TY - THES A1 - Hespelt, Christoph Reiner T1 - Tierexperimentelle Studie über den Einfluss hyperbaren Sauerstoffs auf das Knochenneuwachstum in Knochendefekten "kritischer Größe" T1 - The influence of hyperbaric oxygen on new bone formation in critical size bone defects. An experimental study in rats N2 - In der modernen Zahnmedizin stellen rekonstruktive Maßnahmen große Anforderungen an den Behandler. Verlorengegangener Alveolarknochen kann mit der geführten Knochenregeneration wieder aufgebaut und sogar vermehrt werden. Dieses Verfahren hat sich als sogenannter „Goldstandard“ etabliert. In der Medizin gehört die Anwendung hyperbaren Sauerstoffs bei ausgewählten Krankheitsbildern mittlerweile zum Standard. Aufgrund seiner positiven Eigenschaften auf die Neoangiogenese, Sauerstoffdiffusion und seiner bakteriziden Wirkung wird das Behandlungsergebnis teilweise erheblich verbessert oder eine Therapie dadurch erst möglich. Ziel der vorliegenden Arbeit war, quantitative Aussagen darüber zu treffen, ob die Kombination aus geführter Knochenregeneration mit nichtresorbierbaren Membranen aus expandiertem Polytetrafluorethylen und der Anwendung hyperbaren Sauerstoffs das Knochenneuwachstum signifikant beeinflusst. Dazu wurde ein Modell mit 40 Albino Sprague-Dawley Ratten, unterteilt in 4 Gruppen à 10 Tieren, gewählt, um nach einer Versuchsdauer von 14 Tagen anhand angefertigter histologischer Schnittbilder Neuknochen histometrisch zu bestimmen und zu vergleichen. Untersuchungsparameter waren die Neuknochenlänge und Neuknochenfläche. Die statistische Auswertung der ermittelten Daten bestätigte die Überlegenheit membrangeführter Knochenregeneration (Gruppe 4) im Vergleich zur rein schleimhaut- und periostgedeckten Defektbehandlung (Gruppe 3). Zahlreiche Untersuchungen dazu liegen in der Literatur vor. Die zusätzliche Anwendung von hyperbarem Sauerstoff ergab keine signifikante Verbesserung der Ergebnisse. Im Gegenteil zeigte sich eine tendenzielle Verschlechterung, was die Signifikanzen beim statistischen Vergleich der Gruppen 2 und 4 belegen. In diesem Modell konnte nicht gezeigt werden, dass die vielen positiven Eigenschaften des hyperbaren Sauerstoffs auf den Knochen für Knochendefekte „kritischer Größe“ begünstigend und verbessernd anwendbar sind. N2 - In modern dentistry the regeneration of lost hard tissues still requires high skills. Reconstruction of deficient alveolar ridges using guided bone regeneration is possible and considered the “gold standard”. Hyperbaric oxygen therapy (HBOT) is standard in certain diseases since its positive effects on angiogenesis and oxygen diffusion and its antibacterial effect allows for better wound healing results. It was the aim of this study to investigate the influence of hyperbaric oxygen therapy and guided bone regeneration with expanded non-absorbable polytetrafluoroethylene membranes on the formation of new bone. Forty albino sprague-dawley rats, divided in 4 groups, were used for this investigation. After a period of 14 days new bone formation was histologically described and histomorphometrically assessed. The use of a membrane (group 4) revealed significantly better results when compared soft tissue coverage only (group 3) However, no significant advantages could be demonstrated upon application of hyperbaric oxygen with or without the use of a membrane (groups 2 and 4). On the contrary, there was a tendency towards worse regenerative results. The various positive effects of hyperbaric oxygen therapy on bone tissue could not be demonstrates in defects of “critical size” in this rat model. KW - Knochenregeneration KW - hyperbarer Sauerstoff KW - Knochendefekte kritischer Größe KW - Membranen KW - ePTFE KW - Rattenmodell KW - histologisch KW - histometrisch KW - guided bone regeneration KW - hyperbaric oxygen KW - critical size bone defects KW - membranes KW - ePTFE KW - histologic KW - histometric Y1 - 2010 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-48977 ER - TY - JOUR A1 - Fuchs, A. A1 - Youssef, A. A1 - Seher, A. A1 - Hochleitner, G. A1 - Dalton, P. D. A1 - Hartmann, S. A1 - Brands, R. C. A1 - Müller-Richter, U. D. A. A1 - Linz, C, T1 - Medical-grade polycaprolactone scaffolds made by melt electrospinning writing for oral bone regeneration – a pilot study in vitro JF - BMC Oral Health N2 - Background The spectrum of indications for the use of membranes and scaffolds in the field of oral and maxillofacial surgery includes, amongst others, guided bone regeneration (GBR). Currently available membrane systems face certain disadvantages such as difficult clinical handling, inconsistent degradation, undirected cell growth and a lack of stability that often complicate their application. Therefore, new membranes which can overcome these issues are of great interest in this field. Methods In this pilot study, we investigated polycaprolactone (PCL) scaffolds intended to enhance oral wound healing by means of melt electrospinning writing (MEW), which allowed for three-dimensional (3D) printing of micron scale fibers and very exact fiber placement. A singular set of box-shaped scaffolds of different sizes consisting of medical-grade PCL was examined and the scaffolds’ morphology was evaluated via scanning electron microscopy (SEM). Each prototype sample with box sizes of 225 μm, 300 μm, 375 μm, 450 μm and 500 μm was assessed for cytotoxicity and cell growth by seeding each scaffold with human osteoblast-like cell line MG63. Results All scaffolds demonstrated good cytocompatibility according to cell viability, protein concentration, and cell number. SEM analysis revealed an exact fiber placement of the MEW scaffolds and the growth of viable MG63 cells on them. For the examined box-shaped scaffolds with pore sizes between 225 μm and 500 μm, a preferred box size for initial osteoblast attachment could not be found. Conclusions These well-defined 3D scaffolds consisting of medical-grade materials optimized for cell attachment and cell growth hold the key to a promising new approach in GBR in oral and maxillofacial surgery. KW - melt electrospinning writing KW - polycaprolactone KW - scaffold KW - guided bone regeneration Y1 - 2019 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-200274 VL - 19 ER - TY - JOUR A1 - Fickl, Stefan A1 - Therese Kröger, Annika A1 - Dietrich, Thomas A1 - Kebschull, Moritz T1 - Influence of soft tissue augmentation procedures around dental implants on marginal bone level changes-A systematic review JF - Clinical Oral Implants Research N2 - Objectives This systematic review assessed the influence of soft tissue augmentation procedures on marginal bone level changes in partial or fully edentulous patients. Material and Methods We identified three relevant PICO questions related to soft tissue augmentation procedures and conducted a systematic search of four major electronic databases for clinical studies in systemically healthy patients receiving at least one dental implant and a minimum follow-up of one year after implant placement. The primary outcome was mean difference in marginal bone levels, and secondary outcomes were clinical and patient-related outcomes such as thickness of peri-implant mucosa, bleeding indices, and Pink Esthetic Score. Results We identified 20 publications reporting on 16 relevant comparisons. Studies varied considerably and thus only two meta-analyses could be performed. This systematic review showed that: Soft tissue augmentation either for augmentation of keratinized mucosa or soft tissue volume inconsistently had an effect on marginal bone level changes when compared to no soft tissue augmentation, but consistently improved secondary outcomes. The combination soft and hard tissue augmentation showed no statistically significant difference in terms of marginal bone level changes when compared to hard tissue augmentation alone, but resulted in less marginal soft tissue recession as shown by a meta-analysis. Soft or hard tissue augmentation performed as contour augmentations resulted in comparable marginal bone level changes. Conclusions Peri-implant soft and hard tissues seem to have a bidirectional relationship: “Bone stands hard, but soft tissue is the guard”. KW - soft tissue augmentation KW - alveolar ridge augmentation KW - bone augmentation KW - dental implants KW - guided bone regeneration KW - guided tissue regeneration Y1 - 2021 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-258394 VL - 32 IS - S21 ER -