Glass Ionomer in Contemporary
Restorative Dentistry
By Rooj Rojasawasthien. DDS, MSc.
16 August 2010
Direct Tooth Colored Material
• Resin composite• Compomer (Polyacid
Modified Resin)• Glass Ionomer• Resin Modified Glass
Ionomer
Direct Tooth Colored Material
GICGlass Ionomer
Cements
RMGIResin-ModifiedGlass Ionomers
PAMRPolyacid-ModifiedResin (compomer)
IMCRIonomer-Modified
Composite Resins
(fluoride in resin)
CRComposite Resins(glass-containing
Hydrophobic resins)
Glass Ionomer• Silicate cements ---> Glass
ionomer (Wilson and Kent, 1972)
• Powder + Liquid• Fluoroaluminosilicate glass
+ Polyalkenoic acid• Acid – Base reaction
Mixing - Shiny, Glossy
Phase I (Ion-leaching phase)Polyacid extracts ions from glass
powder
Setting (3-6 min) - Rigid, Opaque
Phase II (Hydrogel phase)Ion cause formation of polyacid
matrix
Maturation (24 hrs – 1 yrs) More tooth-like color
Phase III (Polysalt gel phase)Silica gel forms and attaches
powder to matrix
Fully set Glass Ionomer
Advantages• Less shrinkage than
polymerizing resin• No free monomers, Non-
irritating to pulp• Coefficient of thermal expansion similar to dentin
• High compressive strength
Advantages
• Adhere chemically to enamel and dentin (hydrophilic)
Advantage• Fluoride release and
recharge (reservoir effect)
Delbem et al., 2005
Disadvantages• Poor abrasion resistance• Average esthetic• Technique sensitive• Susceptible to take up
additional waterHygroscopic
expansion• Susceptible to dehydration
Crazing, Cracking
Disadvantages
Wear rate Tensile strength
Conventional GI(capsule)
Metal-reinforced GI
Conventional GI(hand mix)
Development of Glass Ionomer
High viscous glass ionomer
Classification• Self-cure glass ionomer–Conventional glass ionomer • Fuji II lining (GC Co., Japan)• Ketac Fil Plus (3M ESPE, USA)
• Ketac Cem
Classification• Self-cure glass ionomer–Metal-reinforced glass ionomer• Miracle Mix (GC Co., Japan), Ketac silver (ESPE)
Classification• Self-cure glass ionomer–High viscous glass ionomer
Fuji IX (GC Co., Japan), Ketac Molar (3M ESPE, USA)
Development of Glass Ionomer
Conventional GI
Resin Components
4.5 – 6 %
Resin-Modified
GI
Resin-modified glass ionomer• Hydroxyethyl
methacrylate (HEMA)• Vitrebond, first commercial in 1989
• Acid-Base reaction + Photo-chemical polymerization–Dual-cure–Tri-cure : add autocure resin
Resin-modified glass ionomer (RMGI)Conventional GI RMGI
Vitrebond, Vitremer
Acid-base and light-polymerization reaction compete with and inhibit one
another (Berzin. et al, 2010)
Resin-modified glass ionomer (RMGI)• Improve properties
–Set on demand–Fewer desiccation and hydration problems
–Immediate finishing–Better esthetics–Tensile strength, fracture toughness
–Resistance to microleakage
–Bond to resin composite
Fuji Plus
RMGI products• Luting agent
FujiCem
Rely-X luting cement
RMGI products• Liner / Base
Fuji lining LC Vitrebond
RMGI products• Composite bonding agent–Fuji Bond LC
RMGI products• Restorative buildup
Fuji II LC
Vitremer Ketac Nano
RMGI - Restorative
GC Fuji II LC
Dentin conditioner
3M Vitremer, Ketac Nano
Primer
10% Polyacrylic acid
- 46% HEMA- 39% Ethyl alcohol- 15% Polyacrylic acid- Photoinitiator
RMGI - Restorative
Rinse
Do notRinse
RMGI - Restorative10% Polyacrylic acid37% Phosphoric acid
800x 12,000x
An atlas of glass ionomer cements, 2002
RMGI - Restorative• For Fuji II LC, 10% polyacrylic acid application is able to create micro-mechanical retention.
(Sidhu, 1999)
• For Vitremer, due to high amounts of HEMA, hydrolitic degradation of Vitremer-dentin bonds might be expected to occur. (Fritz et al., 1996)
• In term of bond durability, sealing ability, Fuji II
LC is better than Vitremer. (Fagundes et al., 2009)
Clinical using of RMGI – Class V
Clinical using of RMGI – Class V
Clinical using of RMGI – Class V
Onal & Pamir, 2005
Two years laterVitremer
Compomer
Composite
Clinical using of RMGI – Class V
Puemans et al., 2005
3-step etch and rinse
2-step etch and rinse
Glass ionomer
Survival rate
Clinical using of RMGI – Class V
Puemans et al., 2005
Failure rate
Clinical using of RMGI – Root caries
Clinical using of RMGI – Sandwich tech.
The sandwich technique with resin-modified glassionomer cements or compomers can
improve the marginal adaptation of Class II composite restorations with cervical margins located in dentine (Dietrich. et al, 1999)
Clinical using of RMGI – Sandwich tech.
Liebenberg , 2005
Clinical using of RMGI – Sandwich tech.
Liebenberg , 2005
Clinical using of RMGI – Sandwich tech.
Clinical using of RMGI• Secondary caries
F- release
Remineralization
Reduce secondary caries
Clinical using of RMGI• Secondary caries
Sidhu , 2010
Under fluoride dentifrice, the RMGI provided additional protection
against secondary caries. (Sousa et al., 2009)
Conclusion
Conclusion• Advantages
–Adhere chemically to tooth structure
–Fluoride release–Less shrinkage
• Disadvantages–Lower wear resistance and physical properties compare to composite
–Moisture sensitivity remain–Unstable color
Thank You
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