Term used to describe a tooth that has not (yet) had any
surgical intervention to it's structure. That is, a tooth without a filling on it.
It's relevant when deciding whether to sacrifice a virgin tooth for the better good of the dentition. Conservation of tooth structure is now the trend.
For example, to replace a missing tooth, the teeth on either side of the gap may have to be
"prepared" for a 3-unit bridge. The teeth on either side of the gap are known as retainers or abutments. In an analogy to "normal" bridges, they form the pylons for the bridge. If they have been previously filled, then it would not be as sacrilegious to cut a preparation onto them.