Ceramic EMAX Onlays: Conservative, Aesthetic Tooth Restoration

EMAX (lithium disilicate) onlays are a minimally invasive, high-strength ceramic restoration for posterior teeth with moderate structural loss.

Indications

• Large failing restorations (amalgam, composite).
• Cuspal fracture or crack risk.
• Endodontically treated teeth (with adequate ferrule).
• Worn dentition requiring vertical dimension restoration.

Advantages Over Crowns

• Preserves 30–50% more tooth structure.
• Supra-gingival margins possible → better periodontal health.
• Excellent aesthetics: translucency mimics enamel; shade matching precise.
• High flexural strength (360–400 MPa); fracture resistance.
• Biocompatible; low plaque affinity.

Clinical Workflow

1. Diagnosis & Planning: Radiographs, bite analysis, mock-up if aesthetic zone.
2. Preparation: Conservative, supragingival where possible; 1.5–2 mm occlusal reduction, 1 mm axial walls. No bevels.
3. Impression/Scan: Digital (IOS) or conventional (PVS). Bite registration.
4. Provisional: Composite or bis-acryl temporary; spot-etch if needed.
5. Fabrication: CAD/CAM milling (chairside or lab) or press technique. Stain/glaze.
6. Delivery: Try-in, etch (HF acid), silane, adhesive, dual-cure resin cement. Light cure. Occlusal adjustment, polish.

Longevity and Maintenance

• 10–15+ year survival with proper case selection and bonding protocol.
• Regular hygiene and occlusion checks.
• Night guard if bruxism present.

EMAX onlays represent the current gold standard for conservative posterior ceramic restoration.