Root Canal. Is best for a medial person.

There is no criteria to judge the valuability of a doctor's opinion unless you have a trust in his words and work. And please understand that the only thing a doctor can do to generate that trust is give a good treatment and there is no practical way to judge a doctor's opinion before that. The things you can do for that trust is check for the doctor's review and have a word with other patients for the same. The second part of your query is slightly vague. Anything is called as best not based upon the affordability of the buyer but on the quality of the material itself. So if you want to know about the best crown these are the metal free Zirconia crowns which provide the best aesthetics as well as strength. But if you want to talk about a medium range crown, a metal ceramic crown will solve the purpose sufficiently, but it will never be better than a zirconia crown in terms of quality. Regards.