9. @ Very low viscosity
@ Low dimensional change 0.1%
@ Irreversible chemical change
Disinfection : 2% alkaline
glutarldehyde solution
10. Equal length of the two paste is extruded
shorten by increase
Temperature&Humidity
Working time 3-5 min
Mixing time 45-60 s
Mixed with stainless steel spatula in paper
pad or glass slab
11. Materials are classified as:
HARD PASTE(TYPE 1)
SOFT PASTE(TYPE 2)
FINAL SETTING :
Type 1: within 10 mins
Type 2 : 15 mins
13. Accuracy of soft tissue impression (mucostatic)
Inexpensive
Adhere well to dental compound
Good surface detail reproduction
Good dimensional stability
14. May irritating to soft tissue
Inadequate working or setting time
-excessive humidity and/or temperature
Distortion-unstable tray
15. ZOE cement introduced in 1858, is used as a
Protective , sedative lining in deep carious cavities,
For temporary filling
Temporary cementing
Pulp capping
Root canal filling
Periodontal / surgical packing
Depending on their use they vary widely in their
properties. In general, they are cements of low
strength, are least irritating of all dental cements, are
known to have an obtundant effect on exposed dentin.
16. CLASSIFICATION: (ADA SP. NO. 30) 4 TYPES
TYPE 1 ZOE- for temporary cementation
TYPE II ZOE – permanent cementation
TYPE III ZOE – temporary filling, thermal
insulation
TYPE IV ZOE – cavity liners
AVAILABLE AS :
Powder, liquid
Two paste system
17. Unmodified
Tempac - type III
Cavitic - type IV
Tempbond - type I
EBA alumina modified
Opotow
Alumina EBA - type II
Polymer modifies
Fynal - type II
IRM - type III
Non- eugenol
Nogenol - type I
Freegenol - type I
18. POWDER
Zinc oxide – 69.0% - principal ingredient
White rosin - 29.3% - To reduce brittleness of set cement
Zinc stearate -1.0% - Accelerator , plasticizer
Zinc acetate – 0.7% - Is added in some powders, acts with eugenol in a
similar manner as zinc oxide
LIQUID
Eugenol – 85.0 - Reacts with zinc oxide
Olive oil - 15.0 - Plasticizer
Zinc oxide is also main constituent of gutta-percha points mainly used in
endodontic root canal filling, commonly known as GP Points.
19. First
ZnO + water Zn(OH)2
Second
Zn(OH)2+2HE ZnE2 + H2O
SETTING TIME : 4 - 10 mins
Water accelerates the reaction
Zinc eugenolate is easily hydrolyzed by moistures
20. Complete reaction between zinc oxide and
eugenol takes about 12 hrs. this is too slow for
clinical convenience.
Manufacture: most active ZnO powders are
those formed from zinc salts like zinc
hydroxide, zinc carbonate by heating at 3000
degree Celsius.
Particle size : smaller particles sets faster.
Accelerators : Alcohol, glacial acetic acid, water
Heat : cooling glass slab, slows reaction
Retarders : the set can be treated with glycol ,
glycerin
p/l ratio : higher the ratio, faster the set.
21. MECHANICAL PROPERTIES:
Compressive strength : are relatively weak cements.
Ranges from a low of 3 -4 Mpa upto 50-55 MPa.
Tensile strength : 0.32- 5.3 MPa
Modulus of elasticity : 0.22 – 5.3 GPa
THERMAL PROPERTIES:
Thermal conductivity : 3.98[Cal. Sec-1 cm-2]x
10-4
Co-efficient of thermal expansion : 35x10-
6/celsius
22. Solubility and Disintegration : solubility is highest
among cements (0.4 wt %) . Disintegrate in oral fluids.
Solubility is reduced by increasing p/l ratio.
Film thickness :is 25 um, is higher than other
cements.
Adhesion : do not adhere well to enamel or dentin
Biological properties :
PH and effect on pulp: PH is 7 -8 ; pulpal response
classified as mild
Bacteriostatic and obtundant properties
Optical properties : set cement is opaque
24. P/L SYSTEM: p/l ratio : 4:1- 6:1 by wt
Oil of orange is used to clean eugenol cement
from instruments.
TWO PASTE SYSTEM: equal lts. Of each paste
are dispersed and mixed until a uniform color
is observed.
SETTING TIME :4-10 MINS
ZOE cements set quickly in mouth due to
moisture and heat.
28. Glass slab are recommended for EBA- alumina
modified cements. after dispensing , powder is inco.
Into liquid in bulk, kneaded for 30 secs, and then
stropped for an additional 60 secs with broad strokes
of spatula to obtain a creamy consistency. They have
long working times.
SETTING TIME:
9.5 MINS
29. Composition:
POWDER : Zinc oxide- 70 %
finely divided natural or synthetic resins
LIQUID : Eugenol
acetic acid – accelerator
Thymol - antimicrobial
zinc oxide is surface treated
SETTING REACTION: Similar to zoe cements. acidic
resins, if present, may react with zinc oxide,
strengthening the matrix.
SETTING TIME : 6-10 MINS
FACTORS AFFECTING SETTING TIME:
Low p/l ratio inc. setting time
Moisture: accelerates setting time.
30. Cements have improved mechanical properties.
Compressive st :48 MPa
Tensile st : 4.1 Mpa
Modulus of elasticity : 2.5 GPa
Film thickness : 32 um
solubility ,disintegration : 0.03 % wt
pulp response : similar to unmodified zoe -
moderate
improved abrasion resistance and toughness.
MANIPULATION :
PROPER P/L is dispensed on a dry glass slab. Powder
is mixed into liquid in small portions with vigorous
spatulation.
WORKING TIME : Long working time.
31. Luting agent
As base
As temporary filling material,
As cavity liner
32. Some zoe materials contain antibiotics such as tetracycline,
steroids as anti- inflammatory agents. Their principal use is in
pulp capping and RCT. One product also contains barium
sulphate, which is radiopaque.
ZINC OXIDE/ ZINC SULPHATE TEMPORARY
RESTORATIONS:
These are single component temporary filling materials.
Supplied as a single component putty like paste in small tubes,
syringes or plastic containers.
Commercial Names : Cavit (ESPE) , Caviton (GC) , Coltosol
(Coltene)
Use in short term temporary restorations after caries excavation,
RCT etc.
33. COMPOSITION: zinc oxide; zinc sulphate -1- hydrate ; calcium
sulphate – hemihydrates ; dibutyl phthalate (plasticizer) ;
diatomaceous earth.
SETTING REACTION: sets by chemical reaction, it sets by
reacting with water which it absorbs from the mouth or from the
cavity. Setting occurs slowly, expands on setting.
SETTING TIME : Surface hardens in about 20 to 30 mins.
Complete hardening takes place in 2-3 hrs.
PROPERTIES : May be white /pink colored. Has good initial
sealing. as expands on setting, marginal seal is further improved.
Seal gradually dec. with time. strenght is low, its life is short,so
material must be used for not more than 1-2 wks.
MANIPULATION : material is dispensed, inserted into cavity
using a cement carrier . container should be closed immediately,
material is condensed into cavity using a plastic filling instrument
; as sets by hydration , cavity should not be fully dried before
placing the material.
34. It is probably the most commonly used root canal
filling material for primary teeth.
Camp in 1984 introduced endodontic pressure syringe
to over come the problem of underfilling .
Underfilling is frequently clinically acceptable.
Overfilling may cause a mild foreign body reaction.
Another disadvantage of ZOE paste is difference
between its rate of resorption and that of the root tooth.
36. Properties ZOE Ca(OH)2 with
Iodoform
(VITAPEX)
KRI Paste
1. Restore at the same rate
as the tooth
2. Harmless
3. Overfill resorbs
4. Antiseptic
5. Easily applied
6. Adheres to the wall
7. Easily removed
8. Radiopaque
9. No discoloration
Y
Y
Y
Y
Y
Y
Y
Y
Y
Y
Y
Y
Y
Y
Y
Y
Y
Y
Y
Y
Y
Comparison of materials used for
pulpectomy in primary teeth
37. The material has been involved in a wide range
of applications in dentistry, including use as an
impression material for edentulous mouths, a
surgical dressing, bite registration paste,
temporary filling material, root canal filling
material, cementing medium, temporary
relining material for dentures . The physical
and mechanical properties and handling
characteristics generally are inferior to those of
other long –term luting cements. Main
advantage of improved ZOE cements is their
biocompatibility.