[Radiation therapy for pleomorphic adenoma of the parotid]. / Adénomes pléomorphes parotidiens récidivants : place de la radiothérapie.

Parotid pleomorphic adenoma is the most frequent tumor of salivary glands. The prognosis depends on the recurrences because they could lead to iatrogenic events (facial paralysis). Moreover the risk of malignant transformation increases with the number of local relapses. This article aims at reviewing histological and radiological criteria and the surgical techniques. To improve local control, adjuvant irradiation (in first intention or after recurrence) may be useful but is still controversial for benign tumors in young patients with a risk of radio-induced cancer. We listed studies in which adjuvant radiotherapy was used so as to define its place in the treatment strategy. Prognostic factors were found by some authors. Other studies have to be done before strong evidence-based recommendations are issued.

Ascorbic acid and BSA protein in solution and films: interaction and surface morphological structure.

This paper reports on the study of the interactions between ascorbic acid (AA) and bovine serum albumin (BSA) in aqueous solution as well as in films (BSA/AA films) prepared by the layer-by-layer technique. Regarding to solution studies, a hyperchromism (in the range of ultraviolet) was found as a function of AA concentration, which suggested the formation of aggregates from AA and BSA. Binding constant, K, determined for aggregates from BSA and AA was found to be about 10(2) M(-1), which indicated low affinity of AA with BSA. For the BSA/AA films, it was also noted that the AA adsorption process and surface morphological structures depended on AA concentration. By changing the contact time between the AA and BSA, a hypochromism was revealed, which was associated to decrease of accessibility of solvent to tryptophan due to formation of aggregates. Furthermore, different morphological structures of aggregates were observed, which were attributed to the diffusion-limited aggregation. Since most of studies of interactions of drugs and proteins are performed in solution, the analysis of these processes by using films can be very valuable because this kind of system is able to employ several techniques of investigation in solid state.

Osteosarcomas of the mandible: multidisciplinary management of a rare tumor of the young adult a cooperative study of the GSF-GETO, Rare Cancer Network, GETTEC/REFCOR and SFCE.

BACKGROUND: Mandibular osteosarcomas (MOS) mostly affect young adults. Their treatment is extrapolated from that of extragnathic osteosarcomas. MATERIAL AND METHODS: A retrospective multicooperative group study was conducted to determine the impact of chemotherapy, adjuvant radiation therapy and surgery on outcomes and to identify prognostic factors. This ethical committee-approved study included a centralized review of histology slides and operative reports. RESULTS: Of 111 patients, 58.6% were male, median age 35 years (13%, ≤18 years). Histology was osteoblastic, chondroblastic, fibroblastic, conventional not otherwise specified and others in 39.6%, 30.6%, 8.1%, 12.6% and 8.0%, respectively. Pathological World Health Organisation grades were low, intermediate and high grade in 6.4%, 11.8% and 81.8%, respectively. Surgery was carried out for 94.5% of patients. Neoadjuvant chemotherapy (mixed protocols) was carried out in 93.1% of patients. Postoperative chemotherapy and radiotherapy were carried out in 54.7% and 23.8%, respectively. Median follow-up was 59.6 months (range). Five-year local control, metastasis-free, disease-free and overall survival rates were 64.6%, 68.9%, 53.2% and 69.2%, respectively. Survival was significantly associated with age, tumor size and surgery. Wide surgery with clear margins and free flap reconstruction was the strongest prognostic factor. Neoadjuvant chemotherapy improved disease-free and metastatic-free survival and increased clear margins rates from 50% to 68%. Intermediate grades behaved like high grades in terms of metastatic-free and disease-free survival. CONCLUSION: This homogeneous series is the largest to date and emphasizes the major impact of clear margins and multidisciplinary management. Neoadjuvant chemotherapy improves disease-free survival and should be recommended for both high and intermediate grade MOS.

[Revisiting the dose-effect correlations in irradiated head and neck cancer using automatic segmentation tools of the dental structures, mandible and maxilla]. / Dentalmaps : un outil pratique pour chirurgiens dentistes et radiothérapeutes pour l'estimation de la dose reçue aux dents, mandibule et maxillaire et du risque de complications postradiques en cas de soins dentaires.

PURPOSE: Manual delineation of dental structures is too time-consuming to be feasible in routine practice. Information on dose risk levels is crucial for dentists following irradiation of the head and neck to avoid postextraction osteoradionecrosis based on empirical dose-effects data established on bidimensional radiation therapy plans. MATERIAL AND METHODS: We present an automatic atlas-based segmentation framework of the dental structures, called Dentalmaps, constructed from a patient image-segmentation database. RESULTS: This framework is accurate (within 2 Gy accuracy) and relevant for the routine use. It has the potential to guide dental care in the context of new irradiation techniques. CONCLUSION: This tool provides a user-friendly interface for dentists and radiation oncologists in the context of irradiated head and neck cancer patients. It will likely improve the knowledge of dose-effect correlations for dental complications and osteoradionecrosis.

Usefulness of oral cytopathology in the diagnosis of infectious diseases.

In recent years, the incidence of oral opportunistic infections has increased, partly due to the widespread implementation of organ and bone marrow transplantation and the increase in the prevalence of human immunodeficiency virus (HIV) infection. Cytology can be used as a rapid, inexpensive and simple routine procedure in diagnosing infectious diseases of the mouth. Moreover, ancillary methods can be applied to cytological samples, increasing the specificity and sensitivity for the diagnosis of infectious diseases. This review describes the cytopathological features of the main viral, fungal, bacterial and parasitic infections of the mouth. Cytological techniques of specimen collection, identification of infectious agents by cytomorphological approaches and ancillary methods, and diagnostic pitfalls will be discussed.

[Teeth and irradiation in head and neck cancer]. / Dent et irradiation: denture et conséquences sur la denture de la radiothérapie des cancers de la tête et du cou.

Pre-irradiation dental care depends on teeth health, fields and dose of irradiation, compliance to fluorides, cessation of tobacco and psychosocial cofactors. Dental care aims at preventing complications and preserving the quality of life (eating, speech and aesthetics). Approximately 11% of patients do not require any pre-irradiation dental care. Dental complications vary from slight colorations of the teeth to major complication such as osteoradionecrosis. Osteoradionecrosis rates vary from 1 to 9%, and may be decreased by using a 21-day delay between extractions and irradiation, provided that it does not postpone cancer treatment, with a dose-dependent risk (<6% if <40 Gy; 14% between 40 et 60 Gy; > or =20% if >60 Gy). Osteoradionecrosis occurs spontaneously (35%), mostly involves the mandibula (85%).

[Enlarged marginal incision in rhinoplasty: an anatomic and clinic study]. / La voie marginale élargie en rhinoplastie: étude anatomique et clinique.

OBJECTIVE: This study is an evaluation of technical feasibility and clinical results of the wide marginal rhinoplasty. MATERIALS AND METHODS: A wide marginal approach has been used in remodeling and positioning cartilage grafts in 13 cadavers. The clinical study was focused on 20 patients with aesthetics indications and no functional need. The practise was a work on the dorsum, the tip, resections of alar and cartilage graft positioning. We investigated the feasibility of different procedures, quality of exposure and we have identified the problems and incidents of dissection. In additional a subjective evaluation of patient satisfaction and a 6 to 15 months photographic follow up were performed. RESULTS: The operative incidents and problems were similar in anatomic and clinical study. Our study found an excellent technical feasibility with an easy job in the lateral areas and more difficult in median area. CONCLUSION: Wide marginal approach in rhinoplasty doesn't substitute open rhinoplasty but can be used in specific indications.

[Contribution of the finite element method in maxillofacial surgery]. / Apport de la méthode des éléments finis en chirurgie maxillofaciale.

The finite element method is a numerical modeling tool used in various fields in medicine and surgery such as orthopedics, traumatology, and cardiovascular surgery. But this tool also has several applications in maxillofacial surgery. We present the advantages of this method by describing its principles as well as the various fields of application in maxillofacial surgery. This article was intended to help novices understand the results of various studies using this method.

[Betel quid and oral cancer: case report]. / Chique de Bétel et cancers oraux: à propos d'une observation.

Betel quid chewing is a major cause of oral cancers in Asia. Practitioners must be able to recognize premalignant lesions. Cessation of betel quid use and preventive treatment must be recommended. Primary prevention will be difficult because of the traditional nature and commercial importance of this old habit.

[The superior pedicled platysma-myocutaneous flap]. / Le lambeau myocutané de platysma à pédicule supérieur.

INTRODUCTION: The platysma-myocutaneous flap is a surgical procedure little used in oral and oropharyngeal reconstruction after malignant tumor resection. However, it provides a fast solution of reconstruction in specific indications, with functional and esthetic results comparable to other methods. ANATOMY: The platysma covers the anterolateral area of the neck and constitutes a part of the superficial musculoaponevrotic system of the head and neck. The arterial vascularization relies on the external carotid network and venous drainage on the external and anterior jugular veins. SURGICAL TECHNIQUE: The dissection of the myocutaneous-platysma flap is performed by a strict upward subplatysmal dissection. A strict subcutaneous dissection is then performed by an incision of the superior edge of the cutaneous paddle. Respecting the dissection planes as well as preservation of the facial artery, submental branch and external jugular vein improve chances of success. INDICATIONS AND CONTRA-INDICATIONS: The platysma-myocutaneous flap may help to fill defects of the oral cavity and oropharynx. The main contra-indications are prior cervical surgery and cervical radiotherapy, the presence of adenopathy requiring removal of the facial pedicle and submandibular tumor extension.

[Maxillar osteonecrosis associated with bisphosphonate treatment and dental implants]. / Ostéonécrose maxillaire sous bisphosphonates et implants dentaires.

INTRODUCTION: Bisphosphosnates are reference products used to treat osteoporosis, malignant bone disease, Paget's disease, and hypercalcemia. However these drugs seem to induce osteonecrosis of the jaws. This osteonecrosis is frequently observed and must be evoked in patients presenting with oral ulceration under bisphosphonate therapy. OBSERVATION: We report the case of a long-term fully dental implanted patient treated by bisphosphonates who presented a maxillar ostenecrosis with no previous radiotherapy. DISCUSSION: The risk factors and mechanism of this induced osteonecrosis are described. But could long term osseo-integrated dental implants be a triggering factor?

[Genic alterations in oral and head and neck squamous cell carcinomas: analysis of international literature]. / Anomalies géniques dans les carcinomes épidermoïdes des voies aérodigestives supérieures : analyse de la littérature internationale.

The development of oral and head and neck squamous cell carcinomas occurs in relation with multiple events including mainly: loss of cycle cell control, evasion from apoptosis, telomerase reactivation. Complex interactions between a set of molecules, cell cycle proteins, tumour suppressor genes, oncogenes and the telomerase, occur in the multiple step process of carcinogenesis. The 2 main ways of control of the cell cycle rely on 2 tumour suppressor genes: the P53 gene and the retinoblastoma gene or RB gene. One of the regulation pathways or the 2 regulation pathways are disabled during the development of oral and head and neck squamous cell carcinomas. Most of the time, the inactivation of the P53 pathway results from a loss of function of the p53 protein, secondary to mutation and/or deletion of the P53 gene; It may also result of the amplification of the MDM2 gene and of the inactivation of the arf protein. The RB pathway leads to cell proliferation by loss of the p16 protein, by amplification of the cyclin D1 gene and less frequently by mutation of the RB gene or loss of the retinoblastoma protein. In India and South-East Asia, the activation of RAS and MYC oncogenes appears to be related with the presence of specific carcinogens in snuff and tobacco. By blocking apoptosis, the Bcl2 protein seems to increase the resistance of tumours to radiotherapy and chemotherapy.

Polylactide acid pins versus stainless steel pins in the treatment of diaphyseal fracture: Experimental study in rats.

In order to develop a biodegradable pin for diaphyseal femoral fracture fixation, polylactide acid (PLA) pins were implanted in the femoral bone of rats. A distal diaphyseal fracture was performed. Union and tissue reaction to PLA pins versus stainless steel pins was studied after 15 days, and 1, 2 and 6 months of implantation. PLA and stainless steel pins induced the same union and a similar tissue reaction during the 6-month period. Biocompatibility of material was satisfactory.

[Complications of orthognathic surgery. Apropos of a series of 84 patients]. / Complications de la chirurgie orthognathique. A propos d'une série de 84 patients.

BACKGROUND: Patients demand satisfactory functional and esthetic results from orthognatic surgery. The aim of this study as to assess adverse outcomes after orthognatic surgery. PATIENTS AND METHODS: We retrospectively reviewed 84 patients who underwent maxillary (22.6%), mandibular (29.8%) or bimaxillary (38.1%) osteotomy in 1997. We re-examined 76 of these patients at a mean 21 months follow-up. Data were recorded for the preoperative, early postoperative, secondary postoperative and late postoperative periods. RESULTS: Infectious complications occurred in 2% of the cases of maxillary surgery. For mandibular surgery there were 10.5% infectious complications including 83% that resolved spontaneously, 3.5% neurological complications and 1.7% temporomandibular joint complications. DISCUSSION: Maxillary osteotomy has proven reliable. Major adverse outcome is infrequent but serious. Adverse outcomes in mandibular surgery are more common but less problematic.

Osteosynthesis of diaphyseal fracture by Ossatite experimental study in rat.

In order to develop a biodegradable interlocking nail for fracture fixation, hydoxylapatite pins and paste were implanted in the femoral bone of rats. A distal fracture was performed. The union and the tissue reaction to hydroxylapatite versus stainless-steel rods were studied after 15 days, 1, 2 and 6 months implantation. Metal pins induced a union. Hydroxylapatite pins (Ossatite) did not prevent callus formation, but did not lead to consolidation in all cases due to weakness of gelatin matrix binding the apatite particles together. The biocompatibility of material is satisfactory and the osteo-inductive properties of hydroxylapatite was confirmed. With injectable Ossatite , we could not obtain rat femoral fracture consolidation. We can confirm good biomaterial tolerance in bone which contrasts with important soft tissue reactions. Use of such material should be carefully limited to filling intra-osseous cavities.

Diaphyseal fractures treated by polylactide and hydroxyapatite pins. Experimental study in rat.

In order to develop a biodegradable interlocking nail for fracture fixation, polylactic acid (PLA) pins and hydoxyapatite pins were implanted in the femoral bone in rats. A distal fracture was performed. The union and the tissue reaction to PLA and hydroxyapatite versus stainless steel rods were studied after 15 days, 1, 2 and 6 months implantation. Metal and PLA pins induced a union. Hydroxyapatite pins (Ossatite) did not prevent callus formation, but did not lead to consolidation in all cases because of weakness of the gelatin matrix binding the apatite particles together. PLA and stainless steel pins induced the same union and a similar tissue reaction during the studied implantation of 6 months. The biocompatility of Ossatite is satisfactory and the osteo-inductive properties of hydroxyapatite was confirmed. With injectable Ossatite, we could not obtain rat femoral fracture consolidation. We can confirm good biomaterial tolerance in bone which contrasts with important soft tissue reactions. Use of such material should be carefully limited to filling intra-osseous cavities.