
Self-Etching Self-Priming resin cements, better known as “cem’s”, are a very popular option for placing indirect restorations. Dentists have jumped on board with this category of cement because of it’s many advantages. One of the major advantages is ease of use. The original packaging is a capsule that is activated and then mixed in an automatic mixer similar to a triturator. Newer versions of these cements come in syringe like dispenser with automixing tips. These cements are known for low post operative sensitivity, and their translucency makes them perfect for seating all ceramic crowns where esthetics are paramount. Clean up can be accomplished easily if we get the cement in the early stages prior to final set.
These cements generate bond strengths of between 12-18 MPa, making them designed for restorations that have retention and resistance form, ad materials that do need need the bond for strength. One of the common issues encountered is using SESP resin cements for partial coverage restorations that are totally dependent on the bond for retention, and having the restoration come uncemented prematurely. This type of restoration is best placed with dual cure or light cure resin cements that have higher bond strengths.
I place many of my full coverage restorations from lithium Disilicate (e.max) to porcelain fused to metal with this category of cement and love the ease of placement and patient comfort.
Dear Dr. Brady:
Very good points regarding the cements. What kind of brand do you use in daily basis for the crowns?
For full coverage crowns I use either a resin reinforced glass ionomer, like Rely X Luting Plus, or if I want something translucent I use a SESP resin cement like Speedcem or Unicem.
Dr. Brady,
When you are cementing an emax crown with the “cems” are you HF etching and silanating the intaglio surface of the crown prior to cementation?
You do not need to etch or silanate the lithium disilicate if you have retention form and are using a “cem” cement.