accelerator
resin cements acrylic
What resin cement contains 4-META adhesion promoter added to methyl methacrylate monomer, and contains tributyl boron initiator
modified acrylic resin cements
Which resin cement is used for cemention of crowns, bridges, inlays and veneers, mainly composed of bis-GMA and are available as chem-cured, lt-cured, or dual cured, some comp similar to dentin bonding resins
dimethacrylate cements
What are the advantages of resin cements
high strength and toughness, fracture toughness higher than all other cements, good retention particularly under all cement restorations, low oral solubility
disadvantages of resin cement
elastic modulus lower than zinc phosphate, some cements have poor handling characteristics, poly shrinkage and elakage, higher film thickness, technique sensitive materials, pulp sensitivity, excess cement should be removed immediatly after seating the restoration and not be delayed after polymerization
What is ued for a liner, direct and indirect pulp capping, temp filling of inlay prep, base
calcium hydroxide cement
These are the principle components of what: liner: Ca(OH)2 and thickening agent in solvent, solvent evaporates and leaves ting film of Ca(OH)2
calcium hydroxide cement
These are what in calcium hydroxide cement: Ca tungstate, Ca phosphate, ZnO in glycol salicylate
base paste
These are what in calcium hydroxide: Ca hydroxide, ZnO, Zn stearate
catalyst paste
What biological effect does calcium hydroxide have on pulp
stimulate formation of reparative dentin
What is contains natural gum (copal), rosin or synthetic resin in an organic solvent (acetone, chloroform, ether)
cavity varnish
What has the purpose to protect dentin from chem irritation, such as zinc phosphate cement pH and to minimize microleakage at margins of newly plaed dental amalgams
cavity varnish
Should cavity varnish be used under restorative resins or GI
gingival tissue pack
Periodontal dressing
ZOE, Zinc Oxide prep
root canal sealer:
glass ionomer, ZOE, resin cements
cemetation of ortho brackets and bands
resin cements, bonding agents, hybrid ionomer, Zn phosphate
What cement is designed for retaining crowns, bridges, inlays, onlays,, posts, and pins on prepared teeth and ortho appliances to teeth
luting cements
Lutting cements work by filling in spaces between what 2 things
prepared tooth and the restoration
Some cements made of resin also contain a what for bonding to teeth
bonding resin
What cements designed to cover dentin, protect pulp, and provide temporary function while a permanent restoration is being fabricated
temporary and intermediate filling materials and tempoary luting cements
What cements designed to provide thermal protection (insulation) and encourage recovery of an injured pulp
cement bases
What material is used to protect dentin and pulp tissues from irritant attack, tey are not thermally insulating
Classification of cements
chem composition, function
cements chemical composition is mostly what combo
What may be modified by manufacturer for specific properties , handling characteristics and intended use
these list cements by what: as a luting cement, base, liner, temporary filling material, temp luting cement
What 2 things don't have acid-base rxn
calcium hydroxide, and resin cements
in the acid-base rxn what is the liquid portion
acidic solution
The powder of acid-base rxn contains glass or metallic oxides and tha _____ pH
Resin cements have what rxn
What has physicochemical mechanism of carie inhibition
After the upatke of ____ by apatite, formation of less soluable, acid-resistant phase (fluorapatite)
caries inhibition invovles dissolution of unbound Fl- which results in what balance theory
remineralization-demineralization balance theory
Fl- treated enamel has ____ surface E, hence probably retains less plaque
What are the anticariogenic properiteis of Fl-
physiochemical mechanism of caries, biologic mechanism of careis inhibition, Fl- in dental materials, Fl- recharging
What is the inhibition of carb metabolism of acidogenic plaque microflora by Fl- that accumulates in dental plaque
biologic mechanism of caries inhibition
What is silicate, glass inonmer, and silicophosphate cements, compomers, resins, sealants, varnishes, gum, toothpaste
Fl- in dental materials
What is uptake of F- ions existing restorations containing Fl- for re-release
Fl- recharging
speicific use for silicate cements
anterior restorations
What is the glass of silicate cement made of?
SiO2, Al2O3
what cement includes Fl- and Ca+ componens such as NaF, CaF2, NaAiF6, Ca(H2PO4), H2O, CaO that act as fluxes
silicate cements
What are compounds that lower the fusing temp
fluxes, silicate cements fuse at 1400C
During setting of which cement is Ca2, Al3, F- ions are leached by acid attach and form phosphate in cement matrix
silicate cements
what is well known from numerous clinical and in vitro studies, but the precise mechanism of action is not know
anticariogenic potential of silicate cements
areas adjacent to silicate cements are less likely to get secondary caries, because
Fl- releasing restorations
What is the advantage of silicate cement
Fl- release
Ehat are the disadvantages of silicate cement
high solubility rate, degradation, loss of contour, short restoration life span, brittle
What cements are desgned for retaining crowns, onlays, bridges, ect, on prepared teeth
type I cements
What cements work by filling in spaces between the prepared tooth and the restoration or appliance and then hardening
luting cements
How do you select dental cements
physical and biological properties, handling characteristics, cost
What are some handling characteristics.
work and setting time, ease of manipulation, pre-dispensed doses, ease of removal of excess material
What is the weakest link in the tooth-cement restoration interface
cement layer
What are factors influenceing retention of cemented restoration
film thickness, tensil strength, dimensional changes, chemically bonded
What film thickness has fewer flaws
thinner films
What of a cement should be high as should be compressive and shear strengths and fracture toughness
tensile strength
What changes during setting should be minimized by proper isolation and protection
What cements may increase retention
What cement is used for final cementation, high-strength base
zinc phosphate cement
What cement has the power: 90% zinc oxide, 10% magnesium oxide are sintered between 1000-1400 C and then ground, smaller size particles set faster
zinc phosphate cement
What cement has the liquid: phosphoric acid, water ( 33 vol%), aluminum and zinc phosphates
zinc phoshpate cement
with zinc phosphate cement what protection is necessary because pH of the liquid is initially strongly acidic
pulpal protection
what is the initial pH of zinc phosphate then what does it rise to?
starts at 2 and rises to 5.5 within 24 hrs
What must be fluid enough to form 25um or less film thickness, and 0.2 wt% max solubility and disintegration in water
Type 1 cement- zinc phosphate cement
the setting time for Type 1 zinc phosphate cemnent is between what at 30C and 100% humidity using 4.5 N Gillmore needle
5-9 min
What should the compressive strength after 24hrs of type 1 zinc phosphate cement
68.7 MPa
Setting time of zinc phosphate cement can be altered by what
changing powder-liquid ratio (not recommended), rate of powder incorporation, spatulation time, temp of mixing slap (highly recommended)
What should be removed after setting is complete of zinc phosphate (excess cement)
What cement has uses for restorative and ortho comentation, base cement
zinc polycarboxylate
What cement has this powder: zinc oxide, sometimes magnesium, aluminum and bismouth oxies, small amts of SnF
zinc polycarboxylate
What is added to powder of zinc polycarboxylate that modify setting time, enhance manipulative prop and increase strength
What cement has this liquid: polyacrylic acid in water or co-polymer of polyacrylic acid (32-42%) with unsaturated carboxylic acids such as itaconic acid, the comecular wt of poly acids is 30,000-50,000
zinc polycarboxylate
What was pseudoplastic in nature, film thickness <or equal to 25um
manipulation of zinc polycarboxylate cement
Is the working time of zinc polycarboxylate greater or lesser than that of zinc phosplate
lesser 2.5 min vs 5min
What of zinc polycarboxylate indicates prolonged mixing time and that insufficient number of carboxyl groups are abailable to bod to tooth
dull, tacky appearance
what cement has same uses as zinc phosphate
ainc silicophosphate cement
What is the powder andliquid of zinc silicophosphate
powder: silicate glass, zinc oxide, liquid phosphoric acid
What cement is translucent, esthetically better than zinc phosphate and had superior properities, releases Fl-
zinc silicophosphate
When conditioning the dentin what are the possible Tx to the smear layer
leave intact, completely remove, modify layer, remove and replace with something else
What are possible choices for acids to remove smear layer
EDTA, phosphoric acid, citric acid, maleic acid, polyacrylic acid
When conditioning the dentin surface, what are considerations for smear layer removal
alteration of dentin permeability, demineralization of dentin surface, denaturation of collagen, alteration in surface wttability retention of exposed collagen in "fluffy" state
conditioning dentin increases surface area by how much
acid etching of dentin once frowned upon, now known that as long as margin is totally sealed the pulp rxn is very ____
What is the capacity of the dentin helps reduce the acidity of the etchant
when both enamel and dentin are etched
total etch technique
What is the purpose of acid etch of dentin
demineralize only top few microns (3-5um) of dentin, removed smear layer and leaves behind collagen fibrils
etching dentin, ___ vigorous acid action is desired
acid etch eith ___ concentration of phosphoric acid (10), or a _____ duration of etching with 37% phosphoric acid (15-30) or a different type of acid
lower concentation, shorter duration
viscosity of etchants, what type of etchant contain colloidal silica or polymer beads in acid to help retain etchant locally, applied with brush or syringe
why should gel etchant be agitated occasionally
to bring fresh etchant to tooth surface, uniform etching
do you rinse gel etchant
yes with water
What type of etchant tends to flow and are difficult to maintain in position, penetrate pits and fissures better
In dentin, acid dissolves ____ phase and exposes______
mineral phase, exposes collagen
What happens to collagen after etching, washing and drying, which prevents bonding resin from penetrating the fibril
collapse collagen
priming the dentin surface, in order fro the bonding resins to _____ the collagen exposed during demineralization, collagen fibrils must be resuspended. This is accomplished using ___ _____ techiniques which act to fluff up the collagen fibrils in an aqueous medium
infiltrate, wet bonding
What has a hydrophilic monomers that are applied in an organic solvent base
What in primer is to displace water and to stiffen the suspended collagen so that max monomer pentration occurs around exposed collagen and into demineralized spaces
What monomer is typically the solvent
hydroxyethylmethacrylate (HEMA)
What infiltrates into the exposed and expanded collagen network and creates a zone which has properties of both a polymer and a tough, resilient protein, collagen
adhesive resin
What has properties of both a polymer and a touh resilient protein collagen
hybrid layer
How thick does hybrid layer need to be to acheive high bond strength
what is typically placed over hybrid layer and light cured
adhesive resin
What polymerizes not only the adhesive layer, but also the underlying HEMA, locking these resins mechanically tot he tooth structure
curing the resin cause what type of bond betwen resin and tooth structure
what is added over conditioned and primed dentin thus bonding to underlying resins
restorative resin
The adhesive resins have sufficient # of ______ groups exposed on their outer surface so that _____ bondign will occur b/t adhesive layer and restorative resin
methacylate, covalent
Most/all bonding to dentin is
micromechanical of hybrid layer
little evidence of formation of true ___ bonds to either colagen or to hydroxyapatite
type of bond b/t resin and resin
developed in 70's single component bifuctional coupling resins that were methacrylate-based, were supposed to bond to calcium (chelation bond) but left smear layer untoughted, 2Mpa stength
1st gen
who develped 1st generation
Drs. buonocore and bowen
what generation is phosphonate-based resins containg Bis-GMA, developed 1980's proved good enamel bonding resins, 8Mpa
2nd gen
What generation is oxalate-based resin (NTG-GMA, PMDM) mid to late 1980's by Dr. Bowen, 2 component systems consisting of conditioner, primer, and adhesive resin, that modify or selectivly remove smear lyer 8-15 MPa
3rd gen
What generation is hydrophilic primers and resins developed for use with the total-etch technique and wet bonding in the early 90's a hybrid layer created, bond to teeth, resin, procelain, metal, low psot-operative sensitivity 17-25 MPa
4th generation
what generation was developed in mid 90's. combine primer and adhesive in 1 bottle, exhibit lower bond strengths than 4th resins and more sensitivity, more technique sensitivity 15-25 Mpa
5th generation
what generation was developed in late 90's , combine etchant, primer, and adhesive resin in 1 bottle, but are multistep, have strength similar to 5th generation, no results long term studies, water solvent 18-23 MPa
6th generation
is bond strength true predictors of success
What 7th generation was developed in 2002, moderatly acidic self etching, no mix adhesive resin dispensed in single doses, or in 1 bottle, dissolves smear layer, does not need to be rinsed, few shor term clinical studies, contains UDMA, 2-META, acetone, water, gluteraldehyde, camphorquinone, can disinfect and desensitize, bond to amalgam and ceremic, and can be polymerixed by LED, halogen, PAC lts, not to be used with self-curing cements/materials18-28MPa
iBond (Heraeus Kulzer)
What componet allows bond to amalgam and ceremic
what 7th generation was developed in 2004, contain phosphoric acid, ester monomer, 4-MET, UDMA, TEGDMA, acetone, water, initiators, and filler particles dispensed in 1 bottle or unit dose dissolves smear layer, requires short burst of high pressure air, shorter aplication, and cure time, insensitive to level of wetness, and forms a non-coventional interface with the dentin, can be used with dual cure cements and can be polymerized by LED, halogen, PAC lts
G-Bond (GC Corp)
What is the non-conventional interface formed by G-bond
nano intaeraction zone or NIZ
What 7th generation was developed in 2005, contain methacrylate resins, PENTA, photoinitiators, stabilizers, acetone, cetylamine hydrofluoride, water, and filler particles dispensed in single dose or in bottle, releases Fl- can polymerize by most lts, should no be used with dual cure cements, uncut enamel, as a dired pulp capping material, or with phosphoric acid tooth conditioners
Xeno IV Dentsply/Caulk
What are solvents used in bonding agents
acetone, ethanol/water
What solvent drives water away, better wettability and penetration of tubules, evaporates quickly after dispensing, multiple coats needed, sensitive to dentin wetness
What solvet must be dried completely, needs extra dry time, evaoprates less quickly, less sensitve to dentin wetness, thin film formed, requires figorous rubbing of material
What solvent is needed for ionization of acidic resin monomer, slower evaporation, so longer dry time, can interfere with polymerization, not sensitive to wetness of dentin
water can interfere wit polymerization, so unpolymerized monomer may continue to ____ dentin and result in _____ bond strength
etch, lower
What solvent needs no drying, single coating, larger film thickness, may lower bond strength
resin based system use the ability of low viscosity resin to penetrate etched enamel, and then polymerize and form a seal against microbial attach
pit and fissure sealant
What are filled or unfilled containing bis-GMA, polyurethanes, or cyanoacrylates athat are light cured or self cured
pit fissure sealant
color of filled and unfilled sealant
filled- opaque/white, unfilled- colorless/transparent
properties of sealants are MORE OR LESS similar to unfilled restorative resins than composite resins
what type of restorations use sealants
preventive resin restorations
What is to arrange in a pattern that gives strength, to connect or fasten together
What if the force causing two similar materials to attach to one another when brought into intimate contact
What is the force causing two dissimilar materials to attach
What is secondary bonds (hydrogen bonding, van der Waal's forces)
What are primary bonds (monomolecular layer attached by covalent bonding)
To "fill the gap" formed between 2 surfaces what is used?
The adhesion substance comes into much more intimate contact with the adherend, DECREASING OR INCREASING opportunity for more adhesion
What is the surface to be bonded
What form is the adhesive usually in, to provide the greatest surface coverage
What is a poorly adherent layer of ground dentin produced by cutting dentin
smear layer
What is an acidic agent that dissolves inorganic dentin components, creating a collagen network that permits infiltrateion by adhesive resin
dentin conditioner
dentin conditioner is commonly called
What is hydrophilic, low-viscosity resin that promotes bonding to dentin
What intermediate layer of primer, adhesive rsin, collagen, and dentin produced by acid-etching of dentin and resin infiltration into conditioned dentin
hybrid layer
Dental bonding to composite resin advantages (5)
bond resins to tooth structure, decrease resin polymerization shrinkage, minimize marginal gap formation and subsequent microleakage, conservation of tooth tissue, reinforcement of weakened tooth structure
What are the disadvantages of dental bonding to composite resin
technique sensitivity, not chemically bonded to tooth structure, postoperative sensititivity, can be contaminated by saliva, eugenol-containing materials, caries detectors, hemostatics, 02 from bleaching agents inhibits curing
What would have these characteristics: have high bond strength to enamel and dentin, form an immediate and durable bond, prevent the ingress of bacteria, be safe to use, be simple to use, be able to bond to restorative materials.
ideal dental bonding agent
What provides means for mechanical attaching resin to enamel
Is acid etch more reactive to enamel rods cut parallel or perpendicular tot he tooth surface
What cleanses adherent proteins, pellicle and debris off the tooth, and increases surface energy to approximately twice, enabling better wetting by bonding adhesive?
Does acid etch INCREASE OR DECREASE the surface roughness of enamel and therefore area available for bonding
What acid etch is 30-50%, most common 37%, concentrations > 50% precipitate monocalcium phosphate monohydrate which prevents further disolution?
phosphoric acid
What are other acid etches
nitric acid, citric acid, maleic acid
Etching of enamel, perferential dissolution of center ______ or peripherial area ______ of enamel rods
Type I, type II
What are combinations of unfilled, low viscosity dimethacrylates (bis-GMA and/or TEGDMA) that were hydrophobic in nature
enamel bonding agens
Enamel bonding agens where shown to have what type of bonding to enamel by the formation of resin tages 10-20 um deep within etching enamel rods
micromechanical bonding
Enamel bonding agents were replaced by what ehn etching of dentin and enamel was accepted (initially only enaeml etching was done)
dentin bonding agents
What is the hydorphobic and hydorphilic monomer of bonding agents attracted to?
hydrophobic- resin
The molecules for bonding to teeth are M-R-X, what do they stand for?
M- a methacrylate group capable of bonding to the overlying composite, R- spacer, X- functional group designed to react with organic or inorganic portion of tooth
What is bonding to inorganic component?
chelation bonding
What is a bond formed by the donation of a pair of electrons from 2 or more atoms to a metal ion, forming a ring coordination complex?
chelation bonding
Chelation is also common in monomer specifically designed to bond to what?
These are what: phosphonated esters (scotchobond, Panavia), PETA (Probond), NTG-GMA (Tenure), PMDM (all bond), 4-Meta (amalgambond)
chelaiton bonding, bonding to the inorganic component
Organic bonding, bonds to what?
What contains only a small portion of bondable amino acids
What organic components react with the protein
gluteraldehyde and HEMA
What is a methacrylate group "grafted" onto the collagen strand
Atoms at the surface of the adherend have a HIGHER/LOWER energy state than do those within the bulk of the solid due to non uniform forces acting upon them
HIGHER, condition leads to forced named surface E
Atoms at a surface of a liquid have a HIGHER/LOWER energy state than do those within the bulk of the liquid due to non-uniform forces acting uponw them
HIGHER, surface tension
the interaction of adhesive with adherend is to obtain successful bonding, the adhesive must _____ the surface of the adherend
Interaction of adhesive with adherend, if the surface E of the solid is ____ than the surface tension of the adhesive, the adhesive will NOT wet the solid surface
interaction of adhesive with adherend, if the surface E of the solid is _____ than the surface tension of the adhesive, the adhesive will wet (cover) the solid surface.
What is a measure of the ability of an adhesive to wet a solid surface
contact angle
if the contact angle is high adhesion will be what and is surface tension GREATER/LESSER than surface E
adhesion poor, surface tension greater than surface E
Describe the adhesion and relationship of surface E to surace tension when contact angle is low
adhesion- good, surface E is greater than surface tension
What clinical factors affect potential for wettability
chemical nature of the components, cleanliness of the adherend, penetration of surface, contamination, incomplete removal
Describe chemical nature of the components
enamel and dentin in natural vs. etched (higher E) states
Describe cleanliness of teh adherend
retained protein film, smear layer, saliva contamination
Describe penetration of surface
liquid adhersives
Describe clinical contaminaitons
water, saliva
Deacribe the clinical factor, incomplete removal
of etchant or dissolved, demineralized tooth structure
What is the bond strength of enamel
minimum retentive strength of etched enamel to bonding resin 20 MPa or 2,900 psi
describe range of dentin bond strengths
15-25 MPa
The goal of dentin bonding is to attain bond strends ______ to, or _____ than those of etched enamel
equivalent, higher
dentin bond strengths have been acheived in laboraory, but testing values are very susceptible to what?
6 facorts affecting bond strength
tooth vitality, direct tooth is sectioned: M-D, B-L, or occlusal, tooth age- sclerotic dentin, depth of cut into dentin- near DEJ, mid, or near pulp, tooth storage conditions: duration in storage, storage solution, method od bonding testing
Describe the compositon of dentin and enamel
enamel- organic 2, inorganic 92, water 6, Dentin- organin 33, inorganic 45, water 22
Forces during polymerization shrinkage are quite high (give values) and can ______ the bond strength of tooth to resin.
10-17 MPa or 1500-2500 psi, compromise
To minimize stresses at the tooth/resin interface, the C-factor should be as ____ as possible
What is the ratio of bonded to the unbonded surface areas
C-factor, configuration factor
rank from high to low the leakage potential for a square 1mm deep, square 1.5 mm deep, or round 1mm deep
square 1.5mm, square 1mm, round 1mm