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Ludwig's angina is a fascial space infection with bilateral involvement of the submandibular, sublingual and submental spaces. The external signs may include bilateral lower facial edema around the mandible and upper neck. Intraoral signs may include a raised floor of mouth due to sublingual space involvement and posterior displacement of the tongue. Symptoms may include dysphagia, pain with swallowing, difficulty breathing, and pain.
Ludwig's angina should be treated urgently due to the airway being compromised. The infection may rapidly spread to other fascial spaces of the head and neck, further compromising the airway.
Ludwig's angina, otherwise known as angina ludovici, is a serious, potentially life-threatening cellulitis, or connective tissue infection, of the floor of the mouth, usually occurring in adults with concomitant dental infections and if left untreated, may obstruct the airways, necessitating tracheostomy. It is named after the German physician Wilhelm Friedrich von Ludwig who first described this condition in 1836. Other names include "angina Maligna" and "Morbus Strangularis".
Ludwig's angina should not be confused with "angina pectoris", which is also otherwise commonly known as ""angina"". The word ""angina"" comes from the Greek word ἀγχόνη "ankʰónē", meaning "strangling". In this case, Ludwig's angina refers to the feeling of strangling, not the feeling of chest pain, though there may be chest pain in Ludwig's angina if the infection spreads into the retrosternal space.
The life-threatening nature of this condition generally necessitates surgical management with involvement of critical care physicians such as those found in an intensive care unit.
Acute pericoronitis (i.e. sudden onset and short lived, but significant, symptoms) is defined as "varying degrees of inflammatory involvement of the pericoronal flap and adjacent structures, as well as by systemic complications." Systemic complications refers to signs and symptoms occurring outside of the mouth, such as fever, malaise or swollen lymph nodes in the neck.
Pericoronitis may also be chronic or recurrent, with repeated episodes of acute pericoronitis occurring periodically. Chronic pericoronitis may cause few if any symptoms, but some signs are usually visible when the mouth is examined.
The typical signs and symptoms of cellulitis is an area which is red, hot, and painful. The photos shown here of are of mild to moderate cases, and are not representative of earlier stages of the condition.
Orbital cellulitis
is inflammation of eye tissues behind the orbital septum. It most commonly refers to an acute spread of infection into the eye socket from either the adjacent sinuses or through the blood. It may also occur after trauma.
When it affects the rear of the eye, it is known as retro-orbital cellulitis.
It should not be confused with periorbital cellulitis, which refers to cellulitis anterior to the septum.
Cellulitis is caused by a type of bacteria entering the skin, usually by way of a cut, abrasion, or break in the skin. This break does not need to be visible. Group A "Streptococcus" and "Staphylococcus" are the most common of these bacteria, which are part of the normal flora of the skin, but normally cause no actual infection while on the skin's outer surface.
About 80% of cases of Ludwig's angina, or cellulitis of the submandibular space, are caused by dental infections. Mixed infections, due to both aerobes and anaerobes, are commonly associated with this type of cellulitis. Typically, this includes alpha-hemolytic streptococci, staphylococci, and bacteroides groups.
Predisposing conditions for cellulitis include insect or spider bite, blistering, animal bite, tattoos, pruritic (itchy) skin rash, recent surgery, athlete's foot, dry skin, eczema, injecting drugs (especially subcutaneous or intramuscular injection or where an attempted intravenous injection "misses" or blows the vein), pregnancy, diabetes, and obesity, which can affect circulation, as well as burns and boils, though debate exists as to whether minor foot lesions contribute. Occurrences of cellulitis may also be associated with the rare condition hidradenitis suppurativa or dissecting cellulitis.
The appearance of the skin assists a doctor in determining a diagnosis. A doctor may also suggest blood tests, a wound culture, or other tests to help rule out a blood clot deep in the veins of the legs. Cellulitis in the lower leg is characterized by signs and symptoms similar to those of a deep vein thrombosis, such as warmth, pain, and swelling (inflammation).
This reddened skin or rash may signal a deeper, more serious infection of the inner layers of skin. Once below the skin, the bacteria can spread rapidly, entering the lymph nodes and the bloodstream and spreading throughout the body. This can result in influenza-like symptoms with a high temperature and sweating or feeling very cold with shaking, as the sufferer cannot get warm.
In rare cases, the infection can spread to the deep layer of tissue called the fascial lining. Necrotizing fasciitis, also called by the media "flesh-eating bacteria", is an example of a deep-layer infection. It is a medical emergency.
The signs and symptoms depend upon the type of OM, and may include:
- Pain, which is severe, throbbing and deep seated.
- Initially fistula are not present.
- No dental pain, but headache or other facial pain, as in the descriptive former term "neuralgia-inducing" (cavitational osteonecrosis).
- Fibromyalgia.
- Chronic fatigue syndrome.
- Swelling. External swelling is initially due to inflammatory edema with accompanying erythema (redness), heat and tenderness, and then later may be due to sub-periosteal pus accumulation. Eventually, subperiosteal bone formation may give a firm swelling.
- Trismus (difficulty opening the mouth), which may be present in some cases and is caused by edema in the muscles.
- Dysphagia (difficulty swallowing), which may be present in some cases and is caused by edema in the muscles.
- Cervical lymphadenitis (swelling of the lymph nodes in the neck).
- Aesthesia or paresthesia (altered sensation such as numbness or pins and needles) in the distribution of the mental nerve.
- Fever which may be present in the acute phase and is high and intermittent
- Malaise (general feeling of being unwell) which may be present in the acute phase
- Anorexia (loss of appetite).
- Leukocytosis (elevated numbers of white blood cells) which may be present in the acute phase
- Elevated erythrocyte sedimentation rate and C reactive protein are sometimes present.
- An obvious cause in the mouth (usually) such as a decayed tooth.
- Teeth that are tender to percussion, which may develop as the condition progresses
- Loosening of teeth, which may develop as the condition progresses.
- Pus may later be visible, which exudes from around the necks of teeth, from an open socket, or from other sites within the mouth or on the skin over the involved bone.
- Fetid odor.
Unlike acute OM in the long bones, acute OM in the jaws gives only a moderate systemic reaction and the person remains surprisingly well. Acute OM of the jaws may give a similar appearance to a typical odontogenic infection, but cellulitis does not tend to spread from the periosteal envelope of the involved bone. If the infection is not controlled, the process becomes chronic and systemic symptoms are usually present, including draining fistulas, loosening of teeth and sequestra formation. Untreated chronic osteomyelitis tends to feature occasional acute exacerbations.
The first symptom is a sudden onset of swelling of the face, which develops within two days into papules and pustues on the lips, nose, and around the eyes. These pustules release a purulent discharge, causing a crust to form on the skin. There is also lymphadenopathy (swelling of lymph nodes) in the main lymph nodes of the head. The feet, body, prepuce or perianal area may be affected. Pustular otitis externa can occur, with the pinnae (ear flaps) becoming thickened by edema. Affected areas are painful but not itchy. Approximately half of affected puppies have lethargy and depression. Less common symptoms include pyrexia, anorexia, and joint pain, caused by sterile suppurative arthritis.
The main symptom is pain, which often suddenly appears, is made worse by biting on the involved tooth, which may feel raised and prominent in the bite. The tooth may be mobile, and the lesion may contribute to destruction of the periodontal ligament and alveolar bone. The pain is deep and throbbing. The oral mucosa covering an early periodontal abscess appears erythematous (red), swollen and painful to touch. The surface may be shiny due to stretching of the mucosa over the abscess. Before pus has formed, the lesion will not be fluctuant, and there will be no purulent discharge. There may be regional lymphadenitis.
When pus forms, the pressure increases, with increasing pain, until it spontaneously drains relieving the pain. When pus drains into the mouth, a bad taste is perceived. Usually drainage occurs via the periodontal pocket, or else the infection may spread as a cellulitis or a purulent odontogenic infection. Local anatomic factors determine the direction of spread (see fascial spaces of the head and neck). There may be systemic upset, with malaise and pyrexia.
Common signs and symptoms of orbital cellulitis include pain with eye movement, sudden vision loss, chemosis, bulging of the infected eye, and limited eye movement. Along with these symptoms, patients typically have redness and swelling of the eyelid, pain, discharge, inability to open the eye, occasional fever and lethargy. It is usually caused by a previous sinusitis. Other causes include infection of nearby structures, trauma and previous surgery.
There are four types of abscesses that can involve the periodontal tissues:
1. Gingival abscess—a localized, purulent infection involves only the soft gum tissue near the marginal gingiva or the interdental papilla.
2. Periodontal abscess—a localized, purulent infection involving a greater dimension of the gum tissue, extending apically and adjacent to a periodontal pocket.
3. Pericoronal abscess—a localized, purulent infection within the gum tissue surrounding the crown of a partially or fully erupted tooth. Usually associated with an acute episode of pericoronitis around a partially erupted and impacted mandibular third molar (lower wisdom tooth).
4. combined periodontal/endodontic abscess
Periorbital cellulitis must be differentiated from orbital cellulitis, which is an emergency and requires intravenous (IV) antibiotics. In contrast to orbital cellulitis, patients with periorbital cellulitis do not have bulging of the eye (proptosis), limited eye movement (ophthalmoplegia), pain on eye movement, or loss of vision. If any of these features is present, one must assume that the patient has orbital cellulitis and begin treatment with IV antibiotics. CT scan may be done to delineate the extension of the infection.
Affected individuals may experience the following;
swelling,
redness,
discharge,
pain,
shut eye,
conjunctival injection,
fever (mild), slightly blurred vision, teary eyes, and some reduction in vision.
Typical signs include periorbital erythema, induration, tenderness and warmth.
Toothache, also known as dental pain, is pain in the teeth and/or their supporting structures, caused by dental diseases or pain referred to the teeth by non-dental diseases.
Common causes include inflammation of the pulp, usually in response to tooth decay, dental trauma, or other factors, dentin hypersensitivity (short, sharp pain, usually associated with exposed root surfaces), apical periodontitis (inflammation of the periodontal ligament and alveolar bone around the root apex), dental abscesses (localized collections of pus, such as apical abscess, pericoronal abscess, and periodontal abscess), alveolar osteitis ("dry socket", a possible complication of tooth extraction, with loss of the blood clot and exposure of bone), acute necrotizing ulcerative gingivitis (a gum infection, also called "trenchmouth"), temporomandibular disorder and others.
Pulpitis is classified as reversible when the pain is mild to moderate and lasts for a short time after a stimulus (for instance, cold or sweet); or irreversible when the pain is severe, spontaneous, and lasts a long time after a stimulus. Left untreated, pulpitis may become irreversible, then progress to pulp necrosis (death of the pulp) and apical periodontitis. Abscesses usually cause throbbing pain. The apical abscess usually occurs after pulp necrosis, the pericoronal abscess is usually associated with acute pericoronitis of a lower wisdom tooth, and periodontal abscesses usually represent a complication of chronic periodontitis (gum disease). Much less commonly, non-dental conditions can cause toothache, such as maxillary sinusitis, which can cause pain in the upper back teeth, or angina pectoris, which can cause pain in the lower teeth.
Toothache is the most common type of orofacial pain and, when severe, it is considered a dental emergency, since there may be a significant impact on sleep, eating, and other daily activities. It is one of the most common reasons for emergency dental appointments. Correct diagnosis can sometimes be challenging. The treatment of a toothache depends upon the exact cause, and may involve a filling, root canal treatment, extraction, drainage of pus, or other remedial action. The relief of toothache is considered one of the main responsibilities of dentists. In 2013, 223 million cases of tooth pain occurred as a result of dental caries in permanent teeth and 53 million cases occurred in baby teeth. Historically, the demand for treatment of toothache is thought to have led to the emergence of dental surgery as the first specialty of medicine.
Juvenile cellulitis, also known as puppy strangles or juvenile pyoderma, is an uncommon disease of dogs. Symptoms include dermatitis, lethargy, depression and lameness. When puppies are first presented with what appears to be staphylococcal pyoderma, juvenile cellulitis, a relatively rare condition, may not be considered.
Tuberculous cellulitis is a skin condition resulting from infection with mycobacterium, and presenting as cellulitis.
Signs and symptoms are variable and depend largely upon whether the obstruction of the duct is complete or partial, and how much resultant pressure is created within the gland. The development of infection in the gland also influences the signs and symptoms.
- Pain, which is intermittent, and may suddenly get worse before mealtimes, and then slowly get better (partial obstruction).
- Swelling of the gland, also usually intermittent, often suddenly appearing or increasing before mealtimes, and then slowly going down (partial obstruction).
- Tenderness of the involved gland.
- Palpable hard lump, if the stone is located near the end of the duct. If the stone is near the submandibular duct orifice, the lump may be felt under the tongue.
- Lack of saliva coming from the duct (total obstruction).
- Erythema (redness) of the floor of the mouth (infection).
- Pus discharging from the duct (infection).
- Cervical lymphadenitis (infection).
- Bad Breath.
Rarely, when stones form in the minor salivary glands, there is usually only slight local swelling in the form of a small nodule and tenderness.
The classification is similar to the classification of OM generally, according to the length of time the inflammation has been present and whether there is suppuration (the formation of pus). "Acute osteomyelitis" is loosely defined as OM which has been present for less than one month and "chronic osteomyelitis" is the term used for when the condition lasts for more than one month. Suppurative osteomyelitis of the jaws is uncommon in developed regions, and more common in developing countries. In Europe and the United States, most cases follow dental infections or mandibular fractures. There have been many reported cases occurring in Africa which are coexistent with acute necrotizing ulcerative gingivitis or cancrum oris.
In the pre-antibiotic era, acute OM of the jaws was more extensive. Massive, diffuse infections commonly involved the whole side of the mandible, or the whole of one side and the opposite side as far as the mental foramen. Localized osteomyelitis tended to be described as either "vertical", where a short segment of the body of the mandible from the alveolar crest to the lower border was involved, and "alveolar", where a segment of alveolar bone down to the level of the inferior alveolar canal would sequestrate, including the sockets of several teeth. Treatment with antibiotics has significantly altered the natural history of OM of the jaws. Today, however, the condition is often a hidden infection, due in part to not being visible on most dental X-rays. In addition, some schools of dentistry do not recognize "silent" OM of the jaws—occurrence of the condition without visually obvious manifestations—in their curriculum. In addition, as circulation is intrinsically diminished in jawbones, antibiotics are frequently ineffective.
Non-dental causes of toothache are much less common as compared with dental causes. In a toothache of neurovascular origin, pain is reported in the teeth in conjunction with a migraine. Local and distant structures (such as ear, brain, carotid artery, or heart) can also refer pain to the teeth. Other non-dental causes of toothache include myofascial pain (muscle pain) and angina pectoris (which classically refers pain to the lower jaw). Very rarely, toothache can be psychogenic in origin.
Disorders of the maxillary sinus can be referred to the upper back teeth. The posterior, middle and anterior superior alveolar nerves are all closely associated with the lining of the sinus. The bone between the floor of the maxillary sinus and the roots of the upper back teeth is very thin, and frequently the apices of these teeth disrupt the contour of the sinus floor. Consequently, acute or chronic maxillary sinusitis can be perceived as maxillary toothache, and neoplasms of the sinus (such as adenoid cystic carcinoma) can cause similarly perceived toothache if malignant invasion of the superior alveolar nerves occurs. Classically, sinusitis pain increases upon Valsalva maneuvers or tilting the head forward.
Painful conditions which do not originate from the teeth or their supporting structures may affect the oral mucosa of the gums and be interpreted by the individual as toothache. Examples include neoplasms of the gingival or alveolar mucosa (usually squamous cell carcinoma), conditions which cause gingivostomatitis and desquamative gingivitis. Various conditions may involve the alveolar bone, and cause non-odontogenic toothache, such as Burkitt's lymphoma, infarcts in the jaws caused by sickle cell disease, and osteomyelitis. Various conditions of the trigeminal nerve can masquerade as toothache, including trigeminal zoster (maxillary or mandibular division), trigeminal neuralgia, cluster headache, and trigeminal neuropathies. Very rarely, a brain tumor might cause toothache. Another chronic facial pain syndrome which can mimic toothache is temporomandibular disorder (temporomandibular joint pain-dysfunction syndrome), which is very common. Toothache which has no identifiable dental or medical cause is often termed atypical odontalgia, which, in turn, is usually considered a type of atypical facial pain (or persistent idiopathic facial pain). Atypical odontalgia may give very unusual symptoms, such as pain which migrates from one tooth to another and which crosses anatomical boundaries (such as from the left teeth to the right teeth).
Establishing a diagnosis of nondental toothache is initially done by careful questioning about the site, nature, aggravating and relieving factors, and referral of the pain, then ruling out any dental causes. There are no specific treatments for nondental pain (each treatment is directed at the cause of the pain, rather than the toothache itself), but a dentist can assist in offering potential sources of the pain and direct the patient to appropriate care. The most critical nondental source is the radiation of angina pectoris into the lower teeth and the potential need for urgent cardiac care.
Affected individuals typically develop symptoms including high fevers, shaking, chills, fatigue, headaches, vomiting, and general illness within 48 hours of the initial infection. The erythematous skin lesion enlarges rapidly and has a sharply demarcated, raised edge. It appears as a red, swollen, warm, and painful rash, similar in consistency to an orange peel. More severe infections can result in vesicles (pox or insect bite-like marks), blisters, and petechiae (small purple or red spots), with possible skin necrosis (death). Lymph nodes may be swollen, and lymphedema may occur. Occasionally, a red streak extending to the lymph node can be seen.
The infection may occur on any part of the skin, including the face, arms, fingers, legs, and toes; it tends to favour the extremities. Fat tissue and facial areas, typically around the eyes, ears, and cheeks, are most susceptible to infection. Repeated infection of the extremities can lead to chronic swelling (lymphangitis).
True hyposalivation may give the following signs and symptoms:
- Dental caries (xerostomia related caries) – Without the anticariogenic actions of saliva, tooth decay is a common feature and may progress much more aggressively than it would otherwise ("rampant caries"). It may affect tooth surfaces that are normally spared, e.g., cervical caries and root surface caries. This is often seen in patients who have had radiotherapy involving the major salivary glands, termed radiation-induced caries.
- Acid erosion. Saliva acts as a buffer and helps to prevent demineralization of teeth.
- Oral candidiasis – A loss of the antimicrobial actions of saliva may also lead to opportunistic infection with "Candida" species.
- Ascending (suppurative) sialadenitis – an infection of the major salivary glands (usually the parotid gland) that may be recurrent. It is associated with hyposalivation, as bacteria are able to enter the ductal system against the diminished flow of saliva. There may be swollen salivary glands even without acute infection, possibly caused by autoimmune involvement.
- Dysgeusia – altered taste sensation (e.g., a metallic taste) and dysosmia, altered sense of smell.
- Intraoral halitosis – possibly due to increased activity of halitogenic biofilm on the posterior dorsal tongue (although dysgeusia may cause a complaint of nongenuine halitosis in the absence of hyposalivation).
- Oral dysesthesia – a burning or tingling sensation in the mouth.
- Saliva that appears thick or ropey.
- Mucosa that appears dry.
- A lack of saliva pooling in the floor of the mouth during examination.
- Dysphagia – difficulty swallowing and chewing, especially when eating dry foods. Food may stick to the tissues during eating.
- The tongue may stick to the palate, causing a clicking noise during speech, or the lips may stick together.
- Gloves or a dental mirror may stick to the tissues.
- Fissured tongue with atrophy of the filiform papillae and a lobulated, erythematous appearance of the tongue.
- Saliva cannot be "milked" (expressed) from the parotid duct.
- Difficulty wearing dentures, e.g., when swallowing or speaking. There may be generalized mucosal soreness and ulceration of the areas covered by the denture.
- Mouth soreness and oral mucositis.
- Lipstick or food may stick to the teeth.
- A need to sip drinks frequently while talking or eating.
- Dry, sore, and cracked lips and angles of mouth.
- Thirst.
However, sometimes the clinical findings do not correlate with the symptoms experienced. E.g., a person with signs of hyposalivation may not complain of xerostomia. Conversely a person who reports experiencing xerostomia may not show signs of reduced salivary secretions (subjective xerostomia). In the latter scenario, there are often other oral symptoms suggestive of oral dysesthesia ("burning mouth syndrome"). Some symptoms outside the mouth may occur together with xerostomia.
These include:
- Xerophthalmia (dry eyes).
- Inability to cry.
- Blurred vision.
- Photophobia (light intolerance).
- Dryness of other mucosae, e.g., nasal, laryngeal, and/or genital.
- Burning sensation.
- Itching or grittiness.
- Dysphonia (voice changes).
There may also be other systemic signs and symptoms if there is an underlying cause such as Sjögren's syndrome, for example, joint pain due to associated rheumatoid arthritis.
As a result of radiotherapy to the mouth, radiation-induced stomatitis may develop, which can be associated with mucosal erosions and ulceration. If the salivary glands are irradiated, there may also be xerostomia (dry mouth), making the oral mucosa more vulnerable to frictional damage as the lubricating function of saliva is lost, and mucosal atrophy (thinning), which makes a breach of the epithelium more likely. Radiation to the bones of the jaws causes damage to osteocytes and impairs the blood supply. The affected hard tissues become hypovascular (reduced number of blood vessels), hypocellular (reduced number of cells), and hypoxic (low levels of oxygen). Osteoradionecrosis is the term for when such an area of irradiated bone does not heal from this damage. This usually occurs in the mandible, and causes chronic pain and surface ulceration, sometimes resulting in non-healing bone being exposed through a soft tissue defect. Prevention of osteradionecrosis is part of the reason why all teeth of questionable prognosis are removed before the start of a course of radiotherapy.
Aphthous stomatitis (also termed recurrent aphthous stomatits, RAS, and commonly called "canker sores") is a very common cause of oral ulceration. 10–25% of the general population suffer from this non-contagious condition. The appearance of aphthous stomatitis varies as there are 3 types, namely minor aphthous ulceration, major aphthous ulceration and herpetiform ulceration. Minor aphthous ulceration is the most common type, presenting with 1–6 small (2-4mm diameter), round/oval ulcers with a yellow-grey color and an erythematous (red) "halo". These ulcers heal with no permanent scarring in about 7–10 days. Ulcers recur at intervals of about 1–4 months. Major aphthous ulceration is less common than the minor type, but produces more severe lesions and symptoms. Major aphthous ulceration presents with larger (>1 cm diameter) ulcers that take much longer to heal (10–40 days) and may leave scarring. The minor and major subtypes of aphthous stomatitis usually produce lesions on the non-keratinized oral mucosa (i.e. the inside of the cheeks, lips, underneath the tongue and the floor of mouth), but less commonly major aphthous ulcers may occur in other parts of the mouth on keratinized mucosal surfaces. The least common type is herpetiform ulceration, so named because the condition resembles primary herpetic gingivostomatitis. Herpetiform ulcers begin as small blisters (vesicles) which break down into 2-3mm sized ulcers. Herpetiform ulcers appear in "crops" sometimes hundreds in number, which can coalesce to form larger areas of ulceration. This subtype may cause extreme pain, heals with scarring and may recur frequently.
The exact cause of aphthous stomatitis is unknown, but there may be a genetic predisposition in some people. Other possible causes include hematinic deficiency (folate, vitamin B, iron), stopping smoking, stress, menstruation, trauma, food allergies or hypersensitivity to sodium lauryl sulphate (found in many brands of toothpaste). Aphthous stomatitis has no clinically detectable signs or symptoms outside the mouth, but the recurrent ulceration can cause much discomfort to sufferers. Treatment is aimed at reducing the pain and swelling and speeding healing, and may involve systemic or topical steroids, analgesics (pain killers), antiseptics, anti-inflammatories or barrier pastes to protect the raw area(s).
A ranula usually presents as a translucent blue, dome-shaped, swelling in the tissues of the floor of the mouth. If the lesion is deeper, then there is a greater thickness of tissue separating from the oral cavity and the blue translucent appearance may not be a feature. A ranula can develop into a large lesion many centimeters in diameter, with resultant elevation of the tongue and possibly interfering with swallowing (dysphagia). The swelling is not fixed, may not show blanching and is non-painful unless it becomes secondarily infected. The usual location is usually lateral to the midline, which may be used to help distinguish it from a midline dermoid cyst. A cervical ranula presents as a swelling in the neck, with or without a swelling in the mouth. In common with other mucoceles, ranulas may rupture and then cause recurrent swelling. Ranulas may be asymptomatic, although they can fluctuate rapidly in size, shrinking and swelling, making them hard to detect.
The term is derived from the Greek words "sialon" (saliva) and "lithos" (stone), and the Latin "-iasis" meaning "process" or "morbid condition". A "calculus" (plural "calculi") is a hard, stone-like concretion that forms within an organ or duct inside the body. They are usually made from mineral salts, and other types of calculi include tonsiloliths (tonsil stones) and renal calculi (kidney stones). "Sialolithiasis" refers to the formation of calculi within a salivary gland. If a calculus forms in the duct that drains the saliva from a salivary gland into the mouth, then saliva will be trapped in the gland. This may cause painful swelling and inflammation of the gland. Inflammation of a salivary gland is termed "sialadenitis". Inflammation associated with blockage of the duct is sometimes termed "obstructive sialadenitis". Because saliva is stimulated to flow more with the thought, sight or smell of food, or with chewing, pain and swelling will often get suddenly worse just before and during a meal ("peri-prandial"), and then slowly decrease after eating, this is termed "meal time syndrome". However, calculi are not the only reasons that a salivary gland may become blocked and give rise to the meal time syndrome. Obstructive salivary gland disease, or obstructive sialadenitis, may also occur due to fibromucinous plugs, duct stenosis, foreign bodies, anatomic variations, or malformations of the duct system leading to a mechanical obstruction associated with stasis of saliva in the duct.
Salivary stones may be divided according to which gland they form in. About 85% of stones occur in the submandibular gland, and between 5-10% occur in the parotid gland. In about 0-5% of cases, the sublingual gland or a minor salivary gland is affected. When minor glands are rarely involved, caliculi are more likely in the minor glands of the buccal mucosa and the maxillary labial mucosa. Submandibular stones are further classified as anterior or posterior in relation to an imaginary transverse line drawn between the mandibular first molar teeth. Stones may be radiopaque, i.e. they will show up on conventional radiographs, or radiolucent, where they not be visible on radiographs (although some of their effects on the gland may still be visible). They may also symptomatic or asymptomatic, according to whether they cause any problems or not.