My last molar was extracted… Do I need a dental implant? I have received this comment/questions so many times that I decided to write a quick post about it!
Last Molars Are Not Always Needed
To be clear typically our last molar that shows in the mouth is our second molar. This is under the assumption that your wisdom tooth or “third molar” was extracted or is still under the gums.
The second molars are directly in line with our main chewing muscle called the masseter. These molar teeth tend to break because it is in an area of high-power. I even had my own second molar break a few years ago!
So do you need to replace this tooth? If it is the bottom molar and you still have the upper opposing molar than I would typically say yes. The reason for it is if you do not replace the bottom molar, the upper opposing second molar will begin to over erupt out of its socket trying to reach its old partner that got extracted.
Teeth need contact with one another.
Without contact with another tooth our teeth tend to drift. It will drift enough to where you will and up-biting your cheek and gum and can also become an interference in your bite causing “TMJ” which is really temporomandibular jaw joint problems (TMD.)
If it is the upper molar that got removed the rules are a little bit different. Some people can get away without replacing the upper second molar. This is because most people have a class I bite and the molar that is left behind on the bottom usually still has something to bite against. This is because the upper and lower molars to not aligned perfectly on top of each other. They tend to be a half tooth off. So some teeth are only biting on half of the tooth…. which is often all we need.
The lower molars to not over erupt as commonly as the upper molars do when the opposing tooth is removed. Sometimes the bone over-erupts as well causing a much more serious problem.
Upper Vs. Lower Molar Implants
Please keep in mind that not all molars need a socket bone graft and then the implant a few months later. A more advanced procedure is to have implant, bone graft and extraction on the same day.
This particular patient is missing a second molar on the bottom jaw. You can see from the side view that nothing supports the upper molar. If he takes it does not replace it, the upper tooth will eventually be lost. He elected to have me place an implant for him.
Please note that in the United States versus internationally we number teeth differently.
In the United States the second molars are numbered: 2, 15, 18, 31
These correspond to the international numbers of 18, 28, 38 and 48.
It often becomes confusing to answer questions about specific tooth numbers unless you are very specific with where you live!
Ideally, most second molars should be replaced. Nature gave you 8 molars in total. Make sure you are assessed carefully for your bite to see if you really need them are not. Most of my full mouth FULL implant reconstructions do not have second molar replacement. Why? Even though these are important teeth as long as we have the molar just in front of it… The first molar… You can have a stable healthy mouth for a very long time. But remember this is carefully planned this way.
Ramsey A. Amin, D.D.S.
Diplomate of the American Board of Oral Implantology /Implant Dentistry
Fellow-American Academy of Implant Dentistry