Mixed radiopaque & radiolucent lesions of jaw

the presentation deals with the various mixed radiopaque and radiolucent lesions of jaw. it covers important topics useful in bds curriculum.

1. GOOD MORNING

2. Seminar on Mixed radiopaque – radiolucent lesions By Samarth johari

3. Definitions Radiolucent : It refers to that portion of a processed radiograph which appears as dark / black. It is caused due to the passage of maximum photons through the objects. Radiopaque : It refers to that portion of processed radiograph which appears as light / white. It is caused due to the presence of dense objects in path of photons that are strong absorbers.

4. Why Mixed???? Some normal anatomic structures and disease states can produce mixed radiolucent and radiopaque images on radiographs. Some pathology may be present as an osteolytic lesion , which appears as radiolucency in radiograph . During it’s development, foci of calcified material may form within the osteolytic area.

5. When these foci become large and mineralized, they become radiographically apparent. Thus, mixed radiolucent & radiopaque condition frequently represents an intermediate stage in development of lesion .

6. Mixed Radiolucent – Radiopaque Lesions Cementoma Calcifying epithelial odontogenic cyst Calcifying epithelial odontogenic tumor Adenomatoid odontogenic tumor

7. CEMENTOMA : Also known as – Periapical cemental dysplasia Fibrocementoma Sclerosing cementum Periapical osteofibrosis Periapical fibrosarcoma Periapical fibrous dyplasia Periapical fibro – osteoma Defined as – a reactive fibro–osseous lesion derived from the odontogenic cells in the periodontal ligament. Located at – apex of tooth.

8. Clinical features – More common in females, blacks & in middle age. Age group : middle age. Common in mandibular anterior region. Asymptomatic & involved tooth is vital. Usually diagnosed during routine checkup. Small in size ( <1cm in diameter) but may become quite large causing expansion of alveolar process. Early phase – resorption of normal bone ( radiolucent phase ) Developing phase – abnormal bone manufactured within lesion (mixed radiopaque & radiolucent phase) Late / mature phase – internal structure dominated by abnormal bone.

9. Radiographic features - Location : Epicenter lies at apex of tooth. Mostly lesion is multiple & bilateral. Periphery & shape : Well defined periphery. Radiolucent border of varying width, surrounded by varying width of sclerotic bone. May be irregular in shape or round or oval shaped centered over apex of tooth. Internal structure : Stage 1 – osteolytic stage : Radiolucency ( 1cm in diameter ) in periapical region More than 1 tooth may be involved.

10. Stage 2 – cementoblastic stage : small areas of calcification develops within radiolucency.

11. Stage 3 - Mature stage: Individual calcified mass increase in size Masses unite with adjacent lesions to form single large radiopaque mass with thin radiolucent line in periphery

12. Effects on surrounding structures : Adjacent teeth are not displaced No root resorption of adjacent teeth are seen Adjacent teeth are vital, with intact PDL space, lamina dura may be discontinuous No expansion of jaw is seen Differential diagnosis – Periapical rarefying osteitis – in early stages, PCD can not be ruled out radiographically alone. Thus, final diagnosis is based on vitality of involved tooth.

13. Benign cementoblastoma & odontoma – Cementoblastoma : solitary, attached to surface of root which may be partly resorbed. better defined peripheral soft tissue capsule

14. Odontoma : starts occlusal to a tooth prevents eruption resembles tooth like structure more uniform in width & better defined than the periphery of PCD

15. Management - Periodic radiographic evaluation (watchful neglect) Surgical enucleation indicated in cases of expansion of cortical plates.

16. 2. CALCIFYING EPITHELIAL ODONTOGENIC CYST : Also known as – Calcifying odontogenic cyst G orlin’s cyst Defined as – an unusual lesion with features suggestive of a cyst & characteristics of a solid neoplasm. Clinical features – females > males 3/4 th of the lesion occurs centrally, 75% occuring anterior to the 1 st molar. Affects both jaws equally. Slow growing, asymptomatic. May cause expansion or destruction of cortical plates.

17. Adjacent teeth may be displaced. May be associated with an odontoma & may have calcified material identified as dysplastic dentine. Aspiration yields a viscous,granular , yellow fluid. Radiographic features – Location : Anterior to 1 st molar Associated with cuspids & incisors, where it may manifest as pericoronal radiolucency periphery & shape : Vary from well defined & corticated with curved, cyst like shape to ill defined & irregular.

18. Internal structure : may be completely radiolucent or may show evidence of small foci of calcified material that appear as white flecks or small smooth pebbles. Multilocular in rare cases. Effect on surrounding structures : Most commonly associated with cuspid Displacement of teeth may be seen Root resorption is present Perforation of cortical plates in enlarged lesions

19. It may resorb roots of adjacent teeth. Radiolucency may contain small foci of calcified material seen as white flecks or smooth pebbles ( radiopacities ). At times the entire lesion may be occupied by the calcific body & thus appear radiopaque.

20. Differential diagnosis – Fibrous dysplasia – appears as mottled or has a smoky defined borders, more common in maxilla . Odontoma – surrounded by a capsule .

21. AOT – in the intermediate stage of development, AOT appears like a CEOC.

22. Cementoblastoma – well defined radiographic image attached to the root of the tooth. Management – Enucleation with curettage Regular follow - up

23. 3. CALCIFYING EPITHELIAL ODONTOGENIC TUMOR : Also known as – Pindborg’s tumor Ameloblastoma of unusual type with calcification Defined as – rare tumor of distinctive microscopic appearance that appears to arise from the reduced enamel epithelium or dental epithelium. Clinical features – Accounts for 1% odontogenic tumor. Males > females Age range : 8-92 yrs. Mandible > maxilla Common in premolar – molar region Rarely may have extraosseous location.

24. Usually asymptomatic. May be associated with paresthesia . Associated with unerupted teeth. Cortical expansion is common. Palpation indicates hard swelling with well defined or diffused border. Simulates ameloblastoma , less aggressive but locally invasive. Rate of recurrence is high. Radiographic features – Location : Mandible > maxilla More common in premolar – molar area Periphery : Well defined cyst like cortex Irregular & ill defined border

25. Internal structure : May be unilocular or multi locular ( HONEYCOMB PATTERN ) Numerous scattered, radiopaque foci of varying size & density are seen. Small thin, opaque trabaculae cross radiolucency in many direction ( DRIVEN SNOW APPEARANCE ) Effects on surrounding : May displace developing Tooth & prevent eruption Expansion of jaw with maintenance of cortical boundary may occur

26. Differential diagnosis – AOT – more common in anterior maxilla as compared to CEOT, which is common in the mandibular premolar – molar region. Calcifying odontogenic cyst – aspiration yields vicous , granular, yellow fluid. O dontoma – has a capsule. Management – Conservative treatment with local ressection with limited margins.

27. 4. ADENOMATOID ODONTOGENIC TUMOR : Also known as – Adenoameloblastoma Ameloblastic adenomatoid tumor Defined as – an uncommon, non aggressive tumor of odontogenic epithelium, with a duct like structure & varying degree of inductive changes in connective tissue. Classified as – Peripheral adenomatoid odontogenic tumor Central adenomatoid odontogenic tumor – a. follicular type b. extra follicular type

28. a. follicular type – associated with embedded tooth b. extrafollicular type – not associated with embedded tooth. Clinical features – Females > males Age range : 5-50yrs Maxilla > mandible More common in anterior cuspid region Asymptomatic Slow growing swelling Associated with unerupted tooth Expands cortices but is non - invasive

29. Radiographic featurers – Location : More common in incisor – canine – premolar region May have follicular relationship with impacted tooth Does not attach at CEJ Surrounds greater part of tooth

30. Periphery : Well defined corticated, sclerotic border Internal structure : Completely radiolucent or may contain faint radiopaque foci Occasionally, small calcifications with well defined borders, like cluster of small pebbles Effects on surrounding structures : Displacement of adjacent Teeth Root resorption is rare Prevents eruption Expansion of jaw may Appear but outer cortex is maintained

31. Differential diagnosis – CEOC – occurs in older age group, usually in premolar region. CEOT – more common in posterior mandibular region.

32. Ameloblastic fibro – odontoma – more common in posterior mandible region, is multilocular & radiopacities of enamel & dentine are seen inside the radiolucency. Whereas, in AOT snow flecks are seen in periphery.

33. Odontogenic fibroma or myxoma – TENNIS RACKET appearance is seen. Management – Conservative surgical excision with curettage.