[Peripheral facial paralysis caused by an orthognathically-designed osteotomy in a Class III malocclusion]. / A propos d'une paralysie faciale périphérique secondaire à une ostéotomie à visée orthognathique dans une classe III.

Sagittal split ramus osteotomy creates an internal and an external valves. In an 18-year-old girl with class III dysmorphism, a bone spur on the internal valve compressed the facial nerve during the mandibular setback, leading to facial palsy after three days. We propose a surgical procedure and discuss short-term and long-term outcomes.

[3D cephalometry]. / Céphalométrie 3D.

The Cepha3DT software is used to generate a 3D model of the human face.

[The architectural balance of the face: a 3D cephalometric concept]. / L'équilibre architectural de la face: un concept céphalométrique 3D.

The use of the c2000 software led us to develop a new 3D cephalometric construction, based on the selection on the axial CT Scans of 8 anatomical landmarks and of teeth, all of which were situated along the trigeminal neuro matriciel facial growth axes. The analysis of this construction is based on the use of an original mathematical tool in biology: the axes of inertia. Using the selection of both mental foramen, both infra and supra orbital foramen and the head of both malleus, the C 2000 software creates a geometrical construction called: "the maxillo-facial frame", as well as, a 3D cephalometric analysis: angles, distances, areas, volumes center of gravity and axes of inertia. Using the selection of teeth, the C 2000 software calculates the axes of inertia of each tooth or of groups of teeth. The use of the axes of inertia allow us to create of a hierarchy of anatomical levels the teeth, the half arches, the arches, both arches and the maxillo-facial frame. In addition, for each of these anatomical levels, the axes of inertia create a 3D landmark which allows the calculation of the orientation of each of these elements in relation to the others. The study of 28 orthomorphic people using this analysis revealed the existence of a maxillo-facial balance that is unique for each individual.

[A new 3-dimensional cephalometry model. A new 3-dimensional parameter analysis: the axis of inertia. A new idea: maxillofacial equilibrium]. / Une nouvelle construction céphalométrique tridimensionnelle. Un nouveau paramètre d'analyse tridimensionnelle: les axes d'inertie. Un nouveau concept: l'équilibre maxillo-facial.

The authors propose a biomensurativ 3 D method based on the plotting of 8 anatomical landmarks situated on the trigeminal axis and the selection of teeth. In the analysis of this construction, we have employed mathematical tools unusual in developmental biology, the axis of inertia. The 3 D analysis allows to evidence the architectural, structural and functional balance of the dentomaxillofacial complex. This balance must be substituted to the normality concept to directly linked to cultural criterias and to the selection of mean parameters among culturally and ethnically homogeneous populations. Therapy does not have to lead to the normality of mean parameters but to the return or to the discovery of a real balance.

Densitometric evaluation of changes in the soft tissue of the chin and the lower lip during the treatment of Class III malocclusion.

The aim of this study was to use densitometry of lateral skull teleradiographs to evaluate the changes that occurred in the lower lip and chin after orthodontic or orthodontic-surgical treatment of Class III malocclusion. Forty teleradiographs from 20 patients with mandibular prognathism were made at the beginning and end of treatment. In ten of these patients the treatment was exclusively orthodontic with an edgewise appliance, and in another ten the treatment was orthodontic with a straight wire appliance combined with orthognathic and mentoplastic surgery. In the patients who were only treated orthodontically, a significant increase in density of the lower lip and the chin was found after treatment. This seemed to be related to an increase of muscular tension in these areas. Patients treated with orthognathic surgery and the straight wire appliance showed a decrease in density of the chin after treatment, but not of the lip. This can be interpreted as a consequence of muscular normalization after this procedure was accomplished.

[Surgical approach of a vertical problem: the long face syndrome]. / Approche chirurgicale d'un problème vertical: le "long face syndrome".

After a clinical review of the "long face syndrome", authors look on surgical therapies: Mandibular osteotomies often relapse because of muscular problems; maxillary surgery is preferred, associated with genioplasties , or else, with anterior and simultaneous mandibular osteotomies. They allow to obtain the desired result. Maxillary surgery has a triple advantage: a new balance for the face the upward and forward antirotation of mandible close the Open Bite the achievement of facial esthetics (alar base width, para-nasal areas and nasolabial angle). Results are shown; they would have been impossible without occlusal, surgical and orthodontic cooperation.

[Therapy of class II, division 1. Orthodontics or surgery?]. / Thérapeutique des classes II division 1. Orthodontie ou chirurgie?

Concerning five observations of class II division 1, the authors justify therapies they used. Mandibular micrognathia is excluded. Proposed schedules are all based on a precise diagnosis and knowledge of abilities and limits of orthodontics. These limits depend upon orthodontical technics and also, individual factors, particularly if patient is an adult or a child. For a child, orthodontics are preferred and, according with prediction of mandibular growth and child's cooperation, non-extraction therapies are proposed. In adult, correction of deformity ignore such helpful factors as growth and cooperation; nevertheless, it can be successfully treated by orthodontics, using differential extractions, or, if orthodontics are impossible, by orthognathic surgery. Then, surgery will include orthodontical preparation and achievement of dental arches.