When dentists make dentures for a patient, there are many important measurements that must be made to provide the patient with cosmetically pleasing, comfortable and functional dentures. The measurements are made using wax blocks called occlusion rims that are made from the final impressions of the patient’s jaws. Using these wax blocks the dentist will determine where to put the teeth, the proper size of the teeth and how much space between the jaws that the teeth occupy. This last measurement is called vertical dimension, and it is critical to a successful outcome.
To visualize this measurement imagine that two dots are placed on your face. One dot on the bridge of your nose, and one dot on your chin, and then with your teeth in normal biting contact the space between these dots would be a measurement of the vertical dimension. Your teeth should only touch when you swallow, very momentary, and when you are chewing food.
The rest of the time your jaw muscles are at rest and there is a space of about 6 mm between your teeth known as the freeway space. This space is very important, because it allows chewing muscles and your jaw joints to live in a comfortable harmony that puts no excess stress on either the muscles or your jaw joints. This space is a critical part of the vertical dimension and if it is not reproduced by the position of the denture teeth, your dentures will not function well and will probably click when speaking. It will also produce fatigue of the chewing muscles, and could lead to pain in the jaw joints. By carving or adding to the wax blocks this space can be determined by observing the patient with their jaws relaxed, and by having the patient speak and making sure that the freeway space is adequate.
Once this is established the other measurements of where to place the teeth, and a correct position of the teeth when biting can be made. This information is preserved with a rigid bite relation registration, which is sent to the laboratory where the denture teeth will be placed in the wax blocks in the position indicated by the dentist’s measurements.
At the next appointment the wax setup dentures will be tried in the patient’s mouth and the teeth position, esthetics, correctness of the bite and very importantly the vertical dimension will be verified. Only when all of these requirements are met will the dentures be finished in high quality acrylic resin and delivered to the patient with the expectation of comfort, pleasing appearance, and proper function.
Dr. Slaven, DDS