[Bilateral chronic dislocation of the temporomandibular joints and Meige syndrome]. / Luxation chronique bilatérale des articulations temporo-mandibulaires et syndrome de Meige.

INTRODUCTION: Chronic dislocation of the temporo-mandibular joint (TMJ) is rare. It occurs when an acute dislocation is left untreated, in certain situations, including severe illness, neurologic or psychiatric diseases or prolonged oral intubation. CASE REPORT: A 79 years old woman, with Meige syndrome, suffered from bilateral dislocation of the TMJ for over 1 year. Surgical repositioning of the mandibular condyles and temporal bone eminectomy were performed. At the 18 postoperative months control, no recurrence has been noted. DISCUSSION: Treatment of chronic TMJ dislocations often requires a surgical procedure. Manual reduction, even under general anaesthesia, often fails because of severe muscular spasm and periarticular fibrotic changes. The management of this disorder is still controversial. We review available surgical procedures.

[Facial asymmetries and their skeletal component]. / Les asymétries faciales à composante squelettique.

The diagnosis and treatment of facial asymmetries is one of the most difficult challenges in orthognathic surgery. In some cases, the involvement of soft tissue defects or, in other cases, an associated basi-cranial asymmetry can complicate the management. The influence of various components of the cephalic end in the development of the face requires a thorough clinical and radiographic examination including the overall posture of the patient. The causes are multiple: congenital, constitutional, acquired with an important esthetic, functional, and psychological and social impact. The classification of these asymmetries can only be incomplete and purely didactic because of the multiplicity of clinical forms. Two elements are mandatory for the diagnosis and surgical treatment: first, the anterior clinical and radiological "craniofacial cross" established from the midline or midplane of the face; second, the clinical and radiological orientation of the maxillary and mandibular occlusal transverse and sagittal planes. The surgical techniques are the same as in conventional orthognathic surgery except for those used for the correction of the vertical posterior dimension of the face: condylectomy, lengthening osteotomy of the mandibular ramus, costochondral graft, and free flap. The contribution of 3D vision of the facial skeleton and its possibilities of measurement have improved the assessment of skeletal structure displacement during surgery. However, traditional radiographic examinations are still useful for pre and postoperative comparison and also to assess results. Computer simulation and computer-assisted surgery should allow achieving better and more stable results because of their reliability and easy access.

[Post-trauma mandibular osteoma]. / Ostéome mandibulaire post-traumatique.

INTRODUCTION: Osteomas are benign bone tumors with a slow progressive growth. These lesions are predominantly located in craniofacial sinuses, but other locations including mandible have been described. Their etiopathogenesis remains controversial. We report a case of post-trauma mandibular osteoma. Gardner syndrome was ruled out. OBSERVATION: A 31-year-old female patient consulted for a peri-mandibular swelling present for the previous two years. On radiological examination, a bone sclerotic lesion was observed, located on the right lower mandibular edge. Patient history documented an initial trauma at the lesion site. Surgery was performed and anatomopathological examination confirmed the diagnosis of compact osteoma. There was no recurrence one year after surgery. DISCUSSION: The etiopathogenesis of osteomas is controversial and several hypotheses are suggested. It is regarded as a true benign tumoral process, or abnormality of development, or as a reaction to trauma or infection. The development of osteoma after trauma has been described in several cases, notably in mandibular locations exposed to shocks (angle and lower edge). Multiple osteomas must mandatorily lead to screening for a Gardner's syndrome, because of the associated risk of colon cancer.

[Asymmetric hypertrophy of the masticatory muscles]. / Hypertrophie asymétrique des muscles masticateurs.

INTRODUCTION: Hypertrophy of the masticatory muscles most commonly affects the masseter. Less common cases of isolated or associated temporalis hypertrophy are also reported. Parafunctional habits, and more precisely bruxism, can favor the onset of the hypertrophy. This condition is generally idiopathic and can require both medical and/or surgical management. OBSERVATION: A 29-year-old patient was referred to our department for an asymmetric swelling of the masticatory muscles. Physical examination revealed a bilateral hypertrophy of the masticatory muscles, predominantly affecting the right temporalis and the left masseter. Major bruxism was assessed by premature dental wearing. The additional examinations confirmed the isolated muscle hypertrophy. Benign asymmetric hypertrophy of the masticatory muscles promoted by bruxism was diagnosed. Treatment with injections of type A botulinum toxin was conducted in association with a splint and relaxation. Its effectiveness has been observed at six months. DISCUSSION: Few cases of unilateral or bilateral temporalis hypertrophy have been reported, added to the more common isolated masseter muscles hypertrophy. The diagnosis requires to rule out secondary hypertrophies and tumors using Magnetic Resonance Imaging. The condition is thought to be favoured by parafunctional habits such as bruxism. The conservative treatment consists in reducing the volume of the masticatory muscles using intramuscular injections of type A botulinum toxin. Other potential conservative treatments are wearing splints and muscle relaxant drugs. Surgical procedures aiming to reduce the muscle volume and/or the bone volume (mandibular gonioplasty) can be proposed.