Compromised Teeth

When teeth are lost or removed, not only does the bone resorb (see section on Bone Resorption), but the surrounding teeth begin to drift into the gap created by the missing tooth/teeth. This results in problems with the gums and how the teeth fit together and function (occlusion) and eventually problems with joint pain. In addition, when posterior teeth are lost, pressure is placed on the front teeth, which can cause them to splay out.

Unfortunately, attempting to replace teeth with either bridges or removable partials also compromises the health of the adjacent teeth as follows:

When teeth are cut down into pegs for bridges, the enamel is removed, leaving the spongy layer of tooth structure called the dentin. Over time, the cement retaining the bridge washes out and bacteria can seep under the bridge and decay the dentin fairly quickly. This leads to failure of the bridge and possible root canals if the decay reaches the nerve.

In addition, these teeth now bear the forces that should normally be placed on three teeth, which further weakens the structure of these teeth. It's rather like knocking one of the supports out from under the Golden Gate Bridge and expecting the other supports to bear the entire weight. It would simply fail as the other supports break down over time.

Most importantly, once the teeth are cut down for a bridge, the tooth structure can never be replaced; the long term health of the teeth is compromised and this usually results in additional treatment over time, which can be extensive and costly.

When teeth are replaced with a removable partial denture, the bone resorption is accelerated and the pressure that the partial puts on the teeth that it is hooked onto begin to loosen. Over time, the pressure can eventually torque these teeth out completely.  

If this happens, the partial must be made larger to incorporate the additional missing teeth/tooth, and it is now hooked onto other teeth than can be lost with continued pressure from the partial.