mouth ulcer mouth ulcer a mouth ulcer (aphtha) is an ulcer that occurs on the mucous membrane of the oral cavity. mouth ulcers are very common, occurring in association with many diseases and by many different mechanisms, but usually there is no serious underlying cause. rarely, a mouth ulcer that does not heal may be a sign of oral cancer. these ulcers may form individually or multiple ulcers may appear at once (i.e., a "crop" of ulcers). once formed, an ulcer may be maintained by inflammation and/or secondary infection. "cancer sore" redirects here. not to be confused with canker sore. mouth ulcerother namesoral ulcer, mucosal ulcera mouth ulcer (in this case associated with aphthous stomatitis) on the labial mucosa (lining of the lower lip)specialtyoral medicine the two most common causes of oral ulceration are local trauma (e.g. rubbing from a sharp edge on a broken filling or braces, biting one's lip, etc.) and aphthous stomatitis ("canker sores"), a condition characterized by recurrent formation of oral ulcers for largely unknown reasons. mouth ulcers often cause pain and discomfort and may alter the person's choice of food while healing occurs (e.g. avoiding acidic, sugary, salty or spicy foods and beverages). definition diagramatic representation of mucosal erosion (left), excoriation (center), and ulceration (right) an ulcer (/ˈʌlsər/; from latin ulcus, "ulcer, sore") is a break in the skin or mucous membrane with loss of surface tissue and the disintegration and necrosis of epithelial tissue. a mucosal ulcer is an ulcer which specifically occurs on a mucous membrane. an ulcer is a tissue defect which has penetrated the epithelial-connective tissue border, with its base at a deep level in the submucosa, or even within muscle or periosteum. an ulcer is a deeper breach of epithelium compared to an erosion or excoriation, and involves damage to both epithelium and lamina propria. an erosion is a superficial breach of the epithelium, with little damage to the underlying lamina propria. a mucosal erosion is an erosion which specifically occurs on a mucous membrane. only the superficial epithelial cells of the epidermis or of the mucosa are lost, and the lesion can reach the depth of the basement membrane. erosions heal without scar formation. excoriation is a term sometimes used to describe a breach of the epithelium which is deeper than an erosion but shallower than an ulcer. this type of lesion is tangential to the rete pegs and shows punctiform (small pinhead spots) bleeding, caused by exposed capillary loops. causes ulcers and erosions can be the result of a spectrum of conditions including: those causing auto-immune epithelial damage, damage because of an immune defect (e.g., hiv, leukemia) infections (e.g. herpes viruses) nutritional disorders (e.g., vitamin deficiencies). chemicals such as sls (a common ingredient in many toothpastes) have been linked to mouth ulcers, and have been recognized by public health agencies such as the nhs as a risk factor. injuries (e.g. biting of the lip, tongue, and cheek, hard foods can scrape the oral tissues, hot foods can cause burns) stress: when the body is stressed, the immune symptom may trigger mouth sores pathophysiology the exact pathogenesis is dependent upon the cause. simple mechanisms which predispose the mouth to trauma and ulceration are xerostomia (dry mouth – as saliva usually lubricates the mucous membrane and controls bacterial levels) and epithelial atrophy (thinning, e.g., after radiotherapy), making the lining more fragile and easily breached.: 7 stomatitis is a general term meaning inflammation within the mouth, and often may be associated with ulceration. pathologically, the mouth represents a transition between the gastrointestinal tract and the skin, meaning that many gastrointestinal and cutaneous conditions can involve the mouth. some conditions usually associated with the whole gastrointestinal tract may present only in the mouth, e.g., orofacial granulomatosis/oral crohn's disease. similarly, cutaneous (skin) conditions can also involve the mouth and sometimes only the mouth, sparing the skin. the different environmental conditions (saliva, thinner mucosa, trauma from teeth and food) mean that some cutaneous disorders which produce characteristic lesions on the skin produce only nonspecific lesions in the mouth. the vesicles and bullae of blistering mucocutaneous disorders progress quickly to ulceration in the mouth, because of moisture and trauma from food and teeth. the high bacterial load in the mouth means that ulcers may become secondarily infected. cytotoxic drugs administered during chemotherapy target cells with fast turnovers such as malignant cells. however, the epithelia of the mouth also has a high turnover rate and makes oral ulceration (mucositis) a common side effect of chemotherapy. erosions, which involve the epithelial layer, are red in appearance since the underlying lamina propria shows through. when the full thickness of the epithelium is penetrated (ulceration), the lesion becomes covered with a fibrinous exudate and takes on a yellow-grey color. because an ulcer is a breach of the normal lining, when seen in cross section, the lesion is a crater. a "halo" may be present, which is a reddening of the surrounding mucosa and is caused by inflammation. there may also be edema (swelling) around the ulcer. chronic trauma may produce an ulcer with a keratotic (white, thickened mucosa) margin. malignant lesions may ulcerate either because the tumor infiltrates the mucosa from adjacent tissues, or because the lesion originates within the mucosa itself, and the disorganized growth leads to a break in the normal architecture of the lining tissues. repeat episodes of mouth ulcers can be indicative of an immunodeficiency, signaling low levels of immunoglobulin in the oral mucous membranes. chemotherapy, hiv, and mononucleosis are all causes of immunodeficiency/immunosuppression with which oral ulcers may become a common manifestation. autoimmunity is also a cause of oral ulceration. mucous membrane pemphigoid, an autoimmune reaction to the epithelial basement membrane, causes desquamation/ulceration of the oral mucosa. numerous aphthous ulcers could be indicative of an inflammatory autoimmune disease called behçet's disease. this can later involve skin lesions and uveitis in the eyes. vitamin c deficiency may lead to scurvy which impairs wound healing, which can contribute to ulcer formation. for a detailed discussion of the pathophysiology of aphthous stomatitis, see aphthous stomatitis#causes. diagnostic diagnosis of mouth ulcers usually consists of a medical history followed by an oral examination as well as examination of any other involved area. the following details may be pertinent: the duration that the lesion has been present, the location, the number of ulcers, the size, the color and whether it is hard to touch, bleeds or has a rolled edge. as a general rule, a mouth ulcer that does not heal within 2 or 3 weeks should be examined by a health care professional who is able to rule out oral cancer (e.g. a dentist, oral physician, oral surgeon, or maxillofacial surgeon). if there have been previous ulcers that have healed, then this again makes cancer unlikely. an ulcer that keeps forming on the same site and then healing may be caused by a nearby sharp surface, and ulcers that heal and then recur at different sites are likely to be ras. malignant ulcers are likely to be single in number, and conversely, multiple ulcers are very unlikely to be oral cancer. the size of the ulcers may be helpful in distinguishing the types of ras, as can the location (minor ras mainly occurs on non-keratinizing mucosa, major ras occurs anywhere in the mouth or oropharynx). induration, contact bleeding and rolled margins are features of a malignant ulcer. there may be nearby causative factor, e.g. a broken tooth with a sharp edge that is traumatizing the tissues. otherwise, the person may be asked about problems elsewhere, e.g. ulceration of the genital mucous membranes, eye lesions or digestive problems, swollen glands in neck (lymphadenopathy) or a general unwell feeling. the diagnosis comes mostly from the history and examination, but the following special investigations may be involved: blood tests (vitamin deficiency, anemia, leukemia, epstein-barr virus, hiv infection, diabetes) microbiological swabs (infection), or urinalysis (diabetes). a biopsy (minor procedure to cut out a small sample of the ulcer to look at under a microscope) with or without immunofluorescence may be required, to rule out cancer, but also if a systemic disease is suspected. ulcers caused by local trauma are painful to touch and sore. they usually have an irregular border with erythematous margins and the base is yellow. as healing progresses, a keratotic (thickened, white mucosa) halo may occur.: 52 differential diagnosis due to various factors (saliva, relative thinness of oromucosa, trauma from teeth, chewing, etc.), vesicles and bullae which form on the mucous membranes of the oral cavity tend to be fragile and quickly break down to leave ulcers. aphthous stomatitis and local trauma are very common causes of oral ulceration; the many other possible causes are all rare in comparison. traumatic ulceration a "crop" of trauma-induced ulcers on the labial mucosa most mouth ulcers that are not associated with recurrent aphthous stomatitis are caused by local trauma. the mucous membrane lining of the mouth is thinner than the skin, and easily damaged by mechanical, thermal (heat/cold), chemical, or electrical means, or by irradiation. mechanical a small ulcer on the frenum on the lower inside lip common causes of oral ulceration include rubbing on sharp edges of teeth, fillings, crowns, false teeth (dentures), or braces (orthodontic appliances), or accidental biting caused by a lack of awareness of painful stimuli in the mouth (e.g., following local anesthetic used during dental treatment, which the person becomes aware of as the anesthetic wears off). eating hard foods (e.g., potato chips) can damage the lining of the mouth. some people cause damage inside their mouths themselves, either through an absentminded habit or as a type of deliberate self-harm (factitious ulceration). examples include biting the cheek, tongue, or lips, or rubbing a fingernail, pen, or toothpick inside the mouth. tearing (and subsequent ulceration) of the upper labial frenum may be a sign of child abuse (non-accidental injury). iatrogenic ulceration can also occur during dental treatment, where incidental abrasions to the soft tissues of the mouth are common. some dentists apply a protective layer of petroleum jelly to the lips before carrying out dental work to minimize this. the lingual frenum is also vulnerable to ulceration by repeated friction during oral sexual activity ("cunnilingus tongue"). rarely, infants can ulcerate the tongue or lower lip with the teeth, termed riga-fede disease. thermal and electrical burn thermal burns usually result from placing hot food or beverages in the mouth. this may occur in those who eat or drink before a local anesthetic has worn off. the normal painful sensation is absent and a burn may occur. microwave ovens sometimes produce food that is cold externally and very hot internally, and this has led to a rise in the frequency of intra-oral thermal burns. thermal food burns are usually on the palate or posterior buccal mucosa, and appear as zones of erythema and ulceration with necrotic epithelium peripherally. electrical burns more commonly affect the oral commissure (corner of the mouth). the lesions are usually initially painless, charred and yellow with little bleeding. swelling then develops and by the fourth day following the burn the area becomes necrotic and the epithelium sloughs off. electrical burns in the mouth are usually caused by chewing on live electrical wiring (an act that is relatively common among young children). saliva acts as a conducting medium and an electrical arc flows between the electrical source and the tissues, causing extreme heat and possible tissue destruction. chemical injury caustic chemicals may cause ulceration of the oral mucosa if they are of strong-enough concentration and in contact for a sufficient length of time. the holding of medication in the mouth instead of swallowing it occurs mostly in children, those under psychiatric care, or simply because of a lack of understanding. holding an aspirin tablet next to a painful tooth in an attempt to relieve pulpitis (toothache) is common, and leads to epithelial necrosis. chewable aspirin tablets should be swallowed, with the residue quickly cleared from the mouth. other caustic medications include eugenol and chlorpromazine. hydrogen peroxide, used to treat gum disease, is also capable of causing epithelial necrosis at concentrations of 1–3%. silver nitrate, sometimes used for pain relief from aphthous ulceration, acts as a chemical cauterant and destroys nerve endings, but the mucosal damage is increased. phenol is used during dental treatment as a cavity