Sleep apnea, also spelled sleep apnoea, is a sleep disorder in which pauses in breathing or periods of shallow breathing during sleep occur more often than normal. Each pause can last for a few seconds to a few minutes and they happen many times a night. In the most common form, this follows loud snoring. A choking or snorting sound may occur as breathing resumes. Because the disorder disrupts normal sleep, those affected may experience sleepiness or feel tired during the day. In children, it may cause hyperactivity or problems in school.
Snoring is the vibration of respiratory structures and the resulting sound due to obstructed air movement during breathing while sleeping. The sound may be soft or loud and unpleasant. Snoring during sleep may be a sign, or first alarm, of obstructive sleep apnea (OSA). Research suggests that snoring is one of the factors of sleep deprivation.
The hyoid bone is a horseshoe-shaped bone situated in the anterior midline of the neck between the chin and the thyroid cartilage. At rest, it lies between the base of the mandible and the third cervical vertebra.
Upper airway resistance syndrome (UARS) is a sleep disorder characterized by the narrowing of the airway that can cause disruptions to sleep. The symptoms include unrefreshing sleep, fatigue, sleepiness, chronic insomnia, and difficulty concentrating. UARS can be diagnosed by polysomnograms capable of detecting Respiratory Effort-related Arousals. It can be treated with lifestyle changes, orthodontics, surgery, or CPAP therapy. UARS is considered a variant of sleep apnea, although some scientists and doctors believe it to be a distinct disorder.
Craniometry is measurement of the cranium, usually the human cranium. It is a subset of cephalometry, measurement of the head, which in humans is a subset of anthropometry, measurement of the human body. It is distinct from phrenology, the pseudoscience that tried to link personality and character to head shape, and physiognomy, which tried the same for facial features. However, these fields have all claimed the ability to predict traits or intelligence.
Crouzon syndrome is an autosomal dominant genetic disorder known as a branchial arch syndrome. Specifically, this syndrome affects the first branchial arch, which is the precursor of the maxilla and mandible. Since the branchial arches are important developmental features in a growing embryo, disturbances in their development create lasting and widespread effects.
Polysomnography (PSG), a type of sleep study, is a multi-parameter study of sleep and a diagnostic tool in sleep medicine. The test result is called a polysomnogram, also abbreviated PSG. The name is derived from Greek and Latin roots: the Greek πολύς, the Latin somnus ("sleep"), and the Greek γράφειν.
Craniosynostosis is a condition in which one or more of the fibrous sutures in a young infant's skull prematurely fuses by turning into bone (ossification), thereby changing the growth pattern of the skull. Because the skull cannot expand perpendicular to the fused suture, it compensates by growing more in the direction parallel to the closed sutures. Sometimes the resulting growth pattern provides the necessary space for the growing brain, but results in an abnormal head shape and abnormal facial features. In cases in which the compensation does not effectively provide enough space for the growing brain, craniosynostosis results in increased intracranial pressure leading possibly to visual impairment, sleeping impairment, eating difficulties, or an impairment of mental development combined with a significant reduction in IQ.
A mandibi splint or mandibi advancement splint is a prescription custom-made medical device worn in the mouth used to treat sleep-related breathing disorders including: obstructive sleep apnea (OSA), snoring, and TMJ disorders. These devices are also known as mandibular advancement devices, sleep apnea oral appliances, oral airway dilators, and sleep apnea mouth guards.
Obstructive sleep apnea (OSA) is the most common sleep-related breathing disorder and is characterized by recurrent episodes of complete or partial obstruction of the upper airway leading to reduced or absent breathing during sleep. These episodes are termed "apneas" with complete or near-complete cessation of breathing, or "hypopneas" when the reduction in breathing is partial. In either case, a fall in blood oxygen saturation, a disruption in sleep, or both, may result. A high frequency of apneas or hypopneas during sleep may interfere with the quality of sleep, which – in combination with disturbances in blood oxygenation – is thought to contribute to negative consequences to health and quality of life. The terms obstructive sleep apnea syndrome (OSAS) or obstructive sleep apnea–hypopnea syndrome (OSAHS) may be used to refer to OSA when it is associated with symptoms during the daytime.
Orthognathic surgery, also known as corrective jaw surgery or simply jaw surgery, is surgery designed to correct conditions of the jaw and lower face related to structure, growth, airway issues including sleep apnea, TMJ disorders, malocclusion problems primarily arising from skeletal disharmonies, and other orthodontic dental bite problems that cannot be treated easily with braces, as well as the broad range of facial imbalances, disharmonies, asymmetries, and malproportions where correction may be considered to improve facial aesthetics and self-esteem.
Forensic facial reconstruction is the process of recreating the face of an individual from their skeletal remains through an amalgamation of artistry, anthropology, osteology, and anatomy. It is easily the most subjective—as well as one of the most controversial—techniques in the field of forensic anthropology. Despite this controversy, facial reconstruction has proved successful frequently enough that research and methodological developments continue to be advanced.
Hypopnea is overly shallow breathing or an abnormally low respiratory rate. Hypopnea is defined by some to be less severe than apnea, while other researchers have discovered hypopnea to have a "similar if not indistinguishable impact" on the negative outcomes of sleep breathing disorders. In sleep clinics, obstructive sleep apnea syndrome or obstructive sleep apnea–hypopnea syndrome is normally diagnosed based on the frequent presence of apneas and/or hypopneas rather than differentiating between the two phenomena. Hypopnea is typically defined by a decreased amount of air movement into the lungs and can cause oxygen levels in the blood to drop. It commonly is due to partial obstruction of the upper airway.
Pycnodysostosis, is a lysosomal storage disease of the bone caused by a mutation in the gene that codes the enzyme cathepsin K. It is also known as PKND and PYCD.
Cephalometric analysis is the clinical application of cephalometry. It is analysis of the dental and skeletal relationships of a human skull. It is frequently used by dentists, orthodontists, and oral and maxillofacial surgeons as a treatment planning tool. Two of the more popular methods of analysis used in orthodontology are the Steiner analysis and the Downs analysis. There are other methods as well which are listed below.
Cecil C. Steiner was a dentist and one of Edward H. Angle's first students in 1921. He developed a form of cephalometric analysis, presented in 1953, referred to as the Steiner method of analysis.
Sleep surgery is a surgery performed to treat sleep disordered breathing. Sleep disordered breathing is a spectrum of disorders that includes snoring, upper airway resistance syndrome, and obstructive sleep apnea. These surgeries are performed by surgeons trained in otolaryngology, oral maxillofacial surgery, and craniofacial surgery.
Hyoid suspension, also known as hyoid myotomy and suspension or hyoid advancement, is a surgical procedure or sleep surgery in which the hyoid bone and its muscle attachments to the tongue and airway are pulled forward with the aim of increasing airway size and improving airway stability in the retrolingual and hypopharyngeal airway. The horseshoe shaped hyoid bone sits directly below the base of tongue with the arms of the bone flanking the airway. Hyoid suspension is typically performed as a treatment for obstructive sleep apnea (OSA). This procedure is frequently performed with a uvulopalatopharyngoplasty (UPPP) which targets sites of obstruction higher in the airway. Typically, a hyoid suspension is considered successful when the patient's apnea-hypopnea index is significantly reduced after surgery.
Natural head position is a reproducible position of a head when it is in an upright position, with eyes looking straight at a mark. The concept was introduced into the field of orthodontics in the late 1950s by Moorrees and Kean. A horizontal line related to the natural head position has been recommended as the most reliable plane to study cephalometric analysis.
Human jaw shrinkage is the phenomenon of continued size reduction of the human mandible and maxilla over the past 12,000 to 15,000 years. Modern human lifestyles and diets are vastly different now from what they were for most of human evolutionary history. Human jaws, as well as oral cavities, have been shrinking ever since the Neolithic agricultural revolution. This has been confirmed by bone remains dated to this time period. Researchers are able to infer the basic lifestyle practices of past cultures, enabling them to link jaw size with lifestyle practice/behaviors. Bones from burial sites of past hunter-gatherer societies are associated with larger jaws and mouths, while bones retrieved from former farming cultures have decreased jaw size. Bones from farming societies also indicate the presence of dental malocclusions, commonly known as non-straight teeth. Within recent centuries, as food has become more processed and soft in form, a rapid increase in non-straight teeth, smaller jaws, and mouths; a lack of space for wisdom teeth; and associated health conditions have been observed. Such conditions include sleep apnea, constricted airways, and decreased respiratory fitness. Medical professionals have been making similar observations and documenting them for hundreds of years. Changes in diet, lifestyle, and breathing patterns have led to maladaptive phenotypic expression in terms of morphological craniofacial development that starts in childhood but persists throughout the lifespan.
