I would like to phrase the action of 'hitting' someone with one's shoulder, perhaps in a single word. Disappointingly, shoulder is already an actively used verb for a different action entirely:
shoul·dered, shoul·der·ing, shoul·ders
1. To carry or place (a burden, for example) on the shoulders.
2. To take on; assume: shouldered the blame for his friends.
3. To push or apply force to, with or as if with the shoulder.
4. To make (one's way) by or as if by shoving obstacles with one's shoulders.
(Source: The Free Dictionary)
I will give out even higher praise for a solution that incorporates the specific aspect of coming into contact with the 'shouldered' person's teeth. It does not have to be a single word, although I would appreciate a concise phrase.