ABOP Diplomate key terms

A developmental cyst of the jaws lined by a thin, parakeratinized stratified squamous epithelium with a corrugated surface and palisaded basal layer. It tends to grow along bone with high recurrence after incomplete removal.

A benign but locally aggressive epithelial odontogenic tumor composed of odontogenic epithelium in fibrous stroma, often with peripheral palisading and reverse polarity. Common patterns include follicular, plexiform, and unicystic variants.

A benign, often encapsulated odontogenic tumor of young patients, typically in the anterior maxilla, forming duct-like spaces and rosettes of columnar epithelial cells within a scant fibrous stroma.

A group of reactive fibro-osseous lesions arising in tooth-bearing jaw bone, showing replacement of bone by fibrous tissue and calcified deposits. Variants include periapical, focal, and florid forms, often in middle-aged women.

A benign fibro-osseous developmental lesion in which normal bone is replaced by fibrous tissue containing irregular woven bone trabeculae, producing bone expansion. It may affect one bone or several and can be associated with endocrine syndromes.

A benign fibro-osseous neoplasm of the jaws that is well demarcated and composed of fibrous stroma with varying amounts of bone and cementum-like material. It usually expands bone and is treated by enucleation.

A malignant bone-forming tumor arising in jaw bone, showing atypical cells producing osteoid. It often presents with swelling, pain, and tooth mobility and requires correlation of radiographs and histology.

The most common benign salivary gland tumor, composed of mixed epithelial and myoepithelial cells in a stroma that may be myxoid, chondroid, or hyaline. It is well circumscribed but can recur if incompletely excised.

A malignant salivary gland tumor containing squamous cells, mucus-secreting cells, and intermediate cells, often with cystic spaces. It is the most common salivary malignancy and is graded by architecture and cytologic atypia.

A malignant salivary gland tumor with a cribriform, tubular, or solid growth pattern of basaloid cells. It has a propensity for perineural invasion and late distant metastasis, often to the lungs.

Spread of tumor cells along or around a nerve sheath, seen in several head and neck malignancies including salivary and squamous carcinomas. It indicates aggressive behavior and influences treatment planning.

A malignant epithelial neoplasm with squamous differentiation, showing keratinization, intercellular bridges, and invasive growth. In the head and neck it commonly arises from mucosa and is linked to tobacco, alcohol, and some viral exposures.

A clinical term for a predominantly white patch or plaque of oral mucosa that cannot be characterized clinically or pathologically as any other disease. Diagnosis requires exclusion of other causes and often biopsy.

A clinical term for a red patch of oral mucosa that cannot be attributed to another recognizable condition. It carries a high risk of dysplasia or carcinoma and warrants biopsy.

Disordered maturation and cytologic atypia of epithelium, graded as mild, moderate, or severe. In oral mucosa it is a risk marker for progression to squamous cell carcinoma.

A chronic immune-mediated mucocutaneous disease with white reticulated striae, erosions, or plaques, often bilateral on the buccal mucosa. Histology shows a band-like lymphocytic infiltrate at the epithelial-connective tissue junction.

A pattern of inflammation in which lymphocytes concentrate along the junction between epithelium and connective tissue, with damage to basal cells. It is seen in lichen planus and some other mucocutaneous conditions.

An autoimmune blistering disease caused by antibodies against desmogleins, producing intraepithelial acantholysis and fragile oral blisters or erosions. Direct immunofluorescence shows intercellular deposits.

An autoimmune subepithelial blistering disease affecting mucosa, caused by antibodies to basement membrane components. It may cause scarring and can involve the conjunctiva, so prompt diagnosis matters.

Loss of cohesion between epithelial cells, leading to rounded, separated cells and intraepithelial spaces or blisters. It is a key microscopic feature of pemphigus vulgaris.

Epithelium derived from remnants of the dental lamina, reduced enamel epithelium, rests of Malassez, or rests of Serres. It is the source of many cysts and tumors of the jaws.

An inherited syndrome with multiple odontogenic keratocysts, basal cell carcinomas, palmar pits, and skeletal anomalies. It is linked to mutations in a hedgehog pathway gene.

A sporadic syndrome characterized by polyostotic fibrous dysplasia, irregular skin pigmentation, and endocrine overactivity. It results from a postzygotic activating mutation.

Unmineralized bone matrix produced by osteoblasts. Its presence, especially when made by atypical cells, is a defining feature of osteosarcoma.

A contractile cell lying between glandular epithelium and basement membrane, with both epithelial and smooth muscle features. It contributes to salivary tumors such as pleomorphic adenoma.

A technique using antibodies tagged with a detectable label to identify specific proteins in tissue sections. It helps classify tumors and determine cell lineage in diagnostic pathology.

A family of intermediate filament proteins found in epithelial cells, used in immunohistochemistry to confirm epithelial lineage or specific differentiation patterns in tumors.

A nuclear protein expressed in proliferating cells and detected by immunohistochemistry. Its labeling index estimates tumor proliferation and can inform prognosis or grading.

The proportion of truly affected individuals whom a test correctly identifies as positive. It reflects a test's ability to detect disease and depends on the chosen cutoff.

The proportion of unaffected individuals whom a test correctly identifies as negative. It reflects a test's ability to exclude disease.

The probability that a person with a positive test result actually has the condition. It depends on test sensitivity, specificity, and the prevalence of the disease in the population.

A range of values calculated from sample data that is likely to contain the true population parameter at a stated probability level, commonly 95 percent. It expresses precision of an estimate.

The probability of observing a result at least as extreme as the study data if the null hypothesis were true. It is not the probability that the null hypothesis is true.

A structured, protocol-driven summary of all relevant studies addressing a focused question, using explicit search and selection methods. It may include meta-analysis to pool results.

A statistical method that combines quantitative results from multiple studies to produce a pooled estimate of effect. It increases precision but depends on study quality and heterogeneity.

A ranking of study designs by their susceptibility to bias, from randomized trials and systematic reviews at the top to case reports and expert opinion at the bottom. It guides clinical decision-making.

An external quality assessment in which a laboratory analyzes unknown specimens and compares results with peer laboratories or a reference method. It verifies analytic performance and supports accreditation.

Internal laboratory procedures that monitor test performance against defined limits, such as running control materials with patient samples. Failures trigger investigation before results are reported.

Formal recognition that a laboratory meets externally defined standards for quality and competence, granted after assessment by an authorized body. It is distinct from licensure and certification.