Ask the Experts Answer

What is the technique for cementing/bonding an IPS e.max onlay? Both treatment for the restoration and treatment for the tooth

IPS e.max lithium disilicate is a silaca-based ceramic, so HF etching followed by silane treatment is the recommended. The bonding/cementing procedure follows:

1. Try in e.max
2. Etch the internal surface of e.max with 4-5% HF etchant for 20-25 sec. Rinse with water and dry.
3. Treat the internal surface with silane primer, 1 coat, 1 min, air dry.
   (Note: only pure silane primer is effective, such as Bisco Porcelain Primer or BisSilane.
   The silane-containing adhesive is not effective.)
4. If tooth has enamel,  etch the enamel with phosphoric acid etchant, rinse with water. 
5. Apply dental adhesive on tooth, air dry, light cure 10-20 sec. (note: always treat the restoration first, then treat the tooth structure)
6. Apply dual-cure resin cement (if it is veneer, apply light-cure veneer cement). Deat the restoration, clean the extra cement