Does my old silver filled molar really need a root canal and crown?

[S.U.]

My Dentist retired, so I used a new one who told me that my silver filled molar on the bottom right is leaking, but will be best with a root canal and crown since the filling is already deep. Is this really true? Do I really need a root canal even though the nerve is currently fine? Why can't I just get another filling, instead of needing this tooth ground down. The filling is 9 years old, but this Dentist claims that my old Dentist should have told me that any replacement would be with a root canal and crown? The silver looks ugly when I yawn, but I would rather have it-even a bigger filling than need a crown. I have attached the xray showing the filled tooth. I was also curious if the Dentist drilled the back half of my tooth for a cavity there too, or was it just to hold the filling in for the cavity I definitely had in the front half of the tooth?

 

[rob wain]

In my opinion and from your description there is no reason for you to have a root filling and certainly not a crown.
If the tooth is leaking then a composite filling (possibly porcelain) is more appropriate.
If the dentist has done further tests and has more detailed radiographs then he may have based his recommendation on those. However from the information you have provided I wouldn't recommend such an aggressive treatment