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Background: The use of microvascular grafts is the gold standard in oral and maxillofacial surgery for the reconstruction of soft tissue and bony and combined defects. Graft loss is one of the most serious complications in the field of reconstructive surgery. A comprehensive analysis of factors influencing this is, therefore, essential. Methods: This hypothesis-generating study analyzed 251 patient cases of oral and maxillofacial surgery at the University Hospital Düsseldorf from 2016 to 2020 regarding patient- and therapy-specific parameters for their impact on graft survival. Results: Statistically significant influencing factors were found among the 80 parameters examined: treatment with antiplatelet medication and a BMI ≥ 24.5 at the time of surgery had a positive influence on graft survival, while existing diabetes mellitus, atrial fibrillation, tracheostomy, and a longer operation time had a statistically relevant negative influence. Conclusions: This work demonstrates the relevance of patient-specific risk stratification and the need for further research to develop a valid risk profile. Identifying high-risk patients with medium-sized defects, where alternatives to microvascular reconstruction are available, appears to be crucial for the clinical outcome. [ABSTRACT FROM AUTHOR]

Background/Objectives: In oral and maxillofacial surgery, the reconstruction of defects often involves the transfer of skin tissue into the oral cavity utilizing microvascular grafts. This study investigates postoperative changes in microbial colonization following intraoral microvascular transplantation, as well as potential influencing factors. Methods: In 37 patients undergoing intraoral reconstructions, pre- and postoperative swabs were taken from the donor and recipient regions to quantify the seven selected marker bacteria using TaqMan PCRs. Patient-specific factors and clinical data were also recorded. Results: The infection-associated Acinetobacter baumannii tended to decrease postoperatively, while the infectious pathogens Pseudomonas aeruginosa, Enterococcus faecalis and the family of Enterobacteriaceae showed a postoperative increase without being directly associated with a clinical infection. Streptococcus mitis showed a significant postoperative decrease on buccal mucosa and increase on the graft surface (oral dysbiosis) and was significantly reduced or displaced by other bacteria (e.g., Mycoplasma salivarium, positive selection) when treated with ampicillin/sulbactam. Conclusions: The cutaneous microbiome of the graft adapts to the local intraoral environment. Postoperative shifts in oral bacterial colonization and an increase in infection-relevant bacteria were observed. These perioperative changes in colonization are also influenced by the administration of ampicillin/sulbactam. Consequently, single doses of antibiotics appear to be more beneficial compared to longer-term preventive use. [ABSTRACT FROM AUTHOR]

Titanium continues to be the gold standard in the field of osteosynthesis materials. This also applies to pediatric craniofacial surgery. Various resorbable materials have already been developed in order to avoid costly and risky second operations to remove metal in children. However, none of these resorbable materials have been able to completely replace the previous gold standard, titanium, in a satisfactory manner. This has led to the need for a new resorbable osteosynthesis material that fulfills the requirements for biocompatibility, stability, and uniform resorption. In our previous in vitro and in vivo work, we were able to show that molybdenum fulfills these requirements. To further confirm these results, we conducted a proof of concept in four domestic pigs, each of which was implanted with a resorbable molybdenum implant. The animals were then examined daily for local inflammatory parameters. After 54 days, the animals were euthanized with subsequent computer tomography imaging. We also removed the implants together with the surrounding tissue and parts of the spleen, liver, and kidney for histopathological evaluation. The molybdenum implants were also analyzed metallographically and using scanning electron microscopy. A blood sample was taken pre- and post-operatively. None of the animals showed clinical signs of inflammation over the entire test period. Histopathologically, good tissue compatibility was found. Early signs of degradation were observed after 54 days, which were not sufficient for major resorption. Resorption is expected with longer in situ residence times based on results of similar earlier investigations. [ABSTRACT FROM AUTHOR]

Purpose: To determine the histological effects of ultraviolet light and cold atmospheric plasma treatment on the osseointegration of titanium implants in vivo. Materials and methods: Six juvenile pigs were divided into three groups of two animals each. A total of 54 titanium implants were placed randomly in the pigs’ calvarial bone (nine implants per pig). Of these, 18 implants served as untreated controls. The remaining 36 implants served as the experimental group and were treated with either ultraviolet light or argon plasma for 12 minutes each prior to insertion. Two pigs in each group were kept until 2, 4 and 8 weeks and then sacrificed. Resonance frequency analysis was conducted after implant placement and at the time of sacrifice. Osseointegration was evaluated using microcomputed tomography scans and histomorphometrical analysis. Results: After initial loss, all implants showed a constant increase in implant stability quotient values over time without significant differences between the groups. The bone–implant contact values increased steadily for all implants over 8 weeks of healing. Surface-treated implants showed significantly higher bone–implant contact values compared to untreated implants at each time point. Bone area fraction occupancy values were almost always higher following both treatment methods; however, differences were only significant after 4 and 8 weeks for the cold atmospheric plasma group and after 4 weeks for the ultraviolet light group. Conclusions: Ultraviolet light and cold atmospheric plasma may improve histomorphometrical osseointegration of titanium implants significantly. [ABSTRACT FROM AUTHOR]