In electrical engineering, ground or earth may be a reference point in an electrical circuit from which voltages are measured, a common return path for electric current, or a direct physical connection to the Earth.
Electrical impedance tomography (EIT) is a noninvasive type of medical imaging in which the electrical conductivity, permittivity, and impedance of a part of the body is inferred from surface electrode measurements and used to form a tomographic image of that part. Electrical conductivity varies considerably among various biological tissues or the movement of fluids and gases within tissues. The majority of EIT systems apply small alternating currents at a single frequency, however, some EIT systems use multiple frequencies to better differentiate between normal and suspected abnormal tissue within the same organ.
Endodontics is the dental specialty concerned with the study and treatment of the dental pulp.
The pulp is the connective tissue, nerves, blood vessels, and odontoblasts that comprise the innermost layer of a tooth. The pulp's activity and signalling processes regulate its behaviour.
A Coulter counter is an apparatus for counting and sizing particles suspended in electrolytes. The Coulter counter is the commercial term for the technique known as resistive pulse sensing or electrical zone sensing. The apparatus is based on the Coulter principle named after its inventor, Wallace H. Coulter.
Electrosurgery is the application of a high-frequency alternating polarity, electrical current to biological tissue as a means to cut, coagulate, desiccate, or fulgurate tissue. Its benefits include the ability to make precise cuts with limited blood loss. Electrosurgical devices are frequently used during surgical operations helping to prevent blood loss in hospital operating rooms or in outpatient procedures.
Bioelectrical impedance analysis (BIA) is a method for estimating body composition, in particular body fat and muscle mass, where a weak electric current flows through the body and the voltage is measured in order to calculate impedance of the body. Most body water is stored in muscle. Therefore, if a person is more muscular there is a high chance that the person will also have more body water, which leads to lower impedance. Since the advent of the first commercially available devices in the mid-1980s the method has become popular owing to its ease of use and portability of the equipment. It is familiar in the consumer market as a simple instrument for estimating body fat. BIA actually determines the electrical impedance, or opposition to the flow of an electric current through body tissues which can then be used to estimate total body water (TBW), which can be used to estimate fat-free body mass and, by difference with body weight, body fat.
A pulp polyp, also known as chronic hyperplastic pulpitis, is a "productive" inflammation of dental pulp in which the development of granulation tissue is seen in response to persistent, low-grade mechanical irritation and bacterial invasion of the pulp.
A post and core crown is a type of dental restoration required where there is an inadequate amount of sound tooth tissue remaining to retain a conventional crown. A post is cemented into a prepared root canal, which retains a core restoration, which retains the final crown.
Root canal treatment is a treatment sequence for the infected pulp of a tooth which is intended to result in the elimination of infection and the protection of the decontaminated tooth from future microbial invasion. Root canals, and their associated pulp chamber, are the physical hollows within a tooth that are naturally inhabited by nerve tissue, blood vessels and other cellular entities. Together, these items constitute the dental pulp.
Apical periodontitis is typically the body's defense response to the threat of microbial invasion from the root canal. Primary among the members of the host defense mechanism is the polymorphonuclear leukocyte, otherwise known as the neutrophil. The task of the neutrophil is to locate and destroy microbes that intrude into the body – anywhere in the body – and they represent the hallmark of acute inflammation.
In dental anatomy, the apical foramen, literally translated "small opening of the apex," is the tooth's natural opening, found at the root's very tip—that is, the root's apex—whereby an artery, vein, and nerve enter the tooth and commingle with the tooth's internal soft tissue, called pulp. Additionally, the apical foramen is the point where the pulp meets the periodontal tissues, the connective tissues that surround and support the tooth.
Pulp necrosis is a clinical diagnostic category indicating the death of the pulp and nerves of the pulp chamber and root canal of a tooth which may be due to bacterial sequelae, trauma and chemical or mechanical irritation. It is often the end result of many cases of dental trauma, caries and irreversible pulpitis.
Endodontic files and reamers are surgical instruments used by dentists when performing root canal treatment. These tools are used to clean and shape the root canal, with the concept being to perform complete chemomechanical debridement of the root canal to the length of the apical foramen. Preparing the canal in this way facilitates the chemical disinfection to a satisfactory length but also provides a shape conducive to obturation.
Apex location is a method of determining the length of the root canal of a tooth - manually or with a mechanical canal instrument that passes a low intensity electric current through the tooth.
As with any material implanted in the body, it is important to minimize or eliminate foreign body response and maximize effectual integration. Neural implants have the potential to increase the quality of life for patients with such disabilities as Alzheimer's, Parkinson's, epilepsy, depression, and migraines. With the complexity of interfaces between a neural implant and brain tissue, adverse reactions such as fibrous tissue encapsulation that hinder the functionality, occur. Surface modifications to these implants can help improve the tissue-implant interface, increasing the lifetime and effectiveness of the implant.
Regenerative endodontic procedures is defined as biologically based procedures designed to replace damaged structures such as dentin, root structures, and cells of the pulp-dentin complex. This new treatment modality aims to promote normal function of the pulp. It has become an alternative to heal apical periodontitis. Regenerative endodontics is the extension of root canal therapy. Conventional root canal therapy cleans and fills the pulp chamber with biologically inert material after destruction of the pulp due to dental caries, congenital deformity or trauma. Regenerative endodontics instead seeks to replace live tissue in the pulp chamber. The ultimate goal of regenerative endodontic procedures is to regenerate the tissues and the normal function of the dentin-pulp complex.
Biofilling, also known as orthograde canal grafting technique or 4D sealing, is an endodontic root canal obturation technique with a Bioceramic material after root canal preparation and enlargement procedure.
Periapical granuloma, also sometimes referred to as a radicular granuloma or apical granuloma, is an inflammation at the tip of a dead (nonvital) tooth. It is a lesion or mass that typically starts out as an epithelial lined cyst, and undergoes an inward curvature that results in inflammation of granulation tissue at the root tips of a dead tooth. This is usually due to dental caries or a bacterial infection of the dental pulp. Periapical granuloma is an infrequent disorder that has an occurrence rate between 9.3 to 87.1 percent. Periapical granuloma is not a true granuloma due to the fact that it does not contain granulomatous inflammation; however, periapical granuloma is a common term used.
Apexification is a method of dental treatment to induce a calcific barrier in a root with incomplete formation or open apex of a tooth with necrotic pulp. Pulpal involvement usually occurs as a consequence of trauma or caries involvement of young or immature permanent teeth. As a sequelae of untreated pulp involvement, loss of pulp vitality or necrotic pulp took place for the involved teeth.
