If one were offerred a position in a well-established practice as an associate practicing in Southern California, with the likelihood to buy the practice, would you do it? My question is really aimed at asking this: Is the prospect of practicing in California worth it (given the above circumstances), considering that it seems the market there is flooded with dentist?
Do you want to live in SoCal? If so this sounds like a good way to start. You can't let the numbers (dentist to population ratio) dictate your every decision.
If people like you, they will stay in the practice and you will probably produce as much as the current owner. A startup may not be the best idea due to competition, but buying an established practice with a well thought out transition is a pretty safe way to go - even in SoCal.
I wouldn't take it b/c more than likely the owner won't sell the office or he won't sell it to you. Most older dentist like to tell newbies that they are getting ready to slow down and retire and want to sell their practice in a few years. However, they don't want to put anything on paper about a future contract or price. Even the most well intentioned well respected dentists do this, I know for a fact.
If you do take this offer make sure it is in a written contract. If not then don't do it.