Liquid-crystal displayA liquid-crystal display (LCD) is a flat-panel display or other electronically modulated optical device that uses the light-modulating properties of liquid crystals combined with polarizers. Liquid crystals do not emit light directly but instead use a backlight or reflector to produce images in color or monochrome. LCDs are available to display arbitrary images (as in a general-purpose computer display) or fixed images with low information content, which can be displayed or hidden: preset words, digits, and seven-segment displays (as in a digital clock) are all examples of devices with these displays.
BruxismBruxism is excessive teeth grinding or jaw clenching. It is an oral parafunctional activity; i.e., it is unrelated to normal function such as eating or talking. Bruxism is a common behavior; reports of prevalence range from 8% to 31% in the general population. Several symptoms are commonly associated with bruxism, including aching jaw muscles, headaches, hypersensitive teeth, tooth wear, and damage to dental restorations (e.g. crowns and fillings). Symptoms may be minimal, without patient awareness of the condition.
Temporomandibular joint dysfunctionTemporomandibular joint dysfunction (TMD, TMJD) is an umbrella term covering pain and dysfunction of the muscles of mastication (the muscles that move the jaw) and the temporomandibular joints (the joints which connect the mandible to the skull). The most important feature is pain, followed by restricted mandibular movement, and noises from the temporomandibular joints (TMJ) during jaw movement. Although TMD is not life-threatening, it can be detrimental to quality of life; this is because the symptoms can become chronic and difficult to manage.
OverjetOverjet is the extent of horizontal (anterior-posterior) overlap of the maxillary central incisors over the mandibular central incisors. In class II (division I) malocclusion the overjet is increased as the maxillary central incisors are protruded. Class II Division I is an incisal classification of malocclusion where the incisal edge of the mandibular incisors lie posterior to the cingulum plateau of the maxillary incisors with normal or proclined maxillary incisors (British Standards Index, 1983).
Dental traumaDental trauma refers to trauma (injury) to the teeth and/or periodontium (gums, periodontal ligament, alveolar bone), and nearby soft tissues such as the lips, tongue, etc. The study of dental trauma is called dental traumatology. Dental injuries include: Enamel infraction Enamel fracture Enamel-dentine fracture Enamel-dentine fracture involving pulp exposure Root fracture of tooth Concussion (bruising) Subluxation of the tooth (tooth knocked loose) Luxation of the tooth (displaced) Extrusive Intrusive Lateral Avulsion of the tooth (tooth knocked out) This injury involves the alveolar bone and may extend beyond the alveolus.
Capacitive sensingIn electrical engineering, capacitive sensing (sometimes capacitance sensing) is a technology, based on capacitive coupling, that can detect and measure anything that is conductive or has a dielectric constant different from air. Many types of sensors use capacitive sensing, including sensors to detect and measure proximity, pressure, position and displacement, force, humidity, fluid level, and acceleration. Human interface devices based on capacitive sensing, such as touchpads, can replace the computer mouse.
Flat-panel displayA flat-panel display (FPD) is an electronic display used to display visual content such as text or images. It is present in consumer, medical, transportation, and industrial equipment. Flat-panel displays are thin, lightweight, provide better linearity and are capable of higher resolution than typical consumer-grade TVs from earlier eras. They are usually less than thick. While the highest resolution for consumer-grade CRT televisions was 1080i, many flat-panel displays in the 2020s are capable of 1080p and 4K resolution.
Loading coilA loading coil or load coil is an inductor that is inserted into an electronic circuit to increase its inductance. The term originated in the 19th century for inductors used to prevent signal distortion in long-distance telegraph transmission cables. The term is also used for inductors in radio antennas, or between the antenna and its feedline, to make an electrically short antenna resonant at its operating frequency. The concept of loading coils was discovered by Oliver Heaviside in studying the problem of slow signalling speed of the first transatlantic telegraph cable in the 1860s.
Dipole antennaIn radio and telecommunications a dipole antenna or doublet is the simplest and most widely used class of antenna. The dipole is any one of a class of antennas producing a radiation pattern approximating that of an elementary electric dipole with a radiating structure supporting a line current so energized that the current has only one node at each end. A dipole antenna commonly consists of two identical conductive elements such as metal wires or rods.