Evaluation of torque expression of four commercially available self-ligating brackets: A finite element study

This FEM study was carried out to investigate the torque expression of different self-ligating brackets and arch wire combinations on the tooth and its supporting structures. Two Active (Innovation-R and Time) and Passive (Smart Clip 3 and Damon3MX) self-ligating bracket systems were selected and one conventional (Ovation) bracket system served as control. Upper Right Central Incisor Stainless Steel Roth Prescription bracket with slot dimension of 0.022 x 0.028 inches was used in all the groups. The brackets were tested against three S.S. archwire dimensions (0.017 x 0.025, 0.019 x 0.025 and 0.021 x 0.025 inches). A 3-dimensional model of the right maxillary central incisor and its supporting structures was generated from a Computed Tomography scan of a dry human skull by a CAD/CAE program. The brackets were scanned and 3-dimensional models were designed with Comet 5 White Light Scanner. The close geometric diagram for the bracket, tooth and its supporting structures was prepared using Ansys Workbench Version 11. The bracket of the maxillary central right incisor was rotated from the neutral position by a total of 20 degrees. The angle of engagement and the resultant forces (stress concentration) were evaluated at 0mm, 4mm, 8mm and 12mm from the apex for different archwire-bracket combinations were recorded using the same software. This FEM study was carried out to investigate the torque expression of different self-ligating brackets and arch wire combinations on the tooth and its supporting structures. Two Active (Innovation-R and Time) and Passive (Smart Clip 3 and Damon3MX) self-ligating bracket systems were selected and one conventional (Ovation) bracket system served as control. Upper Right Central Incisor Stainless Steel Roth Prescription bracket with slot dimension of 0.022 x 0.028 inches was used in all the groups. The brackets were tested against three S.S. archwire dimensions (0.017 x 0.025, 0.019 x 0.025 and 0.021 x 0.025 inches). A 3-dimensional model of the right maxillary central incisor and its supporting structures was generated from a Computed Tomography scan of a dry human skull by a CAD/CAE program. The brackets were scanned and 3-dimensional models were designed with Comet 5 White Light Scanner. The close geometric diagram for the bracket, tooth and its supporting structures was prepared using Ansys Workbench Version 11. The bracket of the maxillary central right incisor was rotated from the neutral position by a total of 20 degrees. The angle of engagement and the resultant forces (stress concentration) were evaluated at 0mm, 4mm, 8mm and 12mm from the apex for different archwire-bracket combinations were recorded using the same software

Osteochondroma of talus and coalition of talocrural and intercuneiform joints - surgical management

Osteochondroma of talus is rare benign tumour. Tarsal coalition is a condition in which two or more tarsal bones are joined by non-osseous bridges of cartilage or fibrocartilage or by osseous bridges. Association of Talus osteochondroma with coalition of tarsal bones is extremely rare and has not been reported in the literature before. We are herewith reporting a case of osteochondroma of the talus with coalition of intercuneiform and talocrural joint in an 11-year-old male patient. Patient noticed swelling around ankle and pain on strenuous activities. CT scan confirmed the diagnosis. We did complete extraperiosteal excision of the osteochondroma and resection of tarsal coalition. Histopathological examination confirmed the diagnosis of osteochondroma. At one-year follow-up there is no recurrence of the tumour and patient had full range of motion. Complete extraperiosteal excision of the osteochondroma along with resection of tarsal coalition is important for complete eradication and preventing a recurrence

Functional outcome of minimally invasive plate osteosynthesis with the use of locking plate in fracture distal end of tibia

Background : Distal tibia fractures or pilon fractures are usually the result of combined compressive and shearing forces, which may lead to instability of the metaphysis. Poor vascularity, lack of muscle cover and frequent intra-articular extension often make these fractures very challenging to manage. There are plenty of options available to treat a distal tibia fracture which includes intramedullary nailing, external fixation, open reduction and internal fixation and minimally invasive plate osteosynthesis (MIPO). The aim of this study was to evaluate the results of MIPO with respect to the healing of fracture site, the incidences of complications and to conclude whether MIPO circumvents the problems of formal open reduction and fixation with other implants.Methods: A series of forty patients with fracture of the distal tibia on preoperative X-rays were treated with minimally invasive plate osteosynthesis using pre-contoured locking plates from June 2014 to October 2018 and followed up at regular intervals with X-rays and monitoring for complications.Result: The functional scores were evaluated using Teeny and Wiss clinical rating system for ankle joints. Thirty-two patients had an ‘Excellent’ or ‘Good’ outcome. One patient was diagnosed with a soft tissue complication and delayed union and 3 patients were diagnosed with malunion without significant functional disability at follow up. Conclusion: Minimally invasive plate osteosynthesis with pre-contoured locking plates is associated with high union rate and good functional outcomes. It is an effective treatment modality for distal tibia fractures

DISCO: Dynamic and Invariant Sensitive Channel Obfuscation for deep neural networks

Recent deep learning models have shown remarkable performance in image classification. While these deep learning systems are getting closer to practical deployment, the common assumption made about data is that it does not carry any sensitive information. This assumption may not hold for many practical cases, especially in the domain where an individual's personal information is involved, like healthcare and facial recognition systems. We posit that selectively removing features in this latent space can protect the sensitive information and provide a better privacy-utility trade-off. Consequently, we propose DISCO which learns a dynamic and data driven pruning filter to selectively obfuscate sensitive information in the feature space. We propose diverse attack schemes for sensitive inputs \& attributes and demonstrate the effectiveness of DISCO against state-of-the-art methods through quantitative and qualitative evaluation. Finally, we also release an evaluation benchmark dataset of 1 million sensitive representations to encourage rigorous exploration of novel attack schemes.Comment: Presented at CVPR 202

A study of minimally invasive percutaneous plate osteosynthesis for tibial plateau fractures

Background: Fractures of proximal tibia involve a major weight-bearing joint and are serious injuries, which, if not treated well, result in functional impairment. To preserve normal knee function one must strive to maintain joint congruity, preserve the normal mechanical axis, ensure joint stability and restore a full range of motion. This is a formidable task to accomplish, especially in the face of associated medical conditions of the patients.Methods: In our study, 30 cases were selected. Selection of cases were done on the basis of X-rays. Schatzker type I, II, III, IV, V & VI included in study. Criteria for acceptable reduction 1) <5 mm of articular step; 2) <5 mm of articular depression. Each case is referred to one set of tibial plateau fracture, showing distribution of tibia plateau fractures that we treated with MIPPO. Clinical follow-up examination was performed at 4, 6, 10, 12 weeks and 3, 6 months. Clinico-radiological assessment was done at 3 month and grading was done. Patients were evaluated according to grading minimum 3 months after injury.Results: Our study of 30 tibial plateau fractures confirms that the MIPPO technique is an excellent treatment modality in case of tibial plateau fractures. We observed these fractures mainly in age group of 30-40 years, which were involved in road traffic accident. Tibial plateau fractures seen in elder age group were mainly due to abnormal loading patterns on the leg. We have found oblique views very much informative especially for posterolateral or posteromedial displacement, articular depression which helps to plan the position and direction of screws to be used for fixation. Conclusions: In view of the excellent results obtained with this technique, we advocate MIPPO over conventional open reduction and internal fixation technique for tibial plateau fracture fixation

Magnetic Resonance Imaging and GeneXpert: A Rapid and Accurate Diagnostic Tool for the Management of Tuberculosis of the Spine

Study DesignRetrospective study.PurposeThe aim of this study was to analyze various diagnostic tools, including GeneXpert, for the management of tuberculosis of the spine.Overview of LiteratureTraditional diagnostic methods of microscopy, histology, and culture have low sensitivity and specificity for the management of tuberculosis of the spine.MethodsOf the 262 treated cases of spinal tuberculosis, data on 1 year follow-up was available for 217 cases. Of these, only 145 cases with a confirmed diagnosis were selected for retrospective analysis.ResultsIn 145 of the 217 patients (66.80%), diagnosis was confirmed on the basis of a culture. Of the 145 patients with a confirmed diagnosis, 98 (66.20%) patients were diagnosed on the basis of clinical presentation, whereas 123 (84.8%) exhibited a typical magnetic resonance imaging (MRI) picture. In 99 surgically treated patients, the diagnosis was confirmed on the basis of an intraoperative tissue biopsy. Among the 46 patients treated conservatively, 35 underwent a transpedicular biopsy, 4 patients underwent computed tomography-guided biopsy, 6 patients were diagnosed on the basis of material obtained from a cold abscess, and 1 patient underwent an open biopsy. The sensitivity of the culture for the detection of Mycobacterium tuberculosis was 66.80% (145/217) in our patients. Among the cases in which GeneXpert was used, the sensitivity for the detection of Mycobacterium tuberculosis was 93.4% (43/46). Moreover, the sensitivity of GeneXpert to detect rifampicin resistance was 100% (7/7) in our study.ConclusionsMajority of the patients with tuberculosis of the spine can be diagnosed on the basis of a typical radiological presentation via MRI. In our study, 84.8% cases exhibited typical MRI findings. For patients presenting with atypical MRI features, a rapid and accurate diagnosis is possible by combining GeneXpert with MRI. The combined use of MRI and GeneXpert is a rapid and highly sensitive tool to diagnose tuberculosis and rifampicin resistance in patients with tuberculosis of the spine. Furthermore, we achieved a 97.9% sensitivity for the detection of Mycobacterium tuberculosis and 100% sensitivity for the detection of rifampicin resistance in our study