Introduction Of Oral Pathology PDF

 Introduction of oral pathology Dr. Doaa Adel Habba Assistant prof. of oral and maxillofacial surgery department faculty of dentistry Najran university Glossary : 1. Disease: a state in which there is a sufficient...

 Introduction of oral pathology Dr. Doaa Adel Habba Assistant prof. of oral and maxillofacial surgery department faculty of dentistry Najran university Glossary : 1. Disease: a state in which there is a sufficient deviation from normal state for signs or symptoms to be produced. 2. Pathology: a branch: of medical science that is focused on the study and diagnosis of disease. 3. Oral pathology: it is the science dealing with oral diseases and systemic diseases that have oral manifestations. 4. Histogenesis: the tissue of origin of a lesion (e.g., epithelium or connective tissue). 5. Pathogenesis: the process (mechanism) by which an etiologic agent produces a disease. 6. Etiology: study of disease causes; an agent that causes disease. 7. Idiopathic: unknown cause. 8. Odontoiatrogenic: caused by dentist's procedures. 9. Hereditary (genetic): any trait transmitted through genes from parents to children.  Terminologies used in oral pathology 10. Hamartoma: is a developmental condition in which there is normal tissue in normal site but in an excessive amount. 11. Choristomas: forms of heterotopia are closely related benign tumors. These tumors also contain normal tissues but are found in abnormal locations. 12. Neoplasm: an abnormal mass of tissue, the growth of which exceeds and is uncoordinated with that of the normal tissues and persists in the same excessive manner after cessation of stimuli which induced the changes.  Terminologies used in oral pathology 13. Symptoms: the patient's complains. 14. Signs: the apparent features of the patients that doctor see or feel during examination. 15. Paresthesia: abnormal sensation (prickling or tingling sensation). 16. Numbness: loss of sensation. Oral tumors  Tissue Swelling Solid mass or enlargement; Tumor (Cell proliferation) Torus Palatinus Irritation fibroma Developmental Reactive lesion malformation Neurilemmoma True neoplasm  Tissue Swelling could be: 1. Developmental malformation (e.g. hemangioma, tori, ….etc.). 2. Inflammation either acute or chronic (e.g. dento- alveolar abscess, osteomyelitis…..etc.). 3. Reactive lesions; hyperplasia (pyogenic granuloma, peripheral giant cell granuloma, traumatic neuroma…..etc.). 4. Neoplasms (benign or malignant). 1- Developmental malformation  1- Developmental malformation  Condition or disease caused by error in the process of development.  Occurring in intrauterine life may be continue after birth.  Appear usually at birth (congenital) or soon after birth  Some conditions grow with the individual growth and stop to grow when general body growth stop.  A- Hamartoma Developmental malformation characterized by proliferation of normal tissue in normal site but in an excessive amount and appears as a tumor-like mass. Can be confused clinically with neoplasm. Examples 1.Melanocytic nevi Pigmented nevi 2.Hemangioma & Lymphangioma  Vascular nevi 3.White sponge nevus  White keratotic nevi 4.Maxillary and mandibular tori  B- Choristoma =Heterotopia Developmental malformation characterized by abnormal proliferation of normal tissue but in abnormal site. Examples Bone in soft tissue of buccal mucosa or tongue (Osseous choristoma or “Osteoma mucosae”)  Tissue Swelling Solid mass or enlargement; Tumor (Cell proliferation) Torus Palatinus Irritation fibroma Hamartoma Reactive lesion Neurilemmoma True neoplasm  2- Hyperplasia (Reactive lesions)  2- Hyperplasia (Reactive lesions) It is also a excessive tissue growth Increase in the size of tissue or organ due to increase the number of cells. Certain Stimulus Body Tissues Excessive Tissue Growth (hyperplasia) Removal of the Initiating Stimulus Stop its growth Early lesions may Regress. Old lesions sometimes do not regress and may need surgical treatment.  Oral irritation Oral mucosa is subjected to various stimuli (insults) such as: 1. Mechanical  chronic friction “frictional keratosis”. 2. Thermal  smoking “smoker's keratosis”. 3. Chemical  topical use of aspirin “aspirin burn”.  Mechanical Irritants Chronic, mild mechanical irritants are: 1. Cheek biting 2. Sharp badly broken-down teeth 3. Sharp restoration 4. Ill-fitting denture 5. Ill-fitting clasp 6. Sharp orthodontic wire  Frictional hyperkeratosis Friction  protective hyperkeratotic white lesion.  non-keratinized epithelium  acanthosis and keratinization  keratinized epithelium additional keratin formation Frictional hyperkeratosis Frictional keratosis  Focal hyperkeratosis Focal hyperkeratosis related to tongue-thrusting habit  Cheek biting Frictional hyperkeratosis A white lesion with a roughened keratotic surface caused by a chronic mechanical irritation. It is reversible after elimination of trauma. It should not be mistaken for true leukoplakia.  Cheek biting Frictional hyperkeratosis Hyperkeratosis: White rough epithelial thickening of buccal mucosa. Frictional hyperkeratosis Focal hyperkeratosis caused by chronic rubbing of the lip against teeth. Linea alba Chemical trauma aspirin burn  Aspirin burn An irregularly shaped, whitish area on the mucosa caused by the topical application of acetylsalicylic acid.  Snuff dipper's pouch Hyperkeratosis Wrinkled and fissured leukoplakia lines a "pocket" into which spit tobacco is packed. Snuff dipper's pouch Hyperkeratosis 3- Neoplasm  3- Neoplasm Neoplasm Neo =new plasia= formation  An abnormal mass of tissue, the growth of which exceeds and is uncoordinated with that of the normal tissues and persists in the same excessive manner after cessation of stimuli which evoked the changes (Willis 1952).  3- Neoplasm A new mass of tissue, the growth of which: 1. Independent= spontaneous, autonomous 2. Capable of unlimited proliferation 3. Exceeds and uncoordinated with growth of normal tissues 4. Does not regress after removal of the possible initiating cause.  What is differences between neoplasia and hyperplasia? Neoplasia Hyperplasia Etiology Spontaneously without have definite etiologic factors definite cause or may be as: caused by: 1. Trauma 1. Chemical carcinogens. 2. Low grade irritation 2. Ionizing radiation 3. Oncogenic virus (e.g. EBV, HPV) Persistence Once growth start it persistsGrowth persists as long as etiologic factor persist Progression Do not regress on removal of Regress on removal of the the causative stimulus causative stimulus  Classification of Neoplasms A. According to histogenesis (tissue origin): 1.Epithelial origin. 2.Mesenchymal origin. B. According to behavior regarding its biologic effect on the host: 1.Benign 2.Malignant 3.Potentially malignant epithelial only A. According to tissue of origin 1- Epithelial tissue 1. Surface or lining epithelium (oral epithelium= stratified squamous epithelium) 2. Glandular epithelium (salivary glands) 3. Odontogenic epithelium 2- Connective tissue 1. Fibers-------------------fibroma or fibrosarcoma 2. Blood vessels ---------angioma or angiosarcoma 3. Muscle------------------leiomyoma or leiomyosarcoma 4. Nerve-------------------neuroma or neurosarcoma 5. Adipose tissue--------lipoma or liposarcoma 6. Cartilage---------------chondroma or chonrosarcoma 7. Bone--------------------osteoma or osteosarcoma 8. Odontogenic mesenchyme Squamous cell carcinoma Fibroma  Benign Malignant 1- Clinical and gross appearance: Growth Grow by expansion Grow by infiltration and invasion. Slow growth rate Rapid growth rate Lesions tend to stop after It continues to grow until the reaching a certain size in some patient's death. tumors General clinical 1. Painless 1.Painful features 2. Well defined mass 2.Ill defined mass 3. Smooth edges 3.Irregular infiltrating edges involving 4. Soft in consistency adjacent tissue 5. Not fixed to the surrounding 4.Hard tissues=mobile 5.Fixed , non mobile, attached to the 6. Generally smaller in size surrounding, underlying and overlying tissue. 6.Variable in size  Benign Malignant 1- Clinical and gross appearance: Ulceration Intact surface Frequent surface Ulceration is unusual ulceration. except when traumatized Hemorrhage Unusual except when Frequently hemorrhagic. traumatized Metastasis Never metastasize Frequently metastasize Recurrence Do not recur when often recur properly surgically excised  Benign Malignant II- Histologic features: Differentiation Well differentiated Range from well degree of resemblance of (Similar to normal tissue in shape differentiated to neoplastic cells both and function) undifferentiated histologically and functionally to tissue of origin. Capsule Most benign tumors are Not capsulated. (in connective tissue capsulated. neoplasms) Except tumors of the surface epithelium and few infiltrative benign tumors as ameloblastoma & myxoma). Epithelial dysplasia Normal epithelium  Clinical Diagnosis  Signs & symptoms Sign= The finding elicited by the examining doctor Symptoms= The complaint described by the patient himself (e.g., pain, duration of the condition)  General description for clinical features 1. Age ------ Congenital , children , adult, old age 2. Sex ------Male or female 3. Site ---- – Intraoral or extraoral – Central (intra-osseous, intra-bony) or soft tissue (extra-osseous, extra-bony) – Tongue, lip, buccal mucosa …..etc 4. Symptoms (pt.’s complaint) --------- 1. Time history (onset and duration). 2. Pain, paresthesia, numbness. 3. Character --------- slow, rapid , intermittent growth. 5. Signs (doctor observation) 1. Size ------ always written in cm 2. Shape ------------------- A. Flat surface lesion (macule, patch, plaques). B. Elevated surface lesions /exophytic (papules, verrucous, papillary, nodule). C. Depressed surface lesions/ endophytic (ulcers). 3. Surface texture------ smooth or rough (verrucous, papillary) 4. Consistency ---------- fluctuant, soft, firm, hard. 5. Color-------------------- white, red, brown or same color as surrounding 6. Border------------------well circumscribed or irregular, ill-defined. 7. Base -------------------- sessile , pedunculated. 8. Number ---------------- solitary (single), multiple.  3- Site I. Soft tissue A. Intra-oral B. Extra-oral 1. Vurruca vulgaris 2. Kerato acanthoma 3. Basal cell carcinoma  3- Site II. Central lesions (RL, RO or Mixed RL&RO) RL RO Containing fluid cyst Containing soft tissue Containing calcified tissue (bone or cementum) Mixed RL&RO  4- Symptoms Pain Sharp  acute inflammation, dento- alveolar abscess Dull  chronic inflammation, deeply located lesion Paresthesia = Abnormal sensation (prickling, tingling, burning sensation) Numbness = Loss of sensation Tender = Pain on digital pressure  4- Symptoms Duration (time to reach max. size) Days  acute inflammation = (acute abscess) Months  malignant neoplasms Years  benign neoplasm or reactive condition Character of growth Slow  benign neoplasm or reactive condition Rapid  malignant neoplasms  5- Signs 1-Shape A- flat surface B- depressed surface C- elevated surface lesions. lesions. lesions. 1. Macules 1.Ulcers 1.Papules 2. Patches 2.Erosions 2.Papillomatous 3.Fissure 3.Verrucus 3. Plaques 4.Nodule  A- Flat surface lesions Macule= Spot A well circumscribed Flat Discolored area. It may be brown, red, or white. Less than 1.0 cm. Example – Nevi – Café-au-lait macules – Freckles  A- Flat surface lesions Patch= Flat Discolored lesion Larger than 1.0 cm Same as a macule but larger. Example Leukoplakia  A- Flat surface lesions Plaque= Thick, slightly raised above the surface/ a thick patch/ an elevated, plateau-like area Discolored lesion Larger than 1.0 cm. Example Leukoplakia B- Depressed surface lesions ⁄ endophytic  B- Depressed surface lesions Ulcer= Loss of the surface epithelium and some of the underlying connective tissue. It often appears depressed or excavated. All ulcers are painful except malignant ulcer All ulcers heal within max. 2weeks except malignant ulcer Example: Traumatic ulcer, aphthus ulcer Malignant ulcer (non healing ulcer) Malignant ulcer  C- Elevated surface lesions; exophytic Papule= Raised above the surface of normal surrounding tissues. Circumscribed Firm, solid lesion Small, usually less than 0.5 cm Examples: – Melanocytic nevi (mole)  C- Elevated surface lesions; exophytic Papillary= A small, thick, solid, raised; finger like surface projection  Papillomatous a tumor exhibiting multiple small surface projections found in clusters Example: 1. Squamous cell papilloma  C- Elevated surface lesions; exophytic Verruca= A raised surface lesion with many small projections. Verrucous Growth: tumor exhibiting a rough, warty surface. Example Verruca vulgaris Verrucous carcinoma  C- Elevated surface lesions; exophytic Nodules = Submucosal masses Elevated Lesions (under the mucosa) Greater than 5 mm in diameter.  C- Elevated surface lesions; exophytic Submucosal Mass: nodule A lesion arising in the connective tissues under mucous membranes. Nodule = – Elevated – Circumscribed – Solid – Measures more than 0.5 cm. Example – Keratoacanthoma – Benign connective tissue neoplasms Fibroma & Neurofibroma  5- Signs 2-Surface texture Smooth Rough Verrucous nodule Papillomatous Irregular surface  5- Signs 3- Base Sessile Tumor attached to surface directly by broad base without a pedicle The base is the widest part (largest diameter) of the lesion Example – Verrucous lesions – Nodules  3-Base Pedunculated Tumor attached to the normal surface by pedicle or stalk (neck) The base is narrower than the widest part of the lesion Example: –Papillomatous lesion  Squamous cell papilloma –Polyp  Fibro epithelial polyp  4- Color White Lesions Red Lesions Brown lesions  White lesions Mask the normal vascularity of the underlying connective tissue. Example 1. Leukoplakia 2. Leukodema 3. Oral submucous fibrosis  White lesions Causes of white color 1.Hyperkeratosis Increased surface keratin production (leukoplakia). 2.Acanthosis Increased thickness (number) of spinous cell layer of epithelium  White lesions 3. Spongiousis Intracellular edema of spinous cell layer (e.g. Leukodema) 4. Increased fibrosis in underlying connective tissue (e.g., Oral submucous fibrosis)  Red lesions Red lesions are said to be “erythematous’’ Example 1. Erythroplakia 2. Hemangioma 3. Acute Inflammation 4. Hematoma  Red lesions Causes of red color 1.Increased number & Dilated of blood vessels  inflammation, hemangioma, malignancy. 2.Thin overlying epithelium (atrophy) 3.Hemorrhage under the surface (Petechiae, Ecchymoses)  Brown lesions Melanin pigments Example 1. Nevi 2. Melanoma 3. Melanotic neuroectodermal tumor of infancy 4. Multiple neurofibromatosis 5. Polystotic fibrous dysplasia 6. Peutz Jegher syndrome  6-Borders Well defined Irregular Benign tumors Malignant neoplasms  7- Number Solitary Multiple Single Verruca vulgaris All neoplasms Multiple neurofibromatosis Multiple myeloma Histopathology  Normal oral mucosa Oral mucosa is either keratinized (gingiva and hard palate) composed of four epithelial layer 1. Basal cell layer 2. Spinous cell layer 3. Granular cell layer 4. Surface keratin layer Non-keratinized composed of three epithelial layer 1. Stratum basal 2. Stratum intermedia 3. Stratum superficial  Basal cell layer Basal cell layer = stratum germinativum = stratum basale = one layer of columnar or cuboidal cells, interspersed with melanocytes.  Basal cell layer Basal cell are ploripotential that can differentiate to different types of cells: 1.Squamous cells and eventually keratin (if it is keratinized) 2.Skin adenexae – Sweat glands – Sebaceous glands – Hair follicle  Basal cell layer The basal areas are the sites of cell proliferation (mitosis) where there is a continuous movement of cells in the direction of the free surface. rete ridge= rete pege= are the Connective tissue downward projections of the papilla epithelium that interdigitate with the superficial connective tissue papilla. Rete pege  Spinous cell layer Spinous cell layer= Prickle cell layer= Malpigian layer= Stratum spinosum= stratum intermedia. Normally about 6 - 8 cell layer. Polyhydral in shape Cell are adherent to each other by a desmosomal junction. The cells mature toward the surface and eventually become flattened  Histopathology Hyperkeratosis (excessive thickening of the keratin layer) which may be either "hyperothokeratosis" or "hyperparakeratosis."  Orthokeratin Parakeratin Granular Present Absent cell layer Contain kerato- hyaline granules Keratin nuclei are lost in keratin layer. nuclei are retained in keratin layer layer.  Histopathology Acanthosis Hyperplasia of squamous epithelium characterized by an increase in the number of the spinous cell layer. Normal epithelial Epithelial Hyperplasia thickness Acanthosis and Hyperkeratinization  Epithelial Hyperplasia Acanthosis and Hyperkeratinization  Epithelial Hyperplasia Acanthosis and Hyperkeratinization Thank you Thanks