Can a dentist work without establishing an office first?

Yes and no: First a graduate of a dental school has to take boards in most states and acquire a license to practice in the state he or she wants tp practice. This person can work for someone else in their office. Due to the type and complexity of the materials and equipment needed to practice, this person needs access to these in order to do dental work.

Yes: They could work for another dentist in their office. They could work in a community clinic, hospital or in the military as a dentist.