[Ameloblastoma of the jaws. A retrospective analysis from 1994 to 2007]. / Améloblastomes des mâchoires. Analyse rétrospective de 1994 à 2007.

INTRODUCTION: Ameloblastomas and keratocysts are the most frequent epithelial odontogenic tumors of the jaws. They have a high recurrence rate. This retrospective study reviews the features of ameloblastomas operated on in our unit from 1994 to 2007. PATIENTS AND METHODS: The studied parameters were sex, ethnic origin, age at diagnosis, clinical signs, radiographic presentation, site distribution, histological type, treatment, and follow-up records. RESULTS: One hundred and sixteen patients were included (with 239 surgical samples). The mean age was 36 years, with a majority of Europeans, 60% of multilocular radiolucent lesions with root resorption, mandibular location (93%). Twenty-one percent of the patients presented with an impacted tooth, the third molar in 79% of cases. Fifty percent of the lesions were from 5 to 13cm in length, 10% longer than 13cm. The most common histological type was follicular ameloblastoma. Patients were treated by enucleation in 82% of cases and radical mandibular resection with reconstruction in 11% of cases. The follow-up was documented for 96% of the patients with a 44% recurrence rate. Seventy-four percent of patients with a double recurrence presented with a "follicular" ameloblastoma. DISCUSSION: We prefer a well-performed enucleation which preserves surrounding bone. The high rate of follicular type recurrence should more systematically lead to a combined treatment: periostectomy and tooth extraction. Our data was compared with previously published large series.

Unicystic ameloblastoma of the maxillary sinus: Pitfalls of diagnosis and management.

BACKGROUND: Ameloblastoma is a common odontogenic tumor of the jaws that comprises 3 variants: conventional (solid), unicystic and peripheral ameloblastomas. Unicystic ameloblastoma (UA) in the maxillary sinus is very rare. With a secondary infection, the clinical features may lead to incorrect diagnosis and treatment. PATIENTS AND METHODS: A 19-year-old man was referred for the management of sinusitis and a mass at the right cheek. A few weeks earlier, the patient presented with acute cellulitis at the same area and underwent an incision and drainage in a primary care unit without any appropriate investigation. A radiographic examination revealed a massive lesion in the right maxillary sinus. An unerupted tooth within the lesion was found at the level of the orbital floor. RESULTS: The patient was successfully treated by enucleation of the tumor and curettage. The specimen was sent for histopathological examination, and the definite diagnosis was UA. The patient has been followed-up periodically for 5 years without recurrence. DISCUSSION: This case report suggests that primary care doctors should pay attention to differential diagnosis of orofacial lesions. It is therefore of great benefit to organize continuing education for general physicians who initially meet oral disease patients as a 'gate keeper'. Errors of clinical diagnosis and management of orofacial lesions would be minimized. Pitfalls of diagnosis and management of UA in the maxillary sinus were briefly reviewed.

Isolation of alkane-degrading bacteria from deep-sea Mediterranean sediments.

AIMS: To isolate and identify alkane-degrading bacteria from deep-sea superficial sediments sampled at a north-western Mediterranean station. METHODS AND RESULTS: Sediments from the water/sediment interface at a 2400 m depth were sampled with a multicorer at the ANTARES site off the French Mediterranean coast and were promptly enriched with Maya crude oil as the sole source of carbon and energy. Alkane-degrading bacteria belonging to the genera Alcanivorax, Pseudomonas, Marinobacter, Rhodococcus and Clavibacter-like were isolated, indicating that the same groups were potentially involved in hydrocarbon biodegradation in deep sea as in coastal waters. CONCLUSIONS: These results confirm that members of Alcanivorax are important obligate alkane degraders in deep-sea environments and coexist with other degrading bacteria inhabiting the deep-subsurface sediment of the Mediterranean. SIGNIFICANCE AND IMPACT OF THE STUDY: The results suggest that the isolates obtained have potential applications in bioremediation strategies in deep-sea environments and highlight the need to identify specific piezophilic hydrocarbon-degrading bacteria (HCB) from these environments.

Evaluation of colonisation of peripheral venous catheters inserted by prehospital emergency service teams (SMUR) in France.

There are no data in the literature on colonisation of peripheral venous catheters (PVCs) inserted by French prehospital emergency and resuscitation service teams (SMUR). In a descriptive and prospective study we evaluated colonisation of PVCs inserted and managed solely by a SMUR team. A total of 171 PVCs were analysed. Bacteriological results were positive for seven catheters (4.09%/threshold=10(2)cfu/mL). Our analyses of the characteristics of patients and interventions show a significantly higher number of elderly patients among those colonised (P=0.02) with less satisfactory venous access (P=0.006) and smaller catheter bores (P=0.009). No differences were seen regarding the other evaluation criteria: gender, aetiology, site of intervention, number and site of venepuncture procedures, blood pressure and duration of catheterisation. The absolute value of colonisation seen in our study appears consistent with those reported in the literature, but no comparisons are possible due to widely divergent catheterisation times between published work (days) and our own data (minutes). Our results suggest a reassessment of current recommendations of routine changeover of these catheters, with the attendant discomfort for patients and cost in terms of time and money. We recommend a randomised study comparing catheter colonisation levels associated with routine catheter replacement with targeted replacement based on risk factors.

[How to avoid research misconduct - recommendations for surgeons]. / Comment éviter la non-conformité de la recherche biomédicale? Recommandations aux chirurgiens.

Research misconduct is defined by the Royal College of Physicians of Edinburgh as any behaviour by a researcher, whether intentional or not, that fails to scrupulously respect high scientific and ethical standards. Various types of research misconduct include fabrication or falsification of data, plagiarism, problematic data presentation or analysis, failure to obtain ethical approval by a research ethics committee or to obtain the subject's informed consent, inappropriate claims of authorship, duplicated publication, and undisclosed conflicts of interest. These can result in patient injury, deterioration of the patient-physician relationship, loss of public trust in biomedical research, as well as pollution/degradation of the medical literature. Surgical research malfeasance has been underreported, and no practical guidelines for good research and publication have appeared to date in French surgical journals. In an attempt to uphold the scientific integrity of our profession, we discuss research misconduct and emphasise preventive measures and considerations for surgeons.

[Osteoradionecrosis and dental implants]. / Ostéoradionécrose sur implants dentaires.

INTRODUCTION: Osteoradionecrosis (ORN) is a severe complication of radiation therapy (RT). A triggering factor is frequently present. It is often a dental, periodental, or surgical traumatism. We report the case of a bilateral ORN: the first lesion appeared 3months after the end of RT around the osteosynthesis plate and was treated by mandibular resection. The second lesion appeared 40months after RT on the opposite side, due to peri-implantitis. Dental implants had been inserted 10years before cancer therapy. No case of ORN in post-implantation RT had been previously reported. CASE REPORT: A 75-year-old woman was admitted for a squamous cell carcinoma of the right cheek extending to the intermaxillary commissure, the maxillary tuberosity, the soft palate, the lingual junction, and the vestibule up to the second premolar area. There was no suspicious lymph node. She had undergone dental implant procedure 15 and 10 years before, respectively, one in the second premolar position of the right maxilla and four in the premolar and molar left mandible area. All of them were osseo-integrated and charged. A trans-mandibular buccopharyngectomy with modified radical neck dissection was performed, completed by RT. The total dose of irradiation was 65Gy in the oral cavity and 45Gy on cervical and supraclavicular areas. Delayed mucosal healing was observed on the right mandible and ORN appeared in this area 3months after the end of irradiation. Mandibular resection was necessary. Later, the right maxillary implant was lost, and multiple dental extractions were required. Forty months after RT, peri-implantitis was observed on the left side of the mandible, complicated by ORN and pathological fracture. No surgical reconstruction could be performed because of the patient's age and state. The patient was carrying a complete removable maxillary prosthesis on latest follow-up. DISCUSSION: This was the first case of ORN on dental implants placed before RT. RT is a risk factor of implant failure, a relatively rare and unpredictable event. Most often, it causes implant loss and exceptionally ORN. In our case, ORN was bilateral. The first lesion was probably due to surgical trauma. The second one, on the opposite side, was caused by peri-implantitis. Irradiation overdose on the alveolar mandibular ridge, close to the implant, may have been the cause. In our case, there was no severe pain, and slow evolution led to a pathological fracture.

Management of osteoradionecrosis of the jaws: an analysis of evidence.

AIM: To review and discuss the management of jaw bone osteoradionecrosis (JORN) based on levels of evidence. METHODS: The Medline/PUBMED and Cochrane search was performed to identify all studies on the management of JORN, published in English, French, and German during January 1975-October 2007. Only clinical researches were identified and classified into four levels of evidence before being examined. All references of the retrieved articles were analysed. FINDINGS: Seventy three articles and their additional 45 citations were evaluated. Most of the eligible literature provided observational evidence. Hyperbaric oxygen therapy (HBOT) is an adjunct; however, its clinical usefulness remains controversial. A conservative approach should be limited to early-onset JORN, while radical surgery is indicated for an advanced or refractory lesion. Free tissue transfer is the reconstruction of choice for large defects without the need of HBOT. Some new technologies have also been studied, including ultrasound, biological molecules, distraction osteogenesis and antioxidant agents. CONCLUSIONS: Most of the reports on the treatment of JORN offer weak evidence. Current information seems insufficient for establishing the definite treatment guideline; thus, well-designed studies with long-term clinical data are encouraged.

Laparoscopic resorbable mesh fixation. Assessment of an innovative disposable instrument delivering resorbable fixation devices: I-Clip(TM). Final results of a prospective multicentre clinical trial.

BACKGROUND: The aim of this study was to assess the performance and tolerance of an innovative disposable instrument delivering resorbable clips (I-Clip, Sofradim, France) intended for mesh fixation in inguinal, incisional and umbilical hernias of the abdominal wall. The fixation device was designed to be resorbable in 1 year, with reduced trauma to the underlying tissues or the mesh, and with initial mechanical properties equivalent to those of conventional metal staples. METHODS: The study involved 105 patients with inguinal, umbilical or incisional hernias enrolled from 11 centres. Inguinal totally extra peritoneal (TEP) or trans abdomino pre-peritoneal (TAPP) repair was performed with Parietex mesh, incisional or umbilical hernias were treated via the intraperitoneal route with Parietex composite. I-Clips were used for mesh fixation in both indications according to the surgeon's habits. Efficacy was the principal assessment criteria evaluated by two parameters: quality of fixation evaluated subjectively at the time of procedure and recurrence rate according to the follow up at 1, 6 and 12 months. Pain evaluated by the patients using a visual analogue scale (VAS) was the principal secondary assessment criteria. Other tolerance criteria were also evaluated during surgery and follow up. RESULTS: The surgeons' evaluation of the fixation quality was assessed as good to very good in 100% of ventral hernias and good to very good in 85-92% of inguinal hernias. At 1 month, 90% of patients (94/104) were totally pain-free (VAS score: 0) and only ten patients reported low pain (VAS scores: 0.3-3.1). At 1 year, the pain described by those ten patients finally disappeared, 98% of patients (102/104) were totally pain-free. The rate of minor complications not related to the device concerned 5% of the patients at 1 month, which was reduced to 2% at one year and no recurrence or mesh sepsis was observed. CONCLUSIONS: The ease of use of this device, combined with the absence of recurrence related to the investigated device and the good pain-free outcome in this group of patients confirmed the effectiveness and tolerance of the resorbable fixation concept of I-Clip(TM).

[Mandibular fractures: epidemiology, therapeutic management, and complications in a series of 563 cases]. / Fractures de la mandibule: épidémiologie, prise en charge thérapeutique et complications d'une série de 563 cas.

INTRODUCTION: The Paris urban and suburban area (Ile-de-France) has the leading regional population in France. This population has specific characteristics. This study concerns mandibular fractures. MATERIAL AND METHOD: A retrospective epidemiologic, clinical, radiographical and therapeutic analysis is conducted with a series of 563 patients with mandibular fracture treated at the Pitié-Salpêtrière University Hospital, in Paris, from 1998 to 2000. RESULTS: Mandibular fracture was generally observed in young men, 40% of whom had poor oral hygiene. The brawls were the dominant etiology (57%) followed by road accidents (12%). The most frequent unifocal fractures were condylar fractures (32%) and angle fractures (32%). The most frequent bifocal mandibular fracture associated angle and symphysis fractures (32%). Osteosynthesis was performed for 73% of patients, including 30% with associated maxillary locking. Complications occurred in 4.8% of the studied cases. DISCUSSION: Despite the increase in traffic, the incidence of road injuries has declined. The first leading and progressing cause of mandibular fractures is brawls. Surgical treatment generally consists in fixation of the bone fracture. Maxillary locking is still associated in 33% of patients, but with a 50% shorter duration. Complications routinely arise because of poor bad oral hygiene.

[Giant-cell tumors: three recurrent cases in young patients]. / Tumeurs à cellules géantes: à propos de trois cas récidivants chez des sujets jeunes.

INTRODUCTION: True giant-cell tumor is a rare jaw osteolytic benign tumor belonging to the larger family of giant-cell tumors. It is particular because of the risk of recurrence and potential metastatic spread. OBSERVATION: Since 1973, we have managed four cases of true giant-cell tumors in our unit. The three cases reported here concerned young patients who developed recurrence after tumorectomy-curettage. DISCUSSION: Based on a literature review we defined this entity among the other giant-cell tumors. We emphasize the importance of early definitive diagnosis based on rigorous clinical and radiological confrontations. Because of its benign nature, the most conservative surgical treatment (tumorectomy-curettage) is generally proposed for the young patient. We noted however that in the three cases presented here, more radical surgical treatment with an enlarged tumorectomy removing the adjacent bone was advisable because of the high risk of recurrence and metastasis.

[Double-barrel fibular free flap for mandibular reconstruction: beneficial alternative for dental implanted rehabilitation (5 cases)]. / Lambeau libre de péroné en double barre: intérêt du montage dans les reconstructions mandibulaires pour une réhabilitation prothétique sur implants (5 cas).

INTRODUCTION: As major loss of mandibular bone stock requires a vascularized transfer, fibula free flap reconstruction is considered to be the best free flap for its length and reliability. Its main advantage is to accept dental implants. Single or double-barrel reconstruction can be performed. Double-barrel reconstruction is generally preferred because the bone superposition offers enough height to allow dental implants. MATERIAL AND METHODS: We reviewed five selected cases of double-barrel fibula free flap adaptive mandibular reconstruction performed among a series of 11 oral rehabilitations with planned dental implants, focusing on the technical aspects. RESULTS: Today, dental rehabilitation has been achieved in three double-barrel fibula flaps. Details are reported concerning the implant step. DISCUSSION: In this perspective, we discuss the choice of the reconstructive technique in order to obtain adequate bone height. Early in our experience and for different reasons discussed in the text, we used a single barrel fibula flap. This technique provided sufficient height in some cases, but had to be completed by bone grafts in few patients. Our experience illustrates the usefulness of the double barrel technique which provide definitive bone height sufficient for dental implants. The double-barreled technique should be considered as the best solution.

Facial malignant peripheral nerve sheath tumors.

BACKGROUND/PURPOSE: Malignant peripheral nerve sheath tumors (MPNSTs) are rare neoplasms, only sporadically reported involving the maxillo-mandibular region (ten cases with CT or MR data). We present here five additional cases with CT and MR findings along with an extensive review of the literature. RESULTS: Accurate diagnosis of MPNSTs is difficult because pathological like radiological criteria are often non specific. Radiological features display a large spectrum of abnormalities from a well-delineated heterogeneous appearance simulating benign schwannoma to extensive erosive patterns. Their development along the mandibular nerve, the absence of any target or central dot sign, their strong predominant peripheral enhancement must suggest the diagnosis of MPNSTs while irregular bone destruction or the detection of poorly defined margins with muscular infiltration are the most reliable criteria of malignancy. Unfortunately, MPNSTs also display a considerably varied histology. Careful clinical and radiological correlation should bring pathologists to examining large samples of the lesion to better evaluate the overall organisation of the lesion and detect some evocative criteria often only present in some areas of the sample as the peculiar curlicue or whorled arrangement of the spindle cells or the alternation of densely cellular fascicles with hypocellular, myxoid zones. Focal, limited immunostaining for S-100 protein is one of the most important additional criterion. CONCLUSION: If accurate early diagnosis often remains difficult, careful correlation of clinical, pathological and radiological data should in most cases suggest a diagnosis of MPNSTs which display a poor prognosis and requires early and adapted treatment.

Endoscopic excision of forehead lipomas.

Endoscopic surgery is a significant addition in the maxillofacial surgeon's armamentarium. Authors' experience of endoscopically assisted removal of forehead lipomas has been presented. The endoscopic technique permits to hide minimal scars in the hair. The magnification allows a good identification of anatomical structures and thus decreases the risk of numbness. The main disadvantages of this technique are the more expensive equipment and the steep learning curve. But with the expansion of endoscopic techniques, prices should decline and the duration of operations always lessens with experience. This technique might possibly appear to offer a new standard procedure for removal of forehead lipomas, notably in patients with keloid history or high aesthetic concerns.

Effects of crude oil on phospholipid fatty acid compositions of marine hydrocarbon degraders: estimation of the bacterial membrane fluidity.

In this study, we investigated, in vitro, the effects of petroleum hydrocarbons on the phospholipid ester-linked fatty acid composition of Corynebacterium sp. Strain 8. The usual ratio of monounsaturated fatty acids E/Z (or trans/cis) was calculated. This ratio led to unexpected results because we found similar values for growths on either a hydrophobic substrate (crude oil) or a soluble carbon source (rich medium). The use of such an indicator seemed limited for monitoring an environmental stress, so we proposed an index based on the homeoviscous adaptation theory. A membrane viscosity index was defined and applied to Corynebacterium sp. Strain 8 (in vitro growth) and to a sedimentary community (in situ experiment). The results allowed us to estimate the membrane fluidity of both an isolated strain and a bacterial community in accordance with the medium hydrophobicity.

Comparison of n-eicosane and phenanthrene removal by pure and mixed cultures of two marine bacteria.

The biotransformation activities of two hydrocarbonoclastic marine bacteria, Corynebacterium sp. and Sphingomonas sp. 2MPII, on n-eicosane and phenanthrene were investigated. During a 56-day experiment, in pure and mixed cultures, Corynebacterium sp. and Sphingomonas sp. 2MPII removed about 70% of the initial n-eicosane and phenanthrene concentrations (1 and 0.4 g L(-1), respectively). In pure cultures, culturable cell abundances increased over time, from 0.8 to 8.6 x 10(-11) CFU L(-1) (Corynebacterium sp.) and from 2.1 to 16 x 10(-11) CFU L(-1) (Sphingomonas sp. 2MPII ) but remained barely constant in mixed cultures. We defined a biotransformation index based on the number of culturable cells rather than the culture protein content, with the biotransformation cell yield (BCY) expressed in grams hydrocarbon CFU(-1) per day to better characterize hydrocarbon removal in pure and mixed cultures. The BCY was markedly higher in mixed than in pure cultures, increasing by a factor of 2-10.7 and 2.3-4.7 for n-eicosane and phenanthrene removal, respectively.