[Ewing's sarcoma of the jaw. The value of multidisciplinary management. Apropos of 4 cases]. / Sarcome d'Ewing des maxillaires. Intérêt d'une prise en charge multidisciplinaire. A propos de 4 cas.

Ewing's sarcoma is the second most common malignant bone tumor of childhood, yet it is a rare tumor. Primary maxillary localization is unusual and occur in only 1-2% of cases, mostly in the mandible. The prognosis of Ewing's sarcoma has been improving considerably since the introduction of combined modality treatment. The estimated overall survival at 4 years is 75%. It is widely accepted that prompt chemotherapy is necessary to treat occult micrometastasis, present in over 80% of cases at time of diagnosis, and to reduce the tumor size. Prognostic factors correlated with a poor overall survival are large tumor size and poor histologic response to initial chemotherapy. Adequate local control of Ewing's sarcoma can be achieved after chemotherapy, with radical or conservative surgery and radiotherapy. Surgery was recommended whenever possible. Radiation dosage and fields are based upon the quality of surgery and histological response to chemotherapy. Concern has been raised, however, regarding deleterious late effects of radiation in this young population. Conservative surgery and reconstruction are often used to improve functional outcome. We report four cases of Ewing's sarcoma localized to jaw bone and mandible, successfully treated by combined modality treatment.

[Severe diffuse facial cellulitis]. / Les cellulites faciales graves diffuses.

Twenty cases of severe cervicofacial infections among 184 cases of cellulites treated in 1991 and 1992 at the Lille University Hospital were investigated. Outcome was compared with results reported in the literature. Outcomes were similar and emphasized the critical nature of this type of infection which caused 7 deaths in our series and severe anatomic and functional sequelae. All patients (n = 20) were given anti-inflammatory drugs prior to surgery. The correlation between disease severity and use of anti-inflammatory drugs would appear to be an established fact. Criteria predicting severity were identified in order to obtain a score for high or low risk and to better adapt the medical and surgical management strategy.

[Mandibular mechanics in temporomandibular joint pain-dysfunction syndrome]. / La mécanique mandibulaire dans le SADAM.

There are several reasons for perturbed mandibular mechanics in SADAM: craniofacial architecture anomalies, malocclusions, lingual dyspraxia, postural disorders. SADAM diagnosis and therapeutics should be conducted by a pluridisciplinary team.

[Intravenous sedation in implantology]. / Sédation intraveineuse en implantologie.

Local or block anesthesia can be used satisfactorily in many implant procedures. However, when advanced implant techniques or pre-prosthetic reconstruction surgery of the maxillofacial bones are required, local or regional anesthesia is insufficient. The "day-hospital" concept is a rational approach which meets the requirements for anesthesia and deep sedation with criteria for patient safety and comfort while guaranteeing optimal operating conditions. Intravenous sedation, both "conscious" and "deep" sedation, is a very well adapted form of anesthesia for implant recipients. Local or block anesthesia is enhanced or reinforced prior to surgery by the intravenous administration of a sedative and anxiolytic agent (single-drug concept), such as a benzodiazepine, associated or not with a morphinomimetic agent and an antihistaminic substance (multiple-drug concept). The main goal is to maintain spontaneous respiration while obtaining postoperative amnesia of the entire procedure. Mandatory use of a pulse oximeter has greatly contributed to improved safety of intravenous sedation, essentially indicated for operations not lasting more than 2 and a half hours in patients in good general health (scoring 1 or 2 in the American Society of Anesthesiology (ASA) classification) and with a low risk of postoperative complications. This concept requires an adapted technical facility. The operating theatre should have all the equipment necessary for cardiovascular, neurological and respiratory emergency care. The postoperative recovery room should also be equipped with cardiovascular monitoring devices and be able to accommodate an intensive care unit. Under these strict rules, short duration surgical procedures (< 150') can be performed : 1) with the best conditions of medical safety, 2) with improved operating conditions for the implant surgeon (the patient responds immediately to vocal orders when necessary) while asepsis is maintained as easily as with general anesthesia, 3) with better conditions for postoperative care and patient comfort (the anesthetist is continuously present). 4) better psychological conditions for the patient who will be discharged the same day, 5) with total amnesia of the entire surgical procedure, 6) elimination of a usually disproportionately long hospitalization. Day hospitalization also helps contain health care costs by cutting out the need for overnight care and accommodation. We underline the safety of current intravenous sedation techniques and present two series of data related to the use of this technique by an anesthetist and an operating surgeon in a day hospital from 1986 to 1995.

[Immature teratoma of the mandible with ameloblastic component]. / Tératome immature de la mandibule à composante améloblastique.

A case of immature teratoma involving mandible in a 56 year old woman is reported. This teratoma is composed of ameloblastoma structures mixed with some usual components of teratoma: osseous and cartilaginous foetal tissue, indifferenciated blastema, neuroblastic structures, acinous glands and melanotic cells. A lymph node is involved by metastatic mature glial tissue. This patient is treated by pelvimandibulectomy and irradiation. Histogenesis of this teratoma unusual by this ameloblastic component and this mandibular localization is reviewed.

Craniofacial behavior of sutures in young rabbits postimmobilization.

Although sutures have been identified as being important growth sites of the craniofacial complex, some points are still debated. The aim of our work was to analyze coronal suture response after immobilization in 24 New Zealand White rabbits. This immobilization was induced by an adhesive that bridged the coronal suture under investigation. Contrary to the reports of several authors, our procedure did not promote craniostenosis. The sutural space remains present even if it appears considerably reduced. Our cytometric examination clearly demonstrates that growth reduction localized on the external cortex of the calvaria whereas the internal cortex have a subnormal evolution. These findings favor a different evolving profile of both tables of the calvaria. They also suggest that one should be very careful before considering this procedure, as it may induce craniostenosis.

[Intra-masseter metastasis of a gastric adenocarcinoma]. / Métastase intra-massétérine d'un adénocarcinome gastrique.

We report a case of metastasis in the masseter muscle secondary to stomach carcinoma. Second neoplastic invasion in skeletal muscle is an exceptional phenomenon. And this frequency is paradoxical against corporeal muscular mass. Immune hypothesis is conjure up for explain this fact. Symptoms are not specific and the diagnosis is not often recognized. However, systematic postmortem investigation is positive in one per cent of the cases. Consequently, every painful and nodular induration involved in carcinoma supervision must do perform a systematic biopsy.

[Closure of anterior oro-nasal communications, sequelae of cleft palate, using a retro-incisal flap]. / Fermeture des communications bucco-nasales antérieures, séquellaires de fente palatine, par lambeau rétro-incisif.

The persistence of a residual communication between mouth and nose, is an important sequela a after primary closing of cleft palate. This retrospective study reports twenty-one cases of a new technique (retro-incisive flap) used for closing this residual communication. This flap is an easy and reliable method with an 85% success rate, so we recommend it as the first choice in this indication.

[Orthognathic surgery of the atrophic upper jaw. A proposal for a single-stage treatment. Le Fort I osteotomy with bone grafts and implants]. / Chirurgie orthognathique du maxillaire supérieur atrophique. Une proposition de traitement en un temps. L'ostéotomie de Lefort I avec greffe osseuse et implants.

We report an osteotomy technique for the maxilla using an iliac graft and simultaneous implantation for correction of atrophic class III dysmorphosis of the maxilla. The advantages and disadvantages of this technique are discussed on the bases of a 3-year experience.

[Facial volume and its global position in vestibular orientation, in adults and during growth]. / Volume facial et sa position globale en orientation vestibulaire, chez l'adulte et durant la croissance.

Two sagittal surfaces were defined on the dry skull of 96 youngs and 51 adults Caucasian subjects in vestibular orientation. The surface of the face and the surface of the "total face" (by including the buccodental and mandibular surfaces) were measured with a planimeter. From the longest maxillary and zygomatic distances, the volume of two ellipsoids were calculated. The radius of a sphere corresponding to this volume was then deducted. Each sphere was then positioned taking the vestibular coordinates, corresponding to the barycenter of the sagittal surface, as the center. The ontogenetic evolution of these two points showed a curve similar to that of all the points in the splanchnocranium of man. Quantitative results are given for volumes and calculated data. The two facial spheres were then positioned relative to two known spheres in the neurocranium. The quadrilaterals drawn between the 4 centers denote a phylogenic constancy of the directions when compared with the results observed in man and those obtained in anthropoïds.

[The morphogenesis of the temporomandibular joint considered in its phylogenic aspects in vestibular orientation]. / La morphogenèse de l'articulation temporo-mandibulaire considérée sous son aspect phylogénique en orientation vestibulaire.

Comparative phylogenic movements of skull points can be obtained using vestibular orientation and skulls from various mammals after reducing the bimediocondyle distance to approximately 100 mm (as in man). With this method, the condyle is seen to move backwardly and rise in a very thin bony area which will be covered by the increasing volume of the encephalus. A "mandibulocerebral" index of less than 100 is a criteria of humanoid species. A part posterior to the fixed zone in primate which will become the temporal condyl in man is eroded by the mandibular condyle. The tympanum migrates upwardly and posteriorly in primates and turns forwardly in man, contributing to limit the glenoid cavity posteriorly. The anterior limit to mandibular propulsion in primates is the intercanine bite; this disappears in man as does the post-glenoid apophysis which is reduced to a tubercle with no limiting effect. In man, function of the temporomandibular joint depends on its more delicate construction than in primates. The major humanoidizing processes alone, i.e. posterior movement of the jaws and their reduced volume, bipedism, and amplification of the cerebral volume, are sufficient to explain this situation which results from the effect of phylogenic evolution.

[A panorama of current materials for osseous application in maxillofacial surgery and oral implantology]. / Panorama des matériaux actuels pour apport osseux en chirurgie maxillo-faciale et implantologie orale.

Many materials are used in bone reconstruction. According to their physico-chemical structure, their activity is based on one of the three main mechanisms of bone repair: osteogenesis, osteoconduction, osteo-induction. The materials can be classified in two categories: tissues and substitution biomaterials. Tissues may be living ones (mainly, autograft) or non living ones (mainly, allograft or xenograft). Among the substitution biomaterials, we find synthetic materials (calcium based ceramics, vitreous ceramics and bioglasses, polymers) and composite materials made of a mixture of synthetic and natural materials or a mixture of different synthetic materials or a mixture of different synthetic materials. At last, membranes provide a new technic in bone reconstruction. They come from natural origin (human or animal) or synthetic origin (resorbable or non resorbable).

[Risks and regulations related to materials used in implantology and maxillofacial surgery]. / Risques et réglementations relatifs aux matériaux utilisés en implantologie et chirurgie maxillo-faciale.

In the present paper, the authors call in mind the definitions of biocompatibility and the essential qualities required for biomaterials. The materials mostly used in implantology and maxillofacial surgery are numerous alloys, bioceramics, resorbable and non-resorbable polymers, and finally osseous substitutes of human or animal origin. As to synthetic and non-living materials, the risks in patients are generated by the degradation products. These may induce tissular reactions of inflammatory or immune origin owing to toxic effects. Concerning osseous substitutes, rejections are mostly of immune origin, for allografts and in particular for xenografts. Infections may be another major risk and in spite of all precautionary measures viral infections by hepatitis B, HIV and transmissible spongiform encephalopathy are not yet got under total control. It is just in these domains that one can state juristic lacks which national and european organisation of standardisation and homologation have to cover during the next few years.