Inhalants are a broad range of household and industrial chemicals whose volatile vapors or pressurized gases can be concentrated and breathed in via the nose or mouth to produce intoxication, in a manner not intended by the manufacturer. They are inhaled at room temperature through volatilization (in the case of gasoline or acetone) or from a pressurized container (e.g., nitrous oxide or butane), and do not include drugs that are sniffed after burning or heating. For example, amyl nitrite (poppers), nitrous oxide and toluene – a solvent widely used in contact cement, permanent markers, and certain types of glue – are considered inhalants, but smoking tobacco, cannabis, and crack are not, even though these drugs are inhaled as smoke or vapor.While a few inhalants are prescribed by medical professionals and used for medical purposes, as in the case of inhaled anesthetics and nitrous oxide (an anxiolytic and pain relief agent prescribed by dentists), this article focuses on inhalant use of household and industrial propellants, glues, fuels, and other products in a manner not intended by the manufacturer, to produce intoxication or other psychoactive effects. These products are used as recreational drugs for their intoxicating effect. According to a 1995 report by the National Institute on Drug Abuse, the most serious inhalant use occurs among homeless children and teenagers who "... live on the streets completely without family ties." Inhalants are the only substance used more by younger teenagers than by older teenagers.
When this operation is performed there are several advantages. It is possible to narrow down the velopharyngeal port without modifying the function of the velum or lateral walls. Furthermore, the chance of obstructing the airway is lower, because the port can be closed more precisely. Many materials have been used for this closure: petroleum jelly, paraffin, cartilage, adjacent soft tissue, silastic, fat, Teflon and proplast. But results in the long term are very unpredictable. There are problems with tissue incompatibility and migration of the implant. Even migration to the brain is noticed. Non-operative techniques
Prosthesis
Prostheses are used for nonsurgical closure in a situation of velopharyngeal dysfunction. There are two types of prosthesis: the speech bulb and the palatal lift prosthesis. The speech bulb is an acrylic body that can be placed in the velopharyngeal port and can achieve obstruction. The palatal lift prosthesis is comparable with the speech bulb, but with a metal skeleton attached to the acrylic body. This will also obstruct the velopharyngeal port. It is a good option for patients that have enough tissue but a poor control of the coordination and timing of velopharyngeal movement. It is also used in patients with contraindications for surgery. It has also been used as a reversible test to confirm whether a surgical intervention would help. Etymology
The word velopharyngeal uses combining forms of velo- + pharyng-, referring to the soft palate (velum palatinum) and the pharynx. == References ==