Most people assume that all missing teeth other than wisdom teeth should be replaced. After all, when a tooth is extracted, the teeth around it may shift, and we do need our teeth for proper chewing. Most often, replacing a missing tooth is the best option.
Although this is usually the case, not every missing tooth needs to be replaced. As a dentist in New York practicing for over 28 years, I have found that for some patients tooth replacement is not their best option. If you have had an extraction of a back tooth many years ago, chances are that any shifting that will take place has taken place. Often the teeth around an extraction site shift only as much as the patient's occlusion allows. The teeth opposing the teeth adjacent to the extraction site can sometimes keep them in place.
Also when some of my elderly patients, whose health status can be fragile, lose teeth, I do not always recommend replacing a missing tooth. If they have an intact first molar and they lose their second molar, there really is no reason they have to replace it. Sometimes, not replacing it will allow the opposing second molar to extrude. In an elderly patient, this is not such a big deal.
For those with delicate health status, what is most important dentally, is that they are free of dental infections, since these infections may pose a risk to their overall health. Replacement of teeth can be of secondary importance,especially if the proposed method of replacement would require many lengthy dental visits.
If on the other hand a patient has an extraction and assumes that he will replace the tooth with an implant at a much later time, he or she may be disappointed, since after an extraction, the bone around the socket tends to narrow with time. If too much time elapses, their may not be enough bone at the extraction site to allow placement of an implant.
When one of my patients loses a single tooth, I discuss the options with them and we decide together whether it a tooth replacement would be in their best interest.