Three lateral osteotomy designs for bilateral sagittal split osteotomy: biomechanical evaluation with three-dimensional finite element analysis

<p>Abstract</p> <p>Background</p> <p>The location of the lateral osteotomy cut during bilateral sagittal split osteotomy (BSSO) varies according to the surgeon's preference, and no consensus has been reached regarding the ideal location from the perspective of biomechanics. The purpose of this study was to evaluate the mechanical behavior of the mandible and screw-miniplate system among three lateral osteotomy designs for BSSO by using three-dimensional (3-D) finite element analysis (FEA).</p> <p>Methods</p> <p>The Trauner-Obwegeser (TO), Obwegeser (Ob), and Obwegeser-Dal Pont (OD) methods were used for BSSO. In all the FEA simulations, the distal segments were advanced by 5 mm. Each model was fixed by using miniplates. These were applied at four different locations, including along Champy's lines, to give 12 different FEA miniplate fixation methods. We examined these models under two different loads.</p> <p>Results</p> <p>The magnitudes of tooth displacement, the maximum bone stress in the vicinity of the screws, and the maximum stress on the screw-miniplate system were less in the OD method than in the Ob and TO methods at all the miniplate locations. In addition, Champy's lines models were less than those at the other miniplate locations.</p> <p>Conclusions</p> <p>The OD method allows greater mechanical stability of the mandible than the other two techniques. Further, miniplates placed along Champy's lines provide greater mechanical advantage than those placed at other locations.</p

Submandibular gland mucocele: Report of two cases

Submandibular gland mucocele should be remembered in the differential diagnosis of swelling at the submandibular triangle. In the cystic lesion of the submandibular area, the biochemical analysis of aspirated material for amylase should be performed. The cases with submandibular gland mucocele should be treated by removing the lesion with both the submandibular and the sublingual glands

Management of parapharyngeal space tumors

In this study, we aimed to investigate the influence of the surgical approaches for the parapharyngeal space tumors. Eighteen patients with parapharyngeal space tumors diagnosed and treated at our clinic between 1992 and 2001 were included in this study. Surgical techniques used included transcervical, transparotid, transcervical-transmandibular, and infratempoRal-A approaches depending on tumor size, location, vascularity, and malignant potential. Postoperative radiation therapy was applied in all malignant tumor. Postoperative morbidity, complications, and recurrence were evaluated. We found that 55.6 % of the PPS tumor were of salivary gland origin, 27.8 % were neurogenic, and 16.6% were miscellaneous. Of the four surgical techniques, transcervical approach were used most commonly, Postoperative morbidities were at acceptable levels. Our surgical survival rates were 100% for benign and 40% for malignant PPS tumors after a mean follow-up of 54 months

Hydatid cyst of the submandibular salivary gland in a child

The majority of hydatid cysts are seen in the liver and lungs. In countries where Echinococcus infestation is common, high index of suspicion is required for hydatosis and although it is a rare location, a hydatid cyst should be considered in the differential diagnosis of the cervical lesions in order to avoid any dangerous complication such as untreatable multiple hydatosis or a fatal anaphylactic reaction. Surgical removal without causing any spillage of its contents is the most effective treatment. To the best of our knowledge, only one submandibular gland hydatid cyst case in a child has been reported. A case of 9-year-old male with hydatid cyst of the submandibular salivary gland is presented. The literature was reviewed and characteristics of the disease were discussed. © 2006 Elsevier Ireland Ltd. All rights reserved

Biocompatibility of vitallium as ossicular reconstruction material in the middle ear: experimental animal study

Conclusion. Although long-term data will be necessary for confirmation, the result of this preliminary study indicates that vitallium may be a good alternative material for ossicular replacement prostheses in the middle ear. Objectives. To investigate the biocompatibility of vitallium (Co-Cr-Mo) as ossicular reconstruction material in the rabbit middle ear, and to compare the results with those obtained with titanium, well known as a highly biocompatible material, and non-implanted control groups. Material and methods. Eighteen female New Zealand White rabbits were anesthetized. The tympanomeatal flap was elevated and 12 vitallium and 12 titanium implants were placed in the bulla away from the ossicles in 24 middle ears. Six rabbits were used as non-implanted controls. All animals were sacrificed under general anesthesia on the 180th day after implantation. The temporal bones were removed, fixed in 10% buffered paraformaldehyde and decalcified for a week in EDTA. Tissue samples were then prepared using an Autotechnicon and embedded in paraffin. Sections (30-mum thick) were cut with a microtome, stained with hematoxylin-eosin, von Gieson's stain and fibroblast growth factor (FGF) and examined under a light microscope. The numbers of lymphocytes, collagen fibers and FGF-positive cells were determined in all three groups. Results. There was no significant difference in the numbers of collagen fibers between the groups (P > 0.05). No significant differences were found in the numbers of lymphocytes and FGF-positive cells between the titanium and vitallium groups (p > 0.05). The differences in the numbers of lymphocytes and FGF-positive cells between the control and other groups were found to be significant (p < 0.05)

A modified technique to bypass the maxillary artery to supraclinoid internal carotid artery by using radial artery graft: an anatomical study

Objective: This study aims to examine the use of a radial artery graft for bypass of the maxillary artery (MA) to the supraclinoid internal carotid artery (ICA) in treating ICA occlusions. Study design and setting: This method was carried out on five adult cadaver sides. The MA was reached 1-2 cm inferior to the crista infratemporalis, following a frontotemporal craniotomy and a zygomatic arch osteotomy. Extradurally 2-3 cm lateral to the foramen rotundum, a hole was drilled in the sphenoid bone with a 4 mm tipped drill. A radial artery graft was passed through the hole to the inside of the dura. Before giving the infraorbital artery branch, the MA was dissected from the surrounding tissue and transected. The proximal end of the graft was anastomosed end-to-end with the MA and the distal end of the graft end-to-side with the supraclinoid ICA. Results: The mean calibre of the MA was 2.6 +/- 0.3 mm. The mean calibre of the proximal end of the radial artery graft was 2.5 +/- 0.25 mm and the distal end was 2.35 +/- 0.2 mm. The mean length of the radial artery graft was 4.0 +/- 0.5cm. Conclusion: This study suggested that the cases with ICA occlusion, which require high blood flow, may be treated as an alternative to current bypass methods requiring long vein grafts

Increased expression of epidermal growth factor receptors in the tracheal epithelia after topical mitomycin-C in rabbits

The aim is to examine histopathological changes and expression of epidermal growth factor receptor (EGFR) in tracheal epithelia caused by application of topical mitomycin-C (MMC) in rabbit model after the tracheotomy procedure. The conventional tracheotomy was performed in 16 rabbits. They were randomly divided into two equal groups. The first group was applied MMC at a concentration of 0.4 mg/ml around tracheotomy for 5 min, and the other group was not taken a treatment as a control. The animals were sacrificed at the end of 4 weeks. Their tracheas were evaluated with H&E and Masson's trichrome histochemically, and with antiepidermal growth factor receptor immunohistochemically. Results showed that there was no significant difference between MMC and control group for inflammatory cells (P = 0.09). The numbers of fibroblasts and subepithelial tissue thickness in the group exposed to MMC were significantly lower than the control group (P < 0.05). In contrast, the percentage of EGFR in the application of MMC group was significantly higher than the control croup (P < 0.05). The application of topical MMC on airway epithelia after tracheotomy showed significant elevation in the levels of epithelial EGFR expression compared to controls in a rabbit model. The activation of epithelial EGFR may facilitate epithelial healing, but further studies are needed to assess the effect of topical MMC on respiratory epithelia. (c) 2004 Elsevier Ireland Ltd. All rights reserved

Foley balloon placement for maxillofacial fractures [Maksillofasiyal kiriklarda foley kateter balonunun kullanimi.]

OBJECTIVES: The aim of the study was to evaluate the effectiveness of maxillary sinus Foley balloon placement in patients with maxillofacial fractures. PATIENTS AND METHODS: This study included 38 patients (10 females, 28 males; mean age 29.1+/-11.6; range 9 to 49 years) in whom Foley balloon placement and gauze packing were performed for blow-out, orbitozygomatic, or maxillary fractures. Sex and age distributions, etiology of trauma, localization of fractures, management, intraoperative and postoperative complications were evaluated. RESULTS: Eighteen patients had blow-out fractures, 15 patients had orbitozygomatic fractures, and five patients had Le Fort II-III fractures of the maxilla. Preoperatively, enophthalmos, diplopia, limited ocular motility, and facial asymmetry were found in 28.9%, 26.3%,18.4% and 65.8%, respectively. Sufficient maxillary sinus patency was obtained in 32 patients (84.2%). Enophthalmos, diplopia, limited ocular motility, and facial asymmetry were found in 13.2%, 7.9%, 5.3%, and 18.4% in the postoperative period, respectively. CONCLUSION: Maxillary Foley balloon placement should be preferred in the blow-out, orbitozygomatic, and maxillary fractures because it supports the orbital floor and provides sufficient maxillary sinus patency

Superficial temporal artery graft for bypass of the maxillary to proximal middle cerebral artery using a transantral approach: an anatomical and technical study

Conclusion. Using a transantral approach, we examined a new bypass of the maxillary artery ( MA) to proximal middle cerebral artery ( MCA). The caliber of the MA was suitable to provide sufficient blood flow. The length of the graft was shorter and it had a straighter course in the new technique than in previously described techniques. Objective. To examine a new bypass of the MA to proximal MCA using a transantral approach as an alternative to other forms of anterior circulation bypass surgery. Material and methods. The method was applied to five adult cadavers bilaterally. The MA and its branches were easily found after removal of the posterior sinus wall using a transantral approach. Then, a hole was created in the sphenoid bone 5 - 6 mm lateral to the posteroinferior edge of the superior orbital fissure extradurally. After the carotid and sylvian cisternae had been opened, the M2 segment of the MCA was exposed. The MA was transected just before the origin of the descending palatine artery branch. After opening the dura over the hole, the MA was passed through the hole to reach the intracranial cavity. The proximal side of the superficial temporal artery graft was anastomosed end- to- end with the MA and the distal side was anastomosed end- to- side with the M2 segment of the MCA. Results. The mean caliber of the MA was 2.4 +/- 0.3 mm before the origin of the descending palatine artery branch. The mean caliber of the largest trunk of the M2 segment of the MCA was 2.3 +/- 0.3 mm. The average length of the graft was 24 +/- 3 mm

Postauricular subcutaneous leiomyosarcoma

Superficial leiomyosarcomas are rare soft tissue tumors, most frequently involving the lower extremity. Leiomyosarcomas which could be misdiagnosis or delayed are very rare in the head and neck region. In this report, a 46-year-old man with postauricular leiomyosarcoma was presented. The tumor was totally excised with 3 cm margins. Immunohistochemically, the specimen showed reactivity for smooth muscle actin, vimentin, and desmin. No complications developed in the postoperative period and the patient was free of recurrence at the 26 months follow-up. Immunohistopathological examination is essential for an accurate histological diagnosis. The ENT surgeon should pay attention to superficial leiomyosarcoma with its specific behavior and treatment while evaluating the lesions in the head and neck region. (C) 2004 Elsevier Ireland Ltd. All rights reserved