classification best explained, types and purposed

1. GLASS IONOMER CEMENT
BY: NIKHILA N KASHYAP

2. CONTENTS
 Introduction
 History
 Composition
 Classification
 Dispensing
 Manipulation
 Setting reaction
 Properties
 Indications and contraindications
 Advantages and disadvantages

3. INTRODUCTION
 What is a cement?
 A cement is a substance that hardens to act
as a base ,liner ,filling material ,or adhesives
to bind devices or prosthesis to the tooth
structure or to each other.

4. GLASS IONOMER CEMENT
It is a tooth colored
material
Based on reaction
between silicate glass
powder and polyacrylic
acid
Chemically bind to
tooth structure
ADA specification
number 96

5. HISTORY
 Invented in 1969
 Reported by wilson and kent in 1972
 The term was coined by B.E KENT
 Other names:
Ionomer poly-carboxylate acid
ISO terminology Poly-alkenoate cement
Since its extensive usage to replace the
dentin-dentin substitute , man-made dentin,
artificial dentin
ASPA- alumino silicate poly-acrylate.

6. COMPOSITION
Species Composition(%)
Silica (SiO2) 30.1
Alumina (Al2O3) 19.9
Aluminium fluoride
(AlF3)
2.6
Calcium fluoride (CaF2) 34.5
Sodium fluoride (NaF) 3.7
Aluminium phosphate
(AlPO4)
10.0
Powder: It is an acid soluble calcium
fluoro aluminosilicate glass

7. LIQUID
Species composition(%)
Polyacrylic acid 40-50%
water 50%
Itaconic acid , maleic
acid , tri carboxylic acid
0.5%
Tartaric acid 5-15%

8. CLASSIFICATION
According to A.D Wilson
I. Type 1: Luting agents
II. Type 2: Restorative cements
a)aesthetic filling material
b)bis-reinforced filling material
III Type 3: Lining, base and fissure sealing
materials

9. According to application
 Type 1) luting
 Type 2) restoration
 Type 3) liners and base
 Type 4) pit and fissures sealants
 Type 5) luting for orthodontic purpose
 Type 6) core build up material
 Type 7) fluoride releasing GIC
 Type 8) for ART
 Type 9) for pediatric purpose

10. DISPENSING
Commercially
available in 2 forms
1. Encapsulated
2. Powder and
liquid

11. MANIPULATION
1) Tooth preparation:
 Pumice slurry is used to remove the smear
layer.
 Etched with phosphoric acid and rinse
 tooth surface should be cleaned and dried
for sustained adhesion .

12. 2) MATERIAL PREPARATION
 P/L ratio – 3:1
by weight
paper pad or
dry glass slab is
used
WHY?
Powder and
liquid is
dispensed just
before mixing

13.  Powder is
incorporated rapidly
into the liquid
 Half of the powder is
mixed into liquid for
5-15 seconds , rest
is then quickly
added and mixed to
get a uniform glossy
appearance .

14. CLINICALSTEPS
In cervical abrasion cases

15. Pumice prophylaxis

16. Dentin conditioning

17. APPLICATION OF GIC

18. FINISHING
Excess material
must be trimmed
from margins
Hand
instruments
preferred to
rotary
instruments to
avoid ditching
Further finishing
is done after 24
hours

19. SETTING TIME
TYPE 1 4-5 Minutes
TYPE 2 7 Minutes

20. SETTING REACTION
 Stage 1) Dissolution
 Stage 2)precipitation of salts, gelation and
hardening.
 Stage 3) hydration of salts

21. STAGE 1)
DISSOLUTION
Surface layers of
glass particles are
attacked by poly
acids and ions are
released
Produce diffusion
based adhesion
between glass
particles and matrix

22. STAGE 2) PRECIPITATION, GELATION AND
HARDENING
Calcium and aluminium ions bind to poly
ions
Initial clinical set-Cross linking of ca ions -4-
10 minutes from setting
Next 24 hours –less mobile aluminium ions
bound within the cement matrix – more rigid
cross linking
Fluoride and phosphate ions forms
insoluble salts and complexes
Sodium ions – binds the powder to matrix

23. STAGE 3) HYDRATION OF SALTS
 progressive hydration of matrix salts
 Sharp improvement in physical properties

24. SETTING RATE
 Manufacturer controlled
glass composition
glass fusion temperature,
powder particle size,
tartaric acid concentration
 Operator controlled
Mixing temperature-storage of slab and
powder in a refrigerator increases the working time
up to 25%
Powder: liquid ratio-inadequate liquid
results in a decline in translucency and physical
properties

25. PROPERTIES
 Adhesion: chemically binds to tooth structure
 Bio compatibility: resistance to plaque ,
plaque fails to thrive on the surface of GIC
 Pulpal response to GIC: formation of dentin
bridge occur when used to protect a
mechanical or traumatic exposure of pulp
 Remineralising effect

26.  Solubility : initial solubility is high due to
leaching of intermediate products
is low when compared to zinc
phosphate and zinc polycarboxylate
 Dimensional change : volumetric setting
contraction of approximately 3%
 Strength : susceptibility to brittle fracture .
Weak and lack rigidity when compared to
composites and amalgams
 Abrasion resistance : immediately after
placement-less resistance to abrasion , as
they mature their resistance improves

27.  Thermal diffusivity
 Color and translucency: type II a) restorative
esthetic material provide adequate color
matching and translucency
 Radiopacity:more radiopaque than dentin and
several exceed that of enamel
 Anticariogenic property: fluoride is released at
the time of mixing and lies within the matrix
- flouride reserviour

28. MODIFICATIONF OF GIC
1) Water settable GIC
Liquid used is clean water
Liquid is delivered in a freeze dried form ,which is
incorporated into the powder
2) Resin modified GIC
Powder component consist of ion leachable
fluroalumino silicate glass particles and initiator for
light curing
Liquid component consist of water and poly acrylic acid
with methacrylate and hydroxyl ethyl methacrylate
monomer

29. 3) Metal modified GIC
GIC have been modified by addition of filler
particles, to improve strength fracture toughness
and resistance to wear
Silver alloy admix / miracle mix
This is made by mixing of spherical silver
amalgam alloy powder with glass ionomer
powder
Cerment
Bonding of silver particles to glass ionomer
particles by fusion through high temperature
sintering

30. 3) Compomer
It is a composite resin that uses and ionomer
glass which is the major component of glass
ionomer as the filler
Small quantity of dehydrated poly alkenoic acid
incorporated with filler particles
Setting reaction is light activated
Adhesive system used with compomer is
based on acid etch found with all composite
resin

31. ATRAUMATIC RESTORATIVE TREATMENT
PRINCIPLES
1.Removing carious tooth tissue using hand
instruments only
2.Restoring the cavity with adhesive
material(glass ionomer)
Why GIC?
Chemically binds to enamel and dentin
Flouride release to prevent and arrest caries
Biocompatible – no irritation to pulp and gingiva

32. INDICATIONS
 Type I) useful in patients with high caries index
 Type II) restoring of erosion / abrasion lesions without
cavity preparation
sealing and filling occlusal pits and fissures
restorations of class III lesions
repair of defective margin in restoration
core build up
intermediate restoration
 Type III) lining of all types of cavities where a biological
seal and cariostatic action are required
sealing and filling of occlusal fissures showing
early signs of caries

33. CONTRAINDICATIONS
 Class IV carious lesions or fractured incisors
 Class II carious lesions where conventional
cavities are prepared
 Replacement of existing amalgam restoration
 Lost cusp areas

34. ADVANTAGES
 Inherent adhesion to tooth structure
 Good marginal seal
 Anticariogenic property
 Biocompatibility
 Minimal cavity preparation required
 Restoration in primary dentition

35. DISADANTAGES
 Low fracture resistance
 Low wear resistance
 Water sensitive during setting phase
 Less esthetics compared to composites