A collection of purulent exudate at the apex of a nonvital tooth accompanied by pain and fever with potential discharge into the mouth; usually there is no periapical radiolucency; the condition requires pulp extirpation or tooth extraction, incision and drainage, and antibiotic therapy.
Aetiology: Non-vital tooth
Location(s): Either jaw; apex of a non-vital tooth.
Clinical Features: Red, painful swelling; fever and leukocytosis often present
Radiographic Features: Usually no periapical lesion.
Microscopic Features: Acute inflammation.
Complications: Diffuse spread (cellulitis) into neck or brain.
Treatment: Removal of cause, incision and drainage, antibiotic therapy.
Prognosis: Good with cause removal and vigorous therapy.
Pathogenesis: Spreading infection with pyogenic microorganism due to delayed therapy and/or lowered resistance.
A group of conditions in which acute inflammation predominates. They are usually accompanied by pain, swelling, and pus production. Establishment of drainage and appropriate antimicrobial therapy will cure acute inflammatory conditions.
Aetiology: Microbial infection
Location(s): Mucosa or bone
Clinical Features: Pain, swelling, and pus production
Radiographic Features: None; sometimes show a diffuse radiolucency
Microscopic Features: Acute inflammation
Complications: Pain, disseminated infection
Treatment: Incision and drainage plus antibiotic therapy
Prognosis: Good with appropriate therapy
Pathogenesis: Acute inflammatory response to microbes.
An uncommon autoimmune condition that affects only the oral mucous membrane and eyes; it manifests as bullae and ulcers, has a distinctive histology, and runs a benign course; improvement usually occurs with anti-inflammatory medication; unlike pemphigus, it is not fatal. Aetiology: Autoimmune Location(s): Oral mucosa Clinical Features: Presence of gingival bullae that soon rupture leaving a slough covering a shallow ulcer; may also affect the eyes. Radiographic Features: None Microscopic Features: "Subepithelial clefting" is characteristic. Complications: Eye involvement may lead to blindness Treatment: Corticosteroid therapy Prognosis: Good with appropriate therapy Pathogenesis: Production of auto antibodies directed against the basement membrane of oral mucosa.
A common benign neoplasm arising from blood vessels manifesting as flat or raised red-purple surface discoloration; cosmetic requirements may warrant attempted removal of a haemangioma.
Aetiology: Developmental
Location(s): Anywhere on mucous membrane or within bone
Clinical Features: Flat or raised red lesion that may blanch under pressure
Radiographic Features: If within bone, appears as ill-defined radiolucency
Microscopic Features: Blood vessels filled with RBC's
Complications: haemorrhage
Treatment: Surgical excision (small); produce scarring with chemicals or lasers
Prognosis: Good
Pathogenesis: Unknown; many seem to be inherited
An uncommon benign neoplasm or hamartoma arising from lymphatic vessels manifesting as a raised, soft, shaggy, bubbly, pinkish-white lesion; cosmetic considerations may warrant attempted removal of lymphangiomas.
Aetiology: Developmental
Location(s): Anywhere on mucous membrane; tongue, cheek most common sites
Clinical Features: Raised, diffuse, bubbly, or shaggy lesions of the same colour or lighter than surrounding mucosa
Radiographic Features: None
Microscopic Features: Many lymphatic vessels filled with lymph
Complications: May be difficult to remove entirely; tend to recur
Treatment: Surgical excision or produce scarring with chemicals or lasers
Prognosis: Good
Pathogenesis: Unknown
A rare true soft tissue cyst appearing as a facial swelling of the upper lip and the side of the nose; surgical removal will cure this cyst.
Aetiology: Entrapped embryonic epithelium in the developmental fissures between lateral nasal and maxillary processes
Location(s): Upper lip and side of nose
Clinical Features: Asymptomatic swelling of upper lip and side of nose
Radiographic Features: None; can be visualized with injection of radiopaque dye
Microscopic Features: A true epithelial-lined soft tissue cyst
Complications: None
Treatment: Surgical removal
Prognosis: Does not recur with complete removal
Pathogenesis: Stimulation of entrapped epithelium
An uncommon benign neoplasm arising from nerve sheath cells manifesting as single or multiple submucosal nodules; it has a characteristic histology; the multiple forms causes disfigurement and may lead to malignant change; surgical excision will cure single neurofibromas.
Aetiology: Developmental
Location(s): Any submucosal or subcutaneous site; may occur within bone too.
Clinical Features: Single or multiple submucosal nodules covered with normal mucosa or skin; sometimes covering skin has "cafe-au-lait"spots.
Radiographic Features: None; rare central bone lesions will produce radiolucency.
Microscopic Features: Not encapsulated; cellular fibrous appearance reminiscent of nerves.
Complications: May recur; multiple forms are disfiguring and may become malignant.
Treatment: Surgical excision for single lesions; treatment not successful for multiple.
Prognosis: Single lesions good; multiple form poor.
Pathogenesis: Unknown for single form; multiple form is inherited.
An acute initial infection with the Herpes simplex virus manifesting with fever, malaise, lymphadenopathy, and vesicles followed by ulcers; no current treatment will rid the patient of HSVI; most HSVI+ patients do not remember or did not experience primary herpetic gingivostomatitis.
Aetiology: Microbial infection with HSV
Location(s): Lips and intraoral mucous membrane
Clinical Features: Fever, malaise, lymphadenopathy. Oral mucosa is red with small blisters that soon burst leaving ulcers behind.
Radiographic Features: None
Microscopic Features: Intraepithelial vesicle; cytology smears may reveal signs of viral infection.
Complications: Rarely may produce fatal encephalitis; recurrence common.
Treatment: None, antiviral drugs (acyclovir) may prevent complications.
Prognosis: Good
Pathogenesis: HSV attacks oral epithelial cells producing blisters (vesicles) within the epithelial lining.
A collection of purulent exudate at the apex of a nonvital tooth accompanied by pain and fever with potential discharge into the mouth; usually there is no periapical radiolucency; the condition requires pulp extirpation or tooth extraction, incision and drainage, and antibiotic therapy.
Aetiology: Non-vital tooth
Location(s): Either jaw; apex of a non-vital tooth.
Clinical Features: Red, painful swelling; fever and leukocytosis often present.
Radiographic Features: Usually no periapical lesion.
Microscopic Features: Acute inflammation.
Complications: Diffuse spread (cellulitis) into neck or brain.
Treatment: Removal of cause, incision and drainage, antibiotic therapy.
Prognosis: Good with cause removal and vigorous therapy.
Pathogenesis: Spreading infection with pyogenic microorganism due to delayed therapy and/or lowered resistance.
A rare harmless benign jaw neoplasm of odontogenic epithelium occurring in children and appearing as a unilocular radiolucency around the crown of an unerupted tooth; surgical excision will cure this neoplasm.
Aetiology: Odontogenic epithelium
Location(s): Anterior maxilla is the most common site.
Clinical Features: May be no clinical features; however, may prevent tooth eruption.
Radiographic Features: Radiolucency around the crown of an unerupted tooth; may be small radiopacities.
Microscopic Features: Well-differentiated epithelial" duct-like" structures; encapsulated.
Complications: None.
Treatment: Surgical excision.
Prognosis: Will not recur with complete excision.
Pathogenesis: Presumed activation of enamel organ epithelium.
An uncommon benign jaw neoplasm of odontogenic epithelium and c.t. occurring in children and appearing as a unilocular radiolucency in tooth-bearing areas; since it does not infiltrate, surgical excision will cure this neoplasm.
Aetiology: Odontogenic epithelium
Location(s): Posterior mandible is the most common location.
Clinical Features: Large lesions may cause jaw expansion;
otherwise, usually there are no clinical features.
Radiographic Features: Unilocular radiolucency; some may
be multilocular.
Microscopic Features: Proliferating "dental papilla-like"mesenchyme
and "enamel organ-like" epithelium.
Complications: Recurrence may occur; recurrent lesions may become sarcomatous.
Treatment: Surgical excision
Prognosis: Good. Complete surgical excision will cure.
Pathogenesis: Presumed activation of both epithelial and mesenchymal components of enamel organ tissues.
An uncommon benign jaw neoplasm of odontogenic epithelium appearing as a unilocular or multilocular radiolucency; because of its locally-infiltrative growth pattern, this neoplasm may be difficult to eradicate.
Aetiology: Odontogenic epithelium
Location(s): Posterior mandible is the most common location.
Clinical Features: Large lesions may cause jaw expansion; otherwise, usually there are no clinical features.
Radiographic Features: Multilocular radiolucency; small lesions can be unilocular.
Microscopic Features: Proliferating epithelial structures resembling" enamel organs."
Complications: Recurrence is common; these lesions are difficult to eradicate.
Treatment: Wide surgical excision.
Prognosis: Complete removal will cure; large lesions may recur.
Pathogenesis: Presumed activation of odontogenic epithelium in rests, in cyst linings, or in the developing enamel organ
A common situation in which epithelial cells within chronic apical periodontitis are stimulated to proliferate with formation of a central cavity; removal of cause and surgical removal will cure this lesion.
Aetiology: Non-vital tooth
Location(s): Either jaw; apex of a non-vital tooth.
Clinical Features: Usually none.
Radiographic Features: Periapical radiolucency.
Microscopic Features: Epithelial-lined central cavity with
chronic inflammation in fibrous c.t. wall.
Complications: Usually none; may produce bone expansion
if large.
Treatment: Removal of cause (pulp extirpation or extraction)
and excision of lesion.
Prognosis: Will not recur with removal of cause.
Pathogenesis: Presumed inflammatory stimulation of epithelial rests of Malassez with formation of central cavity.
A rare malignant neoplasm of chondroblasts appearing as a poorly-demarcated radiolucency; it metastasizes by blood; radical surgery and/or chemotherapy is required; it has a poor prognosis.
Aetiology: Unknown
Location(s): Either jaw; more common in maxilla.
Clinical Features: Jaw swelling with large lesions; may cause unexplained paresthesias.
Radiographic Features: Ill-defined, diffuse radiolucency.
Microscopic Features: Malignant chondroblasts that produce abnormal cartilage.
Complications: Repeated local recurrence; may metastasize too.
Treatment: Radical surgical excision.
Prognosis: Poor; about 17% in jaws.
Pathogenesis: Malignant transformation of chondroblasts
A common condition usually without severe signs or symptoms recognized by a well-defined radiolucency at the apex of a non-vital tooth; its treatment requires endodontics therapy or tooth extraction.
Aetiology: Non-vital tooth
Location(s): Either jaw; apex of a non-vital tooth.
Clinical Features: Usually none
Radiographic Features: Periapical radiolucency
Microscopic Features: Granulation tissue and chronic inflammation
Complications: May recur if antigen source is not eliminated.
Treatment: Will not recur with proper therapy
Prognosis: Removal of antigen source: pulp extirpation with root canal filling or tooth extraction.
Pathogenesis: Continuous antigenic stimulation producing periapical chronic inflammation
A fairly-common condition usually without severe signs of symptoms recognized by a well-defined radiopacity at the apex of a non vital tooth; therapy requires orthodontic therapy or tooth extraction.
Aetiology: Non-vital tooth
Location(s): Either jaw; apex of a non-vital tooth.
Clinical Features: Usually none.
Radiographic Features: Periapical radiopacity
Microscopic Features: Chronic inflammation and bone production.
Complications: None
Treatment: Removal of cause: pulp extirpation or tooth extraction.
Prognosis: Good
Pathogenesis: Stimulation of bone production by chronic inflammation.
A common true epithelial-lined jaw cyst appearing as a radiolucency surrounding the crown of an unerupted or impacted tooth; rarely ameloblastoma will arise in this cyst; surgical excision will cure a dentigerous cyst.
Aetiology: Odontogenic epithelium
Location(s): Either jaw.
Clinical Features: None; may be jaw expansion with large lesions
Radiographic Features: Radiolucent lesion around crown of unerupted tooth.
Microscopic Features: A true epithelial-lined cyst; may be keratinized.
Complications: May recur if keratinized; ameloblastoma may develop.
Treatment: Surgical removal
Prognosis: Does not recur with complete removal
Pathogenesis: Stimulation of odontogenic epithelium
An uncommon, developmental, self-limiting, unilateral fibrosseous condition arising in either jaw; once correctly identified, no treatment is necessary.
Aetiology: Unknown
Location(s): Either jaw; maxilla more common.
Clinical Features: Unilateral asymptomatic jaw swelling; tooth spacing on affected side.
Radiographic Features: Diffuse increase in bone trabeculae;"ground glass" appearance.
Microscopic Features: Proliferating fibrous c.t. stroma and cancellous bone deposition.
Complications: None if treated appropriately.
Treatment: Surgical reduction of jaw expansion; may continue to grow for a time.
Prognosis: Growth slows or stops in adulthood.
Pathogenesis: Developmental proliferation of fibrous c.t. and bone
An uncommon true jaw cyst appearing as a radiolucency between the roots of vital maxillary lateral incisor and cuspid (canine) teeth; surgical removal will cure this cyst; some dispute the origin of this lesion.
Aetiology: Entrapped epithelium
Location(s): Maxilla, anterior, between lateral incisor and cuspids
Clinical Features: None; may be swelling with large lesions
Radiographic Features: Radiolucency between vital lateral incisor and cuspid teeth
Microscopic Features: True epithelial-lined cyst
Complications: None
Treatment: Surgical removal
Prognosis: Does not recur with complete removal
Pathogenesis: Stimulation of entrapped epithelium
A common benign neoplasm arising from blood vessels manifesting as flat or raised red-purple surface discoloration; cosmetic requirements may warrant attempted removal of a haemangioma.
Aetiology: Developmental
Location(s): Anywhere on mucous membrane or within bone
Clinical Features: Flat or raised red lesion that may blanch under pressure
Radiographic Features: If within bone, appears as ill-defined radiolucency
Microscopic Features: Blood vessels filled with RBC's
Complications: Haemorrhage
Treatment: Surgical excision (small); produce scarring with chemicals or lasers
Prognosis: Good
Pathogenesis: Unknown; many seem to be inherited
An ill-defined radiolucency in the mandibular body that, on histologic examination, proves to be filled with normal bone marrow.
Aetiology: Unknown
Location(s): Either jaw; mandible more common site
Clinical Features: None
Radiographic Features: Well-demarcated or ill-defined radiolucency.
Microscopic Features: Normal bone marrow
Complications: None
Treatment: None; biopsy probably needed to establish diagnosis.
Prognosis: Excellent
Pathogenesis: Unknown
A common true jaw cyst appearing as a radiolucency in the maxilla midline just lingual to the central incisor teeth (in the incisive canal); surgical removal will cure this cyst.
Aetiology: Enclave epithelium
Location(s): Maxilla, anterior incisive canal region
Clinical Features: Usually none; may be swelling with large lesions.
Radiographic Features: Radiolucency in midline anterior maxilla.
Microscopic Features: True epithelial-lined cyst; nerves and blood vessels in c.t. wall.
Complications: None
Treatment: Surgical removal
Prognosis: Does not recur with complete removal
Pathogenesis: Stimulation of enclaved epithelium
within the jaws are detected as radiolucencies, radiopacities, or mixed radiolucent/opacities on radiographic examination.
Aetiology: Non-vital tooth or infection; otherwise unknown
Location(s): Mandible or maxilla
Clinical Features: Usually none; large lesions may cause noticable jaw expansion
Radiographic Features: Radiolucencies, radiopacities, or mixed radiolucencies/opacities
Microscopic Features: Depends on lesion: inflammation, neoplasia, or misplaced normal tissue
Complications: Depends on lesion: may be serious (cancer), less serious (periapical lesions), or trivial
Treatment: Depends on lesion: excision for many, observation for some
Prognosis: Depends on lesion
Pathogenesis: Inflammation, neoplasia, or abnormal development
An uncommon true jaw cyst appearing as radiolucency in the maxilla midline posterior to the incisive canal; surgical removal will cure this cyst.
Aetiology: Entrapped epithelium
Location(s): Maxilla, palatal midline
Clinical Features: Usually none; may be swelling with large lesions.
Radiographic Features: Radiolucency in midline of hard palate
.
Microscopic Features: True cyst lined with epithelium.
Complications: None
Treatment: Surgical removal
Prognosis: Does not recur with complete removal
Pathogenesis: Stimulation of enclaved epithelium
Metastatic Jaw Malignancies
Uncommon appearance of unexplained jaw radiolucency that proves, on biopsy, to be composed of malignant cells which are not of oral origin; primary malignancies are often in breast, prostate, kidney, or thyroid; prognosis is grave.
Aetiology: Metastasis
Location(s): Either jaw; more common in mandible.
Clinical Features: None; may be pain.
Radiographic Features: Ill-defined radiolucency.
Microscopic Features: Malignant epithelial (usually) cells; may resemble primary malignancy.
Complications: Indicates wide-spread metastasis.
Treatment: Chemotherapy, radiotherapy
Prognosis: Grave; <10%.
Pathogenesis: Development of metastatic colony from primary malignancy in extra-oral site.
A jaw cyst of dentigerous or primordial origin lined with keratinized epithelium appearing as a radiolucency around the crown of an unerupted tooth (dentigerous) or in a tooth-bearing area unassociated with a tooth (primordial); this cyst may be difficult to remove surgically and therefore may recur.
Aetiology: Odontogenic epithelium
Location(s): Either jaw
Clinical Features: None; may be jaw expansion with large lesions
Radiographic Features: Radiolucency associated or unassociated with a tooth.
Microscopic Features: True epithelial-lined cyst lined by keratinizing epithelium
Complications: May be difficult to remove; they may recur.Treatment: Surgical removalPrognosis: Does not recur with complete removal
Pathogenesis: Stimulation of odontogenic epithelium.
A relatively common benign odontogenic neoplasm producing all dental tissues and appearing as a well-demarcated mostly radiopaque lesion in tooth-bearing areas; surgical excision will cure this lesion.
Aetiology: Odontogenic epithelium
Location(s): Either jaw; maxilla a more common site.
Clinical Features: Usually none; may prevent tooth eruption.
Radiographic Features: Multiple small radiopacities some of which may resemble "small teeth."
Microscopic Features: Collections of all hard and soft dental tissues.
Complications: None.
Treatment: Surgical excision
Prognosis: Complete excision will cure this lesion.
Pathogenesis: Presumed activation of developing dental tissues
A benign, self-limiting fibrosseous condition that is a possible reaction to local injury appearing as radiolucent and radiopaque lesions at the apices of vital teeth; once correctly identified, no therapy is necessary.
Aetiology: Bacterial, Chemical, or Physical Irritation
Location(s): Either jaw; mandible the more common site.
Clinical Features: Asymptomatic; associated teeth are vital.
Radiographic Features: Periapical radiolucencies/opacities.
Microscopic Features: Proliferating fibrous c.t. stroma and cancellous bone deposition.
Complications: None of treated appropriately.
Treatment: None
Prognosis: Excellent; self-limiting.
Pathogenesis: Presumed abnormal reparative reaction of bone to some local injury
A benign neoplasm arising within either jaw appearing as a radiolucent lesion; it has a fibrosseous histology; complete surgical removal will cure this lesion.
Aetiology: Unknown
Location(s): Either jaw; mandible more common site.
Clinical Features: Asymptomatic; large lesion may cause jaw expansion.
Radiographic Features: Well-demarcated radiolucency; may cross midline; may have radiopacities.
Microscopic Features: Proliferating fibrous c.t. stroma and cancellous bone deposition.
Complications: None with appropriate therapy.
Treatment: Surgical removal.
Prognosis: Will not recur with complete removal.
Pathogenesis: Neoplastic proliferation of fibrous c.t. and bone.
A microbial infection of bone marrow of (usually) the mandible accompanied by pain, fever with potential drainage of suppuration into the mouth and ill-defined radiolucencies and, sometimes, ill-defined radiopacities; treatment includes removal of cause, debridement, and vigorous antibiotic therapy.
Aetiology: Non-vital tooth
Location(s): Either jaw; alveolar process and body
Clinical Features: Fever and pain. May be suppuration.
Radiographic Features: Radiolucencies, radiopacities, or both.
Microscopic Features: Acute or chronic inflammation with bone destruction or proliferation.
Complications: Persistent infection, suppuration.
Treatment: Removal of cause, antibiotic therapy, debridement.
Prognosis: May be difficult to eradicate.
Pathogenesis: Extension of infection into jaw; patient may be immunocompromised or immunosuppressed.
An uncommon malignant neoplasm of osteoblasts appearing as a poorly demarcated radiopacity/radiolucency; it metastasizes early by blood; radical surgery is required; it has a poor prognosis.
Aetiology: Unknown
Location(s): Either jaw; mandible more common.
Clinical Features: Jaw swelling with large lesions; often associated with "bone pain."
Radiographic Features: Mainly a diffuse, ill-defined radiopacity; may have radiolucent areas.
Microscopic Features: Malignant osteoblasts that may form spicules of bone.
Complications: Local recurrence and blood-borne metastases.
Treatment: Radical surgical excision; chemotherapy.
Prognosis: Poor; has improved in recent years from 25-60%.
Pathogenesis: Malignant transformation of osteoblasts
An uncommon fibrosseous condition of unknown cause that produces enlargement of the skull and jaws; it has a distinctive radiographic appearance, is difficult to treat, and ultimately may kill.
Aetiology: Unknown
Location(s): Either jaw; maxilla more common site; affects other bones too.
Clinical Features: Enlargement of the maxilla; may have considerable bone pain.
Radiographic Features: Diffuse radiolucency/opacities ("cotton wool"); hypercementosis.
Microscopic Features: Proliferating fibrous c.t. stroma with bone resorption and deposition.
Complications: Osteosarcoma may occur; pain, paresthesia, and dental problems are common.
Treatment: None; alleviate pain and other complications.
Prognosis: Continual enlargement and weakening of bones; osteosarcoma may occur.
Pathogenesis: Resorption and deposition of bone in response to some unknown stimulus.
Residual Cyst
A true cyst inadvertently left behind during extraction of a tooth. May be of apical (inflammatory) or dentigerous (developmental) origin. Surgical removal will cure this lesion.
Aetiology: Iatrogenic
Location(s): Either jaw
Clinical Features: Usually none; may be jaw swelling if very large.
Radiographic Features: Radiolucency
Microscopic Features: True cyst
Complications: None
Treatment: Surgical removal
Prognosis: Will not recur with complete removal
Pathogenesis: Cyst left behind during removal of associated tooth.