When a patient has a narrow upper jaw, we first determine if the narrowness is in their jaw or teeth. If the patient has a narrow jaw, we use an expander on the maxillary jaw. Incidentally, the maxillary jaw is comprised of two halves.
Studies conducted at University of Pennsylvania show that patients with a width discrepancy larger than 7 mm between either jaw have a 75% probability of having middle-aged periodontal disease. So it is important to treat any skeletal discrepancy or narrowness in the jaws.
In other cases, the patient’s teeth are narrow. Therefore, we use different types of expanders to move the teeth into a wider position. When we use expansion, we work a little more slowly, and the procedure takes more time.
Some patients may have both narrow jaws and narrow teeth. Such patients will actually be treated with both types of expanders. Instead of trying to accomplish good results using one expander.
We select the appropriate expander for each patient by first taking a radiograph of the front of the patient’s head and physically measuring the width of the jaws in comparison to the width of the head. Next, we measure the width of the teeth in comparison to the width of the jaws and compare the results with standard values that tell us which expanders are appropriate.