Mouth ulcer
A mouth ulcer is a break in the lining of the mouth that exposes underlying tissue. Minor injury and aphthous stomatitis are common causes.
Aphthous stomatitis: A recurrent condition causing painful, shallow ulcers on the nonkeratinized lining of the mouth. It is a common cause of mouth ulcers that are not due to injury.
Wound healing: The biological process that repairs damaged tissue through overlapping stages of inflammation, tissue formation, and remodeling. Most uncomplicated mouth ulcers close as oral tissue repairs the disrupted surface.
Oral examination: Inspection and assessment of the mouth, teeth, gums, tongue, and related tissues. Location, appearance, and number of ulcers guide their evaluation.
Canker sore: A common name for a painful aphthous ulcer inside the mouth. It is the familiar small, shallow ulcer associated with aphthous stomatitis.
Traumatic ulcer: An ulcer caused by physical, chemical, or thermal damage to oral tissue. It accounts for many isolated ulcers after biting, friction, or burns.
Inflammation: A coordinated tissue response to injury or infection involving immune cells and chemical signals. Inflammation around exposed tissue contributes to ulcer pain and redness.
Differential diagnosis: The process of distinguishing among conditions that can produce similar signs or symptoms. Several infections, injuries, and systemic diseases can cause mouth ulcers.
Herpetic gingivostomatitis: An acute herpes simplex virus infection causing painful oral lesions and inflamed gums. Clusters of oral sores with fever and gum inflammation suggest infection rather than an isolated ulcer.
Oral mucosa: The moist lining of the mouth, including its epithelial surface and underlying connective tissue. An ulcer forms when this lining is disrupted.
Nociception: The nervous system's detection and processing of potentially tissue-damaging stimuli. Exposed, inflamed tissue makes contact and chemical stimuli painful.