Do I really need to replace a missing back tooth?
Usually yes, and it has nothing to do with how it looks. Teeth beside a gap tip into it, and the tooth above or below it grows out of its socket because nothing is meeting it.
Within a couple of years the bite has changed. That brings food traps, uneven wear, and often jaw soreness. The visible cost turns up later and is much larger.
Tip into the gap
Which opens spaces that trap food and decay.
Over-erupts
It keeps moving because nothing meets it any more.
Shrinks
Bone under a missing tooth wastes away, and that limits your options later.
A couple of years
Enough drift to complicate the fix and raise the price.
Why waiting makes it worse
An implant needs bone to sit in and room to sit between. Wait long enough and you lose both. The bone thins because chewing forces are what keep it, and the space narrows because the neighbors have leaned in.
Then the honest plan gets bigger. Straightening teeth back upright before replacing the tooth, or grafting bone that used to be there. Both are avoidable by acting sooner.
When leaving it is defensible
The last molar at the back with nothing behind it and nothing above it drifting is sometimes fine to leave, and wisdom teeth are not replaced at all. That is a judgement made off your x-ray, and it should be explained in terms of your own bite.
The comparison between implant, bridge and partial is laid out side by side on the tooth replacement page.
Written by Dr. Peter Bonifatto, DMD, a general dentist in Las Vegas whose practice focuses on cosmetic and restorative work. General information, not a diagnosis. What your own teeth need is decided at an exam, with x-rays.
Ask about your own teeth.
A comprehensive exam with photographs and x-rays, then a written plan with real figures you keep. Starts at $99, with no deposit on top of it.