|Head and neck|
|A closed human female mouth|
|Latin||os, cavitas oralis|
In addition to its primary role as the beginning of the digestive system, in humans the mouth also plays a significant role in communication. While primary aspects of the voice are produced in the throat, the tongue, lips, and jaw are also needed to produce the range of sounds included in human language.
Mouth cavity 
The first space of the mouth is the mouth cavity, bounded laterally and in front by the alveolar process (containing the teeth), posteriorily by the isthmus of the fauces, superiorly or the roof is formed by hard palate and soft palate and inferiorly or the floor of the mouth is formed by the mylohyoid muscles and is occupied mainly by the tongue. The oral cavity is also known as the mouth which swallows food that then goes down the esophagus and into the stomach.
While shut, the orifice of the mouth forms a line between the upper and lower lip. In facial expression, this mouth line is iconically shaped like an up-open parabola in a smile, and like a down-open parabola in a frown. A down-turned mouth means a mouth line forming a down-turned parabola, and when permanent can be normal. Also, a down-turned mouth can be part of the presentation of Prader-Willi syndrome.
The philtrum is the vertical groove in the upper lip, formed where the nasomedial and maxillary processes meet during embryo development. When these processes fail to fuse fully, a hare lip and/or cleft palate can result. This can result in the encouraging process of the release of metabolic wastes.
The nasolabial folds are the deep creases of tissue that extend from the nose to the sides of the mouth. One of the first signs of age on the human face is the increase in prominence of the nasolabial folds.
Cultural aspects 
Lips can be adorned with lipstick or lip gloss, although in most cultures, this is typically only practiced by females. Both men and women, however, apply lip balm in order to soothe chapped or dry lips.
Oral sex is a form of sexual intercourse practiced with the mouth.
Kisses are performed using the mouth.
Additional Images 
See also 
- Head and neck anatomy
- Mouth breathing
- Index of oral health and dental articles
- List of basic dentistry topics
- Maton, Anthea; Jean Hopkins, Charles William McLaughlin, Susan Johnson, Maryanna Quon Warner, David LaHart, Jill D. Wright (1993). Human Biology and Health. Englewood Cliffs, New Jersey, USA: Prentice Hall. ISBN 0-13-981176-1.
- Cassidy, Suzanne B.; Dykens, Elisabeth; Williams, Charles A. (2000). "Prader-Willi and Angelman syndromes: Sister imprinted disorders". American Journal of Medical Genetics 97 (2): 136–46. doi:10.1002/1096-8628(200022)97:2<136::AID-AJMG5>3.0.CO;2-V. PMID 11180221.