Two key phrases are overbite that is biting OVER, (vertical)
and overjet or how much the teeth jet out over and horizontal to the
lowers.

People like a deep overbite. It is sexy.

Joel

I personally don't use those terms, and use other discriptors to
clasify overbites, however I think the complete overbite is talking
about a 100 percent overbite in otherwords there is no lower anterior
teeth showing (the upper teeth cover them over completely)  A 100% deep
bite.  The incomplete overbite is actually an openbite (0%) (when there
is spce between the lower and upper teeth)  I am sure you can find
pictues on line by searching "deepbite" and "openbite"

Usually we want to finish patients around a 30% overbite, however this
is not atinable on all cases and in some cases it not the desired
result.

Dr. Braces

Just to clear up somehthing also for the general public which may read
this.  Most people think of when their teeth "stick out" they have a
larger overbite, but this may or may not be the case, as for some
reason I have found that the word overbite to them seems to be
associated with what is actually an OverJet.

Overbite refers to the amount of overlap of the top teeth have with the
bottom (in an up-down direction)
Overjet refers to the amount of room between the top teeth and the
bottom teeth in a front back direction.

Dr. Braces