Condylar distances in hypermobile temporomandibular joints of patients with excessive mouth openings by using computed tomography

Post-condylectomy orthodontic treatment for a severe asymmetrical open bite in a condylar hyperplasia patient

A satisfactory treatment of an 18-year-old lady was reported with right combination-type condylar hyperplasia (CH) in active phase. The chin severely deviated to the left, with the right gonial angle locating at a lower level. Intraorally, the lower centre line shifted to the left, the scale of which reached the width of one lower incisor. The right molar relation was mesial. Right maxillary second molar over-erupted without contact to lower teeth. There had been 2.5-mm anterior open bite (AOB) before surgery (T1) due to the tongue-spitting habit. After judging the benefits and disadvantages of all treatment alternatives, the decision was made to perform a right condylectomy and post-surgery orthodontics. Before orthodontics (T2) when the chin was positioned centred, an asymmetrical open bite occurred, caused by pre-contact between the right maxillary and mandibular second molars. Meanwhile, the AOB at T2 became 11.5mm. Orthodontic-related treatment included four premolars extraction and intrusion of bilateral maxillary molars using four miniscrews. Finally, this treatment achieved a clinically centred chin with two gonial angles at the same level. Post-condylectomy, the large AOB was resolved, together with a bilateral neutral molar relationship and alignment of the incisor midlines. Besides, the resected right condyle was covered by a continuous cortex bone and returned to the glenoid fossa. In sum, a high-challenging combined-type CH case was accomplished with impressive improvement in facial and occlusal symmetry, thanks to condylectomy and post-surgery miniscrew-assisted orthodontics.

Standard orthodontic treatment after condylectomy for patients with active unilateral condylar hyperplasia

INTRODUCTION

Unilateral condylar hyperplasia (UCH) is a progressive, nonneoplastic overgrowth of the condyle of the temporomandibular joint. For treating active UCH, a popular method combines orthognathic surgery with high condylectomy and orthodontic treatment. The goal of this study was to introduce a new method to correct asymmetry for active UCH.

METHODS

Retrospectively, 47 patients with active UCH were divided into horizontal-type, vertical-type, and combined-type. All patients were treated with condylectomy plus postsurgery standard orthodontics (CPSO) with applied miniscrews implanted in infrazygomatic crest and hard palate to intrude affected side of maxillary molars and apply intermaxillary traction for contralateral molars. Cone-beam computed tomography was taken at presurgery, postsurgery, and the end of orthodontics (T3).

RESULTS

In the vertical (n = 10) and combined (n = 28) types, deviation of the chin and the canting of the mandible and maxillary occlusal plane were significantly reduced at T3. A difference in the torque of bilateral maxillary first molar (U6) and bilateral mandibular first molar (L6) was significantly reduced at T3. The anterior, superior, and posterior joint spaces in the vertical-type and combined-type were significantly decreased at T3 compared with postsurgery. In contrast, in the horizontal-type group (n = 9), the deviation of the chin was corrected; however, the canting of the mandible and maxillary occlusal plane was significantly increased at T3 compared with presurgery.

CONCLUSIONS

CPSO restored facial and occlusal symmetry for vertical-type and combined-type active UCH and returned affected-side condyle to the glenoid fossa. However, CPSO was not suitable for treating the horizontal-type UCH.

The Effectiveness of Physical Therapy in Patients with Generalized Joint Hypermobility and Concurrent Temporomandibular Disorders-A Cross-Sectional Study

Temporomandibular disorders (TMD) consist of a group of symptoms such as: pain of temporomandibular joints, masticatory muscles or surrounding tissues, dysfunctions of TMJs’ mobility, and crepitation. The Hypermobility Joint Syndrome (HJS) manifests in the flaccidity of joint structures, an increase in the range of joint motion, and occurs more often in the young and women. The aim of this study was to present the occurrence of HJS among patients with myogenic TMD and disc displacement with reduction. The secondary goal was to assess the effectiveness of physiotherapy directed to TMD with coexisting HJS. The study involved 322 patients with symptoms of TMD. HJS was diagnosed using the Beighton Scale, which confirmed its occurrence in 26 cases. 79 subjects (7 males and 72 females; mean age, 33.9 ± 10.4 years) were selected and divided into two groups: HJS + TMD (n = 26; 2 males and 24 females; mean age, 27.1 ± 9.4 years) and TMD (n = 53; 5 males and 48 females; mean age, 37.4 ± 9.2 years). These patients completed 3-week physiotherapy management. Before and after physiotherapy, the myofascial pain severity on Numeric Pain Rating Scale, linear measurement of maximum mouth opening, and opening pattern, were assessed. To demonstrate differences between the results, the level of significance for statistical analysis was set at α = 0.05. A statistically significant improvement was obtained in decreasing myofascial pain in both groups. Coordination of mandibular movements was achieved in both groups. Generalized joint hypermobility occurred among patients with TMD. Physiotherapy directed to TMD was effective in reducing myofascial pain and restoring TMJ’s coordination also in patients with HJS.

Temporomandibular Joint Hypermobility Manifestation Based on Clinical Observations

BACKGROUND

Joint range of motion might affected by some factors like laxity and increase joint mobility. Generalized joint hypermobility and temporomandibular joint hypermobility (TMJH) are reported as risk factors for temporomandibular disorders. The aim of this study was to survey the etiological factors of TMJH and its relations to habitual status.

MATERIALS AND METHODS

In this cross-sectional descriptive study, 69 patients with TMJH were involved. After profiling personal information and medical history, the patients were divided into three groups based on their maximum mouth opening (MMO) as follow: (Light) MMO of 50-55 mm, (moderate): MMO between 55 and 65 mm, (severe) MMO >65 mm. For subjective observations, patients were asked to fill the prepared questionnaire. The objective evaluations conducted by a specialist. Finally, all the data subjected Chi-Square test by using SPSS software version 22 at a significant level of 0.05.

RESULTS

TMJH was more common in women (74.2%). The light group had significant differences with other groups in the discomfort of TMJ and TMJ sound (P < 0.05). Furthermore, sever group manifested highest percentage of masticatory pains, significantly (P < 0.05).

CONCLUSION

It can be concluded that pain in TMJ would have a correlation with MMO.

Investigating activity of masticatory muscles in patients with hypermobile temporomandibular joints by using EMG

Background

Temporomandibular joint hypermobility (TMJH) can manifest higher range of motions in mandible. The aim of this study was to investigate and compare the activity of masticatory muscle of TMJs in healthy individuals and patients with mild, moderate and severe TMJH.

Material and Methods

In this clinical study, 69 patients (between the ages of 22 to 42) with manifestation of TMJH were included. The patients were divided into three groups based on their maximum mouth opening (MMO): (light) with MMO of 50-55 mm; (moderate) with MMO between 55 to 65 mm; and (severe) with MMO >65 mm. Also, 20 healthy people with profiled tomography in the last 6 months were invited as control group (healthy) with normal MMO (<50 mm). All the groups subjected to electromyogram (EMG) in 2 steps: maximal voluntary clenching (MVC) of the jaws; and during chewing of bread by using one side of the jaws voluntary. The collected data were analyzed by Student T-test and Chi-Square tests using SPSS software version 15 at significant level of 0.05.

Results

Both TMJs of light, moderate and severe groups showed significant differences in frequency, time of activity and rest in comparison with healthy group during chewing and MVC (all p values < 0.01).

Conclusions

Masticatory muscles activity reduced in relation with the severity of TMJH and higher excessive mouth opening.

Key words:Electromyography, joint hypermobility, mouth opening, tempormandibular joint.