Search

This study aimed to analyse the possible linkage between diabetes mellitus (DM) and oral cancer among Austrians.We performed a retrospective DM and/or impaired fasting glucose (IFG) screening in 573 patients who underwent maxillofacial surgery under general anaesthesia between January 1, 2018 and December 31, 2019.Of the total patients, 26.5% (n=152) had cancer diagnosis, whereas the remaining 73.5% (n=421) formed the control group. The prevalence of glucose metabolism disorder (GMD) was significantly (p0.00001) more common among cancer patients (59.9% vs. 36.5%). Squamous cell carcinoma and sublingual tumours represented the most common tumour type (93.4%) and location (35.5%), respectively. Smoking was significantly (p=0.00093) more common within the cancer group.Our data suggest an association between GMD and oral cancer.

CAGE20-8 cruise onboard RV “Kronprins Haakon” aimed to survey the natural seepage of methane along the NE Greenland margin. Based on multibeam echosounder surveys, water column mapping for gas flares, and shallow seismic, gravity coring and multicoring were conducted. Due to heavy ice conditions, the vessel did not reach the shelf, however, survey along the continental slope were conducted. From a number of acoustic profiles and sediment cores, we will pursue the investigations of natural seepage related to glacial variability and sea ice fluctuations over the coming months. The cruise may be known as: CAGE20_8

The cruise visited several areas in Hopendjupet, and Sentralbankrenna in the central Barents Sea, and had the following scientific objectives: Surveying and sampling of gas seepage associated with known and assumed sandstone reservoirs sub-cropping at the sea floor due to erosion of overlying cap rocks in Hopendjupet and Sentralbanken Surveying and sampling of gas seepage related to leakage along faults and geological structures breaching the seafloor in Hopendjupet and Sentralbanken Sampling of oil in sea surface slicks and within shallow sediment cores Surveying of landforms associated with the retreat of the Barents Sea Ice Sheet in the outer Sentralbankrenna area The cruise may be known as: CAGE21_4

This contribution gives an overview of the use, therapeutic effects and side effects of the antibiotic substance Metronidazole. Metronidazole is effective in the treatment support of paradontitis, microbial-caused halitosis, perioral skin infections and odontogenic hard or soft tissue abscess formations related to anaerobic bacterial infections. Due to its anti- parasitic effect, Metronidazole is also effective in the treatment of protozoa. In adults and children from 12 years on, 200 mg Metronidazole to a maximum of 2000 mg Metronidazole per day can be administered. In children below 12 years of age, an antibiotic dose of Metronidazole between 20 to 30 mg per kilogram body weight is advised.

The use of local anesthetics is known to be safe and efficient in surgical and dental treatments. Local anesthetics are essential in dentistry for appropriate pain control as they inhibit nociception generated during surgical and dental procedures. However, among other precautions, attention has to be paid to the individual maximum dose of the local anesthetics that is administered. This is especially important for children who are, due to their low body weight, more prone to adverse events following substance overdose. Therefore, this contribution gives advice for general dentists on the accurate use and maximum dose of local anesthetics in children.

Extensive defects in the head and neck area often require the use of advanced free flap reconstruction techniques. In this study, the thoracodorsal perforator-scapular free flap technique based on the angular artery (TDAP-Scap-aa flap) was postoperatively evaluated regarding the quality of life and the donor site morbidity using the standardized SF-36 and DASH questionnaires (short form health 36 and disabilities of the arm, shoulder and hand scores). Over a five-year period (2016–2020), 20 selected cases (n = 20) requiring both soft and hard tissue reconstruction were assessed. On average, the harvested microvascular free flaps consisted of 7.8 ± 2.1 cm hard tissue and 86 ± 49.8 cm2 soft tissue components. At the donor site (subscapular region), only a mild morbidity was observed (DASH score: 21.74 ± 7.3 points). When comparing the patients’ postoperative quality of life to the established values of the healthy German norm population, the observed SF-36 values were within the upper third (>66%) of these established norm values in almost all quality-of-life subcategories. The mild donor site morbidity and the observed quality of life indicate only a small postoperative impairment when using the TDAP-Scap-aa free flap for the reconstruction of extensive maxillofacial defects.

Hyperparathyroidism-jaw-tumor syndrome (HPT-JTS) is a rare autosomal dominant disorder. A typical manifestation of HPT-JTS is the association of jaw-ossifying fibroma with primary hyperparathyroidism. Due to its rarity and diversity in its manifestations, it is a challenging diagnosis. A 33-year-old woman was referred due to painful swelling of the right maxilla suggestive of malignancy. The clinical presentations were not conclusive until she underwent F18-fluorodeoxyglucose positron emission tomography/computed tomography (F18-FDG PET/CT). F18-FDG PET/CT proved to be a useful tool to assist the clinicians in visualizing the "bigger picture" and, therefore all manifestation as pieces of "one puzzle."

Large head and neck squamous cell carcinoma (HNSCC) tumors affecting the mandible require a versatile reconstruction to maintain form, function, and quality of life. Large defect reconstruction of soft and hard tissue in the head and neck necessitates, at best, one vascular system including various tissues by large dimensions. The subscapular flap system seems to meet these standards. A retrospective study was conducted focusing on clinical data, including an analysis of the quality of life with the European Organization for Research and Treatment of Cancer (EORTC) Quality of Life Questionnaires, (QLQ-C30 and QLQ-H&amp, N43). A total of 154 patients (122 males, 32 females, age range: 31&ndash, 71 years, mean: 54.5 years) treated at our department from 1983 through to 2019 were included. Of the subscapular system free flaps (SFFs), 147 were based on the angular artery branch of the thoracodorsal pedicle (95.45%), and the remaining seven cases (4.55%) were lateral scapular border flaps. Mean mandible defect length was 7.3 cm. The mean skin paddle dimension was 86.8 cm2. The most common recipient artery was the thyroid superior artery (79.22%). Major postoperative complications occurred in 13 patients (8.44%). This study confirms that SFFs offer excellent soft and hard tissue quality, component independence, a large arc of rotation length, and a large gauge of pedicle, making them the gold standard for the reconstruction of large composite defects of mandibular HNSCC tumors.

Gas hydrates exist within a relatively narrow envelope of thermal and pressure conditions, small changes in which may lead to widespread dissociation and methane release. During past glacials, extensive ice sheets covered the continental margins of the Arctic Basin yielding ideal high pressure and low temperature conditions for the sequestration of thermogenic and biogenic methane in hydrate-bearing subglacial sediments. On ice sheet retreat at the end of the last glacial, these hydrate reservoirs experienced major perturbations in thermal and pressure conditions leading to decomposition and methane mobilization over a variety of magnitude, temporal and spatial scales. Using geophysical data to constrain state-of-the-art ice sheet/gas hydrate modelling, we investigate how past Northern Hemisphere ice sheets modulated carbon sequestration and release. Our results provide the first quantitative assessment of widespread subglacial hydrate formation and mobilization during the last glacial, yields insights into global carbon cycle dynamics and informs potential future atmospheric greenhouse composition and feedbacks associated with shrinkage of the contemporary cryosphere.

Purpose The reconstruction of oromandibular defects can be challenging, particularly when considerable amounts of bone and soft tissues are lost. In such cases, the use of a single flap may be unsatisfactory and a concomitant free flap is needed. Here we present a chimeric, thoracodorsal perforator-scapular free flap based on the angular artery of the subscapular system (TDAP-Scap-aa) as an alternative technique for single flap reconstruction of extensive oromandibular defects. Materials and methods The authors studied patients who underwent reconstructions of extensive oromandibular defects with a TDAP-Scap-aa free flap. The operative technique and the clinical experiences are described. Postoperatively, surgical complications were classified with the Clavien-Dindo Classification. Results Five male patients (59.4 ± 8.8 years) were treated with the TDAP-Scap-aa. Average sizes for harvested hard and soft tissue components, which are both included in the flap and completely independently from each other, were 10.4 ± 1.5 cm of bone length, 2.6 ± 0.3 cm of bone height, 11.6 ± 4.8 cm of skin paddle length and 8.4 ± 1.7 cm of skin paddle width. The overall mean operation time (cut-suture) was 14.6 ± 0.9 h. The postoperative follow-up was 6 months. No complications requiring surgical treatment as well as donor site nerve damages were observed. Conclusions In comparison to other double free flaps, the TDAP-Scap-aa offers several advantages such as higher amounts of hard and soft tissues without prolonged operation times, and provides satisfying aesthetic outcomes and little donor site morbidity due to the preservation of muscle and nerve structures. Therefore, the TDAP-Scap-aa constitutes a clinically reliable alternative in extensive oromandibular defect reconstruction.

Purpose The aim of this article is to present our experience treating fractures of the condylar base with a modification of the high submandibular approach (HSA). Materials and methods Between June 2012 and April 2015, 44 fractures of the condylar base were treated in the Department of Oral and Maxillofacial Surgery of the Medical Hospital of Graz using the modified HSA. Results We did not observe any damage (even transient) to the facial nerve or any complication related to violation of the parotid capsule (such as a salivary fistula, Frey syndrome, or a sialocele). Conclusions This approach provides good access to the condylar base, ensuring easier internal fixation, excellent protection of the facial nerve and parotid gland, and good cosmetic results.

The innovative TriLock Bridging Plate System (Medartis AG, Switzerland) was developed to reduce common complications related to conventional mandibular reconstruction plates. The novelties regarding the plating system concern the cross-strut structure in the centerpiece, the bendable side elements and the reduction of the plate's thickness to 2.0 mm 4 different models are available, which cover lateral and central segmental mandibular defects. The plating system has only been introduced at selected maxillofacial units so far and clinical assessment is still lacking. Thus, the aim of the study was to analyze the novel Bridging Plate system in terms of its clinical applicability, rate of trimming and postoperative outcomes in a first investigation over 6 months. The study includes 25 patients with segmental mandibular resection, who underwent reconstruction with TriLock Bridging Plates. According to the assessment parameters, excellent clinical applicability was stated in 48%. The overall trimming rate was found to be 88%. Mostly adaptions to the distal bendable elements of lateral plates were performed. The occurrence of postoperative complications was 16%. Plate fracture occurred in 4%. With reference to the results, the novel plating system represents a viable method for segmental mandibular reconstruction, however, further evaluation is needed, for a more detailed analyzation.

Objectives Determination of tumor margins in patients with squamous cell carcinoma of the head and neck (SCCHN) is mostly based on preoperative magnetic resonance imaging (MRI) or computed tomography scans (CT). Local recurrence of disease is often correlated with the presence of positive resection margins after surgical treatment. Positron emission tomography/computed tomography (PET/CT) imaging plays a crucial role in the assessment of patients with SCCHN. The purpose of this study was to determine whether PET/CT could predict tumor extension. Methods In 12 patients who underwent surgical treatment of primary SCCHN (Stage III-IV) F18-FDG PET/CT image-fusion was performed on a 3D navigation-system based workstation. Image-guided needle biopsies were obtained from four different, color-coded metabolic areas within the tumor. The histopathological findings were correlated with findings on corresponding PET/CT scans. Results 81.3% of biopsies from the central area were positive. Specimens taken from the outer metabolic zone were positive in 66.7% of the patients. The highest incidence of positive biopsies was found in the zone adjacent to the outermost area. There was a statistically significant difference in positive tumor histopathology when comparing the various metabolic zones (p = 0.03). Conclusion Exact determination of tumor is an important research topic, although results remain controversial. The results of this study suggest that in some cases PET scans may overestimate tumor extension.

Intraorbital tumours are often undetected for a long period and may lead to compression of the optic nerve and loss of vision. Although CT, MRI's and ultrasound can help in determining the probable diagnosis, most orbital tumours are only diagnosed by surgical biopsy. In intraconal lesions this may prove especially difficult as the expansions are situated next to sensitive anatomical structures (eye bulb, optic nerve). In search of a minimally invasive access to the intraconal region, we describe a method of a three-dimensional, image-guided biopsy of orbital tumours using a combined technique of hardware fusion between 18 F-FDG Positron Emission Tomography ( 18 F-FDG PET), magnetic resonance imaging (MRI) and Computed Tomography (CT). Method and material We present 6 patients with a total of 7 intraorbital lesions, all of them suffering from diplopia and/or exophthalmos. There were 3 female and 3 male patients. The patients age ranged from 20 to 75 years. One of the patients showed beginning loss of vision. Another of the patients had lesions in both orbits. The decision to obtain image-guided needle biopsies for treatment planning was discussed and decided at an interdisciplinary board comprising other sub-specialities (ophthalmology, neurosurgery, maxillofacial surgery, ENT, plastic surgery). All patients underwent 3D imaging preoperatively ( 18 F-FDG PET/CT or 18 F-FDG PET/CT plus MRI). Data was transferred to 3D navigation system. Access to the lesions was planned preoperatively on a workstation monitor. Biopsy-needles were then calibrated intraoperatively and all patients underwent three-dimensional image-guided needle biopsies under general anaesthesia. Results 7 biopsies were performed. The histologic subtype was idiopathic orbital inflammation in 2 lesions, lymphoma in 2, Merkel cell carcinoma in 1, hamartoma in 1 and 1 malignant melanoma. The different pathologies were subsequently treated in consideration of the actual state of the art. In cases where surgical removal of the lesion was performed the histological diagnosis was confirmed in all cases. Conclusion There is a wide range of possible treatment modalities for orbital tumours depending on the nature of the lesion. Histological diagnosis is mandatory to select the proper management and operation. The presented method allows minimal-invasive biopsy even in deep intraconal lesions, enabling the surgeon to spare critical anatomical structures. Vascular lesions such as cavernous haemangioma, tumour of the lacrimal gland or dermoid cysts present a contraindication and have to be excluded.

Upper third molar exodontia is one of the most common and simple dentoalveolar surgical procedures. Complications, such as bleeding from the posterior superior alveolar vessels are rare but potentially dangerous. This article describes a case of postoperative hematoma of the temporal and infratemporal fossa after simple upper third molar extraction. The etiology of this uncommon complication could be rupture of the posterior superior alveolar vessels during injection of the local anesthetic. The absence of concomitant tearing of the periosteal envelope overlying the maxillary tuberosity may force blood backwards and upwards along the external pterygoid muscle into the infratemporal fossa and further along the anterior border of the temporal muscle. In two previously reported cases, the hemorrhage spread up into the infratemporal fossa and through the inferior orbital fissure into the orbit. In the case described here the bleeding stopped spontaneously; nevertheless, inpatient observation was indicated because of the possibility that a retrobulbar hematoma might develop. Uncomplicated upper third molar extraction is one of the most common procedures of oral and maxillofacial surgery but can nevertheless trigger unexpected late complications, such as bleeding into the deep skull spaces. In such cases referral to an oral maxillofacial surgeon is essential for appropriate follow-up and management.

Synovial chondromatosis (SC) is a rare metaplastic disease of the larger joints. It is rarely observed in smaller joints, especially in the temporomandibular joint (TMJ). This disease is considered to be metaplastic and shows no malignant tendencies, but can become locally aggressive, erode the cranial base, and even spread intracranially. To date, nine cases of spread into the intracranial space have been reported in the literature; however, the disease remained extradural in all cases. The authors present a review of the literature and report the case of a 70-year-old man with SC of the right TMJ that had eroded the cranial base, reaching the dura mater; a large intracranial mass was not present. The disease was considered to be stage 3 according to Milgram's classification. The patient was treated surgically, the tumour mass was removed, reconstruction of the cranial base was performed using titanium mesh, and the joint was reconstructed with a temporal muscle interposition flap. Diagnostic images and intraoperative photographs are also presented.

Water tank experiments were performed in order to investigate the behaviour of currents in pockmarks. A particle-seeded flow was visualised and quantified with the aid of the particle tracking velocimetry technique. The employed analogue pockmark is a 1:100 idealised scale model of a natural pockmark, while the highest Reynolds number in the experiments was one order of magnitude smaller than in nature. Interaction of the flow with the pockmark geometry resulted in an upwelling current downstream of the pockmark centre, along with enhanced water turbulence in the depression. Scaling-up the experimental measurements, it is found that the upwelling would be capable of preventing the settling of particles as large as very fine sand. Furthermore, the increased turbulence would support the suspended fine material, which can thus be transported away before settling. The net effect for a variable-direction near-bed current over long periods of time would be to winnow the settling sediments and reduce the sedimentation rate in pockmarks. These mechanisms may be responsible for the observed lack of sediment infill and the typical presence of relatively coarser sediments inside pockmarks compared to the surrounding bed. In contrast, sediments transported as bedload are likely to be deposited in pockmarks because of the weakening of near-bed currents as well as lateral flow convergence associated with the upwelling. Bedload, however, may not be the dominant mode of sediment transport in areas covered by cohesive sediments, where pockmarks are found.

Surgically assisted rapid maxillary expansion (SARME) is commonly used to correct maxillary transverse deficiency. The aim of this study was to analyse the need for intraoperative liberation of the nasal septum during the procedure. SARME was performed in 25 patients by combining a lateral osteotomy with an inter-radicular maxillary osteotomy. The deviation of the nasal septum after SARME was evaluated by comparing measurements between radiologically defined landmarks on pre- and postoperative computed tomographic images. Two defined angles (angle I, between crista galli-symphysis mandibulae and crista galli-septum nasi; angle II, between maxillary plane and septum nasi) were measured based on four representative planes and septal movement was analysed. The mean changes in angles I (0.03° ± 0.78°) and II (0.25° ± 1.04°) did not differ significantly from zero (p = 0.87 and p = 0.24, respectively). Observed variations and displacements were considered to be acceptable because they were insignificant in every respect. Intranasal airway function was also examined pre- and postoperatively to evaluate any loss of ventilation. The described surgical technique is a successful method of maxillary segment distraction. The authors found no compelling reason to release the nasal septum in the context of SARME.

Amyloidosis is a heterogeneous group of disorders caused by the extracellular deposition of a fibrillar protein called amyloid. Amyloid involvement of the tongue is almost universally secondary to systemic disease. The clinical manifestations result from the progressive extracellular deposition of amyloid within the suprahyoid muscles. In the late stages, the progressive enlargement of the tongue causes hypo- and oropharyngeal blockage, with obstruction of the upper airways. Conservative excision is a satisfactory treatment for local amyloid masses; the role of surgery in systemic forms is controversial. The authors present a case of systemic primary amyloidosis of the tongue treated surgically by a partial glossectomy via a pull-through approach and discuss the indications and rationale for surgical intervention.

a a t o i s Maxillofacial surgeons are increasingly involved in the surgical management of patients affected by severe obstructive sleep apnea syndrome (OSAS) because of the high success rate of maxillomandibular advancement (MMA). This increase has occurred in the absence of a correlation between the dimensions of the upper airways corresponding to a resolution of OSAS. There is also no mathematical correlation between bimaxillary advancement and resulting change in dimensions of the posterior airway space (PAS). Most surgeons now agree that the best results are achieved by advancing the jaw as much as possible, maintaining an acceptable functional and esthetic result. The criteria for patient seection included severe OSAS patients unsuitable for ndergo conventional procedures and able to receive a aximum advancement. Although MMA is a life-saving treatment in severe SAS patients, esthetic considerations cannot be nelected, because these patients usually exhibit normal raniofacial skeletal morphology. Therefore the limit f the MMA is represented by that beyond which an nacceptable deformity would be created. Technical mprovements are necessary to make extreme bimaxllary advancements more esthetically acceptable. Reent review of opinions held for the last decade rearding the treatment of facial deformity has led us to xploit a method from the past, the counterclockwise otation of the occlusal plane, which was previously sed in correcting severe Class II skeletal deformity

The synovitis, acne, pustulosis, hyperostosis, and osteitis (SAPHO) syndrome is a rare syndrome of unknown etiology. Involvement of the mandible is found in almost 10% of cases. In the literature, conservative treatment is recommended most often, because decortication and partial resection are found to be ineffective and of temporary profit. We report a case of SAPHO syndrome in a 44-year-old women with unilateral hyperostosis of the mandible and massive painful swelling of the surrounding soft tissues. Owing to facial disfiguration and pain, resection of the affected bone followed by immediate reconstruction with a microvascular iliac crest flap were performed. The aim of this paper was to present the necessity of surgical intervention in SAPHO syndrome of the mandible in cases of esthetic and functional limitation.

Summary Local recurrent of disease in advanced carcinomas of the head and neck is strongly correlated with the presence of positive or close resection margins after operative treatment. The purpose of this study is to present a new method of assessing resection margins intraoperatively using image-guided surgery based on positron emission tomography/computed tomography (PET/CT) image fusion. In 6 patients who underwent surgical treatment of head and neck stage for T4a–T4b carcinomas PET/CT image fusion was done on the workstation of a 3D-navigation system. Intraoperative image-guided navigation of the defect following surgical ablation of the tumour was performed in every patient. Intraoperative navigation of the ablative defect showed an unsafe resection margin in 4 patients. In three of these patients additional image-guided resection allowed local control of the tumour to be achieved. In one patient additional resection was not possible due to skull base invasion. The histopathological exam of the four tumour specimens confirmed positive or close resection margins. The current results suggest that intraoperative control of the surgical margins using a 3D-navigation system based on PET/CT image fusion can be a useful tool to assess and improve local control in advanced cancer of the head and neck.

Osteomyelitis is an inflammatory process involving cortical and cancellous bone. In the maxillofacial region, the mandible is the most frequently affected bone. In the vast majority, a bacterial focus can be identified as the origin of the disease. Chronic progress of the disease may lead to destruction of mandibular bony structures, resulting in mild or severe loss of function if no adequate treatment is applied. In some cases, the etiology of osteomyelitis remains unclear. Review of literature revealed two cases of necrosis of the mandibular condyle caused by primary osteomyelitis. We report a case of primary osteomyelitis of the mandibular condyle in a 51-year-old woman. Radiography revealed an almost complete destruction of the right mandibular condyle, resulting in malocclusion. The patient was treated with long-term antibiotics. No surgical intervention had been performed. After remission of the symptoms, the malocclusion had been corrected prosthetically. After a 4-year follow up period, the occlusion is stabile and there are no signs of progression of the disease.

The surgical treatment of orbital floor fracture, a common facial injury, is not a risk-free procedure. Complications after orbital surgery can include infection, implant migration, mydriasis, epiphora, persistent diplopia, enophthalmos, infraorbital numbness, retrobulbar hemorrhage, and blindness. Blindness has been ascribed to retrobulbar hematoma in almost 50% of cases. In our experience, blood collection above the polydioxanone sheet after the treatment of orbital floor fracture can be caused by the tight adhesion of the sheet to the bony edges of the fracture. Here, we present a simple procedure to avoid this potentially dangerous complication.

A 53-year-old woman with modest protrusion of the right eye was referred to our outpatient department from the ophthalmology department. She had been noticing blurred vision for the previous 2 years and was referred by her ophthalmologist because of optic nerve atrophy. The patient’s vision at the time was 20/20, and she reported moderate double vision. On examination, a loss of red/ green perception, decreased contrast sensitivity, and a small central scotoma in the visual field were observed. Magnetic resonance imaging (MRI) showed a 4.5 1.5 –cm intraconal mass medial to the lateral rectus muscle nd dorsal to the orbit, with extension to the superior rbital fissure (Fig 1). The optic nerve was displaced medilly but showed no morphologic alteration. However, intraranial changes could not be excluded. Computed tomogaphy was used to plan an interdisciplinary approach with he neurosurgeon. After a lateral orbitotomy was performed with a piezolectric osteotome, the Tenon capsule was opened through sharp incision. A firm elastic mass, which could be shifted ownward by blunt dissection, was palpated directly under he lateral rectus muscle. Directly beneath it, a vascularized, ncapsulated expansion surrounded by fat was seen (Fig 2). mmediate fresh-frozen sections were taken to confirm the enign nature of the lesion. Microscopic examination of the urgical specimens after hematoxylin-eosin staining showed ntoni A and B areas (Fig 3). The mass was dissected arefully along the enveloping tissue, up to the superior rbital fissure. To avoid further trauma to the abducens erve, the capsule was left in place. Immediately after the intervention, there was no amelioation of the ocular symptoms. Visual acuity remained at 0/20, the double vision was unchanged, the loss of color ision and decreased contrast sensitivity were still present, nd the scotoma in the visual field remained stable. For the ight eye, abduction was only possible 10° before the pri

Objective Due to the increase in the number and complexity of surgical procedures, available to craniomaxillofacial surgeons, allied to the rapid progress of technological developments, the use and production of 3D models has become important, especially for planning complex cases. The radiation exposure of additional CT based examinations is always subject to debate, so the feasibility of producing 3D models for surgical planning based on MRI imaging has been raised. Material and methods 12 male and 3 female patients ( n = 15) between 47 and 84 years of age (mean age = 65) were selected in a prospective study. Both magnetic resonance and computed tomography data sets of the facial bones were collected. Two milled models per patient were prepared: one based on the MRI scan and one based on the CT scan. The milled models were compared in a coordinative surveying procedure within 7 representative distances using a tentative measurement method. Results Difference values between CT and MRI based models ranged from 0.1 mm to 5.9 mm. On average MRI based models were smaller by 0.381 mm (SD 1.176 mm) than those on CT based. The accuracy of models based on MRI data was similar to those based on CT data. MRI based three dimensional milled models provide precise structure accuracy.

The authors present a modification of the preauricular approach that improves the exposure of the condyle whilst reducing diacapitular and condylar neck fractures. The incision is a combination of the hockey-stick and endaural incisions. Its inferior part runs within the ear on the posterior face of the tragus; the tragal cartilage is transected together with the retrotragal skin and included in the anterior skin flap. Between May 2009 and December 2010, 16 patients with diacapitular or condylar neck fractures were treated with this approach. All patients showed good occlusion postoperatively and satisfactory aesthetic results. No infection or cartilage necrosis was observed in this series. This approach improves the exposure of the condylar head during the reduction of diacapitular and condylar neck fractures, ensuring easier internal fixation and good cosmetic results.

Inferior alveolar nerve block (IANB) anesthesia is a common local anesthetic procedure. Although IANB anesthesia is known for its safety, complications can still occur. Today immediately or delayed occurring disorders following IANB anesthesia and their treatment are well-recognized. We present a case of a patient who developed a symptomatic abscess in the pterygoid region as a result of several inferior alveolar nerve injections. Clinical symptoms included diffuse pain, reduced mouth opening and jaw's hypomobility and were persistent under a first step conservative treatment. Since image-based navigated interventions have gained in importance and are used for various procedures a navigated surgical intervention was initiated as a second step therapy. Thus precise, atraumatic surgical intervention was performed by an optical tracking system in a difficult anatomical region. A symptomatic abscess was treated by a computed tomography-based navigated surgical intervention at our department. Advantages and disadvantages of this treatment strategy are evaluated.