The Effects of Preoperative Radiotherapy on Head and Neck Free Flap Anastomosis Success.

PURPOSE: The long-term survival benefit of neoadjuvant radiotherapy for oropharyngeal tumors is controversially discussed in the literature. To bring more light into this important debate, we evaluated our cases. PATIENTS AND METHODS: In this retrospective study the main focus was the relationship between neoadjuvant irradiation and anastomosis failure. Other influencing factors including previous operative treatment and tumor stage and type also were studied. RESULTS: In total, 7 anastomoses failed (total failure rate, 8.4%; n = 83); 1 of the 7 underwent neoadjuvant irradiation (failure rate, 3.1%; n = 32). All 7 anastomosis failures were in squamous cell carcinoma cases, with 5 of them staged as T4. CONCLUSION: Our data suggest that neoadjuvant radiotherapy for oropharyngeal carcinoma does not increase the risk of postoperative anastomosis failure compared with surgical reconstruction alone. Furthermore, the data suggest a correlation between the stage and type of tumor.

Fallpräsentation: Kiefergelenkbeschwerden als erstes Zeichen einer malignen Erkrankung.

CASE REPORT: TMJ-like symptoms as first sign of a tumorous disease. Metastasis as an uncommon origin of the symptoms (in German).

Frequency and anatomy of the retromolar canal - implications for the dental practice.

The retromolar canal (RMC) is an anatomical variant of the mandibular canal. Apart from blood vessels it also contains accessory nerve fibers and is clinically important, because its presence can account for failures of mandibular block anesthesias and in rare cases, injuries of its neurovascular bundle can lead to complications such as hemorrhages and dysesthesias. The aim of this retrospective case study was to analyze the frequency and anatomy of the RMC using cone beam computed tomography (CBCT) in order to draw conclusions for the dental practice. A total of 680 CBCT scans comprising 1,340 mandibular sides were evaluated. A total of 216 RMCs (16.12%) were found. The most common appearance of the canal (39.82%) corresponded to type Al (vertical course), whereas type C (horizontal course) occurred least often (6.02%). Mean measured values were 1.03 mm (SD=0.27mm) regarding the RMC diameter, 10.19 mm (SD=2.64mm) regarding the RMC height and 15.10 mm (SD=2.83 mm) regarding the distance of the RMC to the second molar. Neither demographic factors nor the spatial resolution of the CBCT had a statistically significant impact on the frequency of the RMC. Since the present study revealed a frequency of RMCs amounting to 16.12% (corresponding approximately to every sixth retromolar area), we recommend to spare it during surgery or to consider an additional locoregional anesthesia in the retromolar region. For preoperative diagnosis the CBCT has proved suitable, offering the possibility to select the spatial resolution depending on the indication, so that radiation exposure is reduced without a decrease in validity.

[CEOT - Calcified anomalies in dental X-ray. A case-based review of differential diagnoses in radiopaque lesions in maxilla and mandible]. / CEOT - Kalzifizierende Veränderungen im zahnärztlichen Röntgenbild.

The calcifying epithelial odontogenic tumor (CEOT) is a benign tumor entity, usually localized in the molar region of the lower jaw. CEOT is not known for a destructive growth pattern, nevertheless it grows expansive. To properly diagnose a CEOT, histological verification is necessary. Due to its rare appearance and low incidence (approximately 4 cases per year worldwide), it is usually not diagnosed or thought of at once. Usually it happens to be the "surprising" diagnosis after histological verification. Hereby, we represent a case report of a CEOT - also known as "pindborg" tumor, and discuss the most likely differential diagnoses.

Anatomic (positional) variation of maxillary wisdom teeth with special regard to the maxillary sinus.

The removal of wisdom teeth is one of the most common interventions in oral surgery. In order to avoid complications, a profound knowledge of the anatomy of teeth and adjacent tissues is crucial. In the case of maxillary wisdom teeth, their relationship to the maxillary sinus, to the pterygoid fossa, to the maxillary tuber and the adjacent venous plexus is particularly important. Three-dimensional (3D) imaging, for example by means of cone beam computed tomography (CBCT), is increasingly utilized in practice. However, the necessity of CBCT imaging is still a matter of intensive debate. The aim of this study was to describe the anatomic (positional) variation of maxillary wisdom teeth and, based on these findings, to elucidate the additional benefit of such imaging. A retrospective case study was performed using patients examined by means of CBCT imaging in the Department of Dento-Maxillofacial Radiology during the period from 2008 to 2013. Primary study variables comprised the spatial relationship of the teeth to the maxillary sinus, the degree of retention and root development, the covering of the root with bone and mucosa, the root configuration, and the developmental stage of the tooth. In addition, the association of the inclination of teeth in the transversal and sagittal plane with the above variables was evaluated. Descriptive statistical parameters were calculated for all results of the examination. In total, CBCT recordings of 713 maxillary wisdom teeth from 430 patients were evaluated. Their mean age was 29.8 years, and the proportion of male patients slightly prevailed (54.4%). Most teeth exhibited fully developed roots (64.1%). Overall 22.9% of third molars were impacted, 32.3% were retained, and 6.5% were erupting. In more than a third of the patients, wisdom teeth were in occlusion. The inclination of the third molars both in the transversal and sagittal plane was significantly associated with the distance of the root from the maxillary sinus as well as with the bony covering of the root. Owing to the possibility of evaluating preoperatively the relationship of a wisdom tooth to the maxillary sinus and to other anatomic structures, we recommend the use of CBCT, whenever conventional radiography fails to provide adequate information about the critical anatomic circumstances of maxillary third molars. However, CBCT should, at least nowadays, not be utilized as the standard radiographic examination.

[Preventive vaccinations in dentistry]. / Schutzimpfungen in der Zahnmedizin.

The purpose of this current paper is to give a simple update and overview about vaccinations for dental health care workers considering the new guidelines published in February 2014 by the Swiss Federal Office of Public Health. It is recommended to have at least a valid protection against hepatitis B, measles, mumps, rubella, influenza, varicella, diphtheria, tetanus, poliomyelitis and pertussis. Dental health care workers are highly exposed and high risk carriers for inoculable diseases, therefore regular refreshment of vaccinations is necessary for public health and their own health.

Lokalanästhetika - Wirkmechanismus und Risikendesalter.

A large variety of local anaesthetics is widely used in dental clinic. Cautious application is essential in order to avoid adverse events of potentially lethal nature. The objective of this article is to present an overview of the mechanisms and to underline potentially lethal adverse effects and contraindications. The knowledge of specific side effects is vital in daily practice. An overview on specific products is accessible on www.kompendium.ch, however users have to be aware of the fact that this source may be incomplete.

[Metastases in the temporomandibular joint: a review from 1954 to 2013. Rare causes for temporomandibular disorders]. / Metastasen im Kiefergelenk: Ein Literaturüberblick von 1954 bis 2013. Seltene Ursachen von Kiefergelenkbeschwerden.

INTRODUCTION: Metastatic lesions make up approximately 1% of all oral cancers.A comparatively rare location is the temporomandibular joint.Leading symptoms can be misdirecting, especially in the beginning,because they are frequently similar or even identical to those occurring in temporomandibular disorders. Therefore it can be quite difficult to confirm the diagnosis of a TMJ metastasis.delayed initiation of therapy and thus a poor prognosis are often the results. MATERIAL AND METHODS: A review of the literature from 1954 to 2013 was realized and the published cases between 1954 and January 2013 were evaluated.The results were analyzed according to gender distribution, age,first symptoms, location of the primary tumor, as well as to the occurrence of malignancies in the patients' medical history. RESULTS: The research identified sixty-six patients. Tumors of the lung and breast were the main starting points of the metastatic spread. The histopathological workup showed above all the diagnosis of an adenocarcinoma. In all of the cases, unspecific symptoms led to the diagnosis of a metastatic disease. CONCLUSION AND SIGNIFICANCE: In the case of nonspecific TMJ affection, diagnostics should consider less-frequent diagnoses, such as the presence of metastasis.A clinical differentiation by additional symptoms like swelling, unexplained weight loss and night sweats, as well as a tumor disease in the past or failure of conservative treatment can provide additional indications. If there is reasonable suspicion,extended medical imaging and diagnostic measures must be performed to allow early treatment initiation and a better prognosis.

Variations in the anatomical positioning of impacted mandibular wisdom teeth and their practical implications.

Surgical removal of impacted third molars is one of the most frequent procedures in oral surgery. Here, three-dimensional (3D) imaging is often used, yet its necessity is still being heavily debated. The aim of the study was to describe the variation in the anatomical positioning of third mandibular molars, and, by doing so, examine the necessity of 3D imaging. A retrospective case study was performed with the patients from an oral surgery department from January 2009 to February 2013. The primary focus of the study was on the spatial relationship to the mandibular canal, as well as angulation, root configuration, and developmental stage of the wisdom tooth. Descriptive statistics were calculated for these variables. A total of 1197 wisdom teeth in 699 patients were evaluated. 46.7% exhibited direct contact to the mandibular canal, another 28.7% showed close proximity and 24.6% a measurable distance. In 29.0%, the mandibular canal was vestibular and in 23.8% lingual to the wisdom tooth. In 7.4%, it was interradicular and in 0.6% intraradicular. Most teeth had one (21.3%) or two (55.3%) roots. Others had three (17.6%), four (2.0%) or five (0.2%) roots. In 31.4% of the teeth, the root perforated the lingual compact bone, and in 4.3% the vestibular compact bone. 44.4% of the teeth had mesial angulation, 9.7% distal angulation, 35.3% lingual and 2.9% buccal angulation. Due to the anatomical variety, the use of 3D imaging is recommended before surgical removal of mandibular third molars if conventional imaging cannot exclude complicated conditions.

[An atypical Stafne cavity-multi-chamber bone lesion with bucal expansion. A case report]. / Eine ungewöhnliche Stafne-Kavität. Mehrkammerige Knochenläsion mit bukkaler Auftreibung. Ein Fallbericht.

In the literature Stafne bone cavities are mostly described for male patients in their fifth and sixth decade. Usually the lingual cavities appear as ovoid lesions located unilateral in the molar region of the lower jaw underneath the inferior alveolar nerve. Classically they contain parts of the submandibular gland. This case study describes a patient who was referred to the authors’ clinic with a cavity in the right lower jaw extending over a mesio-distal diameter of 24 mm. Its appearance on panoramic x­ray and cone beam computer tomography (CTBT) was inconclusive. The diagnosis could finally be made after magnetic resonance imaging (MRI). It was based on the content of gland, fat and lymphatic tissue in a lingual open cavity, which is a characteristic feature of Stafne bone cavities. Assumed aetiology and differential diagnosis are discussed.

The inferior alveolar nerve's loop at the mental foramen and its implications for surgery.

BACKGROUND: In this study, the authors aimed to identify and measure the anterior extension of the alveolar loop (aAL) and the caudal extension of the alveolar loop (cAL) of the inferior alveolar nerve by using cone-beam computed tomography (CBCT). They also aimed to provide recommendations for surgery in the anterior mandible. METHODS: In this retrospective case study of the frequency and extension of aAL and cAL, the authors evaluated 1,384 mandibular sites in 694 CBCT scans of dentate and partly edentulous patients, performed mainly for further diagnosis before removal of the mandibular third molars between January 2009 and February 2013, by using multiplanar reconstructions. RESULTS: The frequency of aAL was 69.73 percent and of cAL was 100 percent. The mean value for aAL was 1.16 millimeters, with a range of 0.3 to 5.6 mm; the mean value for cAL was 4.11 mm, with a range of 0.25 to 8.87 mm. For aAL, 95.81 percent of the sites showed values of 0 to 3 mm; for cAL, 93.78 percent of the sites showed values of 0.25 to 6 mm. Dentate patients showed statistically significantly higher values for cAL than did partly edentulous patients (P = .043). CBCT resolution had a statistically significant impact on cAL measurements (P = .001), with higher values at higher resolution. CONCLUSIONS: This study showed a high frequency of and large variations in aAL and cAL. In contrast to panoramic radiography, CBCT has been shown to be a reliable tool for identifying and measuring the AL. Therefore, preoperative diagnosis with CBCT is recommended for planning three-dimensional tasks such as implant placement in the vicinity of the mental foramen. PRACTICAL IMPLICATIONS: Owing to the variability of aAL and cAL measurements, it is difficult to recommend reliable safety margins for surgical procedures such as implant placement, bone harvesting or genioplasty Depending on the indication, the clinician should consider preoperative diagnosis by means of CBCT.

[Modern technologies in cranio-maxillofacial surgery]. / Moderne Technologien in der Mund-, Kiefer- und Gesichtschirurgie.

Modern technologies are influencing medicine everyday. The oral and maxillofacial surgery meet the worlds from medicine and dentistry. So technologies from both fields are utilized. This article provides an overview about technologies in clinical use, which are typical for the specialty. Their principles and indications are described as well as benefits and limitations. Based on Cone Beam Computed Tomography image fusion and mirroring techniques are explained as well as patient specific models and implants, template guided and free surgical navigation with and without intraoperative three-dimensional imaging. An overall assessment reveals further need of research regarding indications and patient benefit.

Les technologies modernes influencent la médecine chaque jour. La chirurgie orale et maxillofaciale sont à disposition tant de la médecine que de la dentisterie, d'où un partage des technologies. Cet article a pour but de revoir les technologies typiques de la chirurgie orale et maxillofaciale chirurgie utilisées en clinique. Leurs principes et indications sont décrites, de même que leurs bénéfices et leurs limitations. Les scanners à faisceau conique fournissent des modèles spécifiques aux patients permettant la fabrication d'implants. Ils procurent aussi une imagerie tridimensionnelle qui peut être utile en dehors ou au cous d'une opération. Il apparaît qu'il existe encore aujourd'hui un besoin de recherche en ce qui concerne les indications de l'imagerie à faisceau conique et son bénéfice pour le malade.

Stafne bone cavities: systematic algorithm for diagnosis derived from retrospective data over a 5-year period.

Stafne bone cavities are usually found in men 50-70 years old. Typically they appear as lingual, open, ovoid lesions of the molar region of the lower jaw, and most contain parts of the submandibular gland. We have retrospectively examined panoramic radiographs acquired over a 5-year period. All lesions suspected of being Stafne bone cavities were included and analysed further to retrieve statistical information and derive a systematic diagnostic algorithm. We identified 21 Stafne bone cavities among 2928 patients (0.7%). Four of these were confirmed on cone-beam computed tomography (CT). One patient had magnetic resonance imaging (MRI) to confirm the diagnosis. The M:F ratio was 14:7 and the mean age 53 years (range 22-82). All cavities were located in the posterior mandible, 9 on the right and 12 on the left. The mean length was 10.9 (range 4.5-23) mm and height 5.7 (range 3.3-17.3) mm. All cavities were located in the posterior mandible. Sixteen panoramic radiographs (0.6%) were classified as possibly having a Stafne bone cavity but did not fulfil enough criteria to confirm the diagnosis. These 16 were not further analysed. It is rare to diagnose a Stafne bone cavity on a panoramic radiograph. Thorough investigation is essential to exclude differential diagnoses such as keratocystic odontogenic tumour, ameloblastoma, or a metastasis. In atypical presentations 3-dimensional cone-beam CT is helpful to verify the lingual opening. If the diagnosis is still not clear, it can be confirmed by MRI.

Evaluation of two dental registration-splint techniques for surgical navigation in cranio-maxillofacial surgery.

BACKGROUND: Surgical navigation requires precise registration of the pre-operative image dataset to the patient in the operation theatre. Different marker-based and marker-free registration techniques are available, each of them with advantages and disadvantages regarding precision and clinical handling. In this model study, the precision of two dental splint techniques for marker-based registration is analyzed. MATERIALS AND METHODS: A synthetic full-size human skull was registered with its cone beam computed tomography dataset using (a) a dentally-mounted "rapid" occlusal splint with five titanium screws directly attached to the splint, (b) an "extender", a dentally-mounted occlusal splint with similar fiducials fixed to an extension of the splint. The target registration error was measured for 170 landmarks distributed over the viscero- and neurocranium in 10 repeats per splint type using the Vector Vision2 (BrainLAB AG, Heimstetten, Germany) navigation system. Statistical and graphical evaluations were performed per anatomical region. RESULTS: In the periorbital region, the rapid splint, with an average deviation of 1.50 mm (SD = 0.439) showed greater accuracy than the extender with 1.76 mm (SD = 0.525). The viscerocranial results for both splints were similar (extender 1.84 mm, SD = 0.559, rapid occlusal splint 1.86 mm, SD = 0.686). In the cranial vault region, registration with the extender (2.33 mm, SD = 0.685) proved to be more precise than with the rapid splint (2.86 mm, SD = 0.929). CONCLUSIONS: Due to the more compact dimension of the rapid occlusal splint, errors close to the splint were smaller compared to the extender technique. The advantage of greater distances between the registration fiducials on the extender is particularly important in areas such as the orbital roof, the cranial vault, and the lateral skull base.

[Facial pain- a rare cause. Impacted lower third molars causing primarily "unclear" facial pain: a case report]. / Gesichtsschmerzen - eine seltene Ursache. Retinierte untere Weisheitszahne als Ursache fur zunachst <> Gesichtsschmerzen. Ein Fallbericht.

Orofacial pain often causes special difficulties to patients and dentists. Numerous differential diagnoses require the utilization of a coordinated diagnostic concept. Often, multiple causes lead to the need for a complex treatment plan. Impacted third molars are a potential cause of a variety of complications. Caries, pulp necrosis, and periapical infection are some of the infrequent causes of such pain. The presented case shows just such a constellation, resulting in primarily "unclear" orofacial pain. A diagnostic sequence generally leads to the correct diagnosis and thereby allows for fast and effective therapy. This shows how important structured diagnostics are, especially in cases of "unclear" pain.

Demodicidosis: an uncommon erythema after cranio-maxillofacial surgery.

Demodex mites are commonly found in the healthy population, but the pathogenesis of demodicidosis has still not been clarified, though it is usually found in cases of immune deficiency. A 45-year-old man presented with an unusual outbreak of erythema and swelling 6 months after resection and chemoradiotherapy for a squamous cell carcinoma of the anterior floor of the mouth. The cheek was biopsied and histological examination showed demodicidosis. In cases of erythema with a normal blood cell count and no history of allergy, particularly in patients with reduced immunity, demodicidosis should be considered as a diagnosis and should be confirmed by examination of a biopsy specimen.

Growing skull fractures after craniosynostosis repair: risk factors and treatment algorithm.

Growing skull fractures (GSFs) are rare complications after severe head injuries in the early childhood and rarely occur after craniosynostosis repair. The aim of this study was to define an algorithm for sufficient treatment for GSF after craniofacial procedures. Literature research was performed to clarify risk factors for GSFs after cranial vault reshaping. Conclusions of the literature and experiences of the authors based on a case of GSF after craniofacial surgery were matched to establish guidelines for successful therapy.

The Reliability of a Three-Dimensional Photo System- (3dMDface-) Based Evaluation of the Face in Cleft Lip Infants.

Ample data exists about the high precision of three-dimensional (3D) scanning devices and their data acquisition of the facial surface. However, a question remains regarding which facial landmarks are reliable if identified in 3D images taken under clinical circumstances. Sources of error to be addressed could be technical, user dependent, or patient respectively anatomy related. Based on clinical 3D photos taken with the 3dMDface system, the intra observer repeatability of 27 facial landmarks in six cleft lip (CL) infants and one non-CL infant was evaluated based on a total of over 1,100 measurements. Data acquisition was sometimes challenging but successful in all patients. The mean error was 0.86 mm, with a range of 0.39 mm (Exocanthion) to 2.21 mm (soft gonion). Typically, landmarks provided a small mean error but still showed quite a high variance in measurements, for example, exocanthion from 0.04 mm to 0.93 mm. Vice versa, relatively imprecise landmarks still provide accurate data regarding specific spatial planes. One must be aware of the fact that the degree of precision is dependent on landmarks and spatial planes in question. In clinical investigations, the degree of reliability for landmarks evaluated should be taken into account. Additional reliability can be achieved via multiple measuring.