Dental cements 9 Flashcards
terms
ZOPC =zinc oxide phosphate cement •ZOE or ZOEC =zinc oxide eugenol cement •ZPC = zinc polycarboxylate cement •SPC=silicate phosphate cement •RC=resin cement •CC=compomer cement •SC=silicate cement
Classification
1.Clinical criterion
Fixing (luting) -Restoration (fillings) -Base fillings -Pulpal-dentinal protection
Classification
2. Chemical composition criterion
A.Minerals
- Zinc phosphate(ZOP)
- Silicate(SC)–used for restorations, replaced with GIC
- Zinc silicate-phosphate(SPC) combination of properties of ZOPandSC–were used for luting the ceramic restorations and for restorations on the decidual teeth
B. Organic-mineral
Zinc-oxide-eugenol (ZOE) -reinforced ZOE -ZOE modified withEBA (orthoetoxybenzoic acid) -ZOE modified withHV-EBA
Zinc polycarboxylate (ZPC) = precursors of GICs
Glass ionomers(GIC)
Resin modified glass ionomers(RMGIC)
Compomers(CC)
C. Organics
Resins(RC)
- Classical-used with an adhesive system
- Self-etching(Panavia 2.0, Kuraray)
- Self-adhesive(Clearafil, Kuraray; Maxcem, Kerr)
Classification
3. Delivery form and setting reaction criterion
Powder + liquid
- most of them, acid-base reaction
- RMGIC, acid-base reactionand lightcuring
- some of ZOECs, chelation reaction
- Paste-Paste
- some ofZOECs, chelation reaction
- RCs, light-curing
Classification
4. Type of the liquid component criterion (based on:)
- Orthophosphoric acid (ZOPCs; SPCs; SCs) 2.Phenols(ZOECs, reinforced ZOECs, EBA, HVEBA)
- Polycarboxylic acids(ZPCs, GICs, RMGICs)
- Methacrylic monomers(RCs) 5.Methacrylic monomers withpolycarboxylic groups (=compomer cements=CCs)
Zinc phosphate cements(ZOPCs)
1879
•Bicomponent system: –Powder–zinc oxide+ Mgoxide
–Liquid–orthophosphoric acid+ water+ Al + Zn
•Setting reaction:
–Acid-base, exothermal reaction
–Shrinkage polymerisation
Properties:
-Reduced thermal conductivity= thermal isolators
-Hardness
≻
ZOECs, smaller thanSPCs -Good strength(at compression => higher than to tensile= brittle), increases with the increase of powder -Adhesion–0(=none) -
Opaque materials -High water sorption, especially in the acid environment -Irritantfor the pulpal-dentinal tissue till its setting is completed
Indications
Final luting of prosthetic restorations with metallic substructure
Zinc-oxide-eugenol cements
composition and setting
Composition: –Powder: Znoxide, colophony, benzoicacid, Znstearate
–Liquid: eugenol, olive oil, benzoicacid
•Setting reaction: –Chelation reaction between
eugenol (aromatic) and
Znoxide, with Zneugenolate formation –Water accelerates its setting reaction –Its reaction is reversible –the eugenolate is hydrolyzed in time, into wet environment
Zinc-oxide-eugenolcements
Properties
-Reduced thermal conductivity = thermal isolator -Lower hardness and strength than ZOPCs (they are the weakest ones) -Adhesion–to the hard dental tissues (mechanically)and to metals(they need isolation with paraffin oil) -Opaque cements -Increased solubility, -pH 7-8 –INHIBITS the RBCs’ setting=> use of noneugenolZOEcements -Sedative and bacteriostaticeffects
zoe Delivery form and indications
Delivery form and indications:
–TypeI (temporary luting) •Class1 –powder/liquid •Class2a –paste/ pastewitheugenol •Class2b –paste/ pastewithouteugenol (before use of RCs for final luting) •Class3 -paste/ pastewithout setting –
TypeII (final luting)
•Class1 –powder/liquid–rarelyused
Indications:
Paste/paste ZOEand ZOE-NE cementsused for temporary or permanent luting of the prosthetic restorations with metallic substrate
Other indications
- Base linings under amalgams
- Base linings under glass ionomers
- Temporary fillings
- Paste/paste zinc oxide eugenol root canal sealer
Reinforced zinc-oxide-eugenol cements (modified with polymers)
Packing:
Bicomponent: powder/ liquid
Composition:
Variant 1: hydrogenated resins within powder
Variant2: MMAorpolystyrenewithin liquid
Properties:
BetweenZOECsandZOPCs
The increase of compression strength(40MPa)
More reduced solubility
Indications:
Temporary and permanent cementation
EBAzinc-oxide-eugenol cements (with ortho-ethoxybenzoicacid)
Packing:
Bicomponent: white powder/ pink liquidorpaste/paste
Composition:
Powder: Znoxide(75%), quartz oralumina(20%)and hydrogenated resins (5%)
Liquid: eugenol (37%), EBAacid(63%)
Properties:
The presence ofEBA stimulatesthe crystalline structure formation = higher mechanical strength (60MPa to compression)
The solubility is more reduced
the best properties between ZOECs
BetweenZOPand ZPC
Indications:
Permanent luting
Glass ionomer cements(GIC)
system
setting reaction
properties
Bicomponent system:
–Powder–(see the GIC composition used as restorative materials)
–Liquid–(see the GIC composition used as restorative materials)
•Setting reaction:
–Acid-base, exothermal
–Polymerisation shrinkage
•Properties: –Higher strength than ZOPCsandZPCs –Direct adhesion to the hard dental tissues –increases through the application of the dentin conditioner –More translucent comparing with the others cements –Water sorption in the first 24h higher than the other cements, but minimum in time –Carioprophylactic effect, Frelease –Irritant for the pulp till its setting, stronger than ZOEC,weaker thanZOPC
gic cements indications
Indications
–permanent cementation
•!!! Especially for: –Prosthetic restorations with non-noble metallic substrate
- General indications: –Prosthetic restorations with metallic substrate –Full-ceramic dentures made of oxide ceramic where the resin cements have a weak adhesion
- Relative contraindications(aesthetic considerations): –Full-composite/full-ceramic prosthetic restorations
Cements based on methacrylic monomers–resin cements(RCs)
Evolution:
1.Conventional composite cements used with adhesive
systems(Nexus NX3, Kerr)
2.Self-adhesive composite cements used with acid
primer(Panavia 2.0, Kuraray)
3.Self-adhesive composite cements (same asall-in-one)
(Clearafil, Kuraray; Maxcem, Kerr)
•ADA and ISOclassification:
–Class1 –self-cured
–Class2 –light-cured
–Class3 –dualcured(selfandlight-cured
a.1. Composite ceme
Initiallywere self-cured(paste/ paste)
- Laterdual-cure(paste/ paste) –There are also composite cements used for temporary cementations (Neo-Temp, Provilink) –remove the contamination risk with eugenol, which has negative effects over the permanent cementation with resin cements(RC)
- Composition: –Organic phase–Bis-GMA, UDMA, TEGDMA –Filler–microfillerormicrohybrid
