Clinical and magnetic resonance imaging findings in patients with and without improvement after mandibular manipulation and conservative physical therapy for temporomandibular joint disorders.

OBJECTIVE: This study compared clinical and magnetic resonance imaging (MRI) findings in patients with anterior disk displacement without reduction (ADDWOR) who improved to anterior disk displacement with reduction (ADDWR) vs. patients who did not improve after mandibular manipulation (MM) and conservative self-administered physical therapy (CSAPT). STUDY DESIGN: Of 15 patients diagnosed with ADDWOR by MRI, 7 improved to ADDWR (WOR-WR) and 8 did not improve (WOR-WOR). The clinical and MRI findings before and after therapy were compared in each group. RESULTS: Significant differences between the groups included age, period of awareness of trismus, and maximum mouth opening (MMO). The MRI findings revealed significant differences in the degree of ADD and morphology of the disk and condyle. MMO significantly improved in the WOR-WR group between initial and follow-up visits. CONCLUSION: Patients who were successfully treated with MM and CSAPT tended to be <30 years old, with a longer period of awareness of trismus, MMO <40 mm, a slight or moderate degree of ADD, no deformity of the disk, and no morphologic change in the condyle. Patients with ADDWOR who are treated with MM and CSAPT require an accurate clinical examination and MRI before treatment.

SAPHO syndrome of the temporomandibular joint associated with trismus: a case report and review of the literature.

Synovitis, acne, pustulosis, hyperostosis, and osteitis (SAPHO) syndrome is a disorder characterized by pustular skin lesions and osteoarticular lesions. Mandibular involvement occurs in approximately 10% of the cases, and is often seen as recurrent mandibular osteitis with bone sclerosis, mainly involving the body of the mandible in the head and neck region. Middle cranial base with temporomandibular joint (TMJ) involvement in SAPHO syndrome can be diagnostically challenging because of its rarity. Herein, we present a case of a 37-year-old man who suffered from trismus and dull pain in the left TMJ region. The initial panoramic image revealed spotty osteolysis around the left condylar head. Computed tomography (CT) images showed an osteosclerotic change in the middle cranial base including the TMJ. Magnetic resonance images showed a cortical bone change in the left TMJ without anterior disk displacement, with spotty low signal intensity in the left condyle bone marrow on T2- weighted images. Our initial diagnosis was osteomyelitis of the middle cranial base including the TMJ region. However, antimicrobial therapy, training for TMJ opening, and a surgical procedure were not effective. A detailed medical interview, careful check for skin lesions, and further imaging examinations including bone scintigraphy and chest CT led to the diagnosis of SAPHO syndrome. The possibility of SAPHO syndrome should be considered in patients suspected of osteomyelitis of the middle cranial base including the TMJ with unknown etiology.

Imaging of masseter muscle spasms by ultrasonography: a preliminary study.

OBJECTIVES: The aim of this study was to determine the effectiveness of ultrasonography (USG) in locating spasm points in the masseter muscle. METHODS: Fifteen patients with TMJ dysfunction and five healthy controls were included in the study. First clinical examination of TMJ and palpation of masticatory muscles were done. Then, the masseter muscles were examined by USG. A total of 40 masseter muscles were examined within the study. RESULTS: Spasm points were observed as limited isoechogenic areas within normal heterogeneous muscle tissue. Within the 30 masseter muscles of patients with TMJ dysfunction, a total of 14 spasm points were detected clinically and 18 spasm points were detected ultrasonographically. No clinic or sonographic spasm point was detected in the masseter muscles of healthy controls. CONCLUSION: USG demonstrated in detail the internal structure of the masseter muscle in all patients and provided precise localization of the spasm points on the muscle. This is a preliminary study, showing that changes in muscle internal structure can be visualized with USG.

Image-based Data Mining to Probe Dosimetric Correlates of Radiation-induced Trismus.

PURPOSE: To identify imaged regions in which dose is associated with radiation-induced trismus after head and neck cancer radiation therapy (HNRT) using a novel image-based data mining (IBDM) framework. METHODS AND MATERIALS: A cohort of 86 HNRT patients were analyzed for region identification. Trismus was characterized as a continuous variable by the maximum incisor-to-incisor opening distance (MID) at 6 months after radiation therapy. Patient anatomies and dose distributions were spatially normalized to a common frame of reference using deformable image registration. IBDM was used to identify clusters of voxels associated with MID (P ≤ .05 based on permutation testing). The result was externally tested on a cohort of 35 patients with head and neck cancer. Internally, we also performed a dose-volume histogram-based analysis by comparing the magnitude of the correlation between MID and the mean dose for the IBDM-identified cluster in comparison with 5 delineated masticatory structures. RESULTS: A single cluster was identified with the IBDM approach (P < .01), partially overlapping with the ipsilateral masseter. The dose-volume histogram-based analysis confirmed that the IBDM cluster had the strongest association with MID, followed by the ipsilateral masseter and the ipsilateral medial pterygoid (Spearman's rank correlation coefficients: Rs = -0.36, -0.35, -0.32; P = .001, .001, .002, respectively). External validation confirmed an association between mean dose to the IBDM cluster and MID (Rs = -0.45; P = .007). CONCLUSIONS: IBDM bypasses the common assumption that dose patterns within structures are unimportant. Our novel IBDM approach for continuous outcome variables successfully identified a cluster of voxels that are highly associated with trismus, overlapping partially with the ipsilateral masseter. Tests on an external validation cohort showed an even stronger correlation with trismus. These results support use of the region in HNRT treatment planning to potentially reduce trismus.

Clinical and Radiographic Characteristics as Predictive Factors of Swelling and Trismus after Mandibular Third Molar Surgery: A Longitudinal Approach.

Introduction: Factors that contribute to swelling and trismus are complex, and they are originated by surgical trauma. The aim of the present study was to determine whether clinical and radiographic factors could predict the level of swelling and trismus after lower third molar surgery, through longitudinal approach. Methodology: A prospective longitudinal trial was carried out. Forty-five patients of both genders with clinical and radiographic diagnosis of asymptomatic mandibular impacted third molar and with no intake of analgesic or anti-inflammatory drugs 12 h prior to surgery were recruited and evaluated in a 72 h follow-up period. A mixed repeated measures model and backward and restricted maximal likelihood methods were used to analyze the data. Results: Male gender, body mass index (BMI), the relation to the lingual and buccal walls, and age were determinants for predicting postoperative swelling and for exerting a significant influence (P < 0.05). Conclusions: This study suggests the association of male gender, the relation to lingual and buccal walls, BMI, and age with measurement of swelling.

Aggressive fibromatosis in the infratemporal fossa presenting as trismus: a case report.

BACKGROUND: Here we report a very rare entity of an infratemporal region aggressive fibromatosis in a 23-year-old Tharu man who had presented with the symptoms of painless but progressive trismus. CASE PRESENTATION: We describe a case of aggressive fibromatosis in a 23-year-old Tharu man. Radiological imaging as well as an immunohistochemistry panel from a biopsy indicated a diagnosis of an aggressive fibromatosis. Since there was no aggravation in his trismus following surgery and because of his poor socioeconomic status, he was advised to attend regular follow-up visits without any adjuvant therapy. CONCLUSIONS: This case report adds to the notion of keeping the differential diagnosis of an aggressive fibromatosis in all patients presenting with progressive but painless trismus. The characteristic imaging findings as well an immunohistochemistry panel will help us clinch the correct diagnosis.

Masseter and temporalis muscle electromyography findings after lower third molar extraction

Background: The main clinical application of electromyography is to detect abnormalities in muscle function, to assess muscle activity for purposes of recruitment, and in the biomechanics of movement. Objectives: To analyze electromyography (EMG) findings for masticatory muscles during chewing following surgical extraction of lower third molars, and to determine any correlation between pain, inflammation, trismus, and the EMG data registered. Material and Methods: This prospective study included 31 patients. Surface EMG was used to study masseter and temporalis muscle function before lower third molar extraction and 72 hours and seven days after surgery. Clinical variables, pain, inflammation, and trismus were registered before and after surgery. Results: Studying the area and size of the masticatory muscles, higher values were found for temporalis than masseter muscles, regardless of the surgical side, which points to the greater involvement of the temporalis muscle in mastication. Comparing the side where surgery had been performed with the non-surgical side, a sharp and statistically significant reduction in amplitude and area were noted on the surgical side reflecting major functional affectation. One week after surgery, amplitude and area had almost returned to base-line values, indicating almost complete recovery. While pain decreased progressively after surgery, inflammation peaked at 72 hours, while mouth opening reached a minimum at this time, returning to normality within the week. Conclusions: Surgical extraction of lower third molars produces changes to electromyography activity that are more evident during the first hours after surgery and closely related to the intensity of pain suffered and the patient's inflammatory responses, although they are not related to mouth opening capacity (AU)

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A study on the post-radiotherapy changes of temporomandibular joint in nasopharyngeal carcinoma patients.

OBJECTIVE: Radiation-induced trismus, which is resulted from damage of the temporomandibular joint (TMJ), is one of the common late complications in nasopharyngeal carcinoma (NPC) patients after radical radiotherapy. This study investigated the radiation induced TMJ changes using ultrasonography in post-radiotherapy (post-RT) NPC patients. METHODS: 114 NPC patients, who had completed radiotherapy for more than 4 years, were assessed with the maximum incisal distance (MID) and ultrasonography examination of TMJ from which the maximum disc thickness of the joint disc, the condyle irregularity (CI), joint vascularity (JV) and relative muscle echogenicity were assessed. The same assessments were conducted on 100 age-matched normal subjects. The results were compared among the patients with and without trismus, and the control group. The mean doses to the TMJ were estimated using the treatment planning system and their correlation with the magnitude of MID was also investigated by the Pearson correlation test. RESULTS: 39 out of the 114 patients (34.2%) presented with trismus. The average mean TMJ for all patients was 41.4 Gy, in which patients with trismus was significantly higher than patients without trismus (p = 0.017). The mean MID of patient group was significantly lower than control group (p < 0.001). The mean maximum disc thickness of the patient group was significantly smaller than the control group, whereas the mean CI and JV were significantly higher in patient group. For relative muscle echogenicity, a higher percentage of the control group showed hyperechoic pterygoid muscle than the patient group. The mean total dose to the TMJs for the patient group was 41.4 Gy and there was a mild negative correlation between the mean TMJ dose and the MID (r = -350). CONCLUSION: The TMJ in post-RT NPC patients showed reduction of disc thickness, increase of CI and JV. Patients with trismus demonstrated thinner disc thickness and higher JV than those without trismus. Advances in knowledge: Our study was the first cross-sectional comparative study involving over 100 patients and normal subjects that used ultrasound to assess the radiation-induced morphological changes of TMJ. Post-RT TMJ changes characterized by the reduction of disc thickness, increase of CI and JV were detected in the NPC patients. The parameters used in this study were able to detect the morphological differences between the patient group and control group, and therefore can be effectively used to monitor the TMJ condition of post-RT NPC patients.

Restricted Mandibular Movement Attributed to Ossification of Mandibular Depressors and Medial Pterygoid Muscles in Patients With Fibrodysplasia Ossificans Progressiva: A Report of 3 Cases.

Fibrodysplasia ossificans progressiva (FOP) is an extremely rare genetic condition characterized by congenital malformation and progressive heterotopic ossification (HO) caused by a recurrent single nucleotide substitution at position 617 in the ACVR1 gene. As the condition progresses, HO leads to joint ankylosis, breathing difficulties, and mouth-opening restriction, and it can shorten the patient's lifespan. This report describes 3 cases of FOP confirmed by genetic testing in patients with restricted mouth opening. Each patient presented a different onset and degree of jaw movement restriction. The anatomic ossification site of the mandibular joint was examined in each patient using reconstructed computed tomographic (CT) images and 3-dimensional reconstructed CT (3D-CT) images. A 29-year-old woman complained of jaw movement restriction since 13 years of age. 3D-CT image of the mandibular joint showed an osseous bridge, formed by the mandibular depressors that open the mouth, between the hyoid bone and the mentum of the mandible. A 39-year-old man presented with jaw movement restriction that developed at 3 years of age after a mouth injury. 3D-CT image of the jaw showed ankylosis of the jaw from ossification of the mandibular depressors that was worse than in patient 1. CT images showed no HO findings of the masticatory muscles. To the authors' knowledge, these are the first 2 case descriptions of the anatomic site of ankylosis involving HO of the mandibular depressors in the jaw resulting from FOP. In contrast, a 62-year-old bedridden woman with an interincisal distance longer than 10 mm (onset, 39 years of age) had no HO of the mandibular depressors and slight HO of the medial pterygoid muscle on the right and left sides. These findings suggest that restricted mouth opening varies according to the presence or absence of HO of the mandibular depressors.

Fate of the Coronoid Process After Coronoidotomy and Its Effect on the Interincisal Opening: A Clinical and Radiologic Assessment.

PURPOSE: Coronoidotomy (surgical detachment of the coronoid process from the mandibular ramus) is used to treat several conditions, including coronoid hyperplasia and temporomandibular joint (TMJ) ankylosis. The stability of the outcome, however, is considered questionable because of the risk of reattachment of the coronoid process. This study aims to radiographically and clinically evaluate the long-term anatomic and physiological outcome after coronoidotomy. MATERIALS AND METHODS: In 17 patients with unilateral TMJ ankylosis, 25 coronoidotomies were performed as an additional maneuver to relieve trismus after ankylosis release. Radiologic evaluation was performed immediately and 1 year postoperatively with panoramic radiography and computed tomography to assess changes at the coronoidotomy site. Clinical assessment included measurement of the interincisal distance at the 1-, 3-, 6-, and 12-month postoperative visits. RESULTS: A sharp osteotomy margin with a 3- to 10-mm gap between the ramus and coronoid process was observed immediately postoperatively in all cases. After 1 year, 23 cases (92%) showed partial (n = 5) or complete (n = 18) osseous union to the mandibular ramus, whereas in 2 cases, no evidence of fusion was observed radiographically. The mean interincisal opening achieved at 1 year was 33 mm. CONCLUSIONS: Coronoidotomy is an effective but more straightforward adjunct to arthroplasty than coronoidectomy (surgical excision of the coronoid process) in the management of TMJ ankylosis, with achievement and maintenance of adequate postoperative mouth opening.

First case of bilateral coronoid hyperplasia in monozygotic twin sisters-a new aetiological perspective?

BACKGROUND: Mandibular coronoid hyperplasia is a rare condition associated with gradual reduction in mouth opening. Its aetiology is unknown but increased temporalis activity, endocrine stimulus, trauma and familial causes have been proposed. CASE REPORT: In this article, we present a case of bilateral coronoid hyperplasia presenting with limited mouth opening in 16-year-old Caucasian twin sisters. DISCUSSION: This report gives a new perspective to the aetiology of coronoid hyperplasia since it describes its occurrence in monozygotic twins and hence provides a strong argument in support of a genetic aetiology.

Radiation-induced temporo-mandibular joint disorder in post-radiotherapy nasopharyngeal carcinoma patients: assessment and treatment.

Nasopharyngeal carcinoma (NPC) is endemic in southern China, and its incidence in Hong Kong is relatively high. Radiotherapy is the mainstay treatment for NPC due to its relatively high radiosensitivity and deep-seated anatomical position, which is not readily accessible by surgery. Although the technique of radiotherapy in NPC has been advancing and offers promising treatment outcome, complications around the irradiation areas are inevitable and the quality of life of the post-radiotherapy patients is often compromised. Trismus, which is defined as the restricted mouth opening or jaw movement due to the disorder of temporo-mandibular joint (TMJ), is one of the possible late complications for radiotherapy of NPC and is found in 5-17% of the post-radiotherapy (post-RT) patients. Trismus at early stage may only affect the speech, but in severe cases nutritional intake and oral hygiene condition may deteriorate seriously. This article reviewed the possible causes of radiation-induced TMJ damage, the various assessments including imaging modalities and possible treatments. The conclusion is that the availability of simple, yet effective examinations for trismus is essential for delaying the progression and restoring TMJ functions. Although there is no absolutely effective treatment for trismus, many supportive, restorative and palliative management are possible under different clinical situations.

Using pneumo-computerized tomography as a quantitative assessment of result in submucous fibrosis patients treated with surgical release and free flap reconstruction.

OBJECTIVE: This study investigates the efficacy of oral submucous fibrosis release and free flap reconstruction. STUDY DESIGN: Pneumo-computerized tomography (pneumo-CT) was used to evaluate postoperative changes in the buccal vestibular volume during maximum blowing. METHODS: From March 2003 to November 2008, 9 patients underwent 18 microvascular flap reconstructions after oral submucous fibrosis release. The preoperative and postoperative buccal vestibular volumes were determined by capturing the air density in the selected region on CT images, which were composed of 0.75-mm-thick slices that were then summated using analysis software (Biomedical Imaging Resource; Mayo Foundation, Rochester, MN). RESULTS: Postoperative results were measured for a mean follow-up period of 15 months (range, 6-36 mo). There was significant improvement in the interincisal distance from 12.44 (8.35) mm preoperatively to 32.56 (7.322) mm postoperatively (P = 0.000). There was an accompanying significant increase in the buccal vestibular volume from 5.66 (3.92) mL preoperatively to 9.38 (4.96) mL postoperatively on the right side (P = 0.032) and from 6.44 (4.20) mL preoperatively to 9.64 (4.65) mL postoperatively (P = 0.048) on the left side. CONCLUSIONS: Adequate release of the mucosa and resurfacing with a free flap can increase the interincisal distance and improve the maximal buccal vestibular volume. Air-contrast pneumo-CT studies demonstrate an improvement in buccal mucosal elasticity.

A rare isolated unilateral myositis ossificans traumatica of the lateral pterygoid muscle: a case report.

INTRODUCTION: Myositis ossificans traumatica is a pathological condition characterized by the extraskeletal formation of bony tissue, induced by violent or repeated trauma. CASE PRESENTATION: A 30-year-old Italian man, after surgical treatment for multiple facial fractures, presented with a progressive limitation of mouth opening. A computed tomography scan showed a significant calcification of the fibers of the left lateral pterygoid muscle. The working diagnosis was myositis ossificans traumatica of the left lateral pterygoid muscle. Surgical excision was suggested but not performed. Our patient underwent physiotherapy treatment resulting not in a complete restoration of mandibular movements but in an acceptable recovery of mouth opening. CONCLUSIONS: Myositis ossificans is a rare complication that can be caused by muscle trauma. Therefore, special attention should be paid to surgical trauma. In the present case, surgical excision was considered, in accordance with the literature, and suggested to our patient, but he declined due to the absence of any pain or any significant limitation to his daily life activities. He therefore underwent physiotherapy treatment, in line with our unit's guidelines, resulting not in a complete restoration of mandibular movements but in an acceptable recovery of mouth opening.

Incidence and clinical significance of zygomaticomaxillary complex fracture involving the temporomandibular joint with emphasis on trismus.

Trismus is frequently a sequel of temporomandibular joint (TMJ) involvement in a zygomaticomaxillary complex (ZMC) fracture. Although trismus is commonly observed in patients with ZMC fracture, continuous follow-up examinations of their degree of mouth opening have rarely been documented. The aim of this retrospective study was to determine the incidence and clinical significance of ZMC fracture involving the glenoid fossa or articular eminence of the TMJ with an emphasis on trismus. The medical and computed tomography (CT) imaging data of 28 patients with ZMC fracture treated by oral and maxillofacial surgeons (OMFSs) (OMFS group) and 174 patients with ZMC fracture treated by surgeons other than OMFSs (non-OMFS group) between May 2002 and May 2006 were reviewed. Maximal interincisal opening (MIO) less than 35 mm or three-finger width was considered limited mouth opening and indicative of trismus. Preoperative CT imaging data indicated that about 64% (18/28) and 50% (87/174) of the patients in the OMFS and non-OMFS groups, respectively, had a ZMC fracture involving the TMJ. Among these OMFS patients, 17 (94.40%) patients had limited mouth opening (MIO range, 7-33 mm) preoperatively, which improved markedly postoperatively. Among the non-OMFS patients with such fractures, 42 (48.3%) patients had trismus preoperatively and two retained trismus postoperatively. Lack of proper preoperative CT images, inadequate postoperative follow-up protocol, and/or neglect by patients and medical staff could influence the outcomes of ZMC fracture involving the TMJ. We make recommendations for reducing the risk of complications subsequent to ZMC fracture involving the TMJ.