Use of surgical bone cement to increase the projection of the nasomaxillary buttress in a case of orthognathic surgery. Technical note

The soft tissue outcome of the projection at the level of the nasomaxillary buttress is difficult to manage in cases of severe hypoprojection, being orthognathic surgery resolutive at the occlusal level but sometimes insufficient at the level of esthetic outcome. The literature describes the use of alloplastic prostheses and autologous bone grafts, but there are few documented cases of the use of premolded surgical cement for this purpose. The main advantage of the use of bone cement over the alternatives described is its ability to be premolded for customization, low cost, easy availability, speed of preparation and minimal comorbidity. This technical note describes the surgical steps and outcome of the use of surgical bone cement for projection augmentation at this level, including notes on preparation, premolding and fixation. Key words:Orthognathic surgery, maxillary surgery, surgical bone cement, nasomaxillary buttress

Adipose-derived stem cells and platelet-rich plasma for preventive treatment of bisphosphonate-related osteonecrosis of the jaw in a murine model

This is the author’s version of a work that was accepted for publication in Journal of Cranio-Maxillofacial Surgery. A definitive version was subsequently published in Journal of Cranio-Maxillofacial Surgery 43.7 (2015) DOI: 10.1016/j.jcms.2015.04.026Objectives: The main challenge in treating bisphosphonate-related osteonecrosis of the jaw (BRONJ) is the absence of an effective established treatment. We aimed to compare different potentially preventive treatments for BRONJ after dental extractions in zoledronic acid (ZA)-treated animals. We studied the local application of different combinations of adipose-derived stem cells (ASCs) with or without previous stimulation with bone morphogenetic protein 2 (BMP-2) and platelet-rich plasma (PRP) in rats. Material and methods: Fifty-six male Wistar rats were treated with ZA for 9 weeks. Dental extractions were performed in the eighth week, and the animals were divided into 4 groups. In group 1 (n ¼ 14), alveolar coverage with mucoperiosteal flap was performed. In group 2 (n ¼ 14), PRP was applied over the sockets and covered with the flap. In group 3 (n ¼ 15), allogeneic ASCs with PRP were applied and covered with the flap. In group 4 (n ¼ 13), animals were treated with ASCs cultured with BMP-2, PRP, and flap coverage. Histologic, fluorescence, and radiologic studies of the maxillae were performed. Results: ASC-treated animals showed lower frequency of osteonecrosis (14% vs 50%, p ¼ 0.007) and greater bone turnover (p ¼ 0.024) and osteoclast count (p ¼ 0.045) than those not receiving the ASC treatment. Conclusions: In this high-risk model, ASC-based treatments seem to prevent BRONJ more effectively than mucosal flap with or without PRP. The combination of ASCs and PRP appears to be synergistic, and the addition of BMP-2 could further improve the resultsThis study was supported by a grant from the Spanish Ministry of Health and Consumer Affairs (FIS PI10/01991) and a RETICS grant from ISCIII (RD12/0019/0035) and the Education Council of Madrid (P2010/BMD-2420)

Bisphosphonate-related osteonecrosis. Application of adipose-derived stem cells in an experimental murine model

Bisphosphonate-related osteonecrosis of the jaw is a pathological condition without effective established treatment and preventive strategies. The aim of this study was to analyse the effect of adipose-derived stem cells (ASC) in an experimental murine model of osteonecrosis. 38 Wistar rats were injected intraperitoneally with zoledronic acid. After treatment, upper jaw molars were extracted. The animals were randomly assigned to one of two groups. In the control group, saline solution was applied over the alveolar sockets after the tooth extractions. In the treatment group, ASCs were applied instead of saline solution. The control and treatment groups were subdivided based on the time of euthanasia. A clinical and histological analysis was performed. The presence of osteonecrosis in alveolar bone was observed in a similar distribution in both groups. In the ASC-treated group, new bone formation was greater than in controls. In this study, application of ASCs showed greater new bone formation in an osteonecrosis-like murine model. Previous inhibited post-extraction bone remodelling could be reactivated, and these findings appeared to be secondary to implantation of ASCs

Virtual Surgical Planning and Customized Subperiosteal Titanium Maxillary Implant (CSTMI) for Three Dimensional Reconstruction and Dental Implants of Maxillary Defects after Oncological Resection: Case Series

Maxillectomies cause malocclusion, masticatory disorders, swallowing disorders and poor nasolabial projection, with consequent esthetic and functional sequelae. Reconstruction can be achieved with conventional approaches, such as closure of the maxillary defect by microvascular free flap surgery or prosthetic obturation. Four patients with segmental maxillary defects that had been reconstructed with customized subperiosteal titanium maxillary implants (CSTMI) through virtual surgical planning (VSP), STL models and CAD/CAM titanium mesh were included. The smallest maxillary defect was 4.1 cm and the largest defect was 9.6 cm, with an average of 7.1 cm. The reconstructed maxillary vertical dimension ranged from 9.3 mm to 17.4 mm, with a mean of 13.17 mm. The transverse dimension of the maxilla at the crestal level was attempted to be reconstructed based on the pre-excision CT scan, and these measurements ranged from 6.5 mm in the premaxilla area to 14.6 mm at the posterior level. All patients were rehabilitated with a fixed prosthesis on subperiosteal implants with good esthetic and functional results. In conclusion, we believe that customized subperiosteal titanium maxillary implants (CSTMI) are a safe alternative for maxillary defects reconstruction, allowing for simultaneous dental rehabilitation while restoring midface projection. Nonetheless, prospective and randomized trials are required with long-term follow-up, to assess its long-term performance and safety

Prognostic Value of Lymph Node Density in Lingual Squamous Cell Carcinoma

Lymph node density (LND)—the proportion of positive nodes among the total number of resected nodes—has emerged as a reliable prognostic factor in solid tumors. This study aims to assess the importance of LND in lingual squamous cell carcinoma (LSCC) and its prognostic involvement. A retrospective longitudinal study with 62 patients was performed. All patients were diagnosed with LSCC and submitted for tumor resection and neck dissection. Patients were stratified into low (<0.04) and high risk (≥0.04) based on LND. We analyzed the impact of LND on overall survival (OS) and disease-free survival (DFS), as well as the relationship between LND and the pathological staging, the involvement of positive margins, depth of invasion (DOI) and perineural infiltration. This study provides a substantial relationship between lymph node density (LND), overall survival (OS) and disease-free survival (DFS) in lingual squamous cell carcinoma (LSCC). A statistically significant distribution was found between LND, perineural infiltration and pathological staging, whereas no association was found with the rest of the prognostic variables analyzed

Discovering HIV related information by means of association rules and machine learning

Acquired immunodeficiency syndrome (AIDS) is still one of the main health problems worldwide. It is therefore essential to keep making progress in improving the prognosis and quality of life of affected patients. One way to advance along this pathway is to uncover connections between other disorders associated with HIV/AIDS-so that they can be anticipated and possibly mitigated. We propose to achieve this by using Association Rules (ARs). They allow us to represent the dependencies between a number of diseases and other specific diseases. However, classical techniques systematically generate every AR meeting some minimal conditions on data frequency, hence generating a vast amount of uninteresting ARs, which need to be filtered out. The lack of manually annotated ARs has favored unsupervised filtering, even though they produce limited results. In this paper, we propose a semi-supervised system, able to identify relevant ARs among HIV-related diseases with a minimal amount of annotated training data. Our system has been able to extract a good number of relationships between HIV-related diseases that have been previously detected in the literature but are scattered and are often little known. Furthermore, a number of plausible new relationships have shown up which deserve further investigation by qualified medical experts

Revista Temas Agrarios Volumen 26; Suplemento 1 de 2021

1st International and 2nd National Symposium of Agronomic Sciences: The rebirth of the scientific discussion space for the Colombian Agro.1 Simposio Intenacional y 2 Nacional de Ciencias Agronómicas: El renacer del espacio de discusión científica para el Agro colombiano

Evaluation of a quality improvement intervention to reduce anastomotic leak following right colectomy (EAGLE): pragmatic, batched stepped-wedge, cluster-randomized trial in 64 countries

Background Anastomotic leak affects 8 per cent of patients after right colectomy with a 10-fold increased risk of postoperative death. The EAGLE study aimed to develop and test whether an international, standardized quality improvement intervention could reduce anastomotic leaks. Methods The internationally intended protocol, iteratively co-developed by a multistage Delphi process, comprised an online educational module introducing risk stratification, an intraoperative checklist, and harmonized surgical techniques. Clusters (hospital teams) were randomized to one of three arms with varied sequences of intervention/data collection by a derived stepped-wedge batch design (at least 18 hospital teams per batch). Patients were blinded to the study allocation. Low- and middle-income country enrolment was encouraged. The primary outcome (assessed by intention to treat) was anastomotic leak rate, and subgroup analyses by module completion (at least 80 per cent of surgeons, high engagement; less than 50 per cent, low engagement) were preplanned. Results A total 355 hospital teams registered, with 332 from 64 countries (39.2 per cent low and middle income) included in the final analysis. The online modules were completed by half of the surgeons (2143 of 4411). The primary analysis included 3039 of the 3268 patients recruited (206 patients had no anastomosis and 23 were lost to follow-up), with anastomotic leaks arising before and after the intervention in 10.1 and 9.6 per cent respectively (adjusted OR 0.87, 95 per cent c.i. 0.59 to 1.30; P = 0.498). The proportion of surgeons completing the educational modules was an influence: the leak rate decreased from 12.2 per cent (61 of 500) before intervention to 5.1 per cent (24 of 473) after intervention in high-engagement centres (adjusted OR 0.36, 0.20 to 0.64; P &lt; 0.001), but this was not observed in low-engagement hospitals (8.3 per cent (59 of 714) and 13.8 per cent (61 of 443) respectively; adjusted OR 2.09, 1.31 to 3.31). Conclusion Completion of globally available digital training by engaged teams can alter anastomotic leak rates. Registration number: NCT04270721 (http://www.clinicaltrials.gov)