The document discusses different types of cements used for cementation including: zinc phosphate cement, polycarboxylate cement, zinc oxide eugenol, glass ionomer cement, resin luting cement, and hybrid ionomer cements. It provides details on the composition, properties, strengths, and limitations of each type of cement. The steps in the cementation process are also outlined which involve coating the crown with cement, placing it on the tooth, removing excess cement, and checking contacts.

1. CEMENTATION
Saif Jawad
1330154

2.  The mechanisms that hold a
restoration on a prepared tooth
can be divided into:
nonadhesive (mechanical)nonadhesive (mechanical)
lutingluting, micromechanicalmicromechanical
bondingbonding, and molecularmolecular
adhesionadhesion.

3. Bonding Mechanisms
 Nonadhesive lutingNonadhesive luting
– served primarily to fill the
gap and prevent entrance of
fluids

4.  MicromechanicalMicromechanical
bondingbonding
– necessary deep irregularities can be
produced on enamel surfaces by etchingon enamel surfaces by etching
with phosphoric acid solution or gelwith phosphoric acid solution or gel; onon
ceramics, by etching with hydrofluoricceramics, by etching with hydrofluoric
acidacid; and on metal, by electrolytic /on metal, by electrolytic /
chemical etching, and sandblastingchemical etching, and sandblasting

5.  Molecular adhesionMolecular adhesion
– involves physical forces
and chemical bonds
between molecules of two
different substances

6. TYPES OF CEMENTS

7. 1. Zinc Phosphate Cement
 possesses high
compressive
strength
 exhibits a pH of
3.5 at the time of
cementation which
contributes to
pulpal irritation
 needs cavity
varnish to reduce
exposure of pulp
to the cement

8. 2. Polycarboxylate Cement
 higher tensiletensile
strengthstrength (resistance
to lengthwise stress)
 pH is also low (4.8)
 cause little pulpal
irritation
 shows moderately
high bond strength to
enamel and dentin
 bonds to stainless
steel, but not to gold

9. 3. Zinc Oxide Eugenol
 cause no pulpal
inflammation as
long as they make
no direct contact
with the pulp
 used as temporary
cements
 soluble than zinc
phosphate
 deteriorates more
rapidly in the mouth
than other cements

10. 4. Glass Ionomer Cement
 composed mainly of
calcium fluoro-
aluminosilicate glass
 compressive
strength and tensile
strength are quite
good
 bacteriostatic
 releases fluoride at a
greater rate than
silicate cement
 pH is lower than zinc
phosphate which
cause post
cementation
hypersensitivity
-varnish is not recommended-varnish is not recommended
-weakened by early-weakened by early
exposure to moistureexposure to moisture

11. 5. Resin Luting Cement
 composed of resin
matrix and a filler of
fine inorganic particles
 low filler content and
low viscosity
 virtually insoluble and
much stronger than
conventional cements
 high tensile strength
makes them useful for
micromechanically
bonding etched
ceramic veneers
 dentin bonding agent is
necessary prior to
resin cement
-problems encountered-problems encountered
include excessive cementinclude excessive cement
film thickness, marginalfilm thickness, marginal
leakage because of settingleakage because of setting
shrinkage, and severe pulpalshrinkage, and severe pulpal
reactions when applied toreactions when applied to
vital dentinvital dentin

12. 6. Hybrid Ionomer Cements
 glass filler
particles react
with the liquid
during the
hardening
process
 combined the
strength and
insolubility of
resin with the
fluoride release
of glass ionomer

13. STEPS IN
CEMENTATION

14. Mix the cement in circular motion

15. Consistency of the cement should not be
too flowy or too sticky

16. The inner walls of the crown are coated with a thin layer of
cement using the small end of an instrument (A)
or a brush (B).
A B

17. Insert the crown on the abutment

18. Remove excess cement

19. Proximal contacts are tested with dental floss to
remove excess cement and ensure proper
interproximal spaces in between teeth