Root canal, is it totally necessary?

[Emmyxx]

I went to the dentist about a year ago and during a check up, my dentist noticed a cavity forming on one of my back teeth which I hadn't noticed. She filled it for me and I was on my way, and have recently now moved dentists. Yesterday was my first visit since last year, and I went because the filling had actually fallen out. She took an x-ray, asked if I was having any pain or issues with it, and then checked my teeth herself. She said she thinks I need a partial crown on it, but also say she thinks, but isn't sure, whether I may need a root canal on it as there's cavity there still! I was so surprised, as I've had absolutely no problems with it at all. No pain, no sensitivity to anything, just sadly a huge hole from where the filling has fallen out, and I've never had any problems either. She's booked me in next week for a crown prep and said she'll talk more to me about it then (how she didn't know by looking at the X rays yesterday is beyond me), but it's got me thinking, is it totally necessary? My last dentist mentioned it as a precautionary treatment I could opt to get done after my filling, or if I had any problems I could go back, but I haven't had a single problem with it at all so far, so I was really quite shocked.
Any thoughts?

 

[Enarete]

Hi Emmyxx and welcome to the forum. You obviously don't understand how your dentist came to the given diagnose and from your post it sounds like her statements sounded quite vague and insecure.
It's hard to accept a diagnose and agree on a planned treatment when you do not trust the dentist. The rule of the thumb is to follow the intuition and only do a treatment if it feels right for you and if you feel like having got and understood all information about what's happening in your mouth and why and what treatment options you have. If this is not the case, than you should get a second opinion.