Poliklinik für Zahnärztliche Prothetik

Abstract In der Übergangsmetallchemie gibt es eine Klasse von Komplexverbindungen, bei denen eine Temperaturerniedrigung einen Wechsel im Spinzustand des Zentralatoms vom High‐Spin‐ in den Low‐Spin‐Zustand bewirkt. Dabei ändern sich die magnetischen und optischen Eigenschaften, über die der thermische Spinübergang (auch Spincrossover genannt) sehr gut verfolgt werden kann. Dieses Phänomen tritt sowohl in flüssiger Phase als auch im Festkörper auf. Eine herausragende Stellung nehmen Eisen(II) — Spincrossover — Verbindungen ein, in denen der Spinübergang im Festkörper auf sehr unterschiedliche Weise — graduell, abrupt, mit Hysterese oder stufenweise — verlaufen kann und mit Mößbauer‐ und optischer Spektroskopie, mit magnetischen Suszeptibilitäts‐ und Wärmekapazitätsmessungen sowie durch Kristallstrukturanalyse intensiv untersucht worden ist. Die kooperative Wechselwirkung zwischen den einzelnen Komplexmolekülen kann befriedigend durch elastische Eigenschaften und durch die Änderung von Gestalt und Volumen der Komplexmoleküle beim Spinübergang erklärt werden. Bei Untersuchungen an Eisen(II)‐Spincrossover‐Verbindungen konnte man beobachten, daß sich der Low‐Spin‐Zustand mit grünem Licht in den High‐Spin‐Zustand umschalten läßt, der bei tiefen Temperaturen eine nahezu unendlich lange Lebensdauer haben kann (LIESST = Light‐Induced Excited Spin State Trapping). Mit rotem Licht läßt sich der metastabile High‐Spin‐ wieder in den Low‐Spin‐Zustand zurückschalten. Der Mechanismus des LIESST‐Effekts ist aufgeklärt, die Zerfallskinetik im Detail untersucht und im Rahmen der Theorie strahlungsloser Übergänge verstanden. Anwendungen des LIESST‐Effekts in der optischen Informationstechnik sind denkbar.

We report four new cases of oral manifestation in Crohn's disease (CD) and evaluate 75 reported cases for morphology and site of oral and intestinal manifestations of CD, clinical manifestation, and treatment. Oral CD was the presenting symptom in 43 of 72 (60%) patients and relapsed in 34 of 60 (57%). Median age at presentation was 22 (range 6-57) years, and males were affected more often (1.85:1, male:female ratio). From a total of 228 oral lesions in 79 patients, lips (57 lesions), gingiva (40 lesions), vestibular sulci (31 lesions), and buccal mucosa (25 lesions) were the sites most frequently affected. Edema (62 lesions), ulcers (57 lesions), and polypoid papulous hyperplastic mucosa (45 lesions) were the most common type of lesions. The rate of granuloma detection was high in oral (67-77%) and intestinal lesions (45-71%). A total of 66 courses of drug therapy in 51 patients were analyzed. Complete remission of oral symptoms was achieved by systemic steroids and/or azathioprine in 13 of 26 (50%) patients, whereas strictly topical treatment with steroids resulted in complete remission of oral symptoms in 7 of 12 (58%). We conclude that oral CD exhibits a characteristic morphologic appearance, as often as not preceding intestinal symptoms in adolescents and young adults. Thus, patients with orofacial granulomatosis CD should be vigorously searched for by complete gastrointestinal endoscopic investigation. Oral CD may cause disabling pain and facial distortion, and results of treatment remain unrewarding. In the absence of data from controlled therapeutic trials, systemic steroids and/or azathioprine are recommended if topical treatment has failed to control symptoms.

Biofabrication is an emerging and rapidly expanding field of research in which additive manufacturing techniques in combination with cell printing are exploited to generate hierarchical tissue-like structures. Materials that combine printability with cytocompatibility, so called bioinks, are currently the biggest bottleneck. Since recombinant spider silk proteins are non-immunogenic, cytocompatible, and exhibit physical crosslinking, their potential as a new bioink system was evaluated. Cell-loaded spider silk constructs can be printed by robotic dispensing without the need for crosslinking additives or thickeners for mechanical stabilization. Cells are able to adhere and proliferate with good viability over at least one week in such spider silk scaffolds. Introduction of a cell-binding motif to the spider silk protein further enables fine-tuned control over cell-material interactions. Spider silk hydrogels are thus a highly attractive novel bioink for biofabrication.

In recent years the management of human immunodeficiency virus (HIV)-positive individuals has been based on highly active antiretroviral therapy (HAART) comprising a combination of nucleoside analogues or the combination of these agents with protease inhibitors. The aim of the present study was to describe the prevalence of oral lesions in a cohort of 103 HIV-seropositive patients on HAART, to compare these data with the prevalence of lesions prior to HAART and to correlate these finding with the immunologic data. A total of 103 HIV-seropositive patients on HAART were selected. Oral lesions associated with HIV infection and immunological parameters were registered. On re-examination 6 months after the first evaluation, 61/103 patients were available. Comparing the prevalence of oral lesions before and after the onset of HAART, the number of oral lesions was significantly lower (P=0.001). The number of CD4+ cells increased and the viral load decreased significantly after initiation of HAART (P=0.001 and P= 0.0001). On re-examination 6 months later, the prevalence of lesions again decreased significantly (P=0.001). The immunological benefits of HAART may prevent HIV-associated oral lesions in patients with advanced HIV disease. Our results showed that oral manifestations decrease on HAART, but in four patients the immunological effects of therapy did not provide sufficient protection against human papillomavirus (HPV)induced lesions.

CONTEXT: The Patient Protection and Affordable Care Act's (PPACA) emphasis on community-based initiatives affords a unique opportunity to disseminate and scale up evidence-based community health worker (CHW) models that integrate CHWs within health care delivery teams and programs. Community health workers have unique access and local knowledge that can inform program development and evaluation, improve service delivery and care coordination, and expand health care access. As a member of the PPACA-defined health care workforce, CHWs have the potential to positively impact numerous programs and reduce costs. OBJECTIVE: This article discusses different strategies for integrating CHW models within PPACA implementation through facilitated enrollment strategies, patient-centered medical homes, coordination and expansion of health information technology (HIT) efforts, and also discusses payment options for such integration. RESULTS: Title V of the PPACA outlines a plan to improve access to and delivery of health care services for all individuals, particularly low-income, underserved, uninsured, minority, health disparity, and rural populations. Community health workers' role as trusted community leaders can facilitate accurate data collection, program enrollment, and provision of culturally and linguistically appropriate, patient- and family-centered care. Because CHWs already support disease management and care coordination services, they will be critical to delivering and expanding patient-centered medical homes and Health Home services, especially for communities that suffer disproportionately from multiple chronic diseases. Community health workers' unique expertise in conducting outreach make them well positioned to help enroll people in Medicaid or insurance offered by Health Benefit Exchanges. New payment models provide opportunities to fund and sustain CHWs. CONCLUSION: Community health workers can support the effective implementation of PPACA if the capacity and potential of CHWs to serve as cultural brokers and bridges among medically underserved communities and health care delivery systems is fully tapped. Patient Protection and Affordable Care Act and current payment structures provide an unprecedented and important vehicle for integrating and sustaining CHWs as part of these new delivery and enrollment models.

Dieser Buchtitel ist Teil des Digitalisierungsprojekts Springer Book Archives mit Publikationen, die seit den Anfängen des Verlags von 1842 erschienen sind. Der Verlag stellt mit diesem Archiv Quellen

BACKGROUND: It is recommended that botulinum toxin be used immediately or within 2 weeks after its reconstitution because its efficacy might be compromised by prolonged storage. OBJECTIVES: To evaluate the efficacy of botulinum toxin type A (BTX-A) reconstituted over 6 consecutive weeks for the treatment of glabellar frown lines. METHODS: Four vials of BTX-A were reconstituted each of 7 days over a period of 6 weeks, totaling 28 vials, corresponding to seven reconstitution dates. During this period, the BTX-A was stored according to the manufacturer's instructions. On the day after the last reconstitution, all of the reconstituted vials were injected in patients from four dermatologic centers taking part in this study. A total of 88 patients were treated on the same day and were followed every 2 weeks for 4 months. All patients were photographed at all stages. A number of professionals assessed the efficacy of reconstituted BTX-A based on the reduction of the maximum frowning capacity of the treated muscles. RESULTS: Of the 88 patients who were selected, 3 were excluded. Three forms of evaluation were applied, and no statistically significant differences were found in the results presented. CONCLUSION: BTX-A may be applied up to 6 weeks after reconstitution without losing its effectiveness. Other factors, which are probably individual, may influence the response to BTX-A injections.

An apparatus for the study of three-dimensional force systems and the resulting movements during orthodontic treatment is presented. The instrument consists of two force-torque transducers which are capable of recording both forces and torques simultaneously, in all spatial directions. Each sensor has a measuring range of 15N (450 Nmm) and a resolution of 0.02 N (0.5 Nmm) and is mounted on a set of three translational and three rotational stages driven by stepping motors. Positioning accuracy is in the range of 1 micron and 0.01 degrees respectively. The apparatus is computer controlled and supported by comprehensive software.

Dieser Buchtitel ist Teil des Digitalisierungsprojekts Springer Book Archives mit Publikationen, die seit den Anfängen des Verlags von 1842 erschienen sind. Der Verlag stellt mit diesem Archiv Quellen

Classification of odontogenic tumours is an academic exercise that has developed over the last 150 years. It was not until 1971 when a 5-year collaborated effort, organized by the World Health Organization (WHO), resulted in the first consensus on taxonomy of odontogenic tumours. The appearance of this first authoritative guide to the classification of odontogenic tumours marked the start of an era of quite intensive interest for studying this particular field of oral pathology. An updated 2nd edition of the WHO classification was published in 1992.

Systemic diseases affecting the host response as primary immunodeficiencies or secondary defects caused by lack of nutrients or changes in the local tissues are very often accompanied by early-onset prepubertal periodontitis. Local treatment in combination with systemic antibiotics may in milder forms improve the situation, but in many cases the success is questionable and premature loss of teeth occurs. Since the genetic basis of many of the diseases has been identified, future developments permit the correction of at least some of these defects by gene therapy.

BACKGROUND: Previous studies found that stress, depression, burnout, anxiety, and depersonalisation play a significant role amongst dental and medical students. We wanted to examine if students of the University of Erlangen-Nuremberg also would report elevated values as can been found in similar publications. Furthermore, particularly coping strategies were investigated. METHODS: The data collection took place in April 2008 including 182 dental and medical students of the 4th and 5th academic year at the University of Erlangen-Nuremberg. Demographic data and the following screening instruments were used: Maslach Burnout Inventory (MBI), Cambridge Depersonalisation Scale (CDS-9), Hospital Anxiety and Depression Scale (HADS), Brief COPE. RESULTS: Descriptive statistics showed higher pathological values in dental students than in medical students. The difference was especially pronounced on the depersonalisation scale (CDS-9), with 20.4% of the dental students, but only 5.5% of the medical students showing scores above a cut-off of 19. The scores decreased in the course of 3 semesters of dentistry. The students with elevated values showed a higher degree of dysfunctional coping. CONCLUSION: Our results obtained with the screening instruments are in line with the results of previous investigations of other authors and point out the importance of this issue. It might be useful to develop programs teaching dental students more adaptive coping strategies before their first patient contact.

The groups A1 to C3 of the "group classification of partially edentulous arches" by Eichner are characterized by the number of teeth and the topography of the natural dentition. This could be demonstrated in a clinical study on 1000 patients prepared by Blume-Gréger. The result shows a percentage of 49.5 in the groups A, 22.4% in the B-groups and 28.1% in the C-groups. Furthermore, these groups represent the course of tooth loss also regarding the functional value of the natural dentition. Thus, this classification provides a standard for the degree of morbidity of the dentition and is suitable for application in studies on morbidity statistics. When used for documentation files there is an error possibility of 1.9%.

The contact between tissue and the implanted biomaterial is influenced by the micromorphology of the implant surface as well as biomechanical reactions. This effect is mediated by subcellular morphological structures and can affect the anchorage of the material inside the body of the host. The aim of the present study was to ascertain by transmission electron microscopy how human gingival fibroblasts interact with surface events. A special replica technique was used to produce a line pattern of 1 micron pitch with a depth of 1 micron. It was demonstrated, by transmission electron microscopy, that cells seeded on this surface extended cellular processes into the grooves, leading to an intensive contact and probably to mechanical interlocking. The typical morphological structures at several points indicated the presence of focal adhesion sites.

The Periotest is a new instrument for the diagnosis of periodontal diseases. The 'Periotest value' depends to some extent on tooth mobility, but mainly on the damping characteristics of the periodontium. The Periotest measures the reaction to a reproducible impact applied to the tooth crown. The Periotest value is a biophysical parameter.

This article describes the development and testing of a computer-controlled chewing simulator which is able to simulate the wear mechanisms and temperature changes that can occur in the mouth. It was further evaluated if the opposing cusps used in this chewing simulator should be metallic or if natural enamel was preferential. The results indicated that the machine fulfilled the parameters concerning chewing motion and thermal changes reported in the literature. Furthermore it was shown that natural enamel cusps must be used as the opposing dentition. The chewing simulator will form a part of an in-vitro test, which will allow the evaluation of dental restorative systems under clinically relevant conditions.

Abstract Die Stickstoff‐Abspaltung aus organischen Molekülen kann zu reaktionsfähigen, ungeladenen Zwischenstufen mit Elektronensextett führen, zu Derivaten des Methylens ∣CH 2 oder des Imins ∣ N H. Andere Bildungsweisen dieser Zwischenstufen werden zum Vergleich herangezogen. Ihre Reaktionen in Abhängigkeit von Struktur und Entstehung werden besprochen, wobei präparativ verwertbare Umsetzungen im Vordergrund stehen.

Sinus augmentation has been advocated to be a surgical technique with predictable results in peri-implant surgery. Endoscopic surgery of the maxillary sinus so far has been used as diagnostic procedure. In this paper, the use of endoscopy is described as a low invasive adjunctive technique in sinus floor augmentation. After preparation of the mucoperiosteum, bone grafts can be placed under endoscopic control between sinus floor and mucoperiosteum. A laterobasal approach via a small osteotomy and a transalveolar approach are possible for mucosal elevation and graft placement. First clinical results are reported. Endoscopic sinus lift may contribute to a reduction of perioperative morbidity, reduction of oroantral fistulae and control of graft position. The less invasive technique may allow to extend the indication for sinus augmentation.

This paper compares the morphology and function of the natural periodontium with peri-implant tissues and tissue reactions. The comparison serves as a base for observations about the practical application of oral endosseous implants. The main conclusion is that the touch sensitivity of natural teeth at lower biting and chewing loads, that is in the phase of primary tooth mobility, during which only the soft parts of the periodontium are deformed, cannot be substituted by ankylotic retained implants.

BACKGROUND: Serum lipoprotein(a) [Lp(a)] concentration is largely determined by variability at the apolipoprotein(a) gene locus. Most prominent effects relate to polymorphisms in the promoter (a pentanucleotide [PN] repeat) and coding regions (a kringle IV [K4] repeat), the latter of which also affects Lp(a) particle size. The impact of these polymorphisms on cardiovascular risk is poorly understood. METHODS AND RESULTS: We studied both polymorphisms and Lp(a) levels in 834 registry-based myocardial infarction (MI) patients (38% women) and 1548 population-based controls. Lp(a) concentrations were inversely related with the numbers of K4 and PN repeats. However, the effect of the PN polymorphism was restricted to subjects producing small Lp(a) particles (<or=8 PN 66.1 mg/dL versus >8 PN 8.7 mg/dL; P<0.0001). The odds to present with MI were elevated in individuals producing small Lp(a) particles (<or=22 K4 repeats; OR 1.47 for men and 1.69 for women; P<0.002) and in women with <or=8 PN repeats (OR 1.46, P=0.009). Interestingly, in women, the frequent haplotype with <or=8 PN and <or=22 K4 repeats, which is related to high levels of small Lp(a) particles, resulted in an elevated OR for MI (1.79; P=0.01) independently of Lp(a) serum concentration. CONCLUSIONS: The K4 and PN repeat polymorphisms largely explain the high variability of serum Lp(a) levels. A haplotype with <or=8 PN and <or=22 K4 repeats is characterized by high concentrations of small Lp(a) particles. Our observation that this haplotype was associated with MI independently of Lp(a) serum levels may suggest that Lp(a) particle size in addition to its concentration may modulate MI risk in women.