glass ionomer cement
INTRODUCTION Glass ionomer cement is a tooth coloured material, introduced by Wilson & Kent in 1972.Material was based on reaction between silicate glass powder & polyacrylic acid.They bond chemically to tooth structure & release fluoride for relatively long period.
CLASSIFICATION
- Type I: For luting
- Type II: For restoration
- Type III: For liner & bases
- Type IV: Fissure & sealent
- Type V: As Orthodontic cement
- Type VI: For core build up
- Type VII: Restorative esthetic
- Type VIII: Restorative reinforced
- Type IX: Pediatric and geriatric
Indications:
- Restoring of erosion/ abrasion lesions without cavity preparation.
- Sealing and filling of occlusal pits and fissures
- Restoration of deciduous teeth.
- Restoration of class III lesions, preferably using a lingual approach with labial plate intact.
- Repair of defective margins in restorations
- Minimal cavity preparations – Approximal lesions, Buccal and Occlusal approach (tunnel preparation)
- Core build-up
Advantages:
- Polymerisation shrinkage is less,due to reduced bulk of composite.
- Favorable pulpal response.
- Chemical bond to the tooth.
- Anticariogenic property.
- Better strength,finishing,esthetics of overlying composite resin.
- Microleakage is reduced
- Minimization of no. of composite increments, therefore time is saved
Disadvantages :
- Brittle
- Soluble
- Abrasive
- Water sensitive during setting phase.
- Some products release less fluoride than conventional GIC
- Not inherently radiopaque though addition of radiodense additives such as barium can alter radiodensity
- Less aesthetic than composite