My molar broke below the gum line. Best option?

It is impossible to tell you definitively what to do without an xray,  but anytime a tooth is broken below the gumline the percentage of success is lowered significantly.  In these cases trying to save the tooth many times leads to the patient spending money only to have the tooth fail in a couple of years.  The best option is likely to extract the tooth and place a dental implant.  Good luck.  

Having a photograph or an x-ray would be very helpful to help determine what might be your best option. Based on your description of the situation it sounds like the tooth is compromised because of the extent of the fracture. There are times when it just doesn't make sense to do heroics and invest significant time effort and money. In cases like this, I will often suggest removing the tooth and replacing it with a dental implant.You've expressed some truly valid concerns. A dental implant would stabilize the jawbone and help better disperse chewing forces to put the root canal tooth at less risk for fracture. Also, very importantly, it will keep the opposing tooth from over erupting and creating a domino effect of problems.I hope you found this information helpful,Dr. Champagne

I've spent time at the Hunter's Ball in London.  Awesome community and friendly people all around.You seem very "informed" or your condition and potential outcomes of treatment vs. non-treatment outcomes.  If you decide to spend a lot of time, effort and money on trying to save your tooth, will your tooth still be endodontically and structurally compromised?  If so, you may want to look at just extracting the tooth and placing an implant.  If time and money is a factor in the implant, you can have the tooth extracted and have a socket preservation bone-graft placed at the time of extraction.  That will set up a beautiful site to eventually place an implant.You seem to know about teeth "drifting" if there is no adjacent or opposing tooth.  This usually doesn't happen overnight so you could have time to spread things out over time.  How long?  No one knows........ but you and your dentist can monitor things along the way to ensure a great outcome.Hope this helps!