Nesbits are not meant to be used for chewing because food can get stuck on them, pop them out and that's when you could choke on it. If swallowed, the acrylic ones are more likely to pass through the digestive tract without getting caught as with the metal ones. Also, they have to fit snug or that too cause them to fall out and it's the choking thing that could be a problem. However, if you only eat soft foods while you have it in and you try not to chew on that side, you could leave it in with some confidence. Most of the patients that I know who have nesbits remove them during eating and then just pop them back in when they are done.
Chewing is not the real reason for a nesbit because you can usually chew most foods okay without one. The reason to have this appliance is to prevent the adjacent teeth from tilting in towards that open space which can mess up your bite and also to prevent the biting tooth (the tooth directly above or below this space) from drifting up or down into this space. Nesbits are space holders, for lack of a better definition, and for esthetics.
Removable partial dentures are designed for chewing as well as space holders and esthetic reasons.
Given the two other root canaled teeth, #2 and 4 in your case, it is not ideal to put an implant in between these two compromised teeth. It is also not ideal to put a three unit bridge there which would mean grinding down the two root canaled teeth. The trauma from the drilling on these guarded and fragile teeth could set off a huge problem. Also, when one or both of these teeth needs to be removed, the entire bridge becomes useless. It's usually not recommended because it's just not stable.
Originally Posted by spork
Hmmm... unfortunately, the only reason I want a tooth there is for chewing. The missing tooth is far enough back that you don't notice it's missing.
In the link you provided I see:
"The design of the new flexible plastic framework takes the danger out of an accidental swallowing of the appliance. In the event that someone did swallow one, it is unlikely that any damage could be done to the lining of the digestive system."
So it sounds like maybe the swallowing hazard has become less of an issue.
It also says:
"Dentists used to build Nesbits for their patients all the time. They were composed of a single denture tooth (usually a back tooth) between two cast metal clasps which attached onto the teeth on either side of the missing one."
I would have thought it was intended for chewing if it's typically used on a back tooth, but then I've never even heard of one until today.
Given the root canals on the two neighboring teeth, it sounds like the best bet is to leave a hole there - right?