"I have an exam with you on Monday morning. I am hoping you can help me."
Those were the opening words of a letter I received from a new dental patient. When a patient sends a letter like this before an appointment, it is clear they are seeking two things: they want answers, and they want options. This letter laid out a lot of information that gave me insight into her condition and let me consider treatment options in advance.
Let’s review the letter and see what we can learn from her history. She continues after that introduction by conveying her chief complaint...
The New Dental Patient Condition
"I have shooting pain in my left jaw joint."
Shooting pain tends to be different from muscular pain. When a patient reports shooting or stabbing pain, there is an increased chance of structural alterations at the soft and hard tissues in the TM joints.
"I am a 41-year-old female, and my jaw joints started clicking when I was in high school."
When jaw joints click, it is almost always due to a tear in the ligament that attaches the disk to the condyle. The question is whether the ligament tear is at the lateral pole or both the lateral and medial poles. The medial pole is the load-bearing portion of the joint, and the medial pole also maintains the vertical dimension at the joint level. If the disk attaching the medial pole of the disk to the condyle is torn, there is an increased risk for pain due to the lack of disk protection. There is also an increased risk of a change in occlusion due to a change in the vertical dimension of the TM joint. Lastly, if the disk does not cover the condyle during the growing years, there is an increased risk of incomplete growth of the mandible and the maxilla. In this case, the clicking occurred early and may have affected normal growth patterns1.
How Did This Patient Get Here?
"I had orthodontics when I was younger. I had an expander my parents had to turn when I was nine years old, and I had orthodontics from 11-15 years old to help fix my overbite. The first time I remember my jaw hurting was when I was using rubber bands toward the end of my orthodontic treatment."
From this history, it sounds like both the maxilla and the mandible were not growing well. The palatal expander was attempting to gain transverse dimension in the maxilla. The presentation of an overbite is typically an anterior uncoupling of the anterior teeth. If the anterior uncoupling is greater than the thickness of the disk (approximately 2mm), there is an increased risk of incomplete mandibular and maxillary growth2,3,4.
"I was told to stop using the rubber bands, and there was a discussion that I may need jaw surgery when I was older. It was a quick discussion, and my braces were removed. My joints started clicking soon after my braces were removed. I also noticed I started getting headaches around the same time. I saw a dentist who said I was grinding my teeth and suggested I start yoga classes to decrease my stress levels. The funny thing is that I did not feel I had high stress levels. I was a gymnast in high school, and I also played soccer. I got good grades and enjoyed my high school experience. Stress was not a problem, but I followed the advice and started yoga classes. It didn’t help my jaw joints, and I stopped after nine months."
The surgery discussion usually occurs because there is difficulty coupling the anterior teeth toward the end of orthodontic treatment. The difficulty coupling the anterior teeth is usually due to a loss of vertical dimension at the joint level or, more likely in many cases, a failure to achieve normal growth due to a childhood injury at the TM joint level. Unfortunately, general dentists and orthodontists have been blamed for causing structural changes at the TM joint level by changing the occlusion. While we used to think that an uneven occlusion (“bad bite”) could cause a disk displacement (“bad joint”) due to the sustained contraction of the lateral pterygoid muscle, today we realize the more probable cause of the disk displacement is a ligament injury5,6.
"I graduated high school and started college. My headaches seem to get worse after the car accident I had. Fortunately, there were no serious injuries, but my headaches became more intense, and I couldn’t open my left jaw joint as far as I could before the accident. I saw my dentist, who asked about my stress levels in college and if I was clenching or grinding my teeth a lot during finals. I told the dentist I had a 3.9 GPA, and I didn’t think I was grinding my teeth. The dentist made me my first bite appliance. It fit on my upper teeth, and it was small so that only my front teeth touched the appliance. It was supposed to help my muscles stop clenching. I was hopeful it would work since I read online that most pain in jaw joints comes from muscles."
"I was hopeful it was helping because my left jaw stopped clicking after using the appliance for three weeks. Unfortunately, it did not stop hurting, and the pain levels actually seemed to increase. After two months of wearing the appliance, it started hitting heavy on my back left teeth. I stopped wearing the appliance because I was afraid my bite would continue to change. At this point, I had to squeeze my back left teeth hard in order to get my back right teeth to touch."
The impact of cumulative injuries, such as the car accident, can continue the anatomic changes in the jaw joint. The stress discussion relates to clenching and grinding, which we know today is generally not associated with disk displacements. This is another concept that we need to rethink, given our current knowledge coming from TM joint imaging with MRI and CBCT in growing patients.
An anterior deprogrammer is an appliance that decreases muscle activity by having contact on only the anterior teeth. While this does decrease muscle activity, it also can increase joint loading. If the disk is covering the medial pole (Piper 1/2/3A/3B), anterior deprogrammers can be highly effective appliances since there is soft tissue coverage at the medial pole for the increased joint loading. If the disk is not covering the medial pole (Piper 4A/4B/55A/5B), anterior deprogrammers can be problematic, since there is no soft tissue coverage at the medial pole for the increased joint loading.
"By the time I was 28, the pain in my left jaw joint was becoming an everyday occurrence and was affecting my quality of life. To my dismay, my right joint also became tender. The right joint has clicked since high school, but I didn’t really have too much pain. I mentioned these issues when I was in for a cleaning and the dentist said there was a splint that I could get that could reposition my disk back to its normal position and the pain would resolve. I was ecstatic and couldn’t wait to get the appliance. When I came in to pick up the appliance, it was fitted, and it moved my lower jaw forward. I used the appliance and waited for the joints to get better. But instead of getting better, I was getting worse. After six weeks, I stopped using the appliance and put it in my drawer next to the appliance that covered my upper front teeth. My disappointment was real, and I was starting to get concerned that I was not going to be able to find answers to my problems."
The anterior repositioning appliance attempts to move the condyle forward under the disk by repositioning the mandible. The hope is that the displaced disk will move back into normal position and the anatomy will return to normal. More current thinking acknowledges that the ability to recapture disks is less than previously believed. Our thinking has changed given the changes we see in both the soft tissue and hard tissue. These changes in size and/or shape of the soft tissue, hard tissue, or both, make it difficult for the disk to fit over the condyle. MR imaging allows for an assessment of the anatomy to understand what treatment options have realistic chances of successful treatment.
The Expectations of This Patient
"I became excited when a friend suggested I see a dentist who specializes in surgery. I saw the dentist and had an x-ray taken. The dentist reviewed the x-ray and referred me for physical therapy. I saw the physical therapist and there was a lot of work done to try to release my facial muscles. While I did see minor improvement in my facial muscles, the joint pain was the bigger issue, and it was not getting any better."
Physical therapy can be remarkably effective when treating pain that is coming from the muscles. If there are structural alterations in the joint in addition to muscle pain, physical therapy may provide limited relief, but it may not be able to resolve the problems completely in patients with a lack of disk coverage at the medial pole.
"I called your office because a friend of mine told me that you were able to help her when she had problems with her jaw joints a few years ago. I wanted to give you a history before our consultation to provide you with any information that may help us move forward. Thank you and I look forward to our appointment."
This letter obviously comes from a highly motivated new dental patient who is looking for answers and options. Now that we understand the case better, we will talk about what happened during the patient's visit in the concluding article, A New Patient Case Study, Part 2: Diagnosis and Treatment Options.
Jim McKee, D.D.S., is a member of Spear Resident Faculty.
- Piper, M. (2020). Temporomandibular Joint Imaging. Handbook of Research on Clinical Applications of Computerized Occlusal Analysis in Dental Medicine. Vol. 2 Chapter 9. Hershey.
- Ahn, S. J., Kim, T. W., & Nahm, D. S. (2004). Cephalometric keys to internal derangement of temporomandibular joint in women with Class II malocclusions. American journal of orthodontics and dentofacial orthopedics, 126(4), 485-493.
- Schellhas, K. P., Piper, M. A., & Omlie, M. R. (1992). Facial skeleton remodeling due to temporomandibular joint degeneration: an imaging study of 100 patients. CRANIO®, 10(3), 248-259.
- Flores-Mir, C., Nebbe, B., Heo, G., & Major, P. W. (2006). Longitudinal study of temporomandibular joint disc status and craniofacial growth. American journal of orthodontics and dentofacial orthopedics, 130(3), 324-330.
- Manfredini, D., Segù, M., Arveda, N., Lombardo, L., Siciliani, G., Rossi, A., & Guarda-Nardini, L. (2016). Temporomandibular joint disorders in patients with different facial morphology. A systematic review of the literature. Journal of Oral and Maxillofacial Surgery, 74(1), 29-46.
- Cortés, D., Exss, E., Marholz, C., Millas, R., & Moncada, G. (2011). Association between disk position and degenerative bone changes of the temporomandibular joints: an imaging study in subjects with TMD. CRANIO®, 29(2), 117-126.