Lecture 6 & 8-9: Pulp Disease & Osteomyelitis 2022-2023 PDF

Year: 2022-2023 lecture 6: pulp disease (pulpitis) Term: I Introduction Pulpitis: Is the most common cause of dental pain and loss of teeth in younger people. Complication: Fol...

Year: 2022-2023 lecture 6: pulp disease (pulpitis) Term: I Introduction Pulpitis: Is the most common cause of dental pain and loss of teeth in younger people. Complication: Following of death of the pulp and spread of infection through the apical foramina into the periapical tissues, this in tum causes periapical periodontitis. Cause: 1. Dental caries (Bacterial): The main cause, after penetrating the dentine. 2. Traumatic exposure & Mechanical damage of the pulp. 3. Fracture of a crown or cusp 4. Thermal injury & Chemical irritation Type of Pulpitis ❖ First: Focal Reversible Pulpitis (Pulp hyperemia) Definition: Earliest forms of pulpitis where there is vascular dilatation of blood vessels of the pulp. Clinical Features 1. Tooth is sensitive to thermal changes. 2. Tooth responds to stimulation by the electric pulp tester at a lower level of current indicating a lower pain threshold (or a greater sensitivity) than that of adjacent normal teeth. 3. Teeth in which these conditions usually show deep carious lesions, large metallic restorations particularly without adequate insulation or restorations with defective margins. Histological features 1. Dilatations of blood vessels, 2. Edema fluid collects due to of damage of capillary walls leading to actual extra vacation of RBCs or diapedesis of WBCs. 3. Slowing of blood flow and hemoconcentration thrombosis. Treatment: It is a reversible condition, provided the irritant is removed before the pulp is severely damaged. Prognosis: Carious lesions should be excised and restored, or defective filling replaced as soon as it is discovered if the primary cause is not corrected, extensive pulpitis results with sub sequent (death of the pulp). ❖ Second: Acute pulpitis (Irreversible Pulpitis) Definition: It is a frequent immediate sequela of focal reversible pulpitis. It may occur as an acute exacerbation of a chronic inflammatory process. Type: Acute closed pulpitis & Acute open pulpitis Clinical features: 1. It usually occurs in a tooth with large carious lesion or restorations (recurrent caries). 2. Persistent sever pain is elicited by thermal changes particularly by ice or cold drinks. Increase sensitivity to both heat and cold, Severity of pain isa related to inflammatory response, 3. Inflammation abscess formation leading to more severe pain (lancinating). 4. Tooth reacts to the electric pulp vitality testers at a lower level of current than adjacent normal teeth indicating increase sensitivity to the pulp. 5. When necrosis occurs of the pulp tissue the sensitivity is lost. Histological Features: 1. Vascular dilatation & Edema fluid in connective tissue. Year: 2022-2023 lecture 6: pulp disease (pulpitis) Term: I 2. Payementing of polymorphonuclear leukocytes. 3. Migration of these leukocytes through the endothelial wall in large numbers. 4. Odontoblasts in this area are destroyed then it degenerates. 5. Small pulp abscess formation containing pus. The entire pulp undergoes liquefaction and necrosis. 6. In a few days acute inflammation spread to involve most of the pulp. 7. If the pulp is closed pressure is formed leading to rapid disintegration. Treatment and Prognosis 1. Once this degree of pulpitis occurs the damage is irreparable, 2. Acute pulpitis may become chronic pulpitis 3. Acute partial pulpitis needs pulpotomy. 4. Acute total pulpitis needs root canal filling. ❖ Third: Chronic Pulpitis Definition: It can arise from a previous acute pulpitis or occurs as the chronic type from the onset. The signs and symptoms: Are milder than those of acute form of the disease. Clinical features 1. Pain is not a prominent feature (a mild. dull ache) it is intermittent than continuous. 2. The reaction to thermal changes is reduced the threshold for stimulation by the electric pulp vitality tester is increased. Histological Features: 1. The pulp tissue is infiltrated by varying numbers of mononuclear cells, chiefly Lymphocytes and plasma cells. 2. Capillaries are usually prominent. & Pulp abscess formation 3. Fibroblastic activity is evident and collagen fibers are seen. 4. In case of wide-open exposure, the term ulcerative pulpitis is applied. Type: A. Chronic closed pulpitis B. Chronic open pulpitis (Chronic hyperplastic pulpitis or pulp polyp): It is a form of chronic pulp disease. It is uncommon and occurs as a chronic lesion from the start or as a chronic stage of a previously acute pulpitis. o Clinical Features: 1. There is proliferation of chronically inflamed dental pulp tissue. 2. It occurs almost exclusively in children and young adults and involves teeth with large open carious cavities. 3. It appears as a pinkish red globule of tissue protruding from the pulp chamber filling the entire cavity. 4. The teeth most involved are the deciduous molars and the first perm anent molars 5. Gum Polyp o Histological Features: 1. It is made basically of granulation tissue 2. The granulation tissue commonly becomes epithelized. o Treatment and Prognosis: The condition may be treated by extraction of the tooth or by pulp extirpation. ❖ Fourth: Gangrenous Necrosis of pulp Definition: Untreated pulpitis, either acute or chronic, result in necrosis of the pulp tissue, generally this is associated with bacterial Infection. ▪ NOTE: Saprophytic organism is associated in case of pulp gangrene. Year: 2022-2023 lecture 8 & 9: osteomyelitis Term: I Introduction Originates from: Greek words osteon (bone) & muelinos (marrow) & means infection of medullary portion of bone. Definition: It is an acute & chronic inflammatory process in the medullary spaces or cortical surfaces of bone that extends away from the initial site of involvement. Cells of bone: Resorption of bone matrix by osteoclasts. Deposition of new bone by osteoblasts Etiology: 1. Extension from dental infection (bacterial infection) (main cause. As periapical granuloma, abscess, & cyst. 2. Extension of infection from dry socket after tooth extraction. 3. Physical injury as fracture or surgical procedure. 4. Hematogenous spread 5. Acute Necrotizing Ulcerative Gingivitis (ANUG) where the Staphylococcus aureus & Streptococci. Factors predisposing to osteomyelitis A. Local factors (decreased vascularity/ decreased vitality of bone): Trauma, Radiation injury, Paget's disease., Osteoporosis, & Major vessel diseases B. Systemic factors (impaired host defense): Immune deficiency stales, Immunosuppression (Leukemia, AIDS.), Diabetes, Malnutrition, & Extremes of age. C. Virulence of microorganisms. ↑ Virulence of microorganism → Acute. ↓Virulence of microorganism → Chronic. D. Patient resistance: ↑ Patient resistance → Chronic. ↓Patient resistance →Acute E. Anatomic location Mandible is more affected than maxilla. Because mandible is formed of thick trabeculae & cortical plates, limited blood supply while the maxilla is thin and has a generous blood supply with rich collateral circulation. F. Patients age: Old age > young age. Causative organisms: Staphylococcus aureus (main type), Streptococci, Anaerobic bacteria (bacteroid), Porphyromonas, & Prevotella. Pathogenesis: 1. Inflammatory process of entire bone including cortex & periosteum, not just confined to endosteum 2. Inflammatory condition beginning in medullary cavity & Haversian system & extending to involve periosteum of affected area 3. Local factors decrease the vitality of bone 4. Systemic conditions comprise the defense system of the host CLASSIFTCATION ❖ First: Suppurative osteomyelitis [Acute & chronic]  Acute suppurative osteomyelitis: Males > females. Signs and symptoms of acute inflammatory process: As sign of any inflammation 1. Fever (pyrexia) & Leukocytosis [↑ WBCs count]. 2. Pain: Painful lymphadenopathy, Severe pain and the affected part is tender, & Numbness of the lower lip occurs if 3. Inflammation spreads to the inferior dental nerve. If the masseter muscle is involved, it lead to trismus 4. Intraoral: Soft tissue swelling as gums & the adjoining teeth become tender and loose. Year: 2022-2023 lecture 8 & 9: osteomyelitis Term: I Pathogenesis: 1. Acute inflammation of marrow: Micro-organisms enter the bone & proliferate giving rise to acute inflammatory process. 2. Spread of exudate along the marrow spaces: 3. Thrombosis of vessels due to compression: The inflammation causes increased tension in the blood vessels situated in the bone. As a result, the blood vessels cannot expand. This will lead to compression and tendency to thrombosis. 4. Necrosis of bone: When the blood supply from the periosteum and the adjoining normal bone is cut off, the affected part gets necrosed. 5. Sequestrum: Is a fragment of necrotic bone that has separated from the adjacent vital bone.  Character: hard, rough, porous, light in weight, lighter in color than normal bone.  Complication: If the sequestrum is long standing and surrounded by new living bone this is called involucrum  Treatment: If small they may be exfoliated through oral mucosa, but if large it must be removed surgically. (Unless bone sequestrum is removed surgically, Pus will continue to discharge.) Histopathology: 1. Purulent exudate occupies the bone marrow (spaces for pus). 2. Bony trabeculae show reduced osteoblastic activity. 3. The bone marrow is infiltrated by acute inflammatory cells. 4. If an area of bone necrosis occurs [sequestrum] osteocytes are lost.  Chronic suppurative osteomyelitis: Causes: 1. Inadequate treatment of acute osteomyelitis 2. Pulpal infections & Periodontal diseases 3. Infected fractures & Extraction wounds 4. Infection in the medullary spaces spread and form granulation tissue Complication: 1. Granulation tissue forms dense scar to wall of the infected area 2. Encircled dead space acts as a reservoir for bacteria & antibiotics have great difficulty reaching the site Clinical feature: 1. Symptoms are milder (swelling & pain 2. Formation of fistula & sequestrum 3. Fistula opens into gingiva & sometimes through the skin Histologic features: The inflammatory reaction in chronic osteomyelitis can vary from very mild to intense In mild cases: 1. Microscopic diagnosis can be difficult because of its similarity to fibro-osseous lesions. Only a few inflammatory cells are seen in the fibrous bone marrow. Lymphocytes and plasma cells). 2. Both osteoblastic and osteoclastic activity may be seen along with irregular bony trabeculae. In advanced cases: 1. Necrotic bone (sequestrum) may be present with loss of both osteoblasts and osteocytes. 2. Reversal lines reflect the wave of deposition and resorption of bone. 3. Inflammatory cells are more numerous and osteoclastic activity is more prominent than in mild type. Year: 2022-2023 lecture 8 & 9: osteomyelitis Term: I Prognosis: 1. Small lesions Curettage, removal of necrotic bone and decortication are sufficient. 2. Extensive osteomyelitis: Decortication combined with transplantation of cancellous bone chips. 3. Persistent osteomyelitis: Resection of diseased bone followed by immediate reconstruction with an autologous graft is required. Weakened jawbones must be immobilized. Acute Chronic No change in for the first 2 weeks. ill-defined Radiolucent lesion mottled with areas of radiopacity giving Radiograph radiolucency rise to what has been described as moth-eaten. 1. Selective antibiotic. 2. Sequestrectomy 1. Antibiotics and drainage. 3. Surgical removal of sinus tract. 2. Sequestrectomy. (Removal of dead necrosed 4. Immobilization of the jaw if pathological fracture Treatment bone is a must for healing to occur & may need 5. Difficult cases need hyperbaric oxygen which: surgery). a. Stimulate vasculature proliferation & collagen synthesis. b. Osteogenesis: Long lasting of 100% O2 2h/day for weeks to reach elevated tissue oxygen level by the end of therapy. ❖ Second: Sclerosis (non-suppurative) osteomyelitis [chronic only]  Chronic focal sclerosing osteomyelitis/condensing osteitis: Localized area of sclerosis  Chronic diffuse sclerosing osteomyelitis: This is like the focal type except that it is more generalized throughout the jaws.  Chronic osteomyelitis with proliferative/ condensing periostitis. (Gare’s osteomyelitis): ❖ Third: Special type  Radiation osteomyelitis/Osteoradionecrosis (ORN): Is a serious complication of radiation therapy in cancer treatment where radiated bone becomes necrotic and exposed. ORN occurs most commonly in the mouth during the treatment of head and neck cancer and can arise over 5 years after radiation.  Chemical osteomyelitis (Bisphosphonate- induced osteonecrosis of the Jaws (BINJ): It is Exposed necrotic bone appearing in the jaws of patients treated by systemic IV or oral BPs, that persists for at least 8 weeks, in the absence of previous radiation and metastasis. BINJ is caused by: 1. Secondary infection of wound in a patient undergoing bisphosphonate therapy. 2. Dental or oral intervention (extraction, PDL disease, dental implant procedure, exostoses, ill-fitting denture). Mainly Bisphosphonates: They are a class of drugs that prevents loss of bone mass by inhibit osteoclasts. Used: 1. Osteoporosis, Osteogenesis imperfecta, & Pagets disease of the bone, 2. Metastatic tumours of the bone such as: Breast, Prostate, & Renal cancer 3. Multiple myeloma & Primary hyperparathyroidism. o Beneficial effects 1. Therapeutic protocol used to manage bone invading tumors and hypercalcemia of malignancy. 2. Marked reduction in: Pain, Number of pathological fractures as Osteolytic bone size. Year: 2022-2023 lecture 8 & 9: osteomyelitis Term: I o Side effects Oral: A. Stomach upsets and inflammation. B. Erosions of the esophagus (sometimes esophageal cancer). Intravenous (IV): Give rise to (BINJ) o Precautions: Should be postponed until after dental treatment and the uses of antibiotics.  Alveolar osteitis (Dry socket) It is localized inflammation of bone & unpredictable complication of tooth extraction (1-3%). Caused by: 1. Failure of blood clot to form: May be due to poor blood supply as in Paget's disease of bone and osteopetrosis. 2. Premature loss of clot: Excessive mouth rinsing. Or disintegration (fibrinolysis) of clot by proteolytic bacteria. Most frequent to occur following: 1. Molar extraction, particularly mandibular third molars. 3. Difficult extractions following radiotherapy. 2. Excessive use of vasoconstrictors in local anesthesia. 4. In tobacco users. Clinical features 1. Severe pain develops a few days after extraction. 2. Sockets often contain foul tasting and smelling food debris which can be washed away to reveal denuded bone. 3. Without treatment, healing is extremely slow. Year: 2022-2023 lecture 8 & 9: osteomyelitis Term: I Year: 2022-2023 lecture 8 & 9: osteomyelitis Term: I Focal sclerosing osteomyelitis Diffuse sclerosing osteomyelitis Gare’s osteomyelitis 1. Uncommon form of bone reaction to infection. Only when an infectious process is responsible for sclerosis Respond to 2. Low grade inflammatory stimulus. Which leads to of bone. proliferation of bone in focal areas of bone sclerosis at apex. 1. Pulpitis or pulpal necrosis (non-vital tooth). 1. Periapical abscess of lower molar [endosteum + periosteum] Etiology 2. Malocclusion (vital tooth). It considered as idiopathic 2. Occasionally. [periosteum only] sclerosis. No treatment of sclerosed bone. 3. Mechanical irritation of a denture [Periosteum only] Age Young adults before 20 Black females of middle age Young adults Clinical feature Site lower1st molar teeth Mandible Post part of the mandible. Pain discovered during routine radiographic examination Vague pain, may undergo acute exacerbation Presenting feature of the jaw. Swelling of the outer surface of the jaw, Other Residual lesion seen radiographically even after extraction Microscopic culture should be positive with normal overlying skin. 1. Affecting a large part of the jaw & ill defined. 1. Onion skin appearance. Radio- 1. Circumscribed radiopaque surrounding the apex. 2. Early, radiolucent zones may appear in association with 2. Lateral jaw radiographs may fail. graphically 2. The entire root outline is visible sclerotic masses 3. Viewed on an occlusal film. 3. Advanced, radiopaque with cotton wool appearance. 4. New bones are smooth & well calcified. 1. Cementoblastoma: No visible lamina dura or root (vital 1. Cultures should be + to make definite diagnosis D.D tooth) 2. Negative cultures be evaluated for Chronic tend 2. Idiopathic Periapical Osteosclerosis: vital tooth) periostitis, SAPHO syndrome 1. Dense irregular bony trabeculae & lined by numerous 1. Dense masses of bone trabeculae with little marrow. Same for Diffuse sclerosing Histologic osteoblasts. 2. The marrow is fibrotic and infiltrated by chronic cells. osteomyelitis but not Mosaic features: 2. Focal osteoclastic activity is present and their alteration The same for Diffuse sclerosing osteomyelitis appearance with osteoblastic activity results in the "Mosaic appearance". Treatment: 1. Removal of the cause. 2. Antibiotics 3. Then the mandible undergoes gradual remodeling without surgical interference. Year: 2022-2023 lecture 15 & 16 developmental disturbances of teeth, oral and para-oral structures Term: II Introduction The disturbance may be: 1. Hereditary (genetically transmitted). 2. Acquired (any condition occurring during the intrauterine period). Outcome of disturbance during stages of tooth development: 1. Initiation: leads to change in the number of teeth. 2. Morpho-differentiation: leads to change in shape and size of teeth. 3. Calcification: leads to change in the tooth structure. Teratogenic: Is any agent that can induce or increase the incidence of a congenital malformation. Examples: 1. Maternal nutritional imbalance. 4. High alcohol intake. 2. Infectious agents. 5. Extremes of temperature. 3. Metabolic diseases. Disorders of development of teeth and related tissues 1. Developmental disturbances in the number of teeth A. Anodontia/Total anodontia: Total failure of development of a complete dentition. Affect only on permanent dentition. B. Hypodontia (oligodontia/Partial anodontia): Failure of development of one or more teeth, it associated with: 1. Down syndrome: 2. Hypohidrotic ectodermal dysplasia: It is a systemic disease characterized by the loss of ectodermal structures: a. Hypodontia. c. Hypotrichosis (scanty hair). b. Anhidrosis (inability to sweat) d. Defective finger nails. 3. Hyperdontia (additional teeth): Additional teeth are relatively common. The additional teeth are in the form of: Supplemental teeth: Extra-teeth resemble morphologically a tooth of normal series. [upper lateral incisor, & premolars]. Supernumerary teeth: Extra-teeth differ morphologically from normal teeth, being conical or peg shaped.  Several terms are used to describe supernumerary teeth depending on their location: 1. Mesiodens: a mid-line supernumerary tooth in the maxillary anterior incisor region. 2. Distomolar: an accessory fourth molar. 3. Paramolar: a posterior supernumerary tooth situated lingually or buccally to a molar tooth. 4. Natal teeth: Are accessory teeth that present at or shortly after birth in newborns. 5. Neonatal teeth: are those arising within the first 30 days of life. 6. Dental transposition: When normal teeth erupt into an inappropriate position. 2. Developmental disturbances in the size of teeth A. Microdontia: The teeth are physically smaller than usual. It associated with Down syndrome especially dwarfs patients. B. Macrodontia: Teeth are physically larger than normal. It associated with Pituitary gigantism. 3. Developmental disturbances in the shape of teeth A. Simple conical teeth: An exaggerated cingulum of central or lateral incisor. B. Double teeth: Abnormally shaped tooth appears as two teeth joined together into one tooth. It may be due to: 1. Gemination: Incomplete division of a single tooth germ results of two incompletely separated teeth (bifid crown). 2. Fusion: Complete division of a single tooth germ results of two incompletely separated teeth one normal & one supernumerary tooth. Fusion must involve at least dentin and cementum. 3. Concrescence: It is the union of two teeth by cementum. It is caused by trauma. Year: 2022-2023 lecture 15 & 16 developmental disturbances of teeth, oral and para-oral structures Term: II C. Accessory cusps: The cuspal morphology of teeth exhibits minor variation among different populations. 1. Cusp of Carabelli: Cusp located on the palatal surface of the mesiolingual cusp of a maxillary molar. 2. Talon cusp (dense evaginatus of anterior teeth): Cusp located on the lingual aspect (cingulum) of anterior teeth. It resembles an eagle's talon. 3. Dens evagination (central tubercle): Cusp on the occlusal surface between the buccal and lingual cusps of premolars D. Dens invagination (Dens in dente): Part of the enamel organ invaginates into the dental papilla during development E. Enamel pearl (enameloma): Small nodule of enamel formed on the root surface.  Causes: This may result from cells of Hertwig's sheath that have differentiated into ameloblasts. F. Taurodontism (Bull like tooth): Enlargement of the body and pulp chamber of a multirooted tooth  Causes: Failure of Hertwig's epithelial root sheath to invaginate at a proper horizontal direction.  It classified according to the degree of apical displacement of the pulpal floor into: 1. Mild (hypo-taurodontism). 2. Moderate (mesio-taurodontism). 3. Severe (hyper-taurodontism). G. Dilaceration: It is an abnormal angulation in the root. It is caused by trauma to a deciduous tooth. H. Accessory/ Supernumerary roots: Any tooth may develop accessory roots. 4. Developmental disturbances in the structure of teeth A. Disorders of dentin development: 1. Dentinogenesis imperfecta: Affected teeth show: a. The crown shows amber coloration (blue brown) or is opalescent. b. Bulbous crown and short roots. c. The enamel chips away. Soft dentine will be exposed, rapidly wear off & worn down to the gum level. [Adolescence] d. Absence of predentin. e. The tubules are large in diameter and less numerous. f. The pulp chamber is obliterated by the continuous formation of imperfect dentin. 2. Shell teeth: Variant of dentinogenesis imperfecta. Result of a very large pulp chamber surrounded by a thin shell of dentin. 3. Dentinal dysplasia (rootless teeth): Teeth with very short roots. The teeth are typically lost early in life because weak support given by the short roots. 4. Regional odontodysplasia (ghost teeth): Deficiencies of all the hard tissues of the teeth (enamel, dentin & cementum)  Radiographically: The hard dental tissues are thin, poorly mineralized & the teeth have been described as ghost teeth B. Disorders of enamel development: It is divided into: Hereditary anomalies Acquired (environmental) factors Dentitions Affect both Affect one dentition Structure Affect either enamel or dentin Affect both enamel and dentin Produce Diffuse or vertically oriented defects Horizontal oriented defects Year: 2022-2023 lecture 15 & 16 developmental disturbances of teeth, oral and para-oral structures Term: II ❖ First: Hereditary alteration in enamel structure: amelogenesis imperfect Normal enamel is formed in 3 stages: 1. Formative stage: Organic matrix is deposited by the ameloblasts. It is responsible for the normal thickness of enamel. 2. Calcification (mineralization) stage: Enamel matrix is mineralized by the formation of crystals and removal of most original proteins. 3. Maturation stage: Enamel undergoes final maturation as the crystals enlarge and mature. Types of amelogenesis imperfecta A. Hypoplastic amelogenesis imperfecta (Formative stage): Organic matrix formation is defective: thickness of enamel is less than normal (quantitative defect)  Clinical feature: 1. Calcification and maturation are normal, with normal hardness and translucency. 2. Irregular enamel is pitted or thin B. Hypocalcified amelogenesis imperfecta. (Calcification stage): Enamel matrix is formed in normal quantity.  Failure in normal calcification: As a result, the enamel will abrades easily exposing the dentin which wear & weak. C. Hypomaturation amelogenesis imperfecta (Maturation stage): Normal enamel matrix is laid down and begins to mineralize. The defect is in the maturation of the crystals of the enamel which give mottled shape. ❖ Second: Acquired (environmental) alterations in enamel structure. A. Local factors: 1. Trauma 2. Infection (turner teeth): Defects of permanent teeth whose development has been disturbed due to periapical inflammation of the overlying deciduous tooth. The incisal third is commonly affected, with horizontal defects. 3. Irradiation and cytotoxic chemotherapy. B. Systemic factors: Fluorosis (Mottled enamel), Tetracycline pigmentation, & A Congenital syphilis. Classification of developmental disturbances of oral and para-oral structures 1. Developmental disturbances of the jaws 1. Agnathia: Complete or partial absence of upper or lower jaws. Or more commonly a portion of the jaw such as one side of the mandible, the condyle, ramus or premaxilla. 2. Micrognathia: Is the presence of a small jaw, either maxilla or mandible. It could be: A. Relative: Due to posterior positioning of the mandible about the skull. B. True: When it associated with Pierre Robin syndrome.  Pierre Robin syndrome: Is characterized by the underdevelopment of the mandible with falling back of the tongue, obstructing the laryngeal inlet causing cyanosis and asphyxia. It is also associated with cleft palate and bifid tongue. C. Acquired: Due to trauma or infection that destroys the condylar growth. It gives bird face appearance. 3. Macrognathia: It Is an abnormally large jaw. It could be either true or relative. Several reasons: A. Pituitary gigantism: The entire skeleton increases in size. B. Acromegaly: Increase of the mandible size in hyperpituitarism in adults. C. Paget's disease of bone: increase in the maxillary size. 4. Facial hemihypertrophy: A very mild degree of imperceptible asymmetry in nearly all persons.  May occur involving: The entire half of the body, One or both limbs, & The face and head. Year: 2022-2023 lecture 15 & 16 developmental disturbances of teeth, oral and para-oral structures Term: II  Etiology: It is of unknown cause, but it could be related to vascular or neurogenic abnormalities.  Oral manifestations: A. The permanent teeth on the affected side are enlarged (crown and roots). B. They develop more rapidly and erupt earlier with premature shedding of deciduous teeth. C. The bone of the maxilla and the mandible is also enlarged. D. The tongue in the affected side is enlarged and shows a bizarre picture of enlarged lingual papillae. E. The buccal mucosa appears velvety and may seem to hang in soft, pendulous folds on the affected side. 5. Facial hemi-atrophy: It is the progressive atrophy of some or all tissues on one side of the face.  Oral manifestations: 1. Hemi-atrophy of the lips and tongue is reported. 2. Reduced growth of the jaws and the teeth on the affected side. 3. Retardation of teeth eruption. 6. Tori: Torus palatinus: It is a condition that occurs in the midline of the hard palate and results in a palatal bony hard mass.  Clinical features: Its either flat, spindle, lobulated or nodular.  Treatment: No treatment is needed except if it interferes with denture stability, where it is treated surgically. Torus mandibularis: A hereditary condition occurring on the lingual surface of the mandible above the mylohyoid line, opposite to the bicuspid teeth. It is usually bilateral. 7. Multiple exostoses: They are found on the buccal surface of the maxilla in the molar region. 2. Developmental disturbances of the lips and palate 1. Congenital lip pits and fistulas: Etiology 1. Notching of the lip at an early stage of development, 2. Failure of complete union of embryonic lip tissues (lateral sulci).  Clinical features A. It occurs on the vermilion border near the midline of either lip, but it is more common in the lower lip. B. Commissural pits appear as unilateral or bilateral pits at the corners of the mouth on the vermillion border. Fistula is an abnormal passage from a hollow organ to the surface. 2. Double lip (2 lip appearance): It is characterized by a fold of excess tissue on the inner mucosal aspect of the lip.  Clinical features: It mainly affect upper lip. The condition is not seen when the lips are in rest. Only during smile. 3. Cleft lip and cleft palate: Cleft lip is more common in boys while cleft palate is more common in girls.  Forms: 1. Unilateral incomplete (not reach to nose) cleft 2. Unilateral complete (reach to nose) cleft 3. Bilateral complete (reach to nose) cleft  It wide variations in the degree of severity and the tissue involvement: A. Bifid uvula which is the mildest form of cleft. B. Cleft of the soft palate only. C. Cleft of both soft and hard palates. D. Cleft of the hard palate that extends anteriorly through the alveolar ridge & lip producing complete cleft in the lip, ridge, and palate.  Dental changes: 1. Congenitally missing teeth or it may divide giving rise to supernumerary. 2. Enamel hypoplasia, microdontia, macrodontia and fused teeth are seen. Year: 2022-2023 lecture 15 & 16 developmental disturbances of teeth, oral and para-oral structures Term: II  Complications A. Esthetic problems. C. Regurgitation of food and liquid B. Speech has a hyper nasal quality. D. Ear problems: otitis media and Eustachian tube dysfunction. 3. Developmental disturbances of the oral mucosa 1. Leukodema. 2. Fordyce's granules/disease: Heterotopic collections of sebaceous glands intraorally.  Clinical features: 1. They appear after puberty as small yellow Spots. 2. They are located bilaterally in a symmetrical pattern on the cheek mucosa. 4. Developmental disturbances of the tongue 1. Aglossia: A congenital absence of the tongue 2. Microglossia: Congenital defect where the tongue is markedly small. 3. Macroglossia: It is an abnormally enlarged tongue. It may either: A. Congenital macroglossia: B. Secondary macroglossia: it occurs as a result of: Tongue tumors or Acromegaly.  Clinical features 1. The tongue may fill the entire mouth or even protrude from it. 2. The strong muscles of the tongue press on the teeth leading to malocclusion, 4. Ankyloglossia (tongue tie): It may either be complete or partial. A. Complete ankyloglossia: is due to fusion of the tongue with the floor of the mouth. B. Partial ankyloglossia: is more frequent (tongue tie). It is due to either: 1. Short lingual frenum. 2. Or the lingual frenum is attached near the tip of the tongue leading to restricted movement and difficulty of speech.  Clinical hint: A rare condition is hyper mobility of the tongue due to an abnormal long frenum. 5. Cleft/bifid tongue: Complete or partial cleft or fissure is present on the tip of the tongue extending backward. 6. Fissured tongue (scrotal tongue): Grooves on the dorsal tongue surface radiating from a midline central groove.  Causes: Chronic trauma and vitamin deficiency are considered as etiologic factors.  Symptoms: It is painless except when food debris collects, leading to irritation. 7. Median rhomboid glossitis: Recently, it was suggested that it is due to chronic fungal infection especially with Candida albicans.  Clinical features It appears in adults as an ovoid or rhomboid shaped reddish patch lacking filiform papillae. 8. Benign migratory glossitis (geographic tongue): Multiple circular or oval red areas of desquamation of the filiform papillae in the anterior two third of the tongue.  Clinical feature: Each area appears as a smooth red denuded area with slightly elevated yellowish serpentine borders with irregular margins. 9. Hairy tongue: It is hypertrophy of the filiform papillae of the tongue with lack of normal desquamation.  Etiology Although it is of unknown etiology, but it can be due to: 1. Fungal infection. 2. Systemic disturbance: anemia, gastric upset. Year: 2022-2023 lecture 15 & 16 developmental disturbances of teeth, oral and para-oral structures Term: II 3. Radiotherapy for head and neck tumors. 4. Certain drugs: sodium perborate, penicillin, hydrogen peroxide mouth wash. 5. Change in the local oral environment, whether in the saliva or the microbial flora. 10. Lingual varices: Varices are dilated, tortuous veins that are poorly supported by the surrounding tissue.  Clinical feature: It appears as red or purple vessels on the ventral surface and the lateral borders of the tongue as well as the floor of the mouth. 11. Lingual thyroid: The development of the thyroid gland occurs from the floor of the pharynx.  Histological features: It appears like normal thyroid tissue or embryonic thyroid tissue. Year: 2022-2023 lecture 10, 11, 12, 13, &14 cyst Term: I Introduction Cyst: Is an epithelial-lined pathologic cavity occurring in hard or soft tissues & contain a fluid or a semi-fluid material. ❖ First: Odontogenic cyst: Definition: Epithelial lining is derived from epithelial residues of the tooth forming organ. Origin: Which is/are Gives rise to' 1. Odontogenic keratocyte Epithelial rests of Dental lamina rests 2. Lateral periodontal cyst Serre’s 3. Gingival cysts (newborn & adult) 1. Dentigerous cyst (follicular) Reduced enamel Derived from the enamel organ covering the fully formed 2 Eruption cyst epithelium crown of unerupted tooth. 3. Inflammatory paradental cyst Epithelial rests of Formed by fragmentation of epithelial root sheath of Hartwig Radicular cyst Malassez  Inflammatory: A. Radicular (Periapical cyst): The most common cyst in oral cavity by 65%  Origin: Epithelial residues in the periodontal membrane (epithelial rests of Malassez) because of inflammation following the death of the pulp (non-vital tooth).  Clinically: 1. Pain: History of previous pain (pulp necrosis) 2. Site: Maxilla > Mandible In the maxilla: Anterior teeth are more affected especially upper 2 & the palatal root of 1st premolar & molar. In the mandible: Common site is post to the canine area 3. Age: Any age (rare in deciduous teeth) 4. Result: They enlarge & may cause expansion of the alveolar bone. It causes buccal or lingual expansion.  Causes 1. Mainly dental caries. 2. Pulp death from trauma & irritants. Restorative materials are more likely in the anterior teeth.  Pathogenesis: 1. Bacterial infection extends from inflamed pulp tissue, through apical foramen to reach periapical tissue. 2. Periapical granuloma is formed at the apex of the non-vital tooth. 3. Due to any inflammatory stimulus, the epithelial rests of Malassez normally found in the periodontal ligament will penetrate and proliferate in the pre-existing granuloma. They proliferate in the form of sheets, strands and arcades.  Mechanism of cyst formation 1. Proliferating epithelium within a periapical granuloma reaches a critical size: The central epithelial cells are away from nourishment as ep is avascular. As a result, they will degenerate & die and microcyst is formed & continues to expand. 2. Proliferating ep within a periapical granuloma is in the form of arcades: They trap cores of granulation tissue causing them to necrose (liquefactive necrosis). As a result, microcysts are formed, continue to expand & coalesce together 3. Epithelization of an abscess cavity.  Radiographic: Well defined round or oval RL area around the apex & surrounded by a RO continuous of lamina dura Year: 2022-2023 lecture 10, 11, 12, 13, &14 cyst Term: I  Cyst expansion & bone resorption: In the fibrous capsule of a cyst there are: 1. Inflammatory cell infiltrate (lymphocyte + plasma cell): Produce cytokines e.g., Interleukin 1, which stimulate… 2. Fibroblasts to release: Bone resorbing factor as Prostaglandins, & Collagenase (Stimulate osteoclastic activity)  Cyst expansion → Osmosis 1. Due to the large number of osmotically active molecules in the cystic fluid, the contents are hypertonic 2. Therefore, the cyst wall acts as a semipermeable membrane, 3. This results in the movement of fluid from the tissues into the lumen, increasing the hydrostatic pressure within the cyst causing it to expand in an unicentric ballooning pattern.  Cyst contents: 1. Vary from watery, straw colored fluid to semi-solid brownish material of paste-like consistency. 2. Breakdown products of degenerating epithelial, inflammatory cells, and connective tissue components. 3. Serum proteins: produced by the plasma cells due to inflammation (immunoglobulins) 4. Water, electrolytes, & Cholesterol crystals  Histopathology: Are lined by non-keratinized stratified squamous epithelium associated with chronic inflammatory cells in the connective tissue. Shape Fibrous capsule Newly formed cysts: Richly vascular & diffusely infiltrated by chronic Irregular & varies in thickness (immature cyst wall). inflammatory cells In established cysts tends to be more fibrous & less vascular with More regular & uniform in thickness (mature cyst wall) less inflammatory cells  Microscopic variations in the cyst wall: 1. Pseudostratified ciliated columnar epithelium (in case of maxillary teeth), from the maxillary sinus. 2. Dystrophic calcifications. 3. Uncommon keratinized lining. 4. Rushton bodies within the lining epithelium: Slightly curved bodies, amorphous in structure, eosinophilic in reaction, brittle in nature. It originates from Hematogenous: From thrombus formation inside small capillaries with disintegration of RBCS. Odontogenic in origin: Keratin or enamel cuticle. 5. Hyaline bodies: Appear as small, circumscribed pools of eosinophilic material that exhibit corrugated periphery of condensed collagen. 6. Russel bodies from degenerated plasma cells. 7. Cholesterol clefts with the associated foreign body giant cells (local tissue damage is the cause of its accumulation). 8. Collection of lipid cells - foam cells (lipid laden macrophages). B. Residual Radicular Cyst: It is a radicular cyst which persists after the extraction of the causative tooth.  Complication: It is a common cause of swelling of edentulous jaw in older age. (ill-fitting denture) C. Lateral inflammatory periodontal cyst: It radicular cyst forms on the side of a non-vital tooth because of the opening of a lateral branch of the root canal.  Clinical hint: It must be distinguished from the lateral developmental periodontal cyst. Year: 2022-2023 lecture 10, 11, 12, 13, &14 cyst Term: I D. Paradental (buccal bifurcation cyst): It radicular cyst originates from the reduced enamel epithelium of partly erupted 3rd molar vital tooth involved by pericoronitis.  Pericoronitis (Inflammation): Stimulates the proliferation and cystic degeneration of reduced enamel epithelium covering the unerupted part of the crown. Treatment of inflammatory cysts 1. The affected dead tooth may be extracted, or root filled & preserved, 2. Enucleation of the cyst. 3. Marsupialization: Is done for exceptionally large cysts where fracture is a risk.  Developmental A. Dentigerous (Follicular cyst): Macroscopic features: Type Central type (commonest) Lateral type Circumferential type (Rare). Site The cyst surrounds the crown of The cyst projects laterally from the Band around the circumference of the CEJ an unerupted tooth. & Attached side of the tooth and does not without involving the occlusal surface so to the CEJ completely enclose the crown. that the tooth may erupt through the cyst  Histopathology: 1. The lining of dentigerous cyst typically a thin regular layer of non-keratinized stratified squamous or low cuboidal ep. 2. Mucous cells may be present due to metaplasia. 3. The lining is supported by fibrous connective tissue capsule free from inflammatory cells, unless there has been secondary infection. 4. Islands of inactive odontogenic epithelium may be seen in the CT wall  Management & Treatment: 1. If the tooth is in a favorable position & a space is available, it may occasionally be possible to mercurialize a dentigerous cyst to allow the tooth to erupt. 2. Extraction of the associated tooth & careful enucleation of the soft tissue component is a definitive therapy.  Differential diagnosis 1. Unicystic ameloblastoma. 2. An odontogenic keratocyst in relation to a tooth. 3. Ameloblastic fibroma (in posterior mandibular region or in maxilla in young age). 4. Adenomatoid odontogenic tumor (AOT). B. Eruption cyst: Histopathology: 1. The lining of the eruption cyst is similar to the dentigerous cyst. 2. The fibrous capsule shows inflammatory cells possibly as a result of trauma. 3. The epithelial lining is separated from the alveolar mucosa by a thin layer of fibrous tissue. 4. Cyst content: Blood in addition to yellowish protein fluid C. Odontogenic keratocyte: It is characterized by unusual anteroposterior growth pattern & a tendency to recur.  Cyst Content: Keratocyst contains thick greyish white cheesy material consisting of keratinous debris.  Histopathology: Keratocyst has a thin, folded cyst wall Year: 2022-2023 lecture 10, 11, 12, 13, &14 cyst Term: I 1. It is lined by a regular continuous layer of parake-ratinized stratified squamous epithelium 2. 5-10 layers in thickness 3. No rete pegs (unless inflamed) 4. The basal cell layer consists of palisaded columnar or cuboidal cells with prominent hyperchromatic nuclei ( increased mitotic index & DNA synthesis ). 5. Above the basal cell layer there are several layers of polyhedral squamous cells that mature to a parakeratotic surface (wavy or corrugated) 6. The epithelial lining is weakly attached to the thin fibrous wall. 7. Budding of the basal layer of the epithelium in the underlying connective tissue occurs. 8. Solid groups of epithelial cells resembling the dental lamina could be present.  Concerning the fibrous wall: Thin fibrous wall & free from inflammatory cell infiltration. Satelite cysts or daughter cysts (islands of epithelial cells with central keratinization) are found (origin is again from the dental lamina).  Complication: Possible causes for recurrence: 1- Thin epithelial lining difficult to be enucleated 2- Finger-like cyst extension in cancellous bone. 1. Satellite c may be left in the bone post-operation. 2. Rapid epithelium proliferation (increased mitotic indication) 3. Other dental lamina remnants may produce another keratocyst (pseudo recurrence). 4. Budding of epithelium into the CT.  Nevoid Basal cell carcinoma syndrome: [Gorlin Goltz syndrome]: This syndrome is an autosomal dominant disorder characterized by 1. Sexual anomalies: Hypogonadism in male & Ovarian tumors in females 2. Cutaneous anomalies: Basal cell carcinoma, Benign dermal cysts & tumors, Palmer pitting, & Plantar keratosis. 3. Dental & osseous anomalies: Multiple odontogenic keratocysts, Mild mandibular prognathism, Bifid ribs, Frontal bossing, & Vertebral anomalies 4. Ophthalmic anomalies: Hypertelorism with wide nasal bridge, & Congenital blinding 5. Neurologic anomalies: Mental retardation & Calcification of cerebral meninges (falx cerebri) due to abnormalities in the Ca & phosphorus metabolism D. Orth keratinized odontogenic cyst: Is a cyst that microscopically has a uniform Ortho-keratinized epithelial lining which less aggressive & less likely to recur than the para-keratinized odontogenic keratocyte.  Microscopical findings: 1. Characterized by stratified squamous epithelium with cuboidal or flattened basal cell layer (not palisaded) that matures to ortho-keratinized surface. 2. Granular cell layer is noted immediately below the ortho-keratinized surface. Year: 2022-2023 lecture 10, 11, 12, 13, &14 cyst Term: I Cyst Dentigerous Eruption Odontogenic keratocyte. Result of accumulation of fluid between the REE & the Is the soft tissue analogue of the dentigerous It is a distinctive developmental odontogenic jaw Definition crown (cervical attachment). cyst. cyst characterized by parakeratinized stratified squamous epithelium. Enamel organ of an unerupted tooth after the crown of This cyst develops because of separation of the Dental lamina rests (epithelial rests of Serres). From Origin the tooth had been completely formed dental follicle (REE) extension of the basal cells of the ep (less common) In the maxilla: 3rd molar & canine. In the mandible: 3rd In the gingiva overlying the unerupted tooth Mandible > Maxilla [2:1]. Post part of jaws Site: molar & premolar specifically the third molar ramus area. There are no symptoms until the swelling becomes It occurs as a smooth bluish painless swelling No or few symptoms are recognized unless Symptoms noticeable, & is no pain, unless there is inflammation inflamed. It occurs in the second to the fourth decade Clinical Picture Age & sex Male, Usually young adults children are usually affected although it may occur at any age In routine radiographic examination when looking for Discovered the cause of a missing tooth, or a retained deciduous tooth. It is associated with the crown of an unerupted vital Trauma leads to accumulation of blood which The odontogenic keratocyst grows in an Others tooth gives the cyst a purplish or a brown color: anteroposterior direction and can reach large size Eruption hematoma without causing facial asymmetry Well-defined unilocular or multilocular RL associated 1. A well defined unilocular or multilocular with the crown of an unerupted tooth. radiolucency with thin radiopaque margins. Radiographically: 2. The roots of the adjacent teeth may be displaced (usually not resorbed). Year: 2022-2023 lecture 10, 11, 12, 13, &14 cyst Term: I E. Gingival cyst: Newborn (alveolar cyst) "Bohn's Nodules" Type Gingival cyst of adults "Epstein's pearls" Origin Epithelial rest of Serres 1. Maxillary & mandibular alveolus Site Mandibular buccal gingiva (canine- premolar area). 2. Midline or at the junction of the hard & soft palate 1. Soft tissue counterpart of the lateral PDL cyst 2. Rare cyst occurring over 40y. Clinically They are small, multiple whitish papules 3. Painless dome-like swelling less than 1 cm in diameter, & bluish- grey in color. Their lining is formed of thin flattened epithelium 1. The epithelial lining is thin, flat stratified squamous with a poor keratotic surface (small keratin filled epithelium with focal plaques & clear cells. Histology cysts) 2. Long standing cyst may cause cupping of the alveolar bone Treatment Resolve spontaneously by 3 months of age. F. Lateral PDL cyst: It origin from dental lamina remnants (epithelial rests of Serres).  Microscopic Picture: 1. It is lined by non-keratinized epithelium consisting of a single or a double layer of cells, 2. Focal-plague-like epithelial thickenings are noted (whorled appearance sometimes) 3. Clear cells which are glycogen rich can be observed in the cyst lining. 4. No inflammatory cells are detected in the capsule.  Botryoid odontogenic cyst: It is a polycystic variant of the lateral periodontal cyst. o Radiology: This cyst has a potential for recurrence & more rapid growth (multilocular radiolucency). o Treatment: Enucleation with preservation of the tooth if healthy o Clinical hint: The term botryoid is due to its resemblance to a bunch of grapes (grape-like clusters ). G. Glandular odontogenic cyst (Sialo-odontogenic) it DD is low grade central mucoepidermoid Carcinoma.  Microscopical Picture: 1. It is lined by cuboidal to columnar epithelial cells & exhibits crypt like spaces & microcystic spaces often lined by mucous cells. 2. The cystic cavity is lined by squamous epithelium. 3. The superficial cells lining the cystic cavity are cuboidal to columnar & have an irregular or a papillary surface, & cilia may be present. 4. Pools of mucinous material are found within the epithelium & are lined by cuboidal or mucous secreting cells (like the lateral period cyst). 5. The interface between the epithelium & the fibrous CT wall is flat 6. No inflammatory cells are found in the stroma. Year: 2022-2023 lecture 10, 11, 12, 13, &14 cyst Term: I H. Calcifying odontogenic cyst (Garlin): It’s an odontogenic cyst due to its considerable diversity & variable clinical behavior. Include columnar ameloblast-like basal layer, epithelium cells that resemble the stellate reticulum & ghost cells in the cyst lining ,lumen or the CT  Histopathology: 1. Well defined cystic cavity lined by odontogenic epithelium (4 to 10 cells in thickness) & a fibrous CT capsule. 2. The basal cells of the odontogenic epithelium are ameloblast- like cells (cuboidal or columnar). 3. The overlying layer of loosely arranged epithelium is formed of stellate reticulum- like cells. 4. This cyst may be associated with other odontogenic tumor such as odontoma, AOT & ameloblastoma (20 % of cases)  Ghost cells characteristics 1. They are present within the epithelial component, the lumen or the CT capsule. 2. They are altered epithelial cells, characterized by loss of nuclei, with preservation of the cell membrane. 3. The ghost cells may undergo keratinization (normal or aberrant keratinization), and are eosinophilic cells. 4. The ghost c may undergo calcification(basophilic). 5. Dysplastic dentin or dentinoid may be present adjacent to the epithelium. This is due to the inductive effect of the odontogenic epithelium on the adjacent mesenchymal tissue Year: 2022-2023 lecture 10, 11, 12, 13, &14 cyst Term: I Cyst Lateral PDL cyst Glandular odontogenic cyst (Sialo-odontogenic) Calcifying odontogenic cyst (Garlin) It is a developmental cyst which occurs on the lateral Its rare developmental cyst that can show aggressive Definition aspect or between the roots of vital teeth. behavior. It arises in the anterior part of the jaws (especially 75% of the cases are intraosseous, anterior to the Site: Mandibular bicuspid area (most common site). the mandible). first molar tooth (both jaws are affected). Clinical Picture Symptoms Asymptomatic lesion detected on routine radiograph. Slowly growing but symptomless. Age Adults Usually below 40 y. In some cysts expansion of the mandible is observed 1. Small > less than 1 cm in diameter Others lead to Perforation of the cortical bone with 2. It may be a large & involve most of the jaw and it involvement of the overlying gingiva (gingival cyst). is associated with pain or paresthesia. 1. Well defined unilocular or multilocular radiolucency containing varying amount of Well defined radiolucency on the lateral surface of the radiopacities. Radiographically: tooth root, between the alveolar crest and the root Multilocular radiolucency (sometimes unilocular). 2. Associated with the crown of an unerupted apex It looks like a drop of tear. tooth. 3. Root resorption and displacement of adjacent teeth is common. Enucleation or curettage with high recurrence rate in Enucleation with good prognosis for the cystic Treatment 30% of cases because of its potentially aggressive form (86-98%) with few recurrence. nature. Year: 2022-2023 lecture 10, 11, 12, 13, &14 cyst Term: I ❖ Second: Nonodontogenic cysts (fissure cysts): Definition: Epithelial lining is derived from sources other than the tooth forming organ. Type: The origin of these cysts: Has been questioned as being Fissure cysts. Type:  Nasopalatine duct (incisive canal) cyst: It is a developmental cyst arising because of proliferation of the epithelial remnants of the pai - red nasopalatine ducts (lying within the incisive canal). Which connect oral & nasal cavities together  Cyst of the palatine papilla: It is the soft tissue variant of nasopalatine duct cyst  Nasolabial cyst: It is a rare cyst which arises in the soft tissue of the upper lip, lateral to the midline, just below the ala of the nose, over the canine region.  Globulomaxillary cyst: It is a very rare lesion occurring between the roots of the maxillary permanent lateral incisor & canine teeth. ▪ NOTE: It is accepted now that the majority are odontogenic in origin & represents either a developmental lateral periodontal cyst or even a radicular cyst.  Median palatine Cysts (rare): Fissural cysts resulting from entrapment of embryonal epithelium at the line of fusion between the lateral palatal shelves of the maxilla  Radiographic: Well-circumscribed radiolucent area opposite to the bicuspid & molar region  Microscopic features: Lined by stratified squamous epithelium, or pseudostratified squamous epithelium. Chronic inflammatory cells may be present in the cyst wall  Median mandibular Cysts (commonly): Are very likely to be odontogenic in origin as there is no evidence of fusion of the epithelial lined processes at this site. Therefore, entrapment of ep should not be possible  D.D: Glandular odontogenic cysts, periapical cysts, odontogenic keratocysts, or lateral PDL cysts at the mandible Year: 2022-2023 lecture 10, 11, 12, 13, &14 cyst Term: I Cyst Nasopalatine duct Nasolabial cyst Globulomaxillary cyst. Trauma or bacterial infection can stimulate epithelial proliferation. It has been suggested that this lesion represents cystic Causes change of remnants of the cord of the nasolacrimal duct. The midline of the anterior maxilla between & posterior to the Site: central incisor teeth Clinical Picture Asymptomatic swelling, sometimes with sinus formation. The chief clinical sign is a soft tissue swelling over the Symptoms canine region or mucobuccal fold. Age & sex Female, Fourth and fifth decades It presents an inverted pear- 1. Well defined round, ovoid or heart shape radiolucency in the shaped radiolucency. midline between or above upper 1. 2. The anterior nasal spine is usually centrally superimposed on Radiographically: the radiolucent defect giving the heart shape. 3. Small cyst should be distinguished from the incisive foramen (usually 6 to 7 mm). 1. Oral end of the canal: Lining by stratified squamous epithelium Microscopical 2. Nasal side of the canal: Lining by pseudostratified ciliated Picture columnar ep 3. The CT wall is often infiltrated by chr inflammatory cells In the connective tissue wall : Lining by pseudostratified columnar epithelium which is Histopathology Small arterioles: From the greater & lesser palatine arteries sometimes ciliated, often with goblet cells or stratified Nerve tissue: From the sphenopalatine nerve squamous epithelium DD Periapical granuloma, Radicular cystt Incisive fossa Enucleation if the size of the cyst is small or marsupialization if the Excision with care to prevent perforation & collapse of Treatment cyst is of a large size. the lesion. Year: 2022-2023 lecture 10, 11, 12, 13, &14 cyst Term: I ❖ Third: Non-epitheliated primary bone cysts (pseudo): Cyst Solitary bone Aneurysmal bone cyst Stafne's idiopathic bone defect Trauma to the mandible → central Hemorrhage inside the bone 1. History of trauma: Primary aneurysmal bone cyst → failure of organization of blood clot → blood clot 2. Primary lesion in bone: Initiate an arteriovenous The lesion is a developmental defect Causes degeneration → empty cavity (Hemorrhagic bone cyst) → malformation → significant alteration in the rather than a pathological lesion, and expansion of this cyst in the medullary bone till the cortical bone hemodynamic forces→ secondary lesion or an once diagnosed, needs no treatment is reached & then the expansion stops. aneurysmal bone cyst. Posterior part of the mandible. It can occur at any Between the mandibular canal and Site: Mandible > Maxilla, lies above the mandibular canal part of the skeleton especially the long bones the inferior border of the mandible. Discovered coincidentally on X-ray Clinical Picture Pain is often reported although many cases are Symptoms examination and is symptomless. It painless, & swelling (rapidly developing) diagnosed by sialography test Age & sex Males, Children & adolescents (2nd decade of life) (18y) Under 30 years of age On auscultation bruit is not heard, Non pulsatile, & Others 1cm or more & it involves the molar area or extends to the ramus. Crepitus sometimes 1. Well defined radiolucency of variable size, sometimes with Unilocular or multilocular radiolucency with Round or oval well demarcated Radiographically: sclerotic border, depending upon the duration of the lesion. ballooning of the cortex (subperiosteal blow out). defect between the premolar region 2. Scalloping or festooning extends between the roots of the teeth, The cortical bone may be destroyed. and the angle of the jaw. The cystic cavity lined by loose, vascular, thin CT, hemosiderin It consists of a cellular fibrous CT stroma containing: pigments & no epithelium lining (pseudocyst) or a totally empty 1. Many cavernous or sinusoidal blood-filled spaces space. lined by fibroblasts & macrophages (histiocytes), not Histopathology by endothelial cells. 2. Multinucleated giant cells 3. Extravasated RBC's & hemosiderin. 4. New osteoid and bone formation could be present Year: 2022-2023 lecture 10, 11, 12, 13, &14 cyst Term: I  Solitary bone (simple, traumatic, or hemorrhagic bone cyst or idiopathic): Formation of this cyst may be due to hemodynamic disturbances in the medullary bone.  Aneurysmal bone cyst: It is a solitary blood filled, pseudocyst occurring within the bone either as a primary lesion or a secondary complication on the top of some other bone lesions  Described: As resembling a blood-soaked sponge with large pores representing the cavernous spaces of the cyst.  Grows & expands: Due to its direct connection with the blood circulation.  Stafne's idiopathic bone defect/ Development lingual mandibular salivary gland depression, Static bone cyst (usually bilateral): Part of the submandibular gland or an ectopic salivary gland tissue may develop within or more commonly adjacent to the lingual surface of the body of the mandible in a deep, well- circumscribed depression.  Complications: a salivary gland neoplasm may rarely develop from the included salivary gland tissue ❖ Fourth: Soft tissue cysts: Teratoma: It is a developmental tumor made up of number of different types of tissue which are not native to the area in which the tumor Occurs. This tissue is derived from the three germ layers (ectoderm, mesoderm & endoderm).  Dermoid cyst: Histopathology 1. The cystic cavity is lined by orthokeratinized, stratified squamous epithelium with prominent granular cell layer. 2. The fibrous connective tissue wall contains skin appendages (sebaceous gland, sweat glands & hair follicles). 3. Abundant keratin is found in the cyst lumen.  Branchial (lymphoepithelial cyst): Normal lymphoid tissue in the oral cavity 1. Waldeyer's ring (Palatine tonsil, lingual tonsils, pharyngeal adenoids). 2. Floor of the mouth, Ventral surface of the tongue, & Soft palate 3. May develop from excretory ducts of sublingual glands or minor salivary glands  Histopathology 1. The cystic cavity is lined by stratified squamous epithelium or pseudostratified columnar epithelium. 2. The underlying C.T shows lymphoid aggregates usually demonstrating well-formed germinal centers. 3. The cyst may contain a thin watery fluid , a thick gelatinous mucoid material, or keratin.  Thyroglossal cyst: It is an uncommon developmental cyst of the neck.  Histopathology: Vary depending upon the location of the cyst. 1. -If the cyst is above the level of the hyoid bone → the lining epithelium is stratified squamous epithelium. 2. -If it is below the hyoid b, the lining is respiratory ciliated columnar epithelium. 3. -Thyroid tissue, lymphoid tissue and mucous glands may be found. Year: 2022-2023 lecture 10, 11, 12, 13, &14 cyst Term: I Cyst Dermoid cyst Branchial (lymphoepithelial cyst) Thyroglossal cyst Is a form of cystic teratoma derived from embryonic germinal It is an uncommon developmental Definition ep but may also contain structures of the other germ layers. cyst of the neck. 1. Arises anywhere along the 1. Old theory: remnants of epithelium of the branchial embryonic thyroglossal tract between arches. Enclavement of epithelial debris persisting in the midline during the foramen caecum of the tongue & Origin 2. Recent theory: entrapment of epithelium (probably closure of the mandibular & hyoid branchial arches. thyroid gland. of salivary gland origin) within cervical lymph nodes 2. It arises from remnants of this tract with subsequent cystic degeneration. that do not become obliterated. 1. Typical lesion: occurs above the geniohyoid muscle 1. As a movable swelling in the between it & the oral mucosa → bulge in floor of the mouth→ lateral aspect of the neck anterior to the midline of the neck in the region of elevates the tongue difficult mastication & speech. sternocleidomastoid muscle, at the angle of the the hyoid bone (common). Site: mandible, in the submandibular area, or in the 2. If the cyst arises in a position high in 2. Deeper dermoidc: occurs between the geniohyoid & mylohyoid muscles leading to bulge in the submental area preauricular area. the duct -→ tongue substance (double chin) (lingual thyroid) → dysphagia. Clinical Picture Symptoms It is a pale-yellow fluctuant swelling Asymptomatic, circumscribed, movable mass. They are slowly growing, a duration of weeks to many It occurs in young pts but can occur at Age & sex Young adults, while in other sites at birth years. Late childhood or young adulthood. any age. 1 From 2 cm- 8 cm -→ 12 cm. So it may reach a huge size. Moves with the movement of the 2. When keratin debris & sebum (secretion of sebaceous The oral counterpart is known as oral Others tongue & may retract upon glands) fill the cystic lumen → doughy consistency. lymphoepithelial cyst (floor of the mouth). swallowing (firm). 3. Epidermoid cyst: If the cyst contains only keratin Infection Sinus tracts are formed and can open intraorally or on the skin. Abscess formation with a draining sinus may occur. Drainage occurs through a sinus. Treatment Surgical removal of both cysts Surgical excision. Year: 2022-2023 lecture 10, 11, 12, 13, &14 cyst Term: I  Salivary gland cysts: Mucoceles are classified as Cyst Mucous extravasation cyst (pseudocyst & common) Mucous retention cyst (true cyst): Ranula Mucoceles of the floor of the mouth Definition (Frog's belly) 1. Trauma or injury to the minor salivary gland excretory duct → results in severance to the Duct → extravasation of mucous into the Results from obstruction of salivary flow Duct obstruction by a stone anywhere Causes surrounding connective tissue → induces secondary inflammatory (intraductal calculus or CT scar after injury) → in the ductal system reaction in the CT (macrophages & neutrophils flood in the area). So mucin does not escape. 2. Granulation tissue surrounds the mucin pool forming a pseudocyst. Lower lip is the most common site& Buccal mucosa, floor of the mouth lower lip (accessory salivary gland), tongue, Major salivary glands: submandibular Site: Clinical Picture & ventral surface of the tongue (Blandin-Nuhn). floor of the mouth, palate & cheek. gland> sublingual & rarely the parotid. Painless , bluish, submucosal swelling, about 1 cm in diameter ,vesicle- Symp, like if superficial. Deeper lesions color is like the norm al mucosa. Age Any age Over 50 years, 1. Well circumscribed cavity containing mucin surrounded by a thin wall 1. Cystic cavity is lined by duct epithelial cells. Like that of mucocele except that a of compressed granulation tissue (compressed fibroblasts), so it is a 2. Type of lining ranges from pseudostratified definite epithelial lining is sometimes pseudocyst. cells to double layer of cuboidal or present. So, it is considered as a true Histopathology 2. The wall is infiltrated by large neutrophils, macrophages, & Chrc. cell columnar cell retention cyst occurring as a partial 3. The surrounding salivary gland tissue shows ductal dilatation & acinar 3. Mucin is found inside the cavity. blockage phenomenon. degeneration. 4. The epithelium is surrounded by CT. Salivary neoplasms (upper lip), Vascular malformations, Lipoma, Gingival Salivary neoplasm (upper lip), Extravasation DD & eruption cysts. (the mucocele appears in the alveolar mucosa). mucocele, & Connective tissue neoplasms. Complete removal of the mucous retention cyst Excision of the entire sublingual gland Treatment It should be excised with the underlying gland to prevent recurrence & associated lobules of minor salivary glands. to prevent recurrence Year: 2022-2023 lecture 15, 16, 17, 18, 19, 20, 21, & 22 odontogenic tumors Term: I Introduction Origin: Odontogenic epithelial or mesenchymal elements or both. that are part of the tooth-forming apparatus Site: They are found in the mandible or maxilla and are rarely found on the gingiva. Causes: Etiology and pathogenesis are totally obscure. Microscopely: Odontogenic tumor resemble cells or tissue of origin (like any tumor). So they resemble soft tissue of enamel organ or dental pulp and may contain hard tissue elements such as enamel, dentin, cementum or a mixture. Classification of odontogenic tumors and allied lesions (WVHO 2003) modified (WHO 2017) ❖ First: Benign odontogenic tumors  Epithelial Odontogenic tumor: Benign neoplasms arising from the odontogenic apparatus are made of odontogenic epithelium (proliferate) with mature fibrous stroma (just support), without ectomesenchyme. A. Ameloblastoma: Locally invasive neoplasm consisting of proliferating odontogenic epithelium in a fibrous CT stroma.  Character: 1. Its frequency equals all odontogenic tumors combined but excluding ectopic. It accounts for 1% of all oral tumors. 2. Non inductive in that it fails to induce any formed calcified product such as enamel, dentin or other material. 3. All ameloblastoma tumor lining by ameloblast like cell and over lining by stellate reticulum like cell.  Origin 1. Enamel organ or one of its layers. 2. Dental lamina or its residues (epithelial rests of Serres). 3. Epithelial root sheath of Hertwig or its residues (epithelial rests of Malassez). 4. Epithelial lining of odontogenic cysts, especially dentigerous and odontogenic keratocysts. 5. Basal layer of oral epithelium.  It has different clinic-radiographic situations with different therapeutic considerations & prognosis: 1. Conventional ameloblastoma and its variants.  Clinical features 1. Age & Sex: Females adults In children it occurs as a unicystic tumor. 2. Site: Mandible is more affected than maxilla: Mandible: The molar-ascending ramus area >premolar area > while anterior mandible Maxilla: molar area is the commonest site, with no deformity (as the tumor grows into the sinus). 3. Clinical course: a. It is slowly growing, locally invasive, asymptomatic condition. b. It is located centrally (intraosseous) in both jaws forming hard swelling. c. No clinical sign in early stage. d. Later, there is gradually increasing facial deformity, due to bone expansion both buccally and lingually. e. Teeth in the area may become loose. f. Tumors that continue to enlarge may cause thinning of the cortical plates of bone: eggshell crackling. Egg shell crackling is heard on clinical examination. g. Perforation of the bone is a late feature.  Radiographic features: Ameloblastoma is an osteolytic tumor which could be: 1. Multilocular radiolucency: Soap bubble when loculations are large & Honey combed when loculations are small. Year: 2022-2023 lecture 15, 16, 17, 18, 19, 20, 21, & 22 odontogenic tumors Term: I 2. Unilocular radiolucency: resembling cystic lesion although the margins show irregular scalloping, 3. Expansion gf the cortical plates of bone buccally and lingually. 4. Roof resorption of adjacent teeth is common. 5. In maty cases an impacted tooth especially loser wisdom is associated with the radiolucent defect.  Histological features There are 2 main patterns, depending on the arrangement gf epithelium. In some tumors both pattens coexist with no difference in the clinical behavior between various types: Plexiform ameloblastoma: The epithelium is arranged in a network of anastomosing stands and irregular mases which the same cell layers like follicular ameloblastoma. The supporting stroma ends to be loosely arranged and vascular. 1. Cyst formation is uncommon due to stromal degeneration (rather than cystic changes in the ep) leading to micro- cysts which may coalesce to form a larger cyst. 2. The blood vessels persist and dilate instead gf disappearing Follicular ameloblastoma (common): Its made of follicles resembling the enamel organ in a mature fibrous CT stroma o Consist of 1. Peripheral single layer of tall columnar cells called ameloblast- like cells, with their nuclei are located at the opposite pole to the basement membrane (reversed polarity) 2. Central core arranged angular cells with long anastomosing processes called stellate reticulum-like cells, where changes can occur. o Variant of Follicular ameloblastoma 1. Acanthomatous ameloblastoma: It happens when the squamous metaplasia occurs in stellate reticulum-like cells, resulting in keratin formation.  Histologically: It may be confused with squamous cell carcinoma or squamous odontogenic tumor. 2. Granular ameloblastoma (in young patients): Groups of stellate reticula- like cells become granular cells with abundant cytoplasm filed with PAS positive eosinophilic granules. By EM these granules represent lysosomes.  Histologically: Granules caused by increased apoptotic cell death & phagocytosis by neighboring neoplastic cell 3. Desmoplastic ameloblastoma: It is recently recognized and contains small islands and cords of odontogenic ep with spindle shaped central cells, in a dense collagenized (desmoplasia) stroma. Upper anterior region  Histologically: Ameloblast- like cells are inconspicuous about the epithelial islands.  Radiographically: It resembles fibro osseous lesions due to the mixed radiolucent & radiopaque (I’ll defined). 4. Basaloid ameloblastoma: It is the least common variant, composed gf nests of uniform hyperchromatic basaloid cells with no stellate reticulum- like cells, the peripheral cells are cuboidal.  Histologically: It resembles basal cell carcinoma of the skin or adenoid cystic carcinoma.  DD 1. Odontogenic tumors: Odontogenic myxoma, & early calcifying epithelial odontogenic tumor 2. Odontogenic cysts: dentigerous cyst & odontogenic keratocytes. 3. Non odontogenic tumors: Central giant cell granuloma, early ossifying fibroma, & central hemangioma.  Treatment: Amelobastoma tends to infiltrate between intact cancellous bony trabeculae at the periphery of the tumor. 1. Treatment with curettage is associated with recurrence rate of 55-90%. 2. Resection at least 1em post the margins is required. It reduces rate of recurrence to 15%.  Year: 2022-2023 lecture 15, 16, 17, 18, 19, 20, 21, & 22 odontogenic tumors Term: I Metastasizing (malignant) 2. Uni-cystic ameloblastoma [10-15%]: Extraosseous/peripheral ameloblastoma [1%]: ameloblastoma [1%]: Origin 1. De novo (new) as a neoplasm. Basal cell layer of oral epithelium or Odontogenict Cause of naming malignant: Its 2. Ncoplastic transformation of a precxisting cyst epithelial rests beneath the oral mucosa, in gingiva. Benign but microscopic features of Age: Youger group Middle age. ameloblastoma show some Clinical features Lower posterior gingival and alveolar mucosa (soft metastatic deposits. Because: Site: Lower posterior reqion (unerupted wisdom) tissue) 1. Several local recurrences of the Symptoms Asymptomatic, & low recurrence rate. Painlles tamor, mast commonly to lungs and regional LN 1. Perpheral odontogenic fibroma (no reverse polarity 2. Routes of spread: Can occur presence of dentin and cementum- like tissues). throug implantaion of the tumor DD Dentigerous cyst & Early adenomatoid odontogenic tumor 2. Non- odontogenic fibroma. into lymphatic or blood vessels (by 3. Pyogenic granuloma. repeated surgical interventions) or by aspiration. Radiographic Like dentigerous cyst which Unilocular or multiluclar RL. 1. Luminal ameloblastoma: At the lumin surface of the cyst 1. Could be made of basaloid cells and resemble lining by eptithelial basal layer of ameloblast- like cells basel carcinoma of the skin. revers polarity and hyperbromatic nuclei, coverd with loose 2. It is made of plexiform or follicles pattrens They are the same as that of vacuolatrd layer of stellat vriculum-like cells. ocurying the lamina propria of the surface Histological ameloblastoma 2. Intraluminal ameloblastoma: Ameloblastoma project from epthelium. the cell lining into he lumen of the cyst (follicular/ ploxiforn). 3. The tumor is connected to the basal cell of the 3. Mural ameloblastoma: The fibrous wall of the cyst is surface epithelium in 50 % of cases. inflerated by folicular or plaxiform amelobstoma. Treatment Enucleation Surgical excision  Year: 2022-2023 lecture 15, 16, 17, 18, 19, 20, 21, & 22 odontogenic tumors Term: I B. Calcifying epithelial OT (Pindborg tumor, CEOT): Locally invasive neoplasm (less aggressive than ameloblastoma)  Histological features 1. Epithelium: It is formed of sheets and strands of large polygonal epithelial cells in a mature fibrous stroma. 2. Nuclei: Show considerable variation in size, shape, and number (pleomorphism, but not indicating malignancy). 3. Cytoplasm: Is abundant and eosinophilic, and the desmosomes (intercellular bridges) are prominent. 4. Amyloid like material: Is formed intraepithelial and is liberated when the cells breakdown and it may become calcified. Special stain: Congo red or thioflavin-T. 5. Liesegang rings calcification: Is the calcifications are concentric laminated clusters that may fuse into complex masses. They are responsible for the radiopacities seen. 6. Variations: a. Focal zones of clear cells could be present. This gives rise to the clear b. Less calcification is found in case of the peripheral type. C. Squamous OT (rare): Locally infiltrative neoplasm or hamartoma consists of islands of will differentiated squamous ep in a fibrous stroma. The islands occasionally show foci of central degeneration, cystic formation, or keratin formation.  Histological features 1. Epithelium: It consists of irregular islands of squamous ep in a mature fibrous CT stroma: 2. Cell/Nuclei: No polarized basal cells as in ameloblastoma. 3. Changes: Micro-cyst formation, individual cell keratinization and keratin pearls are found within the islands. 4. Variations: Laminated calcific deposits & globular eosinophilic structures (negative for amyloid) are found within ep. ▪ NOTE: Maxillary tumors are more aggressive than mandibular with more invasion due to spongy bone of the maxilla. D. Adenomatoid odontogenic tumor (AOT): It has no glandular element. But have duct like structure, with varying degrees of inductive change in the connective tissue.  Clinical features: Variation a. Follicular (Central): Associated with the crown of an unerupted tooth in 71 % of cases. b. Extra-follicular (Central): Between the roots of erupted permanent teeth. c. Peripherally (RARE): As a small sessile mass in the anterior upper gingiva like fibroma or epulis-like attached to the labial or palatal gingiva.  Radiographic features a. Follicular: Well-defined unilocular radiolucent area with faint discrete snowflakes radiopacities very often associated with an unerupted tooth. Like dentigerous cyst but the radiolucency extends apically past the CEJ b. Extra-follicular: As a radiolucent lesion between the roots of erupted permanent teeth (inter radicular). c. Peripheral: Has no radiographic picture  Histological features 1. Epithelium: It is made of sheets, strands and whorled masses of polyhedral spindle shaped epithelial cells. 2. The tumor may be solid or cystic and well encapsulated. 3. Convoluted bands and tubular structures with very little supporting stromal connective tissue are formed 4. Ectomesenchyme: Is not found in this purely epithelial odontogenic tumor. 5. Foci of calcifications: Small throughout the tumor represent abortive enamel formation. 6. Multiple ducts like: Made of a single layer of cuboidal or columnar epithelial cells and enclosing a central space containing homogeneous eosinophilic material are feature. The nuclei of the ducts are polarized away from lumen.  Year: 2022-2023 lecture 15, 16, 17, 18, 19, 20, 21, & 22 odontogenic tumors Term: I Pindborg tumor/ CEOT Squamous odontogenic tumor AOT Is an amyloid-like material that may become calcified, is