Lithium Disilicate Bonding Protocol
Lithium Disilicate crowns can be conventionally cemented if enough retention and thickness of ceramic material is present. The decision whether the crown should be bonded or cemented must be done ahead of time, so the proper protocol can be followed.
Click here for a PDF printable copy of this protocol, courtesy of the University of Colorado School of Dental Medicine Clinics.
Try-in procedures: Apply a “mist” of water to internal surface of crown prior to applying “Fit Checker®”. Check for margin adaptation, proximal and occlusal contacts.
Determine if adjustments are necessary. The adjustments should be made on tooth structure and NOT on the intaglio. Use fine diamond and don’t alter margins of preparation.
Pumice to clean preparation.
To adjust porcelain surface for proximal and occlusal contacts, use Dialite porcelain polishing, and polish to a high smoothness using the proper sequence of polishing points.
Clean the intaglio with Ivoclean and blast with glass beads if available.
Use Fuji Plus or Ketac GIC to cement.
Crowns received from the lab have the intaglio already etched with hydrofluoric acid (HF). Ideally, this step must NOT be repeated.
Apply 1 coat of silane (Premier), allow evaporation or air dry.
Try-in procedures: Mist the intaglio surface of the crown with water. Apply “Fit Checker” and seat on the tooth. Check for margin adaptation, proximal and occlusal contacts. Try-in paste can be used at this time to check color. (Note: the mist will aid in removal of the Fit Checker and minimize contamination of the etch/silane surface)
If minor adjustments are needed to fit the ceramic crown:
Adjustments should be made on tooth structure and NOT on the intaglio. Use fine diamond and don’t alter margins of preparation.
- To adjust porcelain surface for proximal and occlusal contacts, use Dialite porcelain polishing, and polish to a high smoothness using the proper sequence of polishing points.
Clean the intaglio with Ivoclean or apply 37% Phosphoric Acid for 1min, rinse with water and dry.
- Procedures on tooth structure:
- Clean tooth preparation with non-fluoride containing pumice paste;
- Establish proper isolation (Isovac, retraction cord with Hemodent)
- Protect adjacent teeth from acid etching (i.e. Teflon tape)
- Apply 37% Phosphoric Acid for 30s on enamel and 15 s on dentin;
- Apply OptiBond Solo Plus, air thin and DO NOT light cure.
Procedures on crown intaglio:
Apply 1 coat of NX3 Silane (the NX3 silane is resin containing), or apply a thin layer of bonding agent right before resin cement placement, protect from light. DO NOT light cure.
Apply 1 thin layer of “NX3” cement. Use:
Dual-cure cement: If crown is thicker than 2mm or too opaque shade
Light-cure cement: If veneer or crown thinner then 2mm.
Seat the crown preventing light exposure.