Oral appliance for Obstructive Sleep Apnea: Prototyping and Optimization of the Mandibular Protrusion Device.

Obstructive Sleep apnea is a public health problem. This disease is associated with daytime sleepiness, increased motor vehicle accidents, heart failure and stroke. Treatment options include weight loss, positive airway pressure, pharyngeal and orthognatic surgery. However, selected patients have good response to oral appliances devices that intended to protrude and stabilize the mandible mechanically during the night in order to reduce the collapsibility of the upper airway. Selection of patients includes primary snoring, mild, moderate and positional apnea. The perfect mandibular advance device has not yet been designed. For these reasons, the objective of this paper is to present a new thermoadjustable chair-side oral appliance. Device integrates the best characteristics of custom made and boils and bite previous designs and minimizes inconveniences and possible side effects. The device is a titratable mandibular advancement appliance. It consists of two independent prefabricated trays adaptable to the shape of adult dental arch and linked to each other by a protrusion mechanism. Each tray contains a hard outer shell and a soft thermoplastic resin inner body. The position of the jaw can be adjusted by moving an aluminum rack into, or out from, the guide so the ratchet may get locked into a certain position ensuring the length of the mechanism. The protrusion mechanism is fixed to the splint using small rings that are articulated over a "t" button. Our prototype satisfies the requirements of an effective oral appliance, in terms of retention, comfort, safety and efficacy. It is easy to fit, durable, low cost, quickly titratable, not bulky and easy cleaning. Thermoplastic appliances are specially used like a predictor of treatment response in apnea patients. The device described is a cost-effective introduction to mandibular advancement technology. A qualified dentist or trained sleep doctor could mitigate dental side effects and reduce their incidence.

Analysis and Fem Simulation Methodology of Dynamic Behavior of Human Rotator Cuff in Repetitive Routines: Musician Case Study.

The majority of musculoskeletal injuries located in the shoulder are often due to repetitive or sustained movements that occur in work routines in different areas. In the case of musicians, such as violinists, who have long and daily training routines, the repetitive movements they perform are forced and sometimes the postures are not natural. Therefore, this article aims to study and simulate the dynamic behavior of the glenohumeral joint under repetitive conditions that represent the different postures assumed by a violinist during his daily training. For this purpose, the criteria provided by the RULA (rapid upper limb assessment) method have been used. Subsequently, by using as a reference geometry that of the articulation under study generated and modeled in CATIA®[VERSIÓN 5R21], a FEM analysis has been proposed with the software ANSYS®[VERSIÓN 17.1] simulating the short and cyclic movements of the Humerus of the violinists. With the analysis carried out, thanks to linear and isotropic approximations of the joint, it has been possible to know the approximate dynamic behavior of tissues, muscles and tendons, and the response of the joint in terms of fatigue.