Limitation Of Mandibular Movement Research Articles

Neurobiological mechanisms involved in sleep bruxism.

Sleep bruxism (SB) is reported by 8% of the adult population and is mainly associated with rhythmic masticatory muscle activity (RMMA) characterized by repetitive jaw muscle contractions (3 bursts or more at a frequency of 1 Hz). The consequences of SB may include tooth destruction, jaw pain, headaches, or the limitation of mandibular movement, as well as tooth-grinding sounds that disrupt the sleep of bed partners. SB is probably an extreme manifestation of a masticatory muscle activity occurring during the sleep of most normal subjects, since RMMA is observed in 60% of normal sleepers in the absence of grinding sounds. The pathophysiology of SB is becoming clearer, and there is an abundance of evidence outlining the neurophysiology and neurochemistry of rhythmic jaw movements (RJM) in relation to chewing, swallowing, and breathing. The sleep literature provides much evidence describing the mechanisms involved in the reduction of muscle tone, from sleep onset to the atonia that characterizes rapid eye movement (REM) sleep. Several brainstem structures (e.g., reticular pontis oralis, pontis caudalis, parvocellularis) and neurochemicals (e.g., serotonin, dopamine, gamma aminobutyric acid [GABA], noradrenaline) are involved in both the genesis of RJM and the modulation of muscle tone during sleep. It remains unknown why a high percentage of normal subjects present RMMA during sleep and why this activity is three times more frequent and higher in amplitude in SB patients. It is also unclear why RMMA during sleep is characterized by co-activation of both jaw-opening and jaw-closing muscles instead of the alternating jaw-opening and jaw-closing muscle activity pattern typical of chewing. The final section of this review proposes that RMMA during sleep has a role in lubricating the upper alimentary tract and increasing airway patency. The review concludes with an outline of questions for future research.

こう筋けん膜の過形成により開口障害をきたした１例

A 26-year-old woman was referred to our clinic on December 22, 1993, because of limited mandibular movement. Minor restriction of mouth opening was first noticed at 10 years of age, during a dental health examination. The patient became aware of pain and swelling of the right masseter region with decreased jaw movement at the end of November 1993.Clinically, the patient had a square face with prominent masseter muscles and mandibular angles. The interincisal opening was 22mm, with limitated lateral and anteroposterior mobility. A dense band of tissue, which became taut on maximal opening, was palpable along the anterior border of each masseter muscle.The clinical diagnosis was restricted mouth opening due to bilateral hyperplasia of the masseter muscle aponeuorses. Masseter muscle myotomy with aponeurectomy was performed bilaterally by an intraoral approach on May 18, 1995. The aponeuroses extended for three quarters of the length of the masseter muscles, down to the inferior borders of the mandible. The mouth opening improved to 46mm on incision of the aponeuroses.An examination of the patient 3 years after surgery revealed an interincisal opening of 38mm without strain.

Osteomas of the condyle associated with Gardner's syndrome causing limited mandibular movement

Osteomas of the condyle associated with Gardner's syndrome causing limited mandibular movement

開口障害をきたした両側筋突起過形成の１例

開口障害をきたした両側筋突起過形成の１例

Asymptomatic, radiologically detected chondrometaplasia in the temporomandibular joint

Asymptomatic loose bodies were detected in the temporomandibular joint of a 62-year-old woman during an examination before comprehensive dental care. The radiologic interpretation was synovial chondrometaplasia (synovial osteochondromatosis). A histologic diagnosis was not obtained, because surgery was unwarranted in view of the lack of symptoms and the benign differential diagnosis. Review of the literature revealed 62 reported cases of temporomandibular joint chondrometaplasia, all of which included one or more of the following: swelling, pain, joint noise, and limited mandibular movement. These reports have described this entity as a rare lesion, but the rate of reports has increased, perhaps because of greater practitioner awareness and increased sensitivity of diagnostic tests.

Arthroscopic surgery for treatment of closed lock

This study evaluates the first 51 consecutive cases treated for limitation of mandibular movement due to closed lock. Eighty joints (22 unilateral, 29 bilateral) were treated with arthroscopic surgery. The mean follow-up was 29.4 weeks, with a range of 6 to 77 weeks. These results showed an immediate improvement after arthroscopy followed by a more gradual improvement during the next 6 months, with a plateau in improvement thereafter. All cases, unilateral and bilateral, generally reached the same level of opening.

両側性筋突起過形成６症例の筋突起位置についての頭部Ｘ線規格写真分析

Six cases of bilateral coronoid hyperplasia resulting in limitation of mandibular movement were presented. The positional interrelation between the coronoid process and the zygomatic bone and arch were examined on lateral and posterior-anterior cephalograms.The result was that in these cases the tip of the coronoid process was situated higher above the keyridge, closer to the posterior aspect of the zygomatic bone and horizontally nearer to the inner aspect of the zygomatic arch than in the controls.Cephalograms were very helpful in examining the anatomic position of the coronoid process.

Synovial chondromatosis of the temporomandibular joint: Report of a case and review of the literature

An illustrative case of synovial chondromatosis in the temporomandibular joint (TMJ) region is presented, and 36 cases reported earlier are reviewed. The present patient, a 35-year-old woman, had been suffering from swelling and pain in the TMJ area as well as limited mandibular movements for 7 years. The condition had been treated with various conservative methods without any relief of the symptoms. Finally, radiological examination revealed calcified nodules within the joint space and a surgical exploration was performed. In all, 27 loose particles were removed from the joint in connection with the extirpation of the perforated and deformed disk. The result of surgical therapy has been favourable during the follow-up period of 18 months. Although synovial chondromatosis is rare in the TMJ, it should be kept in mind as one possible disease when treating patients suffering from symptoms similar to those of mandibular dysfunction syndrome.

Symptoms of temporomandibular pain dysfunction in 400 patients: time to revise the classical profile?

The presenting symptoms of 400 patients suffering from the temporomandibular joint pain dysfunction syndrome were compared with the symptoms which they had noticed initially. The patterns of symptoms were studied for the whole group and for only those who complained of pain. It was found that for the whole group the patterns differed between the sexes, the differences being due to the influence of the symptom of clicking. No differences between the sexes were noted in the patients who complained of pain. In both groups the commonly quoted profile of clicking progressing to pain and limitation of mandibular movement was observed in the minority of patients. The relevance to aetiological theories is discussed and a case presented for more detailed clinical information in all studies of temporomandibular disorders.

How reliable is your patient? A comparison of subjective complaints and clinical findings in a group of temporomandibular joint patients

A series of patients presenting for treatment for termporomandibular joint disorders was evaluated to assess the reliability of their subjective complaints. When compared with the findings on clinical examination, discrepancies were recorded. Limitation of mandibular movement, muscle tenderness and bruxism were more frequent clinically than would have been expected from the number of complaints, whereas temporomandibular joint pain and sounds were more common subjective complaints.

A clinical study of patients with mandibular dysfunction. 1: Clinical statistics in the 1st examination

An attempt was done to evaluate clinical figures in the first examination of mandibular dysfunction patients with two or more symptoms of temporomandibular joint (TMJ) pain, TMJ sounds and limitation of mandibular movement followed by no organic change in the TMJ. The results were as follows:1. A great prevalence of female was seen and the ratio of female/male was 9 to 1.2. In age distribution, the patients of 10 years old to 19 and 20 to 29 were predominant.3. Most patients were treated by restorative therapies and few of them had experiences of several general diseases.4. Evaluating the chief complaints associated with the first symptoms, TMJ pain was much predominant in comparison with TMJ sounds.5. Clinical symptoms were expressed by TMJ pain, TMJ sounds and limitation of mandibular movement with other symptoms as headache, neck and shoulder pain and ear symptoms.6. Most patients had natural dentitions. Premature contacts were seen in centric relation in all patients and more than half of them had occlusal interferences in eccentric relations.7. The remarkable presence of oppressive pains in masticatory muscles was observed. The finding that factors which might be associated with muscle tensions were seen in many patients suggest the correlation between mandibular dysfunction and muscle hyperactivity.

A clinical study of patients with mandibular dysfunction. II. The effect of full-coverage occlusal splint therapy

The clinical effect of full coverage occlusal splint during 13 weeks insertion was investigated in 30 mandibular dysfunction patients with two or more symptoms of temporomandibular joint (TMJ) pain, TMJ sounds and limitation of mandibular movement followed by no organic change in the TMJ, who were reported in part 1 of this study.A remarkable effect of occlusal splint was obtained and 86.7% of the 30 patients were improved totally. Especially, the symptoms, TMJ pain and shoulder stiffness were much improved, but less effective was seen to buccal pain and temporal headache. The period of producing the effect of occlusal splint was different to each symptom, but no change was seen after 10 weeks in any symptoms.These results clearly show the effect of full coverage occlusal splint for mandibular dysfunction patients and useful suggestion of occlusal splint therapy to this disease was obtained.

上がく結節部に生じた骨突起と下がく骨筋突起部との間に形成された関節様構造物のため開口障害を示した１症例

Limitation of mandibular movements may be secondary to a variety of causes including trauma, partial ankylosis, developmental malformation of associated with neoplastic change. Distinction must be made between involvement of the temporomandibular joint and pathologic conditions outside the joint that limit mobility of the mandible, such as enlargement of the coronoid process and masses developing from zygomatic arch. However, elongated masses of the maxilla extending posteriorly toward the coronoid process can also affect temporomandibular joint function and should also be considered.The present report concerns. rare case of unilateral pseudoankylosis of the temporomandibular joint due to formation of joint like structure between the coronoid process and maxilla.

Reduction of mouth opening due to mandibular coronoid process enlargement

A case of unilateral mandibular coronoid enlargement associated with facial asymmetry and severe limitation of mandibular movement in a 19-year-old male patient is described. The indications for treatment and the types of surgical approach for removal of the enlarged process are discussed. The dual surgical approach required for resection of the coronoid in this case is described.

Mandibular condyle dislocation into the middle cranial fossa

A case is reported of a woman aged 25 with a dislocation of the right mandibular condyle into the middle cranial fossa. The most striking clinical feature is a strongly limited mandibular movement and the fixation of the mandible in the dislocated position. Adequate radiographic examination including tomography is necessary to obtain the proper diagnosis and to determine the position of the condyle and the displaced bony fragments of the cranial base. Early diagnosis and treatment are very important for a successful reposition. In the described patient manual reposition of the dislocated condyle was obtained 2 days after trauma. The risk of intracranial complications makes close cooperation with a neurosurgeon necessary,

Management of Myofascial Pain Dysfunction Syndrome of the Temporoniandibular Joint by Tension Control Training

• The vast majority of the so-called joint seen by clinicians involve muscle pain or tenderness, clicking, and limitation of mandibular movement, due to muscle fatigue or spasm; these painful conditions of the masticatory or cranium stabilizing muscles with alteration in mandibular function have been referred to as a myofascial pain dysfunction syndrome (MPDS) I. J', and may be described as an extracapsular disorder. It must be differentiated from intracapsular problems and therefore should not be classified as a temporomandibular joint disorder per se. The characteristic symptoms arise from the muscles of mastication, primarily the lateral pterygoids and masseters, along with the temporalis and medial pterygoids in various combinations. Although patients' complaints center around the jaw and sometimes include the ear, examination frequently discloses more extensive involvement of the musculature. Patients may exhibit tenderness to palpation of muscles in the neck, shoulders and arms, as far peripherally as the forearms.

Diagnosis and management of temporomandibular joint dysfunction syndrome

This report describes the clinical experience gained from the management of 55 patients with temporomandibular joint dysfunction syndrome, and characterized by the principal symptoms of preauricular pain accompanied by limited mandibular movements. Eighty per cent of the patients were women. Dental history indicated that their tooth loss and replacement experience and the incidence of clenching and bruxism were similar to those of a group of control patients. However, clicking in the joint was approximately twice as frequent as in the control group. No correlation was made between the incidence of temporomandibular joint symptoms and the presence of systemic disease in these groups. Half of the patients exhibited some evidence of emotional tension; of these, 15 individuals had emotional problems which were considered to be sufficiently serious to interfere with their usual daily life. Clinical examination revealed principally the presence of limited mandibular movements and tenderness of the muscles of mastication. Occlusal analysis indicated that 21 of the 55 patients required occlusal adjustment. Treatment consisted of (1) relieving painful symptoms by means of therapeutic exercises and other auxiliary methods, and (2) eliminating etiologic factors such as occlusal disharmony or emotional problems. Half of the patients were successfully treated without any occlusal adjustment. The results of this conservative approach are considered to be effective in the management of most patients with this problem.

Bilateral developmental hyperplasia of the mandibular coronoid process: A report of two cases

Summary A review of the literature indicates that only 12 cases of unilateral enlargement and three previous cases of bilateral enlargement of the coronoid process have been recorded. The clinical features, differential diagnosis, radiographic appearances, and pathology of these conditions are discussed. The importance of considering abnormality of the coronoid process as a causative factor in limitation of mandibular movement is emphasised. Methods of treatment previously employed are considered. Two case reports of bilateral enlargement are described, one of which was the subject of an operation employing an intra-oral approach. The development of the coronoid process is considered with reference to the insertion of the temporalis tendon and the conclusion is reached that unilateral enlargement generally takes the form of an exostosis or, more rarely, an osteoma or osteochondroma but that bilateral enlargement is due to developmental hyperplasia. The value of the intra-oral approach for the removal of bilateral enlargement of the coronoid process is pointed out.