Bilateral sagittal split osteotomy training on mandibular 3-dimensional printed models for maxillofacial surgical residents.

Complications with bilateral sagittal split osteotomy (BSSO) can sometimes result from surgical inexperience. Our aim was to present a 3-dimensional printed mandibular model for BSSO training in a maxillofacial surgical education programme. A polymethacrylate mandibular model obtained from mandibular cone-beam computed tomographic (CT) images was designed and printed for use in training. Twenty-four residents were each asked to do a BSSO according to the Epker/Dal-Pont technique. The session was conducted as a simulation course with a final debriefing. A questionnaire before and after the test was filled in using a 10-point Likert scale to assess the participants' knowledge. The mandibular model provided a realistic way of handling the trabecular bone after cortical osteotomy, as well as in the splitting phase. Significant increases in knowledge and surgical skills were noted for all steps of the BSSO, particularly regarding the use of the piezoelectric device for osteotomy, and for management of wisdom teeth in the splitting zone (3.00 ±2.16 to 6.95 ±2.06 and 2.73 ±1.91 to 5.75 ±2.63, respectively; p1=0.0002 and p2=0.0003). We think that this is a valuable printed mandibular model for the development of surgical skills for BSSO in maxillofacial surgical residents.

Vertical lengthening genioplasty: A new osteotomy technique.

Vertical insufficiency of the chin imbalances the orofacial and aesthetic parameters of the lower third of the face. We here propose a new osteotomy technique for chin lengthening. Our procedure is based on a single osteotomy and it does not require any interposition of a bone graft. In our experience with seven patients, we report good aesthetic and morphometric outcomes at one year.

Associated relaps factors in Le Fort I osteotomy. A retrospective study of 54 cases.

PURPOSE: The Le Fort I osteotomy (LFI) procedure is commonly used to restore morpho-functional balance. The goal of maxillofacial surgeons with this procedure is to achieve occlusal stability. To identify factors associated with relapse after maxillary advancement in cleft lip and palate patients, the one-year post-operative stability of Le Fort I osteotomy was evaluated. METHODS: Horizontal and vertical relapse were analysed on lateral cephalograms by retrospectively using tracing paper in an orthonormal landmark in 54 patients undergoing unilateral cleft lip and palate surgery who were monitored at Nantes University Hospital. The lateral cephalograms were performed pre-operatively, immediately post-operatively, and after one year. Several variables were studied such as population data, intra-operative and post-operative surgical treatment, and surgical movement. RESULTS: At point A, the subspinale point, the mean advancement during surgery was 4.2 mm, with a relapse of 0.8 mm (20.1%). The mean downward movement was 2.0 mm in 26 patients who had a clockwise rotation of the maxilla, with a relapse of 0.6 mm (28.4%). The mean upward movement was 2.3 mm in 27 patients who had a counterclockwise rotation, with a deterioration of 0.2 mm (7%). A 7-millimetre surgical advancement corresponded to the threshold value beyond which relapse appeared to be significantly greater but still less than two millimetres in 75% of cases. CONCLUSION: The degree of advancement appears to be the only variable correlated with the amplitude of the relapse.

Surgical correction of mandibular hypoplasia in hemifacial microsomia: A retrospective study in 39 patients.

PURPOSE: Repair of the mandibular deformity in hemifacial microsomia (HFM) remains controversial, and there is scant information in the literature regarding the late outcomes. The aim of this study was to evaluate architectural and aesthetic long-term outcomes for primary mandibular surgery in patients with HFM. MATERIALS AND METHODS: Thirty-nine patients with types II and type III HFM were included in this retrospective study. Depending on the nature of the mandibular deformity, patients were treated using a costochondral graft (CCG) or a vertical ramus osteotomy (VRO). Architectural and aesthetic parameters were evaluated preoperatively, postoperatively, and at the end of the follow-up period. RESULTS: The architectural analysis revealed the restoration of a level occlusal canting at the end of the follow-up period (p < 0.0001); the chin deviation was corrected immediately by the surgery, although a trend to recurrence was noted at the last follow-up evaluation (p < 0.0001). The aesthetic assessment revealed a significant improvement of the chin deflection, and correction of the lip commissural line tilt (p < 0.0001). Twenty-three percent of the patients required an additional orthognathic revision. CONCLUSION: CCG and VRO continue to be suitable and safe procedures with good outcomes that allow a single-stage correction of occlusion and preservation of mandibular growth in young patients with type II and type III HFM.

Vertical ramus elongation and mandibular advancement by endobuccal approach: Presentation of a new osteotomy technique.

INTRODUCTION: Several surgical procedures have been proposed for the treatment of hyperdivergent dentoskeletal deformities. We propose a new osteotomy technique allowing for lengthening and advancement of the mandibular ramus by intra-oral approach. SURGICAL PROCEDURE: This technique differs from the conventional sagittal split osteotomyin that which the anterior osteotomy line is not continued until the basilar edge but stopped 5-6mm above it. Cutting of the pterygomasseteric sling is systematically done allowing for the lowering of the mandibular angle. Osteosynthesis is performed by transjugal and intra-oral approaches, using two adjustable miniplates. Our supra-angular technique allows for both elongation of the ramus and advancement of the mandible. Unlike the vertical ramus osteotomy proposed by Caldwell-Letterman, external incision and intraoperative cervical hyperextension are not required.

[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.

[Stability of Le Fort I impaction osteotomies]. / Stabilité osseuse des ostéotomies de Le Fort I d'impaction.

INTRODUCTION: Long-term results of Le Fort I osteotomy with vertical impaction for maxillary vertical excess may be not stable. We had for aim to analyze postoperative maxillary and dental displacement after a Le Fort I vertical impaction osteotomy, to identify causes of relapse. PATIENTS AND METHODS: A clinical and radiological evaluation was made on postoperative occlusion (early and late). The position of three bone (O: lower orbit; P: greatest palatine convexity; T: lowest part of the mandibular foramen) and of three dental landmarks (I: occlusal edge of the upper incisor; i: occlusal edge of the lower incisor; m: first molar distal vestibular cuspid) was measured in a standardized method on pre-surgical, early and late (1 to 2.5 years) postoperative cephalometric X rays. Eighteen patients were operated by the same surgeon for maxillary anterior vertical excess and underwent Le Fort I impaction osteotomy, alone or associated with a mandibular osteotomy. Stability was defined by a postoperatory displacement smaller than 1mm. RESULTS: All patients had stable bone landmarks. Three patients had unstable dental landmarks due to relapse. DISCUSSION: Impaction maxillary osteotomy provides stable bone results for maxillary facial height excess. Unsatisfactory outcome is always due to postoperative dental and alveolar displacement. These results correlate to published data.

[Cephalometric study of the velocardiofacial syndrome: Impact of dysmorphosis on phonation]. / Céphalométrie du syndrome vélocardiofacial: les conséquences phonatoires de la dysmorphose.

INTRODUCTION: Velopharyngeal insufficiency is a frequent sign of the velocardiofacial syndrome (VCFS) but its origins are not well-documented. Our aim was to establish a correlation between this functional disorder and regional morphological anomalies. PATIENTS AND METHODS: Twenty-seven of 36 patients presenting with VCFS could be included retrospectively. We measured cavum depth and velum length on lateral orthodontic X-rays, and assessed the relationship between these two measures. We compared these measures to those of reference populations. Postoperative phonation was assessed with an aerophonoscope. RESULTS: The patients presented with a short velum and a deep cavum. Cranium base and upper cervical spine were malformed in 22 of the 27 patients. Seventeen of the 23 assessed patients (66%) improved their phonation after surgery. DISCUSSION: Our data suggests that velopharyngeal insufficiency in VCFS could be the result of a more global craniospinal growth disorder the functional consequences of which remain unclear. The frequent association of morphological anomalies with mental retardation is probably responsible for the failure to normalize phonation.

[Acute presentation in oral schwannoma]. / Présentation aiguë d'un schwannome intraoral.

OBSERVATION: We report an unusual presentation of an acute septic maxillary vestibular schwannoma in a 19-year-old female patient. The anatomopathological examination of the tumor showed Schwann cell proliferation and ulceration of infectious origin. DISCUSSION: Intraoral schwannomas are uncommon. They generally induce local pain on percussion and dysesthesia. Isolated intraoral schwannomas are very rarely linked with type I neurofibromatosis. They do not require any specific follow-up after exeresis.

[Intracoronary brachytherapy: a meta-analysis]. / Curiethérapie endocoronaire: une méta-analyse.

Intracoronary brachytherapy aims at a reduction of in-stent restenosis by lessening neo-intimal proliferation. To assess its clinical potential, a systematic review of the literature indexed in the standard biomedical bibliographic databases selected eight prospective randomized clinical trials; seven of them, comparing coronary brachytherapy and non-treatment or placebo, have been included in the present meta-analysis. This analysis confirms the angiographic benefit of this procedure, as reported in the individual studies; it also shows, however an excess of clinical adverse effects not exhibited by any individual trial. Therefore, intracoronary brachytherapy cannot be recommended as routine practice, while one cannot rule out its interest in special situations.

[Very large mandibular keratocysts: review]. / Très grands kératokystes mandibulaires: mise au point.

The odontogenic keratocyst (OKC) is unique among odontogenic cysts of the jaws, especially because of the high risk of recurrence. Epidemiological studies demonstrate male predominance and the most common location in the mandible. We reviewed our own experience with eight patients and data in the literature, focusing on very large mandibular keratocysts. We reviewed the clinical, radiological, and histological elements required for the positive and differential diagnosis. CT scans should be performed for very large cysts due to their superiority over plain x-rays, both for treatment planning and follow-up. Surgical treatment is indicated. The choice remains controversial between radical and conservative approach. We prefer conservative treatment. Problems concerning bone healing, recurrence and follow-up are also discussed.

[Investment and operating costs of the electron beam scanner at the Broussais Hospital]. / Investissement et coût d'exploitation du scanographe à faisceau d'électrons de l'hôpital Broussais.

Cost of Imatron and of its building was 150,000,000 FF in 1989, highly more expensive than for other CT. Cost of "maintainance" is only 9.5% of its acquisition price against 21% for other CT. The replacement of high power and detectors is less frequent in Imatron than X ray tubes in the other CT. Imatron was often out of order during the 2 first years because of high power. Now the time devoted to break down is only 2.5%. A slice price is 4.75 FF for Imatron and the mean slice price is 7.38 FF for the other Assistance Publique CT (from 4.88 to 10.53).