Broken tooth to gumline - do I need to see a dentist asap and can it be fixed without extraction? (photo)

Yes, this is an emergency and you should see your dentist ASAP.Without an X-ray and proper clinical evaluation, its impossible to guess what your tooth will need, but it does look restorable (it can be saved).  Ask your dentist about an Emax Onlay if your tooth does not need a root canal.  If Root canal is indicated, an Emax crown will be your best bet.Steven M. Goldy, DDS

Well, you need to see dentist for the treatment because if you avoid this now may be in future you will face major problem. Also it needs dental x-ray so that it is easy to suggest you a treatment. 

A picture is worth 1000 words.  Your tooth is not truly broken down all the way to the gumline there is still a good amount of tooth structure left per the photograph. In order to avoid extraction you will want to see the dentist right away. It could be as simple as a crown, but may require a root canal.  If you decide to delay treatment, this will likely turn into an extraction and eventual. I urge you to seek care quickly. 

It is very possible that you will need a root canal and a crown but it is impossible to determine without an x-ray and additional views of the tooth. I suggest getting in with your dentist ASAP.

Without an xray, we can't tell what the damage IS, so can't really say what the solution would be.  Teeth break for a reason, usually decay.  It is likely savable, but would require at minimum an onlay, likely a crown, possibly root canal therapy.  The fee for all that may make a dental implant a better option for the same cost but longer durability.