When Dental Patients Pop the Question ‘Can You Help Me?’

Imagine your office gets this phone call tomorrow:

“My name is Kate, and I was referred to you by my neighbor. I am 34 years old, new to the area, and I am looking for a dentist.

My biggest issue is my uneven bite. I had braces for nearly four years for a big overbite when I was 12-16. I had four teeth extracted when I had my braces. I had retainers on the upper and lower teeth after my orthodontic treatment and my teeth were great for a few years. I started to notice my bite was changing when I was in college, but I didn't think much about it. I also started to get headaches when I was in college. I get headaches 3-4 days a week now and sometimes ibuprofen helps.

My bite has gotten more uneven since my jaw joints stopped clicking. My jaw joints started clicking when I was in high school and stopped after I got married when I was 27 years old. After my joints stopped clicking, I noticed I couldn't open my mouth as much as I could when I was younger. In addition to not being able to open completely, I noticed that my left back teeth touched before the rest of my teeth. My back left teeth are the only teeth that touch when I am biting my food.

I had two nightguards made by my last dentist. The first one was a small nightguard that fit only on the front teeth. I noticed my bite started to change when I used this nightguard and my back left teeth started to contact more firmly. I also used a nightguard that pulled my jaw forward, but I stopped using it after about a month because my jaw joint hurt.
Can you help me?”

Consider what you know based on the patient's history

“My biggest issue is my uneven bite.”

We should be suspicious of joint changes since patients with malocclusions have increased odds of presenting with structural changes in the temporomandibular joint that include the medial pole (Piper 4A/4B/5A/5B¹).

“I had braces for nearly four years for a big overbite when I was 12-16.”

One of the main reasons for a big overbite is a lack of growth at the TMJ level. Lack of growth at the TMJ level typically occurs when the disk is displaced before growth is completed^2,3,4. If the overbite was present at age 12, there is an increased risk for structural changes to the TMJs that include the medial pole (Piper 4A/4B/5A/5B). In this scenario, it is likely the disks were displaced at least 1-2 years before age 12 for the overbite to express clinically.

“I had four permanent teeth extracted when I had my braces.”

Permanent teeth are usually extracted if the mandible and maxilla do not grow enough to accommodate a natural complement of permanent teeth. This is another indication of possible structural changes in the jaw joints that include the medial pole (Piper 4A/4B/5A/5B) since disk displacements in the jaw joints negatively impact mandibular and maxillary growth.

“I had retainers on the upper and lower teeth after my orthodontic treatment and my teeth were great for a few years. I started to notice my bite was changing when I was in college, but I didn't think much about it. I also started to get headaches when I was in college. I get headaches 3-4 days a week now and sometimes ibuprofen helps.”

Many patients will complete orthodontic treatment that camouflages the joint-based malocclusion.

These cases can be stable, but it is not uncommon for these patients to develop either bite instability or pain⁵. Bite changes or pain increase the likelihood of structurally altered jaw joints that include the medial pole (Piper 4A/4B/5A/5B).

“My bite has gotten more uneven since my jaw joints stopped clicking. My jaw joints started clicking when I was in high school and stopped after I got married when I was 27 years old.”

Jaw joints will click as the soft tissue (disk) and hard tissue (condyle) maintain their shape. Patients who report joints that click and stop clicking have in increased risk of structurally altered jaw joints that include the medial pole (Piper 4A/4B/5A/5B⁶).

“After my joints stopped clicking, I noticed I couldn't open my mouth as much as I could when I was younger.”

A decreased ability to open can occur when the disk is in front of the condyle and the condyle cannot translate past the disk upon opening. Joints that stop clicking have an increased risk of structurally altered TMJs that include the medial pole (Piper 4A/4B/5A/5B).

“In addition to not being able to open completely, I noticed that my left back teeth touched before the rest of my teeth. My back left teeth are the only teeth that touch when I am biting my food.”

Structural changes in the jaw joints that include the medial pole (Piper 4A/4B/5A/5B) can cause a change in the occlusion. The occlusion will typically be heavy on the side that is experiencing structural changes in the jaw joint. In this patient, there would be an increased risk of structural changes in the left jaw joint that include the medial pole (Piper 4A/4B/5A/5B).

“I had two nightguards made by my last dentist. The first one was a small nightguard that fit only on the front teeth. I noticed my bite started to change when I used this nightguard and my back left teeth started to contact more firmly.”

Assuming there are structural changes in the jaw joints involve the medial pole, an anterior deprogrammer may make the problem worse either from a bite perspective or a pain perspective. The increased load on the joints from the anterior deprogrammer may explain why the back left teeth started to contact more heavily.

“I also used a nightguard that pulled my jaw forward, but I stopped using it after about a month because my jaw joint hurt.”

The second appliance in this case sounds like an anterior repositioning appliance. If the anterior repositioning appliance moves the condyle under the disk, patients may report pain relief. If the condyle cannot move under the disk due to structural changes in the disk or the condyle, patients may report an increase in pain with an anterior deprogrammer.

“Can you help me?”

In a case such as this one, the first step is to determine a tentative diagnosis of the TMJ condition. If we assume a patient has Piper Stage 1-3B TM joints (disk coverage at the medial pole), diagnostic records will usually consist of photographs, mounted study casts and a sleep screening if necessary.

In this case, however, it appears that there may be soft/hard tissue changes at the medial pole. This would lead to a tentative joint diagnosis of Piper 4A/4B/5A/5B joints. In Piper 4A/4B/5A/5B joints, we typically will obtain TMJ imaging with MRI to assess soft tissue anatomy and CBCT to assess hard tissue anatomy in addition to photos, mounted study casts and a sleep screening when indicated.

After we understand the joint anatomy, we can offer the patient more realistic treatment options to address her concerns.

Now that we have looked at Kate's history, let's look at some clinical photos and one of her CBCT images.

References

1. Zúñiga-Herrera ID. Malocclusion complexity as an associated factor for TM disorders. A case-control study. Cranio - J Craniomandib Pract [Internet]. 2021;00(00):1–6.
2. Schellhas, K., “Pediatric internal derangements of the temporomandibular joint: Effect of facial development”. Am J Orthod Dentofacial Orthop.1993:104, 51-59
3. Flores-Mir C, Nebbe B, Heo G, Major P. Longitudinal study of TM joint disc status and craniofacial growth. Am J Orthod Dentofacial Orthop 2006:130:324-30.
4. Nebbe B, Major PW, Prasad N. Female adolescent facial pattern associated with TMJ disk displacement and reduction in disk length: part I. Am J Orthod Dentofacial Orthop. 1999 Aug;116(2):168-76.
5. Burke G, Major P, Glover K, Prasad N. Correlations between condylar characteristics and facial morphology in Class II preadolescent patients. Am J Orthod Dentofacial Orthop. 1998 Sep;114(3):328-36.
6. Piper, DMD MD, Mark. "Temporomandibular Joint Imaging." Handbook of Research on Clinical Applications of Computerized Occlusal Analysis in Dental Medicine,edited by Robert B. Kerstein, DMD, IGI Global, 2020, pp. 582-697. http://doi:10.4018/978-1-5225-9254-9.ch009