Dent 356-11 Laboratory Session 6 Inherited, Developmental, Inflammatory, Metabolic Disorders of Bone

1. Dent 356-11 Laboratory Session 6Inherited, Developmental, Inflammatory, & Metabolic Disorders of Bone Dr. Huda Hammad

2. Osteogenesis Imperfecta:Clinical Features Sclerae may appear blue because they are so thin that the choroid shows through. Joint hypermobility with lax ligaments.

3. Osteogenesis Imperfecta:Clinical Features Dentinogenesis imperfecta may be associated with some cases.

4. Osteopetrosis (Marble Bone Disease):Clinical Features Two basic patterns: 1. Malignant type: Progressive Autosomal recessive Occurs early in life Severe bone fragility and malformations Death usually before puberty. 2. Benign type: Autosomal dominant Less severe Diagnosis may not be made until late in life and incidentally. Repeated fractures following minor trauma

5. Osteopetrosis (Marble Bone Disease)Radiographic Features Increased density of skeleton. Lack of distinction between cortical and medullar bone. Marked density of base of skull. Mandible more involved than maxilla. Roots of teeth may be invisible.

6. Osteopetrosis (Marble Bone Disease):Histopathologic Features Thickened cortices. Reduced marrow cavities. Persistence of woven bone. Marked lack of mature lamellar bone.

7. Cleidocranial Dysplasia (Cleidocranial Dysostosis):Clinical Features Abnormalities of skull: Fontanelles and sutures tend to remain open. Skull appears flat with prominent frontal, parietal, and occipital bones. Nasal bridge is depressed. Maxilla may be underdeveloped with a high, narrow arched palate.

8. Cleidocranial Dysplasia (Cleidocranial Dysostosis):Clinical Features Partial or complete absence of clavicles allows shoulders to be approximated until they meet.

9. Cleidocranial Dysplasia (Cleidocranial Dysostosis):Clinical Features Dental abnormalities: Deciduous dentition tends to be retained with delayed or non-eruption of permanent dentition because of multiple impactions. Supernumerary teeth and dentigerous cysts are common. Roots tend to be thinner than normal. Secondary cementum is sparse or absent on both dentitions.

10. Monostotic Fibrous Dysplasia of Bone:Clinical Features

11. Monostotic Fibrous Dysplasia of Bone:Radiographic Features Jaw lesions are variable in appearance, reflecting differing amounts of metaplastic bone formed within fibrous tissue. Borders are difficult to define because of gradual transition to normal. Initially resemble cyst-like radiolucencies containing faint bony trabeculae. With increasing trabeculation, they become mottled and eventually opaque.

12. Monostotic Fibrous Dysplasia of Bone:Radiographic Features The many delicate trabeculae give a ground-glass or orange-peel-stippling effect. In some lesions, coarse mottling of smoke-screen pattern produced by irregular radiopaque masses lying in a radiolucent background. In the maxilla, lesions may extend up to and distort, but do not cross suture lines. Roots of teeth in involved areas may be separated and teeth may be displaced, but root resorption is exceptional.

13. Polyostotic Fibrous Dysplasia of Bone:Clinical Features May present as part of Albright syndrome: Very uncommon. Café-au-lait melanotic spots on skin. Precocious puberty in females. Occasionally other endocrine abnormalities. Premature skeletal maturation. Pigmentation of oral mucosa reported. Occurs in males without precocious puberty.

14. Fibrous Dysplasia of Bone:Histopathologic Features Replacement of normal bone by fibrous tissue containing islands and trabeculae of metaplastic bone. Appearances of jaw lesions are more variable than in other bones. Fibrous tissue may be richly cellular and show a whorled pattern, or may consist of thick, interlacing collagen bundles. Newly formed bony trabeculae are delicate and irregular (likened to Chinese characters). They consist of immature, coarse-fibered woven bone.

15. Fibrous Dysplasia of Bone:Histopathologic Features In jaw lesions, trabeculae may be thicker and blunter than in long bones. Spherical areas of calcification resembling cemetum may be present. Osteoblastic and osteoclastic activity may be seen in relationship to some trabeculae. At the margins, lesional bone fuses with normal bone and this particular features distinguishes FD from ossifying fibroma. Usually with increasing age, the amount and cellularity of fibrous tissue decreases and the amount of bone increases.as the lesion matures, there is progressive remodelling of woven bone to lamellar bone. Occasionally, the lesion may be associated with development of aneurysmal bone cyst.

16. Florid Cemento-osseous Dysplasia: Radiographic Features Poorly demarcated, dense, lobular, radiopaque masses.

17. Cherubism

18. Cherubism: Clinical Features Progressive reduction in deformity as the patient passes from puberty into adult life. Cosmetic surgery is often needed to deal with residual deformity.

19. Cherubism: Radiographic Features Sharply defined, multilocular radiolucencies. Expansion and thinning of cortical plates, even perforation. Mandibular lesions appear to begin near the angle and spread to involve the body and ramus. Maxillary lesions are often confined to tuberosities, but sinus may be obliterated.

20. Cherubism: Histopathologic Features Cellular and vascular fibrous tissue containing varying amounts of multinucleated giant cells. The appearance is similar to other giant cell lesions of the jaws, and differentiation between them requires clinical and radiographic information. As the activity of the lesion decreases, it becomes more fibrous, giant cell number diminishes, metaplastic bone is deposited.

21. Focal Sclerosing (Condensing) Osteitis Generally seen at root apex, most commonly 1st permanent molar. May remain after extraction. Usually asymptomatic.

22. Suppurative Osteomyelitis:Clinical Features Chronic: Discharge of pus through one or more intraoral or extraoral sinuses.

23. Suppurative Osteomyelitis:Radiographic Features Normal in early stages. In 10-14 days, sufficient bone resorption occurs to produce irregular, moth-eaten areas of radiolucency. Sequestra may be seen.

24. Suppurative Osteomyelitis:Histopathologic Features Suppurative osteomyelitis, note the devitalized lamellar bone sequestrum with scalloped edges and absence of stainable osteocytes and osteoblasts. An osteoclast in a resorption area is seen.

25. Chronic Sclerosing Osteomyelitis A controversial condition: - localized lesions are identical to focal sclerosing osteitis. - some previously reported diffuse types probably represent infected florid cemento-osseous dysplasia. However, diffuse sclerosing lesions of the mandible as a complication of spread from contiguous focus of low-grade infection/inflammation such as periapical granuloma have been reported.

26. Chronic Osteomyelitis with Proliferative Periostitis(Garré’s Osteomyelitis, Periostitis Ossificans) Radigraphs show focal subperiosteal overgrowth of bone with smooth surface on outer cortical plate. The subperiosteal mass consists of irregular trabeculae of actively forming woven bone with scattered chronic inflammatory cells in fibrous marrow.

27. Chronic Osteomyelitis with Proliferative Periostitis(Garré’s Osteomyelitis, Periostitis Ossificans) Periosteal new bone formation (periosteal reaction) / Onion-peel appearance.

28. Radiation Injury and Osteoradionecrosis

29. Radiation Injury and Osteoradionecrosis Extensive osteomyelitis with painful necrosis of bone, often associated with sloughing of overlying oral and sometimes facial soft tissues may occur, even years after radiotherapy.

30. Osteoporosis

31. Primary Hyperparathyroidism:Clinical Features* Severe cases may variably be associated with: Bone pain. Bone cysts (osteitis fibrosa cystica). Pathologic fractures. Brown tumors. Renal colics due to stones. Mental changes including depression, emotional liability, poor mentation, and memory defects. Increased incidence of peptic ulcer. Chronic pancreatitis. Hypertension.

32. Primary Hyperparathyroidism:Clinical Features*

33. Primary Hyperparathyroidism:Clinical Features Biochemical changes have to be demonstrated to confirm diagnosis. They are: Elevated parathomone level. Increased serum calcium level. Reduced serum phosphate level. Increased urinary excretion of calcium and phosphate There may be elevated alkaline phosphatase.

34. Primary Hyperparathyroidism:Histopathologic Features Increased osteoclastic activity throughout the skeleton. Fibrosis of marrow (osteitis fibrosa). Occasionally, focal areas of bone resorption result in formation of lesions called brown tumors. They are identical to other giant cell lesions of the jaws.

35. Primary Hyperparathyroidism:Radiographic Features May show no detectable changes or generalized osteoporosis. Brown tumors present as sharply defined, round or oval radiolucent areas.

36. Primary Hyperparathyroidism:Radiographic Features Partial loss of lamina dura around roots of teeth may occur. Brown tumors present as sharply defined, round or oval radiolucent areas. They may be multilocular. They occur more frequently in the mandible than in the maxilla.

37. Rickets and Osteomalacia

38. Acromegaly