I had a root canal on Fri and went back to the dentist on Mon for a temp crown and fitting for a permanent crown. The dentist took out the temp crown that the endodontist had used and grinded away most of my tooth. After that, she drew me a diagram, told me that I needed a crown lengthening and referred me to a periodontist, and informed me that she would not put on a crown if I didn't have a crown lengthening ($750 procedure which my insurance does not cover). The billing person in the dental office referred me to another dentist (in the same office) who also said I needed crown lengthening, but he said he would do the procedure free of charge.

My questions are:
1. Is a crown lengthening really necessary? My gum line is fairly high on this tooth and I think having it higher will look odd. Also, $750 is a really high cost to a grad student. It was NEVER mentioned by my dentist or anyone else when the cost of a root canal and crown were discussed.

2. Is it possible that I need a crown lengthening because the dentist grinded away too much of my tooth structure? She left very little tooth. She never discussed how much she would be removing or anything related to size prior to grinding my tooth.

3. Is a dentist qualified to do a crown lengthening? Or is it better to go to a periodontist?

4. Where can I find more information regarding crown lengthening pros and cons, both critiques and recommendations?

Thank you for your time and help.