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Questions and Answers
What is the primary feature of leukoedema as observed histologically?
What is the primary feature of leukoedema as observed histologically?
Which characteristic is consistent with carcinoma in situ?
Which characteristic is consistent with carcinoma in situ?
What is the defining clinical description of erythroleukoplakia?
What is the defining clinical description of erythroleukoplakia?
What are the characteristics of lesions seen in acute lymphonodular pharyngitis?
What are the characteristics of lesions seen in acute lymphonodular pharyngitis?
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What is associated with actinic cheilosis?
What is associated with actinic cheilosis?
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How soon do petechiae on the palate typically disappear?
How soon do petechiae on the palate typically disappear?
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What is a characteristic histologic finding in biopsy specimens of intraoral CMV lesions?
What is a characteristic histologic finding in biopsy specimens of intraoral CMV lesions?
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Which histopathological feature is present in stomatitis nicotina?
Which histopathological feature is present in stomatitis nicotina?
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What is a common histological characteristic of leukoedema?
What is a common histological characteristic of leukoedema?
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Which of the following describes Koplik’s spots?
Which of the following describes Koplik’s spots?
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Which cells are specifically characterized as 'owl eye' cells?
Which cells are specifically characterized as 'owl eye' cells?
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Which layer remains intact in carcinoma in situ?
Which layer remains intact in carcinoma in situ?
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What histological feature may indicate severe dysplasia in erythroleukoplakia?
What histological feature may indicate severe dysplasia in erythroleukoplakia?
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What type of presence does the overlying epithelium show in hyperplastic lymphoid aggregates associated with acute lymphonodular pharyngitis?
What type of presence does the overlying epithelium show in hyperplastic lymphoid aggregates associated with acute lymphonodular pharyngitis?
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What is the main pathological feature identified with Koplik’s spots through histologic examination?
What is the main pathological feature identified with Koplik’s spots through histologic examination?
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What is the characteristic histological feature of Hyperplastic Candidiasis?
What is the characteristic histological feature of Hyperplastic Candidiasis?
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What type of cells were previously thought to be specific to measles before being termed Warthin-Finkeldey giant cells?
What type of cells were previously thought to be specific to measles before being termed Warthin-Finkeldey giant cells?
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Which type of Newton's classification is characterized by pinpoint erythema?
Which type of Newton's classification is characterized by pinpoint erythema?
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Which site is most commonly affected by histoplasmosis?
Which site is most commonly affected by histoplasmosis?
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What aspect differentiates Type II and Type III in Newton's classification?
What aspect differentiates Type II and Type III in Newton's classification?
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What is the most common systemic fungal infection caused by Histoplasma capsulatum?
What is the most common systemic fungal infection caused by Histoplasma capsulatum?
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Which histological feature indicates epithelial dysplasia in candidiasis lesions?
Which histological feature indicates epithelial dysplasia in candidiasis lesions?
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What type of epithelium can be seen in the histological examination of Hyperplastic Candidiasis?
What type of epithelium can be seen in the histological examination of Hyperplastic Candidiasis?
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What clinical feature is most characteristic of ulcerated lesions in histoplasmosis?
What clinical feature is most characteristic of ulcerated lesions in histoplasmosis?
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What is a characteristic histologic feature of gingival fibromatosis?
What is a characteristic histologic feature of gingival fibromatosis?
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Which histologic feature is associated with a gingival abscess?
Which histologic feature is associated with a gingival abscess?
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What is a key histological finding in pericoronitis?
What is a key histological finding in pericoronitis?
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What histological feature is indicative of vitamin C deficiency in the gums?
What histological feature is indicative of vitamin C deficiency in the gums?
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In plasma cell gingivitis, which histological feature is observed?
In plasma cell gingivitis, which histological feature is observed?
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What characteristic feature is observed microscopically in Crohn's disease affecting the oral cavity?
What characteristic feature is observed microscopically in Crohn's disease affecting the oral cavity?
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What type of immune cells predominantly infiltrate the connective tissue in allergic enlargement?
What type of immune cells predominantly infiltrate the connective tissue in allergic enlargement?
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What is a common histologic change seen in the epithelium of an inflamed pericoronal flap?
What is a common histologic change seen in the epithelium of an inflamed pericoronal flap?
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What is the causative microorganism of tuberculosis?
What is the causative microorganism of tuberculosis?
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What is the typical histological feature associated with tuberculosis?
What is the typical histological feature associated with tuberculosis?
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What is a characteristic feature of Snuff dipper lesion?
What is a characteristic feature of Snuff dipper lesion?
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Which of the following is a common oral manifestation of diphtheria?
Which of the following is a common oral manifestation of diphtheria?
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What appearance do the colonies exhibit in actinomycosis?
What appearance do the colonies exhibit in actinomycosis?
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Which of the following is NOT associated with Oral Submucous Fibrosis?
Which of the following is NOT associated with Oral Submucous Fibrosis?
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What is the primary lesion associated with acquired syphilis called?
What is the primary lesion associated with acquired syphilis called?
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Which term describes the fine grayish white lines found in Lichen planus?
Which term describes the fine grayish white lines found in Lichen planus?
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What is a feature of histopathology found in Lichen planus?
What is a feature of histopathology found in Lichen planus?
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What is characteristic of the oral lesions seen in secondary syphilis?
What is characteristic of the oral lesions seen in secondary syphilis?
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In which stage of syphilis do mucous patches typically appear?
In which stage of syphilis do mucous patches typically appear?
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What defines a Lichenoid reaction?
What defines a Lichenoid reaction?
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What type of microorganism is responsible for diphtheria?
What type of microorganism is responsible for diphtheria?
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Which of the following is a common symptom of Lichen planus?
Which of the following is a common symptom of Lichen planus?
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Which histological feature is common in both Snuff dipper lesion and Lichen planus?
Which histological feature is common in both Snuff dipper lesion and Lichen planus?
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What condition is characterized by mucosal rigidity and trismus?
What condition is characterized by mucosal rigidity and trismus?
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Study Notes
Routine Histotechnique and Staining
- Histology is the microscopic study of normal tissues.
- Histology's term originates from Greek, histos meaning tissue, and logy meaning study.
- It was coined by Mayer in 1819.
- Histopathology involves studying structural changes in the body caused by diseases.
- Histotechnology focuses on tissue processing and preparation for a satisfactory study.
- Histotechnique is a branch of biology focused on demonstrating minute tissue structure in diseases.
Introduction to Histotechnique and Staining
- Fixation preserves tissues in a life-like state after removal.
- Formaldehyde-based solutions are typically used.
- Grossing involves isolating the specific tissue area for sectioning.
- Tissue processing involves reagents to replace the aqueous environment with one that facilitates infiltration with wax.
- Embedding allows for specimen orientation and secures the tissue in a wax block for sectioning.
- Sectioning is done on a microtome to cut very thin sections.
- The sections are floated out on a water bath and transferred to microscope slides.
- Different types of fixatives are used depending on the tissue type and what features are needed to be demonstrated.
Fixation
- Fixation is crucial for preserving the tissue.
- It aims to preserve tissues in an unaltered state as closely as possible to their living condition.
- Fixation should occur as quickly as possible after tissue removal to prevent autolysis.
- The choice of fixative depends on the type of tissue and the specific features that need to be demonstrated.
Staining
- Hematoxylin and Eosin (H&E) stain are routine stains.
- It's the first stain applied to tissue sections.
- H&E stains provide diagnostic information in most cases
- Special stains are used to highlight specific tissue components after H&E for more detailed information.
- In H&E, hemato- is a basic dye used to stain basophilic structures, while eosin is an acid dye and stains acidophilic (eosinophilic) structures.
Classification of Stains
- Stains are categorized based on target molecules or structures
- stains for carbohydrates (PAS, Alcian blue)
- stains for amyloid (Congo red)
- stains for nucleic acids (Feulgen)
- stains for lipids (oil red O)
- stains for microorganisms (Ziehl-Neelsen)
- stains for connective tissues (Masson's Trichrome) - stains for pigments and minerals (Perl's stain).
- Periodic acid-Schiff (PAS): stains carbohydrates. The principle is oxidation of vicinal glycol groups to aldehydes before reaction with Schiff's reagent.
- Oil Red O: stains lipids based on the dye's greater solubility in lipid substances than water.
Developmental Disturbances of Oral and Para Oral Structures
- Malformations and defects arise from disturbances during growth and development.
- Manifestations are often present at birth or later.
- Developmental conditions are influenced by genetic and/or environmental factors.
- Anomaly is a medical term meaning 'irregularity' or 'different from normal' affecting craniofacial structures.
- These conditions are usually discovered in childhood or early infancy.
Types of Anomalies/Defects
- Malformation: localized error in the morphogenesis of a structure, often impacting function.
- Deformation: alteration to the shape or structure of a formerly normally formed part.
- Anomaly: a deviation from the normal form or structure without necessarily affecting function.
- Anomalad: refers to a malformation and the subsequent structural changes resulting from it.
Types of Developmental Anomalies
- Congenital: present at birth. Factors include genetic or environmental influences during intrauterine development. Examples include cleft lip and palate.
- Hereditary: genetically transmitted from parents. Genetic location is identified. Example includes Down syndrome (Trisomy 21).
- Familial: transmitted from parents, but definite genetic location is not identified. Examples include diabetes
Acquired Developmental Anomalies
Examples include:
- Congenital syphilis
- Fluoride ingestion resulting in notched incisors, mulberry molars, and enamel hypoplasia.
Developmental Disturbances of Soft Tissue
- Lip pits are frequently bilateral and may be associated with autosomal dominant inheritance.
- Double lip usually happens congenitally.
- Paramedian lip pits can be up to 2cm in depth
Other Oral Anomalies
- Frenal tag- commonly caused by autosomal inheritance
- Fordyce granules - collections of sebaceous glands on the buccal mucosa. They are usually seen as yellow spots.
- Retrocuspid papillae - raised area near the cuspids, with a core of fibrovascular tissue with surface orthokeratinization or parakeratinization.
Micrognathia And Macroglossia
- Micrognathia: a small lower jaw caused by abnormal development of the mandible during fetal development. It can be congenital or acquired.
- Macroglossia: abnormally enlarged tongue. There are causes, like congenital disorders (Down's syndrome, Beckwith- Wiedemann syndrome) or acquired conditions.
Down Syndrome (Trisomy 21)
- The characteristics include a flat face, open sutures, small slanting eyes with epicanthic folds, open mouth, and a high arched palate. It also affects craniofacial structures.
Ankyloglossia (Tongue-Tie)
- Ankyloglossia is a developmental condition where the tongue is abnormally fixed to the floor of the mouth that restricts tongue movement. It can be complete or partial.
- Complete ankyloglossia occurs due to a fusion between the tongue and the floor of the mouth.
- Partial ankyloglossia occurs due to a lingual frenum that attaches too close to the tip of the tongue.
Cleft Tongue / Bifid Tongue
- Complete cleft tongue occurs due to the failure of merging of lateral lingual swellings
- Partial cleft tongue is due to incomplete merging of lingual grooves or failure of groove obliteration during mesenchymal proliferation.
Fissured Tongue / Scrotal Tongue
- Deep fissures may appear in children and adults, often with increased frequency in older subjects.
- It's sometimes observed in conjunction with Down syndrome, and Melkersson-Rosenthal syndrome.
- Biopsy is usually not necessary, and diagnosis is based on appearance alone.
Microdontia
- Condition in which one or more teeth are smaller than normal.
- Usually more common in women.
- There are 2 types: generalized (>14 teeth affected) and focal (<14 teeth affected)
- Associated conditions include and are not limited to, pituitary dwarfism, Down syndrome, congenital heart disease, and endocrine disorders.
Macrodontia /Megdontia
- Condition in which one or more teeth are larger than normal, more common in men.
- Two forms: generalized and localized.
- Generalized is associated with gigantism, relative is due to smaller jaw.
- Localized is associated with facial hemi hypertrophy
Rhizomicri and Rhizomegaly
- Rhizomicri is when tooth roots are smaller than usual and commonly affect maxillary lateral incisors, maxillary third molars and maxillary and mandibular first premolars.
- Rhizomegaly (Radiculomegaly) is when the root of the tooth is larger than usual and most commonly affects maxillary and mandibular cuspids.
Complete/Total Anodontia and Partial Anodontia
- Complete: congenital absence of all teeth, extremely rare
- Partial: congenital absence of one or more teeth, usually occurring more commonly in the third molars, maxillary lateral incisors, or second premolars
Hypodontia and Oligodontia
- Hypodontia: congenital absence of one or more teeth (less than 6)
- Oligodontia: congenital absence of more than 6 teeth.
Hereditary Ectodermal Dysplasias
- Group of hereditary diseases affecting skin, hair, and teeth.
- Examples include: Ehlers-Danlos syndrome, Rieger's syndrome, Down syndrome, Coffin-Lowry syndrome, Crouzon syndrome, and focal dermal hypoplasia.
- These are also associated with hypodontia or other dental anomalies.
Supernumerary Teeth
- Associated with many conditions like Cleidocranial dysplasia, Gardner syndrome, Ehlers Danilo syndrome, Down's syndrome, cleft lip and palate, Crouzon, and Sturge Weber.
Gemination
- Incomplete formation of two teeth from a single tooth germ.
- Resulting in two crowns that are connected by a single root/root canal.
- Commonly affecting the deciduous mandibular incisors and the permanent maxillary incisors.
Fusion
- Union of two adjacent normally separated tooth germs.
- Forming an anomalous crown instead of the usual two separate teeth.
- Incisors are often the teeth affected.
Concrescence
- The roots of two or more adjacent teeth have fused together by cementum.
- This occurs after root formation of the involved teeth has been completed.
Dilaceration
- Abnormal bend or curve in the root or crown of the tooth caused by trauma (i.e., injury to the deciduous tooth), or idiopathic factors.
- Permanent maxillary incisors are most commonly affected.
- The curve can be located apically, mid-root, or at the cervical portion of the root.
Talon Cusp
- An anomalous projection that arises typically in permanent maxillary incisors, especially the laterals, and less commonly in mandibular incisors. It is a lingual extension of the cingulum that resembles an eagle's talon.
- Commonly associated with the Rubinstein-Taybi syndrome
Dens Invaginatus (Tooth-Within-a-Tooth).
- Developmental anomaly characterized by a deep invagination of the tooth's crown, sometimes also involving the root.
- The invagination often forms a cavity within the tooth that is lined by enamel.
Radicular Dens Invaginatus
- Rare condition arising from the proliferation of the Hertwig epithelial root sheath.
- The enamel extends along the root surface.
- Most commonly affecting permanent laterals and premolars.
- The invagination is prone to caries and can lead to periapical inflammation.
Dens Evaginatus
- An accessory cusp or globule of enamel projecting from the occlusal surface.
- Usually involves premolars, rarely molars, or cuspids
- Often bilaterally present, frequently associated with shovel-shaped incisors.
Shovel Shaped Incisors
- Variant of Dens Evaginatus.
- Prominent marginal ridges creating a hollowed lingual surface resembling a shovel.
- May be seen on any tooth.
Taurodontism
- Developmental anomaly of teeth characterized by an enlargement of the pulp chamber and a reduction in the root length.
- The overall shape resembles the molar teeth of cud-chewing animals, hence the name.
- It can be either unilateral or bilateral, affects permanent teeth more than primary, frequently linked to syndromes like Down syndrome and Klinefelter's syndrome).
Ectopia
- Remote position location of a tooth outside of its normal position in the dental arch.
- Often caused by displacement.
- Includes maxillary canines erupting into, nasal or maxillary sinuses, or mandibular third molars erupting through the skin of the cheek.
Natal Teeth / Neonatal Teeth
- Natal: Erupted deciduous teeth present at birth.
- Neonatal: Deciduous teeth erupting within the first 30 days of life.
Periodontal Diseases - Causes
- Endocrinal disturbances (Adreno-cortical syndrome, Hyperthyroidism)
- Premature loss of deciduous teeth causing premature eruption of permanent teeth
- Systemic factors (Rickets, Cleidocranial dysplasia, Cretinism)
- Local factors (Fibromatosis gingivae, cleft lip and palate, retained deciduous tooth)
- Idiopathic
Periodontal Diseases - Embedded Teeth / Submerged Teeth
- Embedded teeth: unerupted teeth due to a lack of eruptive forces.
- Submerged teeth: ankylosed deciduous teeth, where the occlusal table is below the level of the surrounding permanent teeth.
Ectopic Enamel
- Presence of enamel in unusual locations, often on the surface of the tooth, usually maxillary molars and less commonly the mandibular molars.
Chronic Inflammatory Changes of Denture-Bearing Mucosa
- The conditions can include pinpoint erythema (Type 1), diffused areas of erythema with edema (Type 2), or nodular hyperplastic areas (Type 3), according to Newton's classification.
- Histologically, this condition exhibits hyperplasia or atrophy of the epithelium, keratinized or non-keratinized surfaces, and leucocytes infiltrating the epithelium to form microabscesses.
Hyperplastic Candidiasis (Candidal Leukoplakia)
- Least common; characterized by thickened parakeratin with surface corrugations; white plaque that's often associated with a previous leukoplakic lesion. -Histologically shows thickened parakeratin, acanthotic epithelium, areas of "balloon cells" (abundant cytoplasm in the upper spinous cells), occasional nuclear beading; and in most cases heavy candidal infestation of the parakeratin layer, even though a normal inflammatory response to the fungus is usually absent.
Angular Cheilitis
- The condition is characterized by erythema, fissuring, and scaling in the corners of the mouth. Often these conditions keep the oral mucosa moist, which can cause a yeast infection.
- This condition is frequently a result of chronic lip or tongue licking or thumb sucking
Denture Stomatitis
- Characterized by varying degrees of redness / erythema and sometimes petechial hemorrhage localized to the denture-bearing areas of the maxilla.
Fungal Infections (Oral Pathology)
- Histoplasmosis: appears as a painful solitary ulceration, shows a diffuse infiltrate of macrophages, and collections of macrophages organized into granulomas with cytoplasmic microorganisms. Often multinucleated giant cells are present.
- Blastomycosis: relatively uncommon fungal disease with lesions that may be irregular, erythematous, or white intact, sometimes appearing ulcerated with irregular borders and pain. Histology shows large yeasts of Blastomyces dermatidis and a pronounced host inflammatory response. A definite presence of acute or granulomatous inflammation, surrounding numerous yeasts, is noted.
- Cryptococcosis: uncommon fungal disease; characterized by craterlike, nonhealing ulcers that are tender to palpation or friable papillary erythematous plaques. Histologically, a granulomatous response is evident with the yeast appearing as round to ovoid structures and are often surrounded by a clear capsule.
Viral Infections (Oral Pathology)
- Herpes Simplex (HSV) infection, especially HSV-1, frequently occurs on the vermilion border, lips. This can lead to oral and perioral herpes labials. The lesions are intraepithelial blisters showing acantholysis and nuclear clearing (ballooning degeneration) of infected epithelial cells. These acantholytic cells are called Tzanck cells and are usually characterized by nuclear enlargement.
- Varicella (chickenpox): The varicella-zoster virus (VZV, HHV-3). These lesions are often located on the oral mucosa, lips & palate, beginning as 3-4mm white, opaque vesicles and ruptures into 1-3mm ulcerations.
- Herpes zoster (shingles): reactivation of the VZV
- Infectious mononucleosis (mono, glandular fever, kissing disease): caused by the Epstein-Barr virus (EBV, HHV-4). Oral manifestations often include petechiae of the hard or soft palate, which can be transient, and possibly necrotizing ulcerative gingivitis (NUG).
- cytomegalovirus (CMV) infections. Oral lesions are characterized by the presence of multinucleated giant cells, which are known as "Owl eye" cells.
Histopathologic Features (Dentin Dysplasia)
- Type I (radicular): A portion of coronal dentin is normal, but apically there may be areas of tubular dentin accompanied by osteodentin and fused denticles.
- Type II (coronal): Deciduous teeth show amorphous atubular dentin in the radicular portion, while, the coronal dentin is relatively normal. Permanent teeth exhibit relatively normal coronal dentin but the pulp has multiple pulp stones or denticles.
Premalignant Lesions
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Leukoplakia: A whitish patch in the oral cavity not attributable to other causes; it may involve the hard or soft palate, gingivae, buccal mucosa. Microscopically, this condition shows hyperkeratosis and often an irregular epithelial stratification pattern. Dysplasia may occur.
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Leukoedema: A grayish white opalescent appearance often noted on the buccal mucosa; it histologically shows an increase in epithelial thickness and intracellular edema of the spinous cells and sometimes rete pegs.
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Erythroleukoplakia: velvety-red patch of the oral mucosa that's clinically or pathologically not related to any other disease. Histological features include atrophic, but sometimes hyperplastic, epithelium. Dysplasia may be prominent.
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Carcinoma-in-situ (CIS): Dysplastic changes are observed in the basal cells of the epithelium, often extending to the superficial layers. A notable feature is the intact basement membrane.
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Actinic cheilosis/ chilitis: It is a premalignant lesion occurring in sun-exposed skin, as a result of long-term exposure to the sun’s ultraviolet radiation. Microscopically it is characterized by variation in epithelial dysplasia.
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Stomatitis Nicotina (Snuff dipper lesion): Specific white lesion found on the hard and/or soft palate of individuals using smokeless chewing tobacco. Histologically this lesion is characterized by hyperorthokeratosis, and epithelial dysplasia.
Oral Submucous Fibrosis
- A premalignant condition characterized by a mucosal rigidity due to fibroblastic transformation of the juxtaepithelial connective tissue layer
- Histologically, the condition is characterized by atrophic epithelium without rete ridges, dense collagen bundles in the connective tissue, and often an infiltration of inflammatory cells.
Lichen Planus
- A chronic inflammatory disease that affects the skin or mucous membranes.
- This condition features a distinctive pattern with six "Ps" including, the lesions showing a slightly raised and irregular appearance, are usually polygonal, purplish or violet, appear pruritic, and are prone to forming papules or plaques.
- Histologically, this condition shows hyperkeratosis, and sometimes a Saw-tooth appearance of rete ridges along with liquefactive degeneration of the basal cell layer. There is an absence of epithelial dysplasia in the cases of lichen planus.
Lichenoid Reaction
- It's similar to lichen planus, but it's drug-induced or happens after discontinuation of the drug.
- Microscopically will demonstrate parakeratinized, atrophic epithelium with liquefaction of basal cells and a dense lymphocytic infiltrate.
Discoid Lupus Erythematosus
- A chronic inflammatory disease of the skin, often characterized by a reddish scaly or patchy rash on skin.
- Clinically, the buccal mucosa, tongue, and palate are commonly involved.
- Histologically, hyperorthokeratosis or hyperparakeratosis and hydropic degeneration of the basal cell layer is seen.
Early Detection of Oral Cancer Workup
- Oral examination for visual detection
- Supravital staining assists in the detection of premalignant lesions. A cytological assessment (oral cytology) is conducted on scraped samples to examine cells and their abnormalities.
- Chemiluminescence light helps to assess cellular components for alterations.
- Autofluorescence of tissues (tissue autofluorescence) assesses the chemical components for potential irregularities in their structure.
Histopathology of Dental Caries
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Classification: by anatomical location (pit and fissure, smooth surface, cervical, root), severity (incipient, rampant, arrested), and chronology (infancy, adolescent, recurrent).
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Histopathological features: These conditions show a loss of the interrod substance, mucopolysaccharide, and transverse striations of enamel. There is an accentuation of incremental lines of Retzius.
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Zones of Enamel Caries: Translucent zone (submicroscopic pores); Dark zone (increased porosity due to demineralization); Body of the lesion (unaffected enamel layer between the dark and translucent zones); Surface zone (partially mineralized).
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Caries of Dentin: Microorganisms travel at variable speeds depending on various influencing factors. The initial change in dentin caries is presented as fatty degeneration of Tome's fibers accompanied by dentinal sclerosis; and just behind the zone of decalcification, a narrow zone of decalcification is seen before bacterial invasion of dentinal tubules. Coalescence and breakdown of adjacent dentinal tubules lead to the formation of liquefaction foci.
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Zones of Dentinal Caries: Observing from the pulpal side, the advancing edges of carious lesions reveal five zones: (1) fatty degeneration of Tome's fibers; (2) zone of dentin sclerosis; (3) zone of decalcification; (4) zone of bacterial invasion; and (5) zone of decomposed dentin.
Histological Features of Periodontal Diseases
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Incipient Gingivitis: characterized by a light inflammatory infiltrate composed of PMNs. It develops adjacent to the sulcular epithelium.
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(Plaque-induced) gingivitis is the most common form. The infiltrate will intensify along with the involvement of lymphocytes, plasma cells, and acute inflammatory cells. Areas of fibrosis, hyperemia, edema, or hemorrhage might also be present.
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Necrotizing Ulcerative Gingivitis (NUG): The surface epithelium is ulcerated and replaced by a thick fibrinous exudate containing numerous polymorphonuclear leukocytes and microorganisms. The connective tissue shows an intense hyperemia and infiltration with dense numbers of polymorphonuclear leukocytes.
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Plasma Cell Gingivitis: Pattern of gingival inflammation with rapid onset of sore mouths. Characterized histologically by psoriasiform hyperplasia and spongiosis of the surface; intense exocytosis, and frequent neutrophilic micro abscesses; underlying lamina propria contains many dilated vascular channels and numerous plasma cells comprise the dense chronic inflammatory infiltrate.
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Granulomatous Gingivitis: The affected areas appear as red or red-and-white macules, which involve the interdental papillae and marginal gingivae. The histopathologic features show focal collections of histiocytes, lymphocytes, and multinucleated giant cells, often forming well-formed granulomas within the lamina propria.
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Drug-Induced Gingival Enlargement: A reaction due to systemic medication, characterized by an abnormal growth of gingival tissues; the epithelium and connective tissue are not necessarily hyperplastic/hypertrophic.
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Hormonal: Inflammatory gingival enlargement during puberty in both genders. Often associated with pregnancy (gingivitis in pregnancy), this condition shows increased vascularity, fibroblast multiplication, edema, and leukocyte infiltration.
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Systemic: Gingival enlargement from systemic diseases such as leukemia. This shows immature leukocytes within the tissues. Granulomatous diseases like Crohn's disease, sarcoidosis, or Wegener's granulomatosis display fibrosis, collections of lymphocytes and plasma cells.
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Gingival Abscess: An acute, localized, painful lesion with an onset cavity surrounded by diffused infiltrates of polymorphonuclear leukocytes.
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Pericoronitis: the presence of an inflammatory lesion around impacted or partially erupted teeth in association with hyperplasia of the epithelium, intercellular edema and leukocyte infiltration. Underlying connective tissue will show increased vascularity and dense infiltration by lymphocytes.
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Nutritional Enlargement/Vitamin C Deficiency: Characterized by spongy, bleeding gums of scurvy, commonly a specific entity and may affect children more frequently. The surface epithelium is hyperplastic, shows intracellular edema, micro abscesses, and a dense infiltrate of chronic inflammatory cells within the connective tissue. Marked vascular dilatation is frequently observed.
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Regional Enteritis (Crohn's Disease): A slowly progressive disease; lesions are often found in the buccal mucosa that presents as diffuse swelling and indurations or ulcerations. Microscopically, it will include fibrosis and dense collections of lymphocytes and plasma cells. Also, lymphatic vessels appear to be dilated..
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Idiopathic Gingival Enlargement: The lesion arises before tooth eruption and often causes interference with eruption of teeth. Histologically, an apparent hyperplastic epithelium is noted, with elongation of rete ridges and mild hyperkeratosis. The underlying stroma is often entirely composed of dense bundles of mature fibrous tissue with few young fibroblasts.
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Periodontitis: Localized gingivitis, accompanied by inflammation of the gum tissues. As the apical border of the involved region approaches the alveolar crest and crestal fibers of the periodontal ligament, proliferation and potential tiny ulcerations are observed within the crevicular epithelium.
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Papillon-Lefevre syndrome: Hyperplasia of the crevicular epithelium accompanied by exocytosis that is seen within the underlying connective tissue. Increased vascularity and an inflammatory infiltrate, predominantly polymorphonuclear leukocytes, lymphocytes, histiocytes, and plasma cells, are present.
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Test your knowledge of various oral pathology topics with this quiz. Questions cover histological features of conditions such as leukoedema, carcinoma in situ, and erythroleukoplakia. Assess your understanding of significant histological findings and their clinical implications.