Einsatz von patientenspezifischen Implantaten – eine Übersicht und aktuelle Entwicklungen

Der Begriff der personalisierten Medizin wird im 21. Jahrhundert zum Fokus einer modernen Patientenversorgung. Im Bereich der rekonstruktiven Mund‑, Kiefer- und Gesichtschirurgie sind patientenspezifische Implantate (PSI) zentraler Bestandteil einer personalisierten Medizin. Dank des Einsatzes computerunterstützter Gestaltung und Fertigung (CAD/CAM) können auch komplexe anatomische Defekte präzise, vorhersagbar und individuell rekonstruiert werden. Operationssimulationen können dem Patienten das Therapieziel inklusive therapiebedingter ästhetischer Veränderungen aufzeigen und damit neben der Personalisierung auch eine verbesserte Partizipation an der Therapieentscheidung herbeiführen. Frühere Spezialindikationen werden zum Therapiestandard und die Anwendung der PSI konnte auf weitere Spezialgebiete innerhalb der MKG-Chirurgie ausgeweitet werden. Optimierte Planungs- und Herstellungsabläufe unter dem Einsatz von künstlicher Intelligenz, Visualisierung und intraoperative Unterstützung des Chirurgen durch Augmented Reality (AR) sowie der Einsatz neuer dreidimensional druckbarer Biomaterialien sind Bestandteile der aktuellen Forschung und werden das Indikationsspektrum für PSI in Zukunft nochmals erweitern können. // The concept of personalized medicine is becoming the focus of modern patient care. In the field of reconstructive oral and maxillofacial surgery, patient-specific implants (PSI) are a central component of personalized medicine. Thanks to the use of computer-aided design and manufacturing (CAD/CAM) processes, even complex anatomical defects can be reconstructed precisely, predictably, and individually. Surgical simulations can show the patient the treatment goal including treatment-related aesthetic changes and, thus, in addition to personalization, also improve participation in the treatment decision. Former special indications are becoming the therapeutic standard and the application of PSI could be expanded to further specialties within oral and maxillofacial surgery. Optimized planning and manufacturing processes using artificial intelligence (AI), visualization, and intraoperative support of the surgeon through augmented reality (AR) as well as the use of new 3D printable biomaterials are components of current research and will expand the range of indications for PSI further in the future

Visualization of Inferior Alveolar and Lingual Nerve Pathology by 3D Double-Echo Steady-State MRI: Two Case Reports with Literature Review

Injury to the peripheral branches of the trigeminal nerve, particularly the lingual nerve (LN) and the inferior alveolar nerve (IAN), is a rare but serious complication that can occur during oral and maxillofacial surgery. Mandibular third molar surgery, one of the most common surgical procedures in dentistry, is most often associated with such a nerve injury. Proper preoperative radiologic assessment is hence key to avoiding neurosensory dysfunction. In addition to the well-established conventional X-ray-based imaging modalities, such as panoramic radiography and cone-beam computed tomography, radiation-free magnetic resonance imaging (MRI) with the recently introduced black-bone MRI sequences offers the possibility to simultaneously visualize osseous structures and neural tissue in the oral cavity with high spatial resolution and excellent soft-tissue contrast. Fortunately, most LN and IAN injuries recover spontaneously within six months. However, permanent damage may cause significant loss of quality of life for affected patients. Therefore, therapy should be initiated early in indicated cases, despite the inconsistency in the literature regarding the therapeutic time window. In this report, we present the visualization of two cases of nerve pathology using 3D double-echo steady-state MRI and evaluate evidence-based decision-making for iatrogenic nerve injury regarding a wait-and-see strategy, conservative drug treatment, or surgical re-intervention

Increase in periosteal angiogenesis through heat shock conditioning

<p>Abstract</p> <p>Objective</p> <p>It is widely known that stress conditioning can protect microcirculation and induce the release of vasoactive factors for a period of several hours. Little, however, is known about the long-term effects of stress conditioning on microcirculation, especially on the microcirculation of the periosteum of the calvaria. For this reason, we used intravital fluorescence microscopy to investigate the effects of heat shock priming on the microcirculation of the periosteum over a period of several days.</p> <p>Methods</p> <p>Fifty-two Lewis rats were randomized into eight groups. Six groups underwent heat shock priming of the periosteum of the calvaria at 42.5°C, two of them (n = 8) for 15 minutes, two (n = 8) for 25 minutes and two (n = 8) for 35 minutes. After 24 hours, a periosteal chamber was implanted into the heads of the animals of one of each of the two groups mentioned above. Microcirculation and inflammatory responses were studied repeatedly over a period of 14 days using intravital fluorescence microscopy. The expression of heat shock protein (HSP) 70 was examined by immunohistochemistry in three further groups 24 hours after a 15-minute (n = 5), a 25-minute (n = 5) or a 35-minute (n = 5) heat shock treatment. Two groups that did not undergo priming were used as controls. One control group (n = 8) was investigated by intravital microscopy and the other (n = 5) by immunohistochemistry.</p> <p>Results</p> <p>During the entire observation period of 14 days, the periosteal chambers revealed physiological microcirculation of the periosteum of the calvaria without perfusion failures. A significant (p < 0.05) and continuous increase in functional capillary density was noted from day 5 to day 14 after 25-minute heat shock priming. Whereas a 15-minute exposure did not lead to an increase in functional capillary density, 35-minute priming caused a significant but reversible perfusion failure in capillaries. Non-perfused capillaries in the 35-minute treatment group were reperfused by day 10. Immunohistochemistry demonstrated an increase in cytoprotective HSP70 expression in the periosteum after a 15-minute and a 35-minute heat shock pretreatment when compared with the control group. The level of HSP70 expression that was measured in the periosteum after 25 minutes of treatment was significantly higher than the levels observed after 15 or 35 minutes of heat shock exposure.</p> <p>Conclusion</p> <p>A few days after heat shock priming over an appropriate period of time, a continuous increase in functional capillary density is seen in the periosteum of the calvaria. This increase in perfusion appears to be the result of the induction of angiogenesis.</p

Virtual 3D tumor marking-exact intraoperative coordinate mapping improve post-operative radiotherapy

The quality of the interdisciplinary interface in oncological treatment between surgery, pathology and radiotherapy is mainly dependent on reliable anatomical three-dimensional (3D) allocation of specimen and their context sensitive interpretation which defines further treatment protocols. Computer-assisted preoperative planning (CAPP) allows for outlining macroscopical tumor size and margins. A new technique facilitates the 3D virtual marking and mapping of frozen sections and resection margins or important surgical intraoperative information. These data could be stored in DICOM format (Digital Imaging and Communication in Medicine) in terms of augmented reality and transferred to communicate patient's specific tumor information (invasion to vessels and nerves, non-resectable tumor) to oncologists, radiotherapists and pathologists

Dark sectors 2016 Workshop: community report

This report, based on the Dark Sectors workshop at SLAC in April 2016, summarizes the scientific importance of searches for dark sector dark matter and forces at masses beneath the weak-scale, the status of this broad international field, the important milestones motivating future exploration, and promising experimental opportunities to reach these milestones over the next 5-10 years

3D-Cinematic rendering for dental and maxillofacial imaging

OBJECTIVES Aim of this technical note is to show the applicability of cinematic rendering (CR) for a photorealistic 3-dimensional (3D) visualization of maxillofacial structures. The focus is on maxillofacial hard tissue pathologies. METHODS High density maxillofacial pathologies were selected in which CR is applicable. Data from both, computed tomography (CT) and cone beam computed tomography (CBCT) were postprocessed using a prototype CR software. RESULTS CR 3D postprocessing of CT and CBCT imaging data is applicable on high density structures and pathologies such as bones, teeth, and tissue calcifications. Image reconstruction allows for a detailed visualization of surface structures, their plasticity, and 3D configuration. CONCLUSIONS CR allows for the generation of photorealistic 3D reconstructions of high density structures and pathologies. Potential applications for maxillofacial bone and tooth imaging are given and examples for CT and CBCT images are displayed