General dentists are legally able to do many of the procedures that specialists do.
They just have to make sure that they can do it as well as the specialist would do it.
The first picture is an upper molar done by a specialist.
The second one is a root canal done by a general dentist.
The thing to look for in a root canal would be a nice thick white line going as close to the end of the tooth as possible. Some root canals are very difficult and results can vary. However, more often then not, a nice thick fill, with no voids, as close to the end of the tooth as possible will lead to the best results. http://www.drellisonline.com