So based on the fact that business sense is so important, would getting a DMD/MBA be the best course of action for somebody who is the first dentist in the family and honestly wouldn't really know where to start in regards to building a practice. I heard it can take an extra year but if the numbers are that substantial then it may be a strong investment. I can always part time as a dentist while finishing up my classes.
An MBA in vast majority doesn't focus on day to day operations of a small business. The good ones focus on business theory, and overaching concepts of supply chain management, information systems, financial theory, and vision of companies and industries.
These are hardly things you need when deciding between an office employee with X qualities and another with Y qualities.
An MBA is no walk in the park at good programs. There is a reason why they are paid well in the private sector, they are valuable and the acquisition of valuable skills is usually not easy.
Think of the number of CE courses and lunches you could buy your colleagues as you discuss their business policies in comparison to the cost at big name schools.
Also, at the heart of an MBA and business in general is providing a good or service to the customer with the goal of a PROFIT. Some would argue that mentality does not fit in a dental practice.
If you look at a bulk of the big production/profit offices I bet a bulk are due to hard work and great control of expenses and patient marketing and quality work. Not because some MBA is running it.
BUT, if you can get it without costs or minimal costs and you would like to do it, then go for it!! Like you said, you could work a bit on the side to make ends meet. An extra year over your life isn't anything, just have to make sure you will see positive personal, financial, intellectual results from it.