Last month I got on a roll discussing the removable prosthesis as a viable and important option in the armamentarium to replace missing teeth. I would like to continue the discussion of removable partial and complete dentures. When I completed last month’s article I was discussing the differences between porcelain and acrylic denture teeth. It is well documented that the acrylic denture tooth will wear at a much higher rate when it is chewing against either a natural tooth or another acrylic denture tooth.
I would like to continue the discussion of what happens when a denture wears down and the biting surface of the teeth gets flattened off. Let’s start with a quick overview of how the teeth chew together on a denture. The bite is very different on a denture when compared to a full set of natural teeth. When we dentists design a bite for dentures the front six teeth do not contact the lower front six teeth. The back four teeth on each side top and bottom fit very intimately. This design is so the denture stays stable in the mouth. The way someone with dentures chews their food is very different from someone with natural teeth. The bite for a denture wearer is designed to hold the denture in place and not move around. There are many factors that can contribute to a loose denture but having a stable bite is the most important factor in keeping it stable.
So what does all of this boring bite discussion have to do with the type of teeth? As I mentioned before the acrylic teeth wear down quicker than porcelain teeth. If the back teeth are the only thing contacting and those teeth are acrylic and those acrylic teeth wear down then soon one of the rules of design for a denture bite will be violated. Due to the wear on the back teeth soon the front teeth will be touching. Once the front teeth touch a situation called Kelly’s Triad occurs. As the name implies Kelly’s Triad is a three part phenomenon that occurs with all three parts occurring together. The first is the destruction of bone in the upper front jaw due to the biting forces of the denture. As the bone is destroyed in the upper front the denture will sink upward. The lower will then over close up to meet the upper and the third part is the downward growth of the back upper bone. This leaves a very difficult situation for the dentist to restore.
Please don’t think that I am saying that all acrylic denture teeth are bad. That is not my point. The point is that once the denture has been made most people think they are done with seeing a dentist. In truth it is best for a denture wearer to have the denture bite evaluated at least once a year. If there are signs that the bite is off or there is wear, these problems can be attended to right away. Also, it is important that every patient have an oral cancer screening at least once a year.
For all of my team I would like to take the opportunity to thank all of you who participated in this years Smiles For Life children’s charity fundraiser. I am pleased to share that our office raised $8800 for children’s charities. Half of the money stays right here in Auburn and will benefit the Auburn YMCA scholarship fund. This fund is to assist underprivileged children be able to utilize the vast array of services at the YMCA. The remainder of the donations goes to the Garth Brooks Teammates for Kids foundation.