Should Lower Second Molars Routinely Be Replaced with Implants?

Do you miss the tooth?  Do you have a tooth opposing it?  In general it is a good idea to replace missing teeth with implants.

Implants are usually the best option for replacing missing teeth.  When a tooth is missing, it usually results in a space between two teeth.  When this type of space exists, the tooth behind the space has a tendency to tip or fall into the space.  Sometimes (especially if the missing tooth is a lower tooth) the space will cause the opposing tooth (the tooth that chews against the space) to erupt.  The space creates bite instability, and oftentimes a periodontal (gum) problem.  Left untreated, this can wreak havoc on the rest of your teeth as time goes on.

If the missing tooth is the very last tooth in the arch (2nd molar -- if the wisdom teeth are gone), then a space has net been created between teeth.  If it is a lower 2nd molar, then the upper 2nd molar may continue to erupt into the lower space causing trouble.  If the missing tooth is an upper 2nd molar, then there may not be any resulting problem caused by the space.

As a general rule, here is how/when I recommend implant treatment:

1.  Any missing teeth in front of the 2nd molars:  Replace the tooth - restore the space (usually with implant)

2.  Lower 2nd molar missing:  Pt's choice - replace with implant or leave as space.  If left alone and upper 2nd molar begins to erupt, revisit treatment options (no treatment, implant replacement, or no implant and extract erupting upper 2nd molar if all other teeth in dentition are healthy in every way)

3.  Upper 2nd molar missing:   Pt's choice - replace with implant or leave as space.  If left alone and lower 2nd molar begins to erupt, revisit treatment options.

I do not routinely replace second molars with implants.  Most patients will do fine with first molar occlusion.  This being said, it's really up to your individual situation and your preference.  Your dentist can assess your situation and provide you with the risks and benefits unique to your mouth.