What are the uses of glass ionomer (GI) cement in dental restorations?

Glass Ionomer Cement Uses in Dental Restorations

Glass ionomer cement is a versatile dental material indicated for interim therapeutic restorations in cavitated lesions (especially in young/uncooperative children), luting cement for indirect restorations, liner/base materials, and dental sealants, with traditional GIC preferred when moisture control is compromised and resin-modified GIC reserved for situations with optimal isolation. 1, 2

Primary Clinical Applications

Restorative Uses

• Interim therapeutic restorations for managing cavitated lesions in young children, uncooperative patients, children with special healthcare needs, and circumstances where traditional restorations are not feasible 1
• Load-bearing restorations where adequate remaining tooth structure supports the material and heavy occlusal loading is absent 3, 4
• Permanent restorations in non-stress-bearing areas, supported by evidence showing comparable clinical performance to traditional materials for surface margins, retention, marginal adaptation, and wear 3

Luting and Bonding Applications

• Luting cement for indirect restorations, including crowns and fixed prostheses 5
• Adhesive bonding to tooth structure without requiring separate bonding agents due to chemical adhesion properties 4, 6
• Sandwich technique as a base material under composite restorations 6

Preventive Applications

• Dental sealants for pit and fissure protection, though application may be challenging in infants and toddlers 1, 5
• Liner and base materials under other restorations, though this indication remains somewhat debatable 5

Material Selection Algorithm

When to Use Traditional GIC (Conventional Glass Ionomer)

• Moisture control is compromised or impossible - traditional GIC tolerates moisture during setting, making it the only appropriate choice when absolute dryness cannot be achieved 2, 7
• Young, uncooperative children requiring minimally invasive techniques 1
• Field settings where dental therapists and hygienists provide care without optimal moisture control 2
• Situations prioritizing fluoride release and chemical adhesion over maximum strength 4, 5

When to Use Resin-Modified GIC (RMGIC)

• Only when absolute moisture control is achievable - RMGIC is highly moisture-sensitive and requires completely dry surfaces for proper adhesion 2, 7
• Never proceed with RMGIC if complete dryness cannot be achieved, as moisture contamination causes restoration failure 7
• Situations requiring improved physical properties compared to traditional GIC, but only with optimal isolation 5

Key Material Properties Driving Clinical Use

Advantages

• Direct chemical adhesion to tooth structure without separate bonding agents 4, 5, 6
• Long-lasting fluoride release for caries prevention 4, 5, 6
• Minimal shrinkage or expansion during setting 5
• Coefficient of thermal expansion similar to natural tooth structure 5
• Biocompatibility with dental tissues 5
• Tooth-colored aesthetic appearance 4

Limitations

• Sensitivity to moisture (especially RMGIC) requiring careful technique 4, 2
• Inherent opacity limiting aesthetic applications 4
• Lower long-term wear resistance compared to resin composites 4
• Reduced strength compared to other restorative materials, necessitating adequate tooth structure support 4

Critical Clinical Pitfalls to Avoid

• Never use RMGIC without adequate moisture control - this is a primary cause of restoration failure 7
• Do not proceed with adhesive cementation if complete dryness cannot be achieved when using moisture-sensitive materials 7
• Avoid using GIC in high-stress areas without adequate remaining tooth structure to support the material 4
• Do not apply excessive material that could pool in margins; use the least amount necessary 8

Special Populations and Settings

• Midlevel dental professionals (dental therapists and hygienists) can provide interim therapeutic restorations with GIC in many locales 1
• Children with special healthcare requirements benefit from the minimally invasive nature of GIC restorations 1
• High caries-risk populations benefit from the fluoride-release properties 5, 6

Evidence Quality Considerations

The American Academy of Pediatric Dentistry and American Dental Association provide the strongest guideline support for GIC use in pediatric interim therapeutic restorations 1, 2. Recent systematic reviews from 2024 demonstrate that GIC performs comparably to traditional materials for multiple clinical parameters including retention, marginal adaptation, and wear, while reducing postoperative sensitivity and caries recurrence 3. The WHO's addition of GIC to the Model List of Essential Medicines in 2021 underscores its efficacy, safety, and cost-effectiveness 5.