Glass ionomer cement
Glass Ionomer Cement[edit]
Glass ionomer cement (GIC) is a dental restorative material used in dentistry for filling teeth and luting cements. It is made from a combination of silicate glass powder and polyacrylic acid. Glass ionomer cements are known for their ability to release fluoride, which can help in remineralizing tooth structure and preventing caries.
Composition[edit]
Glass ionomer cements are composed of a calcium or strontium alumino-fluoro-silicate glass powder and an aqueous solution of polyacrylic acid. The setting reaction involves an acid-base reaction between the glass powder and the polyacrylic acid, resulting in a hard, water-insoluble material.
Properties[edit]
Glass ionomer cements have several advantageous properties:
- Fluoride Release: They release fluoride ions over time, which can help in the prevention of dental caries.
- Biocompatibility: GICs are generally well-tolerated by the surrounding tissues.
- Adhesion: They chemically bond to both enamel and dentin, providing a good seal and reducing microleakage.
- Thermal Expansion: Their coefficient of thermal expansion is similar to that of natural tooth structure, reducing the risk of cracking.
Applications[edit]
Glass ionomer cements are used in various dental applications, including:
- Restorative Dentistry: For filling cavities, especially in non-load bearing areas.
- Luting Cements: For cementing crowns, bridges, and orthodontic appliances.
- Base or Liner: Under composite restorations to protect the pulp.
- Fissure Sealants: To prevent caries in pits and fissures of teeth.
Advantages and Disadvantages[edit]
Advantages[edit]
- Fluoride Release: Provides an anti-cariogenic effect.
- Chemical Bonding: Bonds to tooth structure without the need for a separate bonding agent.
- Biocompatibility: Generally well-tolerated by the pulp and surrounding tissues.
Disadvantages[edit]
- Aesthetic Limitations: Less aesthetic compared to composite resins.
- Mechanical Properties: Lower strength and wear resistance compared to other restorative materials.
- Moisture Sensitivity: Sensitive to moisture during the initial setting phase.
