A stepwise approach to chainsaw kickback injury of the nasoorbital complex: a case-based meta-narrative review.

PURPOSE: This article outlines the management of a rare and severe nasoorbital injury resulting from a chainsaw kickback accident in a 60-year-old male. A meta-narrative review of English, French, and German literature indexed in PubMed, Embase, and the Cochrane Library up to January 8, 2024, accompanies the case report. METHODS: This was a case report combined with a comprehensive review based on the 2011 Oxford Centre for Evidence-Based Medicine's highest and most recent level of evidence (LoE) and highest recommendation grade (RG). Rigorous selection criteria were applied. RESULTS: The patient had an open nasal fracture, complex lacerations, and avulsion of the left eyelid, lateral orbital wall and lateral rectus muscle. Staged surgical interventions comprised repositioning and fixation of the fractured nose, buccal mucosal grafting for nasal mucosa and conjunctiva repair, titanium mesh and polydioxanone sheet for lateral orbital wall reconstruction, and subsequent muscle and eyelid repair. The second intervention 3 months postsurgery addressed lateral ectropion, nasal dorsal hump, and nasolacrimal system issues. Despite the rarity of such injuries, evidence-based discussions were conducted. CONCLUSIONS: Complex nasoorbital trauma resulting from chainsaw kickback necessitates a meticulous, staged surgical approach. The inside-out technique proved effective in addressing various challenges. This article concludes with evidence-based recommendations, highlighting the importance of adapting established principles to unique nature of these injuries.

Current German Recommendations and International Research on the Use of COVID-19 Boosters among Health Care Providers in 2024: A Narrative Review.

While the World Health Organization (WHO) has de-escalated coronavirus disease 2019 (COVID-19) from a global health emergency, ongoing discussions persist as new viral variants. This article aimed to consolidate German recommendations and international research to offer health care providers (HCPs) a comprehensive guide on COVID-19 boosters in 2024. The review outlines key recommendations from the German Robert Koch Institute. HCPs should receive COVID-19 boosters at least 12 months after their last vaccination or COVID-19 infection, contingent on the prevalent viral variant(s) in the region. However, excessive doses and/or frequent boosters, especially with mRNA vaccines, may lead to immune imprinting, T-cell exhaustion, and immunoglobulin (Ig) switching. Notably, this review highlights the significance of Ig, particularly IgA and IgG subclasses, in influencing infection risk and disease progression. Furthermore, it explores the implications of mRNA vaccine technology and potential adverse effects related to excessive dosing. In conclusion, this article provides a comprehensive analysis of COVID-19 vaccine boosters for HCPs, synthesising current recommendations, scientific debates, and considerations for optimising protection against SARS-CoV-2 in the evolving landscape of the post-pandemic era.

Finetuning of GLIDE stable diffusion model for AI-based text-conditional image synthesis of dermoscopic images.

Background: The development of artificial intelligence (AI)-based algorithms and advances in medical domains rely on large datasets. A recent advancement in text-to-image generative AI is GLIDE (Guided Language to Image Diffusion for Generation and Editing). There are a number of representations available in the GLIDE model, but it has not been refined for medical applications. Methods: For text-conditional image synthesis with classifier-free guidance, we have fine-tuned GLIDE using 10,015 dermoscopic images of seven diagnostic entities, including melanoma and melanocytic nevi. Photorealistic synthetic samples of each diagnostic entity were created by the algorithm. Following this, an experienced dermatologist reviewed 140 images (20 of each entity), with 10 samples originating from artificial intelligence and 10 from original images from the dataset. The dermatologist classified the provided images according to the seven diagnostic entities. Additionally, the dermatologist was asked to indicate whether or not a particular image was created by AI. Further, we trained a deep learning model to compare the diagnostic results of dermatologist versus machine for entity classification. Results: The results indicate that the generated images possess varying degrees of quality and realism, with melanocytic nevi and melanoma having higher similarity to real images than other classes. The integration of synthetic images improved the classification performance of the model, resulting in higher accuracy and precision. The AI assessment showed superior classification performance compared to dermatologist. Conclusion: Overall, the results highlight the potential of synthetic images for training and improving AI models in dermatology to overcome data scarcity.

Polyclonal Anti-D Antibodies Significantly Reduce the Rate of Miscarriages in Rh(D) positive Women with Recurrent Pregnancy loss.

Background: Macrophages play a key role in all environmental conditions surrounding pregnancy. Coating of autologous red blood cells (RBCs) with polyclonal antibodies to Rh(D) antigen may result in an immunomodulation and improved outcome in Rh(D) positive women with recurrent pregnancy loss (RPL). Methods: A total of 60 Rh(D) positive women (age 23 to 45 years) with a history of RPL and ineffective treatment with low molecular weight heparin (LMWH) and/or aspirin were included in this retrospective study. In addition to this treatment, Anti-D (300 µg) was given subcutaneously to each woman either prior to pregnancy and/or two times within 12 weeks of gestation. Results: Treatment with Anti-D in non-responders to heparin/aspirin resulted in successful pregnancies in 67% of all cases. The remaining women had only aborts (23%) or did not become pregnant (10%). None of the treated women has developed anemia due to this treatment or any other significant adverse reaction. The rate of successful pregnancies does not appear to be influenced by the administration of: Anti-D prior to pregnancy, age, thrombophilia or previous alive births. Conclusion: The improved outcome following the administration of Anti-D in women with RPL might be explained by immune modulations induced by different immune reactions including polarization of decidual macrophages. The results obtained in this study clearly indicate that Anti-D is safe and highly effective in treatment of Rh(D) positive women with RPL. However, further studies are required to support our results and to find out the optimal dose and timing of Anti-D administration.

Harmonizing corporate carbon footprints.

Global greenhouse gas emissions need to reach net-zero around mid-century to limit global warming to 1.5 °C. This decarbonization challenge has, inter alia, increased the political and societal pressure on companies to disclose their carbon footprints. As a response, numerous companies announced roadmaps to become carbon neutral or even negative. The first step on the journey towards carbon neutrality, however, is to quantify corporate emissions accurately. Current carbon accounting and reporting practices remain unsystematic and not comparable, particularly for emissions along the value chain (so-called scope 3). Here we present a framework to harmonize scope 3 emissions by accounting for reporting inconsistency, boundary incompleteness, and activity exclusion. In a case study of the tech sector, we find that corporate reports omit half of the total emissions. The framework we present may help companies, investors, and policy makers to identify and close the gaps in corporate carbon footprints.

Energy Consumption of Cryptocurrencies Beyond Bitcoin.

Ulrich Gallersdörfer is a research associate in the Department of Informatics at the Technical University of Munich. His research focuses on identity management in blockchains. His interest extends to further aspects of the technology, ranging from environmental implications to data analytics applications. Lena Klaaßen is a graduate student at TUM School of Management at the Technical University of Munich. She is specialized in energy markets and accounting. Her research focuses on carbon accounting in the corporate and cryptocurrency space. She has previously analyzed blockchain-related firms for a venture capital fund. Christian Stoll conducts research at the Center for Energy and Environmental Policy Research at the Massachusetts Institute of Technology and at the Center for Energy Markets of the Technical University of Munich. His research focuses on the implications of climate change from an economic point of view.

COVID-19: Clinching the Climate Opportunity.

The coronavirus disease 2019 (COVID-19) pandemic has triggered the largest drop in greenhouse gas emissions since World War II. Evolving mobility patterns, in particular, have shown the short-term mitigation potential of behavioral change. Sustaining such changes could abate 15% of all transportation emissions with limited net impacts on societal well-being.

Current concepts in cleft care: A multicenter analysis.

The current surgical techniques used in cleft repair are well established, but different centers use different approaches. To determine the best treatment for patients, a multi-center comparative study is required. In this study, we surveyed all craniofacial departments registered with the German Society of Maxillofacial Surgery to determine which cleft repair techniques are currently in use. Our findings revealed much variation in cleft repair between different centers. Although most centers did use a two-stage approach, the operative techniques and timing of lip and palate closure were different in every center. This shows that a retrospective comparative analysis of patient outcome between the participating centers is not possible and illustrates the need for prospective comparative studies to establish the optimal technique for reconstructive cleft surgery.

In vitro study of adhesive polymethylmethacrylate bone cement bonding to cortical bone in maxillofacial surgery.

PURPOSE: In the treatment of midface fractures, the fragments are immobilized using screws and plates for osteosynthesis until reunion has occurred. This method involves drilling holes for the insertion of the screws, which can be associated with additional fracturing of the corresponding bone owing to the complex architecture and thin layers of facial bone. To alleviate this problem, new adhesive techniques for fixing the plates for osteosynthesis have been investigated, mitigating the detrimental effects of screw hole drilling. In the present experimental study, the strength of this adhesive bond and its resistance to hydrolysis were investigated. MATERIALS AND METHODS: To determine the adhesive bonding strength, a tension test was implemented. Osteosynthesis plates with screw holes 1.3 mm in diameter were fixed to cortical bone samples of bovine femur using ultraviolet (UV) light-curing polymethylmethacrylate bone cement. To facilitate bonding, the surface of the bone was conditioned with an amphiphilic bonding agent before cementing. UV light curing was implemented using either a conventional UV unit, such as is used in dentistry, or with a specialized UV unit with a limited emission spectrum but high luminosity. Reference control samples were prepared without application of the bone bonding agent. After this procedure, the samples were stored for 1 to 7 days at 37°C submerged in 0.9% saline solution before being subjected to the tension test. RESULTS: Without the bone bonding agent, the bonding strength was 0.2 MPa. The primary average bonding strength at day 0 was 8.5 MPa when cured with the conventional UV unit and 14 MPa for the samples cured with the specialized UV unit. An almost constant average bond strength of 8 and 16 MPa was noted for all samples stored up to 7 days after curing with the conventional and specialized UV unit, respectively. CONCLUSION: With the development of a new bone bonding agent, a method is now available to promote the bonding between the hydrophilic bone surface and the hydrophobic polymethylmethacrylate bone cement by creating an interlayer that is beneficial for adhesion. In the present in vitro study, the strength of this bond and its resistance to hydrolysis were investigated. This new method could have clinical bearing in cases in which conventional fixation with screws and plates is limited, such as can occur in comminuted fractures. The observed average bonding strengths of 8 to 16 MPa support the implementation of this technique in nonload-bearing regions such as the midface, facilitating immobilization until the bone reunion is complete.

A new adhesive technique for internal fixation in midfacial surgery.

BACKGROUND: The current surgical therapy of midfacial fractures involves internal fixation in which bone fragments are fixed in their anatomical positions with osteosynthesis plates and corresponding screws until bone healing is complete. This often causes new fractures to fragile bones while drilling pilot holes or trying to insert screws. The adhesive fixation of osteosynthesis plates using PMMA bone cement could offer a viable alternative for fixing the plates without screws. In order to achieve the adhesive bonding of bone cement to cortical bone in the viscerocranium, an amphiphilic bone bonding agent was created, analogous to the dentin bonding agents currently on the market. METHODS: The adhesive bonding strengths were measured using tension tests. For this, metal plates with 2.0 mm diameter screw holes were cemented with PMMA bone cement to cortical bovine bone samples from the femur diaphysis. The bone was conditioned with an amphiphilic bone bonding agent prior to cementing. The samples were stored for 1 to 42 days at 37 degrees C, either moist or completely submerged in an isotonic NaCl-solution, and then subjected to the tension tests. RESULTS: Without the bone bonding agent, the bonding strength was close to zero (0.2 MPa). Primary stability with bone bonding agent is considered to be at ca. 8 MPa. Moist storage over 42 days resulted in decreased adhesion forces of ca. 6 MPa. Wet storage resulted in relatively constant bonding strengths of ca. 8 MPa. CONCLUSION: A new amphiphilic bone bonding agent was developed, which builds an optimizied interlayer between the hydrophilic bone surface and the hydrophobic PMMA bone cement and thus leads to adhesive bonding between them. Our in vitro investigations demonstrated the adhesive bonding of PMMA bone cement to cortical bone, which was also stable against hydrolysis. The newly developed adhesive fixing technique could be applied clinically when the fixation of osteosynthesis plates with screws is impossible. With the detected adhesion forces of ca. 6 to 8 MPa, it is assumed that the adhesive fixation system is able to secure bone fragments from the non-load bearing midfacial regions in their orthotopic positions until fracture consolidation is complete.

Evaluation of the accuracy of three different computer-aided surgery systems in dental implantology: optical tracking vs. stereolithographic splint systems.

OBJECTIVES: In dental implant surgery, computer-aided surgery (CAS) techniques can provide a high medical benefit. Two different techniques are established for transferring a CAS treatment planning to the patient: the use of surgical templates (splints) or intraoperative navigation using optical tracking. The aim of this study was to evaluate the total application accuracy of three different CAS systems (Artma virtual patient, RoboDent LapAccedo, Materialise SurgiGuide): two featuring optical tracking, one featuring stereolithographically manufactured splints. MATERIALS AND METHODS: A total of 120 implants were placed into 20 human cadaver mandibles. Preoperative computed tomography (CT) scans imported to the corresponding software were used to plan the implant positions on the computer. Implant placement was performed using either optical tracking or stereolithographic splints. Postoperative CT scans were used to obtain the achieved implant positions. A semi-automatic approach was developed to compare planned and achieved implant positions. Deviations between planned and achieved positions were measured for each implant in position (Delta xy), depth (Delta z) and axis (Delta phi). CONCLUSION: Despite the different techniques of transfer, no statistically significant differences were found between all groups. The accuracy achieved corresponded well with the spatial resolution of the CT Scans used.

Quantitative computed tomography bone mineral density measurements in irradiated and non-irradiated minipig alveolar bone: an experimental study.

OBJECTIVE: The objective of this study was to analyse the effect of irradiation on bone mineral density (BMD). MATERIALS AND METHODS: All maxillary and mandibular pre-molars and molars of six minipigs were extracted. After a 3-month healing period, the maxilla and mandibles of three minipigs received three irradiation exposures at a total dose of 24 Gy. At 3 months after irradiation, quantitative computed tomography (QCT) was performed. As a reference, a calibration bone phantom with pre-determined BMD was attached to the head of the minipigs. The QCT data were imported into a software program to calculate the BMD of the alveolar bone and the calibration bone phantom. In order to compare BMD values of individual minipigs, the so-called bone mineral density quotient (BMDQ) was created, dividing the BMD value of the alveolar bone by the BMD value of the calibration bone phantom. RESULTS: Mean BMDQ values appeared to be higher in irradiated than in non-irradiated minipigs. However, the difference was not significant. In both irradiated and non-irradiated minipigs, the average mandibular BMDQ values were statistically significantly higher than the average maxillary BMDQ values (P=0.003). The P-values of the Student t-test, determining the irradiation effect, were 0.11 for maxillary, 0.14 for mandibular, and 0.07 for overall peri-implant BMDQ. P-values of the non-parametric Mann-Whitney test were all 0.05. CONCLUSION: It could be concluded that, 3 months after irradiation, the BMD of irradiated alveolar minipig bone was increased, when compared with non-irradiated alveolar minipig bone. However, the increase was not statistically significant.

Implant stability during osseointegration in irradiated and non-irradiated minipig alveolar bone: an experimental study.

OBJECTIVES: Primary implant stability is related to local bone density. After insertion of an implant, implant stability is subject to changes due to bone remodeling. In patients who have undergone radiotherapy in the head and neck region, implant stability is impaired because irradiation reduces bone vitality. The current study was designed to monitor and test implant stability immediately after implant placement and during osseointegration in irradiated and non-irradiated minipig alveolar bone. MATERIALS AND METHODS: All maxillary and mandibular premolars and molars of six adult Göttingen minipigs were extracted. The maxilla and mandible of three minipigs received three irradiation exposures at a total dose of 24 Gy. After irradiation, five initial implant holes were drilled in the residual alveolar ridge of each edentulous site. In order to assess bone vascularity, laser Doppler flowmetry recordings were carried out in the initial holes. A total of 120 implants were placed in the six minipigs. Subsequently, and at 8, 16, and 24 weeks after implant placement, implant stability was recorded by resonance frequency analysis (RFA). RFA values were expressed as an implant stability quotient (ISQ). RESULTS: ISQ values recorded immediately after implant placement showed no differences between irradiated and non-irradiated minipigs. Repeated measurements at the four recording moments showed a decrease of ISQ values in all minipigs, being more pronounced in irradiated bone, when compared with non-irradiated bone. The results at the third and fourth recording moments showed a stabilization or even a slight increase of ISQ values. CONCLUSIONS: The results document the negative effect of irradiation on bone vascularity and hence on implant stability.

Disruption of the latent transforming growth factor-beta binding protein-1 gene causes alteration in facial structure and influences TGF-beta bioavailability.

Latent transforming growth factor-beta binding proteins are a family of extracellular matrix proteins comprising four isoforms (LTBP-1, -2, -3, -4) with different structures, tissue expression patterns and affinity for TGF-beta. So far, respective knockout models have highlighted some essential functions for LTBP-2, LTBP-3 and LTBP-4, while the physiological significance of LTBP-1 is only superficially known. Here we report for the first time the generation and characterization of a mouse model lacking both the long and short LTBP-1 isoform. Surprisingly, respective mice are viable and fertile. However, detailed X-ray analysis of the skull revealed a modified facial profile. In addition, the gene disruption induces a reduced biological activity of TGF-beta that became evident in an experimental model of hepatic fibrogenesis in which the LTBP-1 knockout animals were less prone to hepatic fibrogenesis. Furthermore, comparative cDNA microarray gene expression profiling of cultured hepatic stellate cells confirmed that respective nulls were less receptive to cellular activation and transdifferentiation into myofibroblasts. Therefore, we conclude that LTBP-1 has essential functions in the control of TGF-beta activation.

Assessment of vascularity in irradiated and nonirradiated maxillary and mandibular minipig alveolar bone using laser doppler flowmetry.

PURPOSE: The purpose of this animal study was to confirm that laser Doppler flowmetry (LDF) is a reproducible method for the assessment of maxillary and mandibular alveolar bone vascularity and that there is less vascularity in irradiated mandibular and maxillary bone compared to nonirradiated bone. MATERIALS AND METHODS: All maxillary and mandibular premolars and molars of 6 Göttingen minipigs were extracted. After a 3-month healing period, 3 minipigs received irradiation at a total dose of 24 Gy. Three months after irradiation, 5 holes were drilled in the residual alveolar ridge of each edentulous site in each minipig. Local microvascular blood flow around all 120 holes was recorded by LDF prior to implant placement. In 1 irradiated and 1 nonirradiated minipig, an additional hole was drilled in a right maxillary site to enable repeated LDF recordings. RESULTS: The alveolar bone appeared less vascularized in irradiated than in nonirradiated minipigs. The effect of radiation appeared more pronounced in the mandible than in the maxilla. LDF was demonstrated to be a reproducible method for assessing alveolar bone vascularity. However, recordings varied by edentulous site as well as by minipig. CONCLUSION: The authors' hypotheses regarding LDF and vascularity were supported. Further research validating the use of LDF in human beings, especially in those who have undergone radiation therapy for head and neck cancer, is necessary.

Cytokeratin expression patterns for distinction of odontogenic keratocysts from dentigerous and radicular cysts.

BACKGROUND: The clinical outcome of treatment of odontogenic cysts differs depending on separate entities. Particular clinical relevance must be attached to the distinction between odontogenic keratocysts, which have an evident tendency to recur, and other odontogenic cysts. The aim of this study was to evaluate cytokeratin (CK) expression patterns as an additional tool for characterization of different cysts as the histomorphologic appearance often is not decisive. METHODS: Thirty cases of dentigerous and radicular cysts respectively as well as 15 cases of odontogenic keratocysts were considered. Expression of CK 5/6, 7, 10, 13, 17, 19 and 20 was determined in addition to Ki-67 immunohistochemically. RESULTS: Expression of CK 17 was discernible in 93.3% of the odontogenic keratocysts, but only in 35.0% of dentigerous and radicular cysts under study (P < 0.001). CK 19 could be detected in 48.3% of dentigerous and radicular cysts, whereas odontogenic keratocysts were completely negative (P < 0.002). CONCLUSION: Immunohistochemical detection of CK 17 and 19 seems to be a valuable additional parameter distinguishing between odontogenic keratocysts and other odontogenic--especially dentigerous--cysts which clinically are likely the most significant differential diagnoses in this context. J Oral Pathol Med (2005) 34: 558-64.

Analysis of polymorphic TGFB1 codons 10, 25, and 263 in a German patient group with non-syndromic cleft lip, alveolus, and palate compared with healthy adults.

BACKGROUND: Clefts of the lip, alveolus, and palate (CLPs) rank among the most frequent and significant congenital malformations. Leu10Pro and Arg25Pro polymorphisms in the precursor region and Thr263Ile polymorphism in the prodomain of the transforming growth factor beta1 (TGF-beta1) gene have proved to be crucial to predisposition of several disorders. METHODS: In this study, polymorphism analysis was performed by real-time polymerase chain reaction (LightCycler) and TGF-beta1 levels determined by enzyme-linked immunosorbent assay. RESULTS: Only 2/60 Caucasian non-syndromic patients with CLP (3.3%) carried the Arg25Pro and another 2/60 patients (3.3%) the Thr263Ile genotypes, whereas, in a control group of 60 healthy Caucasian blood donors, these heterozygous genotypes were more frequent 16.7% having Arg25Pro (10/60; p < 0.035) and 10,0% having Thr263Ile (6/60), respectively. TGF-beta1 levels in platelet-poor plasma of heterozygous Arg25Pro individuals were lower than those of homozygous members (Arg25Arg) in the latter group, but this discrepancy narrowly failed to be significant. Although polymorphisms in codon 10 and 25 were associated with each other, no difference was found between patients and controls concerning the Leu10Pro polymorphism. CONCLUSIONS: The genetic differences in codons 25 and 263 suggest that TGF-beta1 could play an important role in occurrence of CLP, however, functional experiments will be required to confirm the mechanisms of disturbed development.

Orthodontic and surgical treatment of patients with congenital unilateral and bilateral mandibulofacial dysostosis.

AIM: Presentation of results following therapy of patients with different forms of mandibulofacial dysostosis. MATERIAL AND METHODS: Case reports of four patients, two with unilateral and two with bilateral mandibulofacial dysostosis, are presented. The symptoms and the problems involved in treatment are described. RESULTS: Protracted treatment resulted in improved facial symmetry, a harmonized profile, and acceptable occlusion. CONCLUSION: The rehabilitation of patients suffering from congenital facial malformations such as mandibulofacial dysostosis demands an experienced team of orthodontists and maxillofacial surgeons as well as persistence on the part of the patients and their families if good esthetic and functional results are to be achieved.