Direct Esthetic Restorative Materials Pt. 2 - GIC and RMGIC
1. Glass ionomer cement
2. Resin-modified glass ionomer cement
1. Glass Ionomer Cement:
➢ Used in cervical and class 5 restorations in
adults where esthetics is not critical
➢ Recommended for patients with a high risk of
carries
○ The filler has a different composition
○ It releases fluoride.
➢ Types of Glass ionomer:
Type 1: Luting (gluing) Type 2: Restorative Type 3
- Low viscosity - Higher viscosity - Used as liners and bases
- Finer glass particles - Larger particles (50um) - base cement in big
(about 15um) - P.L ratio: 3.1:1 , up to cavities
- To attach crown 3.6:1
- P/L ration 1.7:1 - Setting time: 7 minutes
(1.7 grams of powder for
1 milliliter of liquid)
- Setting
time:
4-5
mins
Indication of GIC Type II:
➢ Situations of high caries activity
○ Elderly
--
○ xerostomia - when there’s not enough saliva to keep the mouth wet
➢ Small non-stress bearing restorations
➢ Cervical cavities: (when the cavities are near to the gums in a way)
○ Abfraction: type of tooth wear that causes progressive loss of tooth
structure
➢ Core buildups
➢ Intermediate restorations
➢ Primary tooth fillings
, Conventional Glass Ionomer (1970):
➢ Composition:
○ Powder: SiO2 , CaF2, Al2O3, AlF3, AlPO4, Na3AlF6
■ Ion leachable calcium fluoro aluminosilicate glass
○ Liquid: polyacrylic acid, itaconic acid/maleic acid, tartaric acid,
water
■ Polyacrylic Acids:
● Polymeric carboxylic acids
● COOH group
● Weak acid
Acrylic: highly reactive carboxylic acid
that can react with itself to form
polyacrylic acid.
Maleic Acid: dicarboxylic acid
Itaconic Acid: classified as a
dicarboxylic acid
Tricarboxylic acid
( Tartaric Acid:
Accelerates Improves handling
Extends working time
Decreases setting time - sets faster
Extends shelf life.
Polycolic
Setting Reaction: Acid-Base Reaction:
~
-
➢ When the powder and liquid are mixed for a GIC, the acid starts to
- dissolve the glass > so glass releases in
-
➢ Releases:
○ Calcium ions
○ Aluminum ions
-○ Fluorine ions
➢ The polyacrylic acid chains are cross-linked by the calcium ions,
-
and form calcium polysalts
○ Polysalts are responsible for the initial set (calcium is
released more rapidly)
➢ Aluminum ions are released more slowly, they become involved in
setting at a later stage by forming aluminum polysalts.
1. Glass ionomer cement
2. Resin-modified glass ionomer cement
1. Glass Ionomer Cement:
➢ Used in cervical and class 5 restorations in
adults where esthetics is not critical
➢ Recommended for patients with a high risk of
carries
○ The filler has a different composition
○ It releases fluoride.
➢ Types of Glass ionomer:
Type 1: Luting (gluing) Type 2: Restorative Type 3
- Low viscosity - Higher viscosity - Used as liners and bases
- Finer glass particles - Larger particles (50um) - base cement in big
(about 15um) - P.L ratio: 3.1:1 , up to cavities
- To attach crown 3.6:1
- P/L ration 1.7:1 - Setting time: 7 minutes
(1.7 grams of powder for
1 milliliter of liquid)
- Setting
time:
4-5
mins
Indication of GIC Type II:
➢ Situations of high caries activity
○ Elderly
--
○ xerostomia - when there’s not enough saliva to keep the mouth wet
➢ Small non-stress bearing restorations
➢ Cervical cavities: (when the cavities are near to the gums in a way)
○ Abfraction: type of tooth wear that causes progressive loss of tooth
structure
➢ Core buildups
➢ Intermediate restorations
➢ Primary tooth fillings
, Conventional Glass Ionomer (1970):
➢ Composition:
○ Powder: SiO2 , CaF2, Al2O3, AlF3, AlPO4, Na3AlF6
■ Ion leachable calcium fluoro aluminosilicate glass
○ Liquid: polyacrylic acid, itaconic acid/maleic acid, tartaric acid,
water
■ Polyacrylic Acids:
● Polymeric carboxylic acids
● COOH group
● Weak acid
Acrylic: highly reactive carboxylic acid
that can react with itself to form
polyacrylic acid.
Maleic Acid: dicarboxylic acid
Itaconic Acid: classified as a
dicarboxylic acid
Tricarboxylic acid
( Tartaric Acid:
Accelerates Improves handling
Extends working time
Decreases setting time - sets faster
Extends shelf life.
Polycolic
Setting Reaction: Acid-Base Reaction:
~
-
➢ When the powder and liquid are mixed for a GIC, the acid starts to
- dissolve the glass > so glass releases in
-
➢ Releases:
○ Calcium ions
○ Aluminum ions
-○ Fluorine ions
➢ The polyacrylic acid chains are cross-linked by the calcium ions,
-
and form calcium polysalts
○ Polysalts are responsible for the initial set (calcium is
released more rapidly)
➢ Aluminum ions are released more slowly, they become involved in
setting at a later stage by forming aluminum polysalts.
