Crowns are named for what they are made of. The material changes how the crown looks, how it handles biting force, and how it is made. Cost also changes with the material and with what the tooth needs. This page describes the differences. It does not rank one material as best for every tooth.
Tooth-colored ceramic with no metal
Zirconia is a ceramic used for crowns. It is tooth-colored and has no metal layer. It is chosen when the crown needs to be strong and should not show a metal edge. The $799 program uses this material for eligible teeth. The technical name appears here so you can compare it with other options. On the rest of the site we describe it first as a strong, tooth-colored ceramic with no metal.
Porcelain and E.max
Other ceramics, including lithium disilicate (often called E.max), are also tooth-colored. They are often used when the look of a front tooth is the main goal. Smile design and esthetic E.max crowns are not part of the $799 program. Those cases need an in-person visit and a separate fee.
Porcelain over metal, and full metal
A porcelain-fused-to-metal crown has a metal base with a tooth-colored layer on the outside. The metal can make a dark line visible near the gum over time. A full-metal crown, including gold alloys, is strong and kind to the opposing tooth, and it does not look like a natural tooth. Neither of those is the crown in this program.
The right material depends on the tooth, the bite, and whether appearance or strength is the priority. That choice is confirmed at the exam, in writing, before you pay.