What is the difference between the dual-cured resin cements Duo Link and BisCem by Bisco?

There is a major difference between these two cements. Duo-Link (Bisco, Inc.) is a traditional dual-cured resin cement, where you would use separate dental adhesives and primers first, then place the restoration with the resin cement, light-cure, etc. This type of cement is typically used when bonding veneers, or feldspathic all-ceramic crowns, where the highest bond possible is desired. BisCem (Bisco, Inc.) is in the new category of “self-adhesive” resin cements. With this type of cement, the adhesive is included within the cement, so there is no extra adhesive step. It is a resin cement, but its bonds to enamel and dentin are much lower than the traditional dual-cured resin cements with the separate adhesives. Therefore, self-adhesive resin cements are useful for any traditional PFM or gold crown, the lithium disilicate ceramic restorations such as IPS e.max or zirconia-based ceramics, but you should use them with caution  to bond veneers or any other low-retentive ceramic restoration.