Idea from Japan: having 4 secretaries for a single MD.

Handle billable work, ideally making a profit. There are quite a few new dentists graduating every year, $500k could buy an office in a decent location, plus another $100k to $300k to build out the space and gain momentum.

Figure 2 to 4 receptionists, 3 or 4 dental hygienists, the doctor themselves, OP, and whoever else they hire, and you can likely hit 10 employees.

So you have say 1-2 phd level providers 4 masters 2-3 technicians 1-2 trainees and 1-2 billing and schedule people.

Each provider should be able to generate at lest income to cover 130-140% of their salary and the extra 30-40% goes to overhead and support staff salaries.