As soon as a tooth is lost the bone will degenerate and the teeth on either side will shift or tip into the empty space. If there is a tooth directly above or below the space it will over erupt, as there will not be anything to prevent it from coming out of the gum tissue. The majority of bone degeneration will occur within the first six months but will slowly continue for years. The movement of the adjacent teeth will not occur immediately; rather it will become noticeable after three to five years. How fast it occurs will depend on the density of bone in the area, your bite and how well your teeth occlude or interlock with each other.

If you have missing teeth and you do not replace them, these movements will occur. These movements may create gum problems and /or decay and could lead to the loss of other teeth. As you lose more teeth, you will be forced to chew in other areas, and this often leads to tooth fracture from overloading, excessive wear and or TMJ (jaw joint) problems. Eventually more extensive and expensive dentistry may be required in the future.

There are several reasons that you want to replace a missing tooth or teeth. A tooth has many functions some being to chew, to speak, to keep the facial muscles and tissue in a proper position, to smile, and to keep the other teeth from shifting. Once a tooth is lost this whole balance is disrupted and it leads to many various problems.

For certain teeth, such as your wisdom teeth, it is unlikely that you will need to replace them. As adults we have three molar teeth and we do most (about 80%) of our chewing from the first molar to the first premolar/canine area. About 20% is done in the second molar area, and very little is done in the wisdom teeth area. Therefore, we seldom miss or need our wisdom teeth if they are absent or removed. The second molar does at times need replacing, depending on each individual's situation.

In children, baby teeth maintain space for the developing permanent teeth. If baby teeth are lost early, crowding problems may be unnecessarily created and may require orthodontic treatment to correct. Baby teeth are generally not replaced with another tooth; however, an appliance (space maintainer) is often placed until the permanent tooth erupts.