Odontogenic and Associate professor Elitsa Deliverska, PhD Department of Dental, Oral and Maxillofacial surgery, FDM, MU- Sofia

Introduction

 The most commonly found at the apices of non-vital teeth are the periapical and radicular . The treatment and prognosis may differ according to the .  To decide treatment options of periapical lesion, whether surgery or not, necessitate precise diagnosis of the lesion as being granuloma, true cyst, or pocket cyst within granuloma mass.

Periapical is usually due to spread of following death of the and accumulation of inflammatory cells at the apex of a nonvital tooth. There is no evidence that necrotic pulp tissue can elicit periapical inflammation in the absence of . Tissue response to pulpal inflammation/ caused by microorganism invasion from:  Caries  Trauma  Medical induced  Allergy In the beginning all intent to localize the infection within the confines of the root canal system, but the progression of inflammation can lead to Inflammation of PDL around apical portion of root. Cause: spread of infection following , trauma (occlusal), inadvertent endodontic procedures etc. Types: 1. Acute Apical Periodontitis- serous or purulent 2. Chronic Apical Periodontitis

Etiological factors Trauma Acute injury • Injury on tooth • Cavity preparation without water spray • Vigorous prolonged polishing • Root planning in PDL therapy • Restoration – improper insulation Chronic injury • , -abrasive food & • Abnormal Medication • Medicaments or materials applied to diffuses through dentinal tubules. Microorganisms Bacterial invasion by: • Dental caries • Fractured tooth where exposed pulp • Anachoretic infection Anachoresis: In traumatized necrotic teeth with ‘intact’ crowns, microorganisms can reach the pulp through: • Microcracks • Accessory canals • Exposed dentinal tubules • due to presence of bacteria in circulating blood stream In contrast to pulp, periradicular tissues have an: • Unlimited source of undifferentiated cells • Rich collateral blood supply • Lymph drainage system Reaction of the provides a separation between the irritants and the bone, thereby preventing . Depending on the: • severity of irritation • duration • host response Periradicular pathoses may range from slight inflammation to extensive tissue destruction.

The ultimate biological aim of endodontic treatment is either to prevent or cure apical periodontitis and to preserve the tooth. Nonspecific mediators of inflammation are:   Fibrinolytic peptides  Kinins  Lysosomal enzymes Specific mediators of inflammation are:  Antigen-presenting cells  Immunoglobulins  Mast cells  -like cells  T cells  B cells are rare  Plasma cells are absent in normal pulp Pathophysiology of periapical lesion  inflammatory lesions of dental origin which are the most common of all other periapical lesions, are differentiated by certain terminologies as “periapical lesions of endodontic origin” or “pulpoperiapical” lesions to indicate that the cause is infected or necrotic pulp.  Inflammation of periapical membrane around the apex of the tooth is usually due to spread of infection following death of the pulp. In most cases inflammation remains localized to the periapical region. Diagnosis of the combined endodontic and periodontal lesions is often multifaceted and exasperating. A growing periapical lesion with secondary involvement of the periodontal tissue may have the similar radiographic appearance as a chronic periodontal lesion which has reached to the apex. An endodontically treated tooth or a nonvital tooth associated with periodontal lesion can pose greater diagnostic problem as in such cases pulpal inflammation is frequently associated with inflammation of periodontal tissue. Thus, a careful history taking, visual examination, diagnostic tests involving both pulpal and periodontal testing and radiographic examination are needed to diagnose such lesions. NORMAL PERIAPICAL TISSUES  No  Not abnormally sensitive to palpation and percussion  Normal intact lamina dura  Normal periodontal ligament With progression, the infection spreads along the path of least resistance. The purulence may extend through the medullary spaces away from the apical area, resulting in osteomyelitis, or it may perforate the cortex and spread diffusely through the overlying soft tissue (as abcess). It can starts as serous inflammation and to progress to purulent one. CLASSIFICATION of acute purulent periapical periodontitis- spreads along the path of least resistance  Periodontal stage  Endosteal stage  Subperiosteal stage  Submucosal stage - key features:  Dull throbbing constant pain  Pain on biting or percussion- most severe in subperiosteal stage  Palpation – pain in subperiosteal and submucosal stage.  Facial asymmetry- in subperiosteal and submucosal stage.  Negative or delayed vitality test response  Not associated with apical radiolucency  Widening of PDL space could be detected

The tooth should be non-vital to simple tests- it does not respond to cold and hot or electric pulp testing (as the periapical inflammation is usually provoked by a dead and/or infected pulp) although, particularly with multirooted teeth, some vital response may still be elicited. There is often a large carious cavity or filling in the affected tooth, or it may be discoloured due to death of the pulp earlier. The patient may give a history of pain due to previous . Acute periapical periodontitis could be divided to serous and purolent.

Diagnosis: according to: anamnesis, clinical and paraclinical examination. Important about case history:  CHIEF COMPLAINT  HISTORY OF PRESENT ILLNESS  MEDICAL HISTORY  DENTAL HISTORY  DRUG HISTORY The patient complains of a pain and feeling that the tooth is elevated out of the socket. Intaoral examinnation- inspection, palpation, percussion Clinical features - PAIN, mobility of the tooth could be detected • Thermal changes do not induce pain. • Slight extrusion of tooth from socket. • Cause tenderness on mastication due to inflammatory edema collected in PDL. • Due to external pressure, forcing of edema fluid against already sensitized nerve endings results in severe pain. - PERCUSSION: can be checked by applying finger pressure on the tooth or tapping with tip end of handle of the mirror; if pain then periodontal ligament is inflamed. Lateral percussion is done to check for marginal periodontitis or periodontal pocket disease Apical / vertical percussion is done to check for apical periodontitis - PALPATION: simple test done with finger tips using light pressure to examine tissue consistency & pain response around the apex of the tooth RADIOGRAPHIC FEATURES: - Appear normal except for widening of PDL space Pulp sensitivity test In case of purulent periapical periodontitis, the tooth is nonvital. Extraoral examination- inspection, palpation (facial symmetry, lymph nodes)

 Elevated temperature and malaise may follow. The body responds to this insult by trying to isolate the abscess and/or establish drainage intraorally. If drainage is not effective, the abscess may spread into fascial planes or spaces of the head and neck. Differential diagnosis could be made with: pulpitis osteomyelitis of jaws, maxillary sinuitis, denticle, neuralgia, exacerbation of chronic periapical periodontitis. - If a periapical radiolucency is present and an acute inflammatory response is superimposed on this preexisting chronic lesion it is termed a phoenix abscess. Management If tooth is in hyper occlusion, relieve occlusion. follow up the case with Pulp sensitivity test for at least one year if the cause for serous acute periodontitis is trauma. If tooth is infected, initiate endodontic therapy or extraction (if the tooth is not prospective) Incision and drainage should be done in subperiosteal and submucosal stage Medication include pain killers/NAID and antibiotics (if needed in 3-rd or 4-th stage).

Fill in!

In contrast to pulp, periradicular tissues have an: • Unlimited source of undifferentiated cells • Rich collateral blood supply • Lymph drainage system Periapical bone destruction Resorption of the bone provides a separation between the irritants and the bone, thereby preventing osteomyelitis. Depending on the:  severity of irritation  duration  host response ACUTE VS CHRONIC APICAL PERIODONTITIS  Acute: rapid onset, spontaneous pain, tenderness of the tooth to pressure, pus formation, and eventual swelling of associated tissues  Chronic: gradual onset, little or no discomfort, and the intermittent discharge of pus through an associated sinus tract. - Acute- Immediately round the apex the lamina dura may appear slightly hazy (loss of the lamina dura) and the periodontal space may be slightly widened. - Chromic- when there is acute periapical abscess due to exacerbation of a chronic infection, the original lesion can be seen as an area of radiolucency at the apex. Periradicular pathoses may range from slight inflammation to extensive tissue destruction

Chronic periodontitis is a low-grade infection. It may follow an acute infection that has been inadequately drained and incompletely resolved. It can occure acute exacerbation of a pre- existing chronic periapical inflammatory lesion.  Periodontitis chronica granulomatosa diffusa cum/ sine fistula  Periododntitis chronica granulomatosa localisata: - Granuloma simplex - Granuloma epithelisatum - Granuloma cysticum  Periodontitis chronica fibrosa  Periodontitis chronica granulomatosa exacerbata Progression of disease: Caries, trauma, --- Pulp necrosis---- Apical bone inflammation---- Granuloma formation----- Stimulation, then proliferation of epithelial cell rests of Malassez----- Cystification If a chronic path of drainage is achieved, a typically becomes asymptomatic because of a lack of accumulation of purulent material within the alveolus. Occasionally, such are discovered during a routine oral examination after detection of a sinus tract/fistula formation. Sometimes, the associated nonvital tooth may be difficult to determine, and insertion of a gutta-percha point into the tract can aid in detection of the offending tooth during radiographic examination. If the drainage site becomes blocked, then signs and symptoms of the abscess frequently become evident in a short time. Those periodontitis associated with a patient fistulous tract may be asymptomatic but, nevertheless, should be treated!

The initial sign is widening of the periodontal ligament space with preservation of the radio- opaque lamina dura. This naturally progresses with time to form a rounded periapical radiolucency with a not well-defined margins in Per. Cht gr. Diffusa and well-defined margins in Per. Cht gr. localisata - a . Ultimately, this may undergo cystic change to radicular cyst. Differentiation between a large granuloma and a small radicular cyst is not possible on purely radiological grounds, but lesions greater than 0,8/1 cm diameter are often assumed to be cysts until histopathological diagnosis is established. Differential diagnosis of chronic periapical periodontitis- different forms of chronic periodontitis,radicular cyst, , globulomaxillar cyst, tumour lesions, (odontogenic , myxoma, plasmocytoma, etc) Histological findings  Periapical granuloma consists of granulomatous inflammatory tissue infiltrated by mast cells, , lymphocytes  Periapical cysts have a central cavity filled with semisolid fluid lined by stratified squamous epithelium Management Once the infection has been resolved by extraction or appropriate endodontic therapy, the affected bone typically heals. Persistence of chronic periodontitis after is usually due to technical faults, and apicectomy may be required. Usually, a sinus tract resolves spontaneously after the offending tooth is extracted or endodontically treated. Sinus tracts that persist are thought to contain sufficient infectious material along the fistulous tract to maintain the surface granulation tissue, and surgical removal with curettage of the tract is required for resolution. Process of healing after RCT  After removal of irritants, inflammatory response tissue organization and maturation occur.  Bone that is resorbed is replaced by new bone, resorbed and dentin are repaired by cellular cementum  PDL that is first affected is restored in the last to normal

Per.chr. gr. diffusa sine/ cum fistula  RCT/Extraction  Incision and drainage- if there is exacerbation  Hemisection, root amputation  Apicectomy if needed

Per. Chr. Gr. localisata - simplex, epithelisatum, cysticum  Extraction and curettage  RCT and apicectomy(if needed)  Hemisection, root amputation CONDENSING OSTEITIS  A variant of asymptomatic apical periodontitis due to chronic irritation  Irritant from canal to periapical tissues is the cause  Mainly in mandibular posterior teeth mainly in young people  Occurs in association with apex of any tooth  Radiographically, radioopacity around root of tooth  Not respond to electric or thermal stimuli

Cysts  Cyst is defined as a pathological cavity filled with fluid, semisolid or gaseous form which is lined by epithelium  Cyst can occur within bone or soft tissues  They may be asymptomatic or associated with swelling and pain  Cysts are generally slow growing, expansive lesions  They grow by hydraulic expansion, PG E2, osmotic pressure  Radiographically, they often appear radiolucency surrounded by thin radioopaque border- linea albuginea The main factors in the pathogenesis of cyst formation are:  Proliferation of epithelial lining and fibrous capsule  Hydrostatic pressure of cyst fluid  Resorption of Surrounding bone Cysts of oral region

Epithelial Non Epithelial Lined Lined

Non Odontogeni odontogeni c c

Developmental Inflammatory

ODONTOGENIC

BASED ON ORIGIN BASED ON ETIOLOGY

1)REDUCED ENAMEL EPITHELIUM INFLAMMATORY - DEVELOPMENTAL CYST - -eruption cyst - of infants -residual cyst 2)CELL REST OF SERRE -gingival cyst of adults -paradental cyst -odontogenic - -gingival cyst of newborn -dentigerous cyst -gingival cyst of adults -eruption cyst -lateral periodontal cyst -lateral periodantal cyst -glandular -botryoid odontogenic cyst 3)CELL REST OF MALASSEZ -glandular odontogenic cyst -periapical cyst -calcifying odontogenic -residual cyst cyst 4)UNCLASSIFIED -calcified odontogenic cyst -paradental cyst

Radicular cyst is a true cyst and is a pathological cavity bounded by a connective tissue capsule lined with epithelial cells and filled with liquid content. This periapical cysts is the most common odontogenic cyst and is a result of proliferation of epithelial rests of Malassez induced by inflammatory and growth factors released by inflammatory cells found in chronic apical periodontitis following root canal infection and pulp necrosis. As a result of infectious irritation, a cystic cavity filled with liquid contents is formed. These cysts develop in both jaws, with a higher frequency in the frontal area. They are found mainly in the permanent dentition. Radicular cysts develop deep in the alveolar bone and have slow, asymptomatically growing. That’s why their detection is accidental during X-ray examination of non-vital teeth on another occasion. Radicular cysts grow slowly and can lead to mobility, root resorption and displacement of adjacent teeth. Radicular cysts could undergo asymptomatic evolution to significant sizes. Depending on the anatomical area in which they develop, the type and degree of clinical symptoms develop is different - swelling, dislocation of adjacent teeth, different degrees of sensory disturbances, crepitation, followed by erosion and fluctuation of the overlying soft tissues. Once infected, the cyst can cause pain and swelling, which alerts patients of an existing problem. Radiographically, radicular cyst appears usually as a well-circumscribed periapical radiolucent image in a tooth with pulp necrosis or tooth with bad endodontic treatment. A radicular cyst is considered a lesion that develops usually from a dental granuloma. As a result of infectious irritation, epithelial cell rests of Malassez proliferate within the granulation tissue. The epithelial cell rests degenerate, necrotize and liquefaction occurs. A cystic cavity is formed, filled with fluid contents and lined with multilayered squamous epithelium. In the presented case, in addition to the liquid contents, a formation with bone density and structure is detected histologically and macroscopically in the cyst cavity. The available mass is made up of bone structures with signs of degeneration.Conventional radiographic image showed a nonspecific and uncharacteristic of a radicular cyst image resembling chronic diffuse periodontitis. Microscopically, the radicular cyst presents a cystic cavity usually lined by non-keratinized stratified squamous epithelium. The epithelial thickness varies depending on the stage of the lesion and the inflammatory reaction level in the fibrous capsule. Dystrophic calcifications may be observed. A study evaluated a series of residual cyst formations and revealed that mineralization increases with time but the amount of calcifications usually does not reflect in mixed radiographic image. But in our case it was not dystrophic calcification but bone sequestrum. It was considered several theories for its formation including chronic inflammation, hypochlorite exposure inside the lesion during endo treatment, trauma, etc. Several diseases of the jaws may appear as a well-delimited mixed radiographic image. Ossifying fibroma, adenomatoid , keratocyst, apical scar, calcifying cystic odontogenic tumor, calcifying epithelial odontogenic tumor and osseous dysplasia should be considered as a differential diagnosis. Radiographic features

 LOCATION: In most cases the epicenter of a radicular cyst is located approximately at the apex of a nonvital tooth.  PERIPHERY AND SHAPE: The periphery usually has a well-defined cortical border. It will become ill-defined if infected.  INTERNAL STRUCTURE: In most radicular cysts is radiolucent.  EFFECTS ON SURROUNDING STRUCTURES: If a radicular cyst is large, displacement and resorption of the roots of adjacent teeth.

Diagnosis is based on the combination of:  Adequate History  Clinical Examination  Selected Investigation: Pulp vitality testing of associated teeth Radiographs (intra/extra oral) Aspiration and analysis of cyst fluids Histopathology Management Treatment of a tooth with a radicular cyst may include:  Extraction,  Endodontic therapy,  Apical surgery (Enucleation/Marsupilisation) The treatment of chronic periapical lesionsis endodontic treatment and follow-up of the patient until complete recovery of the bone lesion, but in case of true radicular cyst it is necessary to carry out a surgical treatment –enucleation of the periapical granuloma/cystic formation and provision of the samples for histological examination. Residual cyst  Residual cyst is retained periapical cysts from teeth that have been removed CLINICAL FEATURES . Usually asymptomatic and found on routine radiographic examinations . It is found in tooth bearing area RADIOGRAPHIC FEATURES . It may present well defined radiolucency that can vary in size from a few mm to several cm; with thin radioopaque margins DIFFERENTIAL DIAGNOSIS . Primordial cyst . Keratocyst . Traumatic cyst . Treatment: . -surgical removal Dentigerous cyst Central Lateral Circumferential  A cyst that forms around the of UNERUPTED tooth. It begins when fluid accumulates in the layers of REDUCED ENAMEL EPITHELIUM or between the epithelium and the crown of unerupted tooth.  Encloses crown of impacted / unerupted tooth and is attached to tooth cervix (enamel-cementum junction)  Mandibular 3rd molar, maxillary canine and maxillary 3rd molars most common are affected. Clinical presentation: 1. Asymptomatic. 2. swelling or pain. 3. Common in 4. Mandibular 3rd molar, maxillary permanent canine and mandibular . 5. More common in adult male 6. 20-50 years. 7. Permanent dentition may be missed 8. Large cyst may cause bone expansion and tooth displacement 9. may associated with supernumerary teeth or Radiographic Features - well-defined - unilocular or occasionally multilocular radiolucency with linea albuginea - associated with crown of unerupted tooth which is often displaced - resorption of roots of adjacent

Differential Diagnosis 1)hyperplastic follicle - -size of normal follicle space is 2-3mm - -If the follicular space exceeds 5mm associated with tooth displacement and bone expansion, a dentigerous cyst is more likely. 2)odontogenic keratocyst - OKC does not expand the bone to the same degree as dentigerous cyst, less likely to resorb tooth, may attach further at apically on the root instead of CEJ. 3)ameloblastic fibroma 4)ameloblastoma - -dentigerous cyst contain internal structure(tooth) 5)adenomatoid odontogenic tumor and calcified odontogenic cyst - -evidence of a radiopaque internal structure in these two lesion. Treatment: - Enucleation - Marsupialization and enucleation. marsupialization of cyst: . allow for decompression and subsequent shrinkage of lesion . reducing extent of surgery at a later date

ERUPTION CYST Eruption cyst is defined as an odontogenic cyst that surrounds a tooth crown which has erupted through bone but not soft tissue and is clinically visible as a soft fluctuant mass on the alveolar ridges - found in children of different ages, and occasionally in adults if there is delayed eruption - Lesion appear as circumscribed, fluctuant, bluish translucent swelling of the alveolar ridge over the site of the erupting tooth - When the circumcoronal cystic cavity contains blood, swelling appears purple or deep blue; hence the term ERUPTION HAEMATOMA - SITE: most commonly associated with the first permanent, molars and the maxillary incisors. GINGIVAL CYST  A small developmental extra-osseous odontogenic cyst of the gingival soft tissue derived from the rests of the dental lamina  Slowly enlarging, well circumscribed painless swelling.  on facial aspect of attached gingiva and gingival papilla.  Site: mandibular bicuspid/cuspid/incisor area.  Newborn; adult CLINICAL FEATURES . Small discrete white swellings of the alveolar ridge . Lesion is small, well-circumscribed , painless, swelling of the gingiva . Lesion is of same color as the adjacent normal mucosa and 1cm in diameter

Dental lamina cyst of newborn Lesion appear to be asymptomatic and do not produce discomfort in infant These are multiple , occasionally solitary, superficial raised nodules on edentulous alveolar ridges of infants that resolve without treatment, derived from rests of the dental lamina and consisting of keratin-producing epithelial lining Uncommon . Multiple superficial nodules . Resolve without treatment . Thin keratinized squamous epithelium DIFFERENTIAL DIAGNOSIS: Lateral periodontal cyst. Treatment- Gingival cyst in adult- excision ODONTOGENIC KERATOCYST A cyst derived from the remnants of the dental lamina, with a distinctive lining of six to ten cells in thickness and exhibits a basal cell layer of palisaded cells and a surface of corrugated parakeratin The WHO has reclassified this cystic lesion into a unicystic or multicystic odontogenic tumor on the basis of TUMORLIKE CHARACTERISTIC of the lining epithelium. The epithelium in the KOT appear to have innate growth potential, consistent with benign tumor. The epithelial lining is DISTINCTIVE because it is KERATINIZED (hence the name)and thin (4-8 cells thick).Occasionally, budlike proliferations of epithelium grow from the basal layer into the adjacent connective tissue wall. Islands of epithelium in the wall may give rise to SATELLITE MICROCYST. Inside the cyst contain a viscous or cheesy material derived from epithelial lining. Clinical feature: 1. 1st peak 20- 30 years and the 2nd peak 50-70 years . 2. Male predominance . 3. 2/3 in the mandible in the posterior alveolar ridge . 4. In the maxilla , the 3rd molar region is more affected . 5. Cyst have remarkable growth potentiality . 6. Grow in antero-posterior direction 7. Usually single , occasionally multiple ( Golin –Gottz syndrome ). 8. Small cyst discovered incidentally by X-ray . 9. Large cyst cause bone swelling 10 . Pain, mobility and displacement of teeth . 11. Occasional paresthesia of lower and teeth . 12. In some cases extraosseous extension to gingiva. 13. may associated with UNERUPTED tooth. - aspiration reveal a thick yellow cheesy material(KERATIN) Have high properties of RECCURENCE ,because of small satellite cyst or epithelium fragments left behind after surgical removal of epithelium 1. High and remarkable growth potential . 2. May attain a large destructive size. 3. High recurrence rate after enaculation 25-60% 4 . Recent WHO classification designates this cyst as Keratocystic adontogenic tumor I case of paraceratosis of the epithelium - may exhibit aggressive clinical behavior - significant recurrent rate - associated with nevoid basal cell carcinoma syndrome- Gorlin –Goltz syndrome Causes of recurrence: 1. Thin fragile lining . 2. Budding or finger like cyst . 3. Daughter cysts . 4. Other dental lamina 5. Focal separation of the epithelium Radiographic Features -can radiographically mimic other types of cysts

- well-circumscribed radiolucency - with smooth radiopaque margins - most lesions are unilocular or multilocular - the epicenter located superior to inferior alveolar nerve canal

Internal Structure: - -radiolucent - -in some case curved internal septa may be present giving a multilocular appearance.

Periphery and shape -well-defined cortical border -smooth round or oval shape -or might have scalloped outline Effect on surrounding structure: -a very characteristic feature that its PROPENSITY TO GROW ALONG THE INTERNAL ASPECT OF THE JAW CAUSING MINIMAL EXPANSION. -this occur throughout the mandible except for the upper ramus and coronoid process. -the relatively slight expansion contributes to their late detection, which allow them to reach a large size. - it can displace and resorb teeth but to a slightly degree than dentigerous cyst. -the inferior alveolar nerve canal may be displaced inferiorly. -this may invaginate and occupy the maxillary antrum. - 40% was noted to be adjacent to crown of unerupted teeth

DIFFERENTIAL DIAGNOSIS . Dentigerous cyst . Ameloblastoma . Primordial cyst . Residual cyst . Traumatic cyst . Benign odontogenic tumor . Giant cell granuloma . Odontogenic myxoma Treatment & Prognosis - surgical excision with curettage and peripheral osteotomy 1. Small: Simple enaculation. 2. Large: Enucliation with or without peripheral osteomy. 3. Other treatment options: Complete resection with 1cm margin 4. 2 steps treatment:1.Decompression. 2.Cystectomy Long term follow up is needed LATERAL PERIODONTAL CYST A slow growing, non- expansile developmental odontogenic cyst derived from one or more rests of the dental lamina, containing an embryonic lining of one to three cuboidal cells and distinctive focal thickenings  Uncommon intra-osseous odontogenic cyst  It’s derived from rest of dental lamina  Lateral to the root surface of erupted tooth CLINICAL FEATURES . Predilection for occurrence in males . Site: mandibular bicuspid/cuspid/incisor area . When the cyst is located on labial surface of the root, there is a slight mass . May produce bone expansion and pain . Tooth is vital . . Usually less than 1 cm . . teardrop-shaped unilocular radiolucency with opaque margin along lateral surface of vital tooth root . Lesion is small, border is definitive and surrounded by thin layer of sclerotic bone Differential diagnosis . Primordial cyst . Globullomaxillary cyst . . Small OKC . Mental foramen . Small neurofibroma . Lateral radicular cyst

Treatment Surgical excision of cyst. Primordial Cyst - arises from cystic changes in developing tooth bud - before formation of enamel and dentin matrix - since it arises from tooth bud, tooth will be missing from dental arch - unless cyst arose from supernumerary tooth - usually found in children and young adults between 10 years and 30 years of age Radiographic Features - circular radiolucency - with radiopaque border with sclerotic or reactive border - found at site where tooth failed to develop - more in relation to 3rd molars Treatment - Radical Surgery- enucleation with curettage

Botryoid odontogenic cyst (BOC) was originally described in 1973 by Weathers and Waldron as an intraosseous lesion characterized by a macroscopic and microscopic multilocular growth pattern, resembling a bunch of grapes (from the Greek word botrios)  A botryoid odontogenic cyst is considered to be a rare multilocular variant of a lateral periodontal cyst.  Rare odontogenic cyst resembles the cluster of grapes .  Cystic changes of multiple adjacent dental lamina  Polycystic variant .  Expensile , painless central swelling .  Multilocular cysts with fine septa.  Flat nonkeratinized epithelium with clear cells  Strong tendency to recurrence Differential diagnosis: botryoid odontogenic cyst, glandular odontogenic cyst, and lateral periodontal cyst, OKC etc.  Recurrences of multilocular radiolucent lesions of BOC are common. A non- conservative surgical removal is the only effective treatment for this kind of lesion. GLANDULAR ODONTOGENIC CYST . A large solitary or multilocular odontogenic cyst derived from rests of dental lamina, consisting of a stratified squamous epithelium containing numerous mucus-secreting cells. . A slight male predilection . Common site is anterior mandible . Lesion shows slow progressive growth, painless and locally destructive . Intra osseous from dental lamina. . Large single unilocular or multilocular . Anterior mandible. . Uni or multilocular radiolucent. . Thin stratified squamous with small glandular or microcyst (Pseudo-duct like) . High tendency to recurrence CALCIFYING ODONTOGENIC CYST A rare, well circumscribed, solid or cystic lesion derived from odontogenic epithelium that contains ghost cells and spherical calcifications . The central lesion may appear as a cyst like radiolucency with variable margins which may be smooth well defined or irregular in shape with well-defined borders . evidence of small foci or calcified material that appear as white flecks or small smooth pebbles . Perforation of cortical plates can be seen . 75% occur in bone anterior to first molar especially associated with cuspids and incisors DIFFERENTIAL DIAGNOSIS . Fibrous dysplasia . Partially calcified . Adenomatoid odontogenic tumor . Ossifying fibroma . Odontogenic fibroma . . Dentigerous cyst . Ameloblastic fibroadenoma Calcifying epithelial odontogenic tumor Traumatic  Children and adolescent.  Mandibular premolar and molar  Painless swelling .  Round radiolucent and less sharply defined .  Bony wall lined by thin loose C.T ,RBCs or hemosedrin laden macrophages  Unknown PARADENTAL CYST- Buccal bifurcation cysts PARADENTAL CYST is an inflammatory cyst which develops on the lateral surface of a tooth root Most common in the 6- to 11-year-old age group( first third decade )  Usually associated with the mandibular first molar, occasionally the mandibular second molar; third molar association- distally to 3rd mandibular molar with .  The associated tooth has an altered eruption pattern with buccal tilting of the crown.  The associated tooth is vital.  Deep periodontal pockets on the buccal aspect of the tooth.  +/- swelling in buccal aspect  +/- pain or tenderness  +/- infection. DIFFERENTIAL DIAGNOSIS can be considered:  A periodontal pocket  periostitis ossificans  dentigerous cyst  lateral radicular cyst  Langerhan’s cell histiocytosis Surgical removal of the tooth and the PC has been considered the treatment of choice when the involved tooth is a third molar.  Enucleation of the lesion with the maintenance of the associated tooth, can be recommended when the first or second molars are involved, in an attempt to preserve the important permanent teeth in the mandibular arch. Complete removal is advocated although to date, recurrences have not been reported  There is also the possibility of spontaneous drainage, leading to the regression of the lesion by depressurization and spontaneous healing NON ODONTOGENIC CYSTS Bone fusion between maxilla and premaxilla Cyst between maxillary lateral incisor and canine Asymptomatic unless infected. Pseudostratifeid columnar or squamous Pathogenesis . - between lateral incisor + canine teeth - many are lined by inflamed stratified squamous epithelium - Inverted pear shaped radiolucent cyst . Treatment- enucleation - I- st theory arising from epithelial remnants entrapped along line of fusion of: • maxillary • median nasal • lateral nasal process

II-nd theory- Remnant of nasolacrimal duct

It is rare developmental cyst occurs in upper lateral to midline Clinical Features:  Age:12-75 years  Sex: female predilection  Usually UNILATERAL a) small lesion  -very subtle, unilateral swelling of  nasolabial fold associated with  pain or discomfort. b) large lesion  -it may bulge into floor of nasal  cavity causing obstruction, flaring  of alae,distortion of nostrils  and fullness of upper lip.

Treatment & Prognosis - complete surgical excision of cyst via intraoral approach - because lesion is often close to floor of nose sometimes it is necessary to make excision of part of nasal mucosa to ensure total removal Median Palatal Cyst- develops from epithelium entrapped along embryonic line of fusion of lateral palatal shelves of maxilla

Clinical Features - firm or fluctuant swelling of midline of hard posterior to palatine papilla - most frequently in young adults - often asymptomatic occlusal radiographs demonstrate well-circumscribed radiolucency in midline of hard palate Treatment - surgical removal - recurrence should not be expected Nasopalatine Duct Cyst - also known as Incisive Canal Cyst - most common non-odontogenic cyst of oral cavity - believed to arise from remnants of nasopalatine duct - embryologic structure - connects oral + nasal cavities in area of incisive canal Occasionally, a cyst forms in the nasopalatine canal when these embryonic epithelial remnants of the nasopalatine duct undergo proliferation and cystic degeneration. Pressure of cyst on adjacent nasopalatine nerve may cause burning sensation or numbness over palatal mucosa.  Asymptomatic  The most common nonodntogenic  Remnant of nasopalatine duct.  Slow growing swelling in the anterior region of midline palate.  Intermittent salty discharge.  Should differentiated from Incisive papillae  If extends posteriorly involving hard palate  well-circumscribed radiolucency in or near midline of anterior maxilla  lesion most often is round or oval with a sclerotic border in some cases, a classic heart shape • result of superimposition of nasal spine • OR because they are notched by nasal septum - radiolucency that is 6 cm or smaller in this area is usually considered a normal foramen Differential diagnosis unless other clinical signs or symptoms are present 1) large incisive foramen - -cyst is presumed when the width of foramen exceeds 1cm and cause tooth displacement. 2) a radicular cyst or granuloma - -absence of lamina dura and enlargement of periodontal ligament space around apex of central incisors indicate an inflammatory lesion. - -vitality test - -a second periapical view taken at different horizontal angulation should show altered position of a nasopalatine duct cyst, whereas radicular cyst should remain centered about the apex of central incisors. - benign + malignant lesions have been known to mimic nasopalatine duct cyst Management: - -enucleation -marsupialization- indicated for large cyst Important for Cyst!!! Sharpe radiolucent with well-defined margin. Fluid may be aspirated. Tran-illuminated. Grow slowly Displacing rather than resorbing. Symptomless. Rarely cause pathological fracture Forms compressible and fluctuant swelling. Appears plush close to the mucosa. Cystic epithelium some time undergo neoplastic transformation. Cysts- Approach of diagnosis Complete history: Pain, duration, tooth mobility or loss occlusion ,swelling , delay eruption Physical examination: Inspection, palpation, percussion. Radiology: Plan X-ray, panoramic, dental radiograph, CT, Pulp sensitivity test Describing the Lesion 1. Size 2. Shape 3. Location 4. Density 5. Borders 6. Internal Architecture 7. Effect on adjacent structures FNAC: Pathohistological examination

Reference

1. Burket's diagnosis and treatment; Greenberg M, Glick M, tenth edition; 2003 BC Decker Inc 2. Cawsan 's essentials of oral and oral medicine, R.A. Cawson, Odell E. W., Porter S, Seventh edition, 2002, Elsevier 3. Cysts of the oral and maxillofacial regions; Shear M, Speight P; 4th ed., Blackwell Publishing Ltd 4. Oral and maxillofacial pathology-a rationale for diagnosis and treatment, first edition, Marx R, Stern D, 2003,Quintessence Publishing Co 5. Oral and maxillofacial pathology, Neville,Damm,Allen,Bouquot, Third edition, Saunders Elsevier 6. Oral and maxillofacial surgery, radiology, pathology and oral medicine; Coulthard P, Horner K, Sloan P, Theaker E; First edition; 2003, Elsevier Science 7. Oral medicine and pathology at a glance; Scully C, de Almeida O, Bagan J, Dios P.D.;Wiley-Blackwell,2010 8. Oral surgery, Fragiskos D.F., Springer,2007 9. Peterson's principles of oral and maxillofacial surgery; Miloro M,Second Edition,2004, BC Decker Inc 10. Pocket atlas of oral diseases, Laskaris G, Second edition, Thieme

11. Oral and maxillofacial surgery, radiology, pathology and oral medicine; Coulthard P, Horner K, Sloan P, Theaker E; First edition; 2003, Elsevier Science 12. Oral and maxillofacial pathology, Neville,Damm,Allen,Bouquot, Third edition, Saunders Elsevier