Maxillofacial fractures in the pediatric population are generally managed by conservative approaches such as soft diet and medication or semi-invasive procedures namely inter-maxillary fixation or circummandibular wiring.These approaches are preferred over any invasive treatment to minimize injury to the growing skeleton and tooth germs.Displaced fractures that cause functional problems such as restricted mouth opening,malocclusion or impaired breathing,mandate open reduction and internal fixation.However,surgical management is associated with morbidity related to general anesthesia,risk of injury to vital structures,and potential,skeletal or dental growth disturbances.This case report describes a non-invasive method of managing displaced,multiple fractures of the mandible in a pediatric patient,with the use of low intensity pulsed ultrasound to achieve favorable clinical outcomes and nil complications.Neither immobilization of the mandible with inter-maxillary fixation nor open reduction and internal fixation was used.Low intensity pulsed ultrasound therapy is painless and patient-friendly.
Elavenil PanneerselvamChandini RavikumarTrishala Annamalai RajanSasikala BalasubramanianKrishnakumar Raja V.B.
The small-angle neutron scattering(SANS)instrument,one of the first three instruments of the China Spallation Neutron Source(CSNS),is designed to probe the microscopic and mesoscopic structures of materials in the scale range 1–100 nm.A large-area ^(3)He tube array detector has been constructed and operates at the CSNS SANS instrument since August 2018.It consists of 120 linear position-sensitive detector tubes,each 1 m in length and 8 mm in diameter,and filled with ^(3)He gas at 20 bar to obtain a high detection efficiency.The ^(3)He tubes were divided into ten modules,providing an overall area of 1000 mm×1020 mm with a high count rate capability.Because each tube is installed independently,the detector can be quickly repaired in situ by replacing damaged tubes.To reduce air scattering,the SANS detector must operate in a vacuum environment(0.1 mbar).An all-metal sealing technique was adopted to avoid high-voltage breakdown by ensuring a high-voltage connection and an electronic system working in an atmospheric environment.A position resolution of 7.8±0.1 mm(full width at maximum)is measured along the length of the tubes,with a high detection efficiency of 81±2% at 2A.Operating over the past four years,the detector appears to perform well and with a high stability,which supports the SANS instrument to finish approximately 200 user scientific programs.
