The strain gauge transducers can be used in subjects where bite force of single tooth or group of teeth needs to be recorded. Koc D et al., found that electromyographic activity decreases with an increased jaw opening which may lead to a decreased bite force. Another major disadvantage of strain gauge transducers is that there may be an unavoidable jaw separation caused by the thick metal plate or bite fork used in them. However, using the protective covers may reduce the discomfort to some extent, but it does not help in overcoming the fear associated with biting on the hard surfaces. Hence, several authors have attempted to make biting to be more comfortable by covering the metal surfaces with different materials such as acrylic resin, gutta percha, gauze and polyvinyl chloride. It has been suggested that this is mainly due to discomfort and to the fear of breaking cusps and edges of teeth and dental restorations, when biting on the hard surfaces of the transducers. A potentiometer writer recorded the load on bite plates.Īlthough strain-gauge transducers have been proven to be accurate for the measurement of maximum bite force, it is still difficult to record a true maximum bite force. These plates were attached with strain gauges and the assembly was connected in a Wheatstone bridge circuit. This design consisted of bite plates made from two steel bars, joined by a steel wedge. One such early design was described by Linderholm H and Wennström A. Several designs of these transducers have been described previously. Strain-gauge transducers have been used to record bite force in several studies. This change in voltage can be calibrated with a known weight to indicate the applied load. On loading, these metal plates undergo deformation, due to which its resistance changes, which in turn, results in a change in electric potential or voltage. The strain gauge transducers are devices that consist of a metal plate or fork. These devices use load cells (transducers) to convert force to electrical energy that may be based on one of the following working principles. Most of the devices can record a wide range of force (50-800 N) with accuracy (10 N) and precision (80%). Such devices are both accurate and precise enough for common load measuring purposes. Nowadays, sensitive electronic devices are used in most of the bite force devices. These include the lever-spring, manometer spring and lever, and micrometered devices. Later, several devices were developed some were newly invented while others were modifications and alterations of previous ones. Up to 200 kg weight was raised by the subjects. Subjects were then asked to close the jaw. In this device different weights were attached to a cord that passed over molar teeth of mandible in open position. The first such device was built by Borelli in 1681. The earlier devices, were mechanical in built. This process is experimental and the keywords may be updated as the learning algorithm improves.The bite force devices can either be mechanical or electrical or combination of both. These keywords were added by machine and not by the authors. The most commonly applied are fabricated using quick cure acrylic resin (methyl methacrylate) as either lingual, palatal, or intermaxillary splints. They can be as simple as the patient’s existing acrylic dentures or as complex as custom fabricated casted crowns. Dental splints have been fabricated in many forms and from different materials. During the 1800s, Gunning and Bean devised several types of dental splints, which were secured with an external device. He used a block of ivory, which he attached by wiring it to two holes into the jaw. The use of splints in the treatment of maxillofacial fractures has been part of the plastic surgeons armamentarium since first reported by Bunon (1743). The treatment of maxillofacial fractures has evolved over the years from simple stabilization using external bandages and prolonged immobilization to early mandibular function using craniofacial surgical techniques and rigid fixation.
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