The restricted mandibular opening (TMJ) problem can be often mis-iagnosed and mis-treated when the underlying problem is really an undetected “elongated coronoid hyperplasia” resulting from abnormal hyperactive temporalis anterior muscle activity due to a posterior abnormal jaw closure patterns. Patients can exhibit decreased mandibular opening and may have a limited lateral excursions due to a hinging or locking into the zygomatic process or even fuse with it. Patients are usually painless unless an attmpt is made to increase the restricted opening. Limited opening could be due to connective tissue disease (e.g., scleroderma, lupus) following (capsular fibrosis – fibrous or osseous) and skeletal abnormalities (e.g coronoid hyperplasia). In unilateral situations, a decreased lateral excursion will occur toward the contra-lateral side.
Anterior open bites can also be mis-diagnosed and mis-treated when the underlying neuromuscular causes are not acknowledged and not recognized. Abnormal tongue habits as well as abnormal swallowing patterns will occur when there is an imbalance of masticatory muscles activity present and lack of proper occlusion to support proper intra oral tongue posture.
A 26 year old caucasian male presented with severely restricted jaw opening.
- Pain in jaw joints – bilateral
- Pain in neck – bilateral
- Pain in shoulder – bilateral
- Headaches – bilateral
s in ear – left
- Inability to open his mouth – 21.8 mm incisal edge to incisal edge
- Difficulty to chew, swallow, load snoring
- Constantly tired
- Mouth breathing at night
- Dry mouth
- Severe canker sores – ulcerations, (Sores develop 2-3 times monthly contributing compromised eating, sleeping and day time awake work habits).
- Flexirl seems to help
- Inability to eat
Previously he has seen various doctors, physical therapists and medical doctors. Some MD’s thought his problem was attributed to possible connective tissue disorder. See X-ray of lungs.
During consultation patient was asked to protrude the mandible forward – no movement- abrupt hard end restriction was noted!
Clinical Findings on Brief Consultation:
- Patient has severely restricted opening
- No protrusive movement
- Severely limited left and right excursive movement.
- No end give on finger pressure.
- ROM severely restricted – 21.8 mm max open.
- At age 17 he could move mandible more freely.
- 10 years later no mandibular movement.
- Lower facial features show atrophic appearance.
- Patient very alert, active.
- Considering consulting to cope with situation.
- Loosing weight and can’t eat effectively.
- Discussed etiology, treatment options.
Patient had previous surgery of maxillary to correct anterior open bite in year 2000. It relapsed in 2001.
- Patient spent $45,000
- Insurance did not pay
8-31-00, Age 23 (Anterior Open Bite – Before Surgery)
10-30-00 (After Maxillary Surgery to Close Anterior Open Bite)
11-7-01 (Tomograms of Left and Right TMJ)
11-7-01 (Lateral Cephalogram After Anterior Open Bite Closure Surgery)
11-10-04 (Relapse Anterior Open Bite After Surgery) – Note: Un-diagnosed elongated coronoid process of both left and right sides indicative of coronoid hyperplasia.
Patient was immediately referred to neuromuscular Oral Surgeon for evaluation and treatment for bilateral coronoidectomy.
Scientific Studies Have Shown:
The results of the Levandoski analysis (Evaluation of the role of coronoid hyperplasia in recurrent unilateral temporomandibular joint (TMJ) ankylosis using the Levendoski analysis) was useful in the correct categorization of 16 patients. Selected surgical treatment approach were also successful. Studies show there was no recurrence in any of the cases. Although the initial limitation of mouth opening shows some tendency to diminish, yet the relapse (recurrence) was even less when an ipsilateral coronoidectomy was performed. The decision to perform an ipsilateral coronoidectomy based on our criteria also proved successful. There was a significant improvement in maximal interincisal distances, and protrusive excursions for group II patients. Coronoidectomy did not much affect lateral excursions. Elongated coronoid processes were more frequently associated with males, older aged subjects, and cases of longer duration, an additional observation of this study.