Radiology Sheet #4 By Zaid Al-Zu'bi

by **Sura** 31/10/2012, 1:53 am

http://www.4shared.com/file/TWEBQQFc/radio_zaid.html

by **Shadi Jarrar** 9/11/2012, 4:55 pm

Radiology

This lecture is going to be talking about systemic diseases manifested in the jaws, meaning that signs and symptoms of such diseases are not exclusive to the head and neck region, instead, it’s rather systemic, particularly they have generalized bony effects, this also means that the effect we see in the mandible is the same we see in long bones, cervical spine…etc.

- As radiographic features, these diseases might show change in the size and shape of the bone, change in the number, size, and orientation of the trabeculae, change in the thickness and density of the cortical structures, bony density changes, tooth related changes…etc. all across the board.

Endocrine diseases:

1- Hyperparathyroidism :

- Excessive PTH.

- Primary: an enzyme secreting lesion in parathyroid (adenoma most common)

Secondary: more related to Calcium and phosphorus balance either inside the serum, or inside the bone, that’s governed by parathyroid gland.

Tertiary: if we treated the cause of the secondary hyperparathyroidism and still the level of PTH is high, then this is called tertiary hyperparathyroidism.

- So if we’ve got a high level of PTH, then we suspect that the bone density, strength, volume...etc. would be lower than normal, that appear radiographically as radiolucencies of different size and shape and distribution among all bones in body.

- Represented with generalized demineralization and loss of cortical bone, ill-defined radiolucent areas, very small randomly oriented trabeculae, lower bone density, brown tumor and loss of lamina dura.

- Brown tumor: it’s a misnomer; it’s rather a reactive central giant cell granuloma lesion appears brownish stained grossly because of its hemosiderin content due to its high vascularity. It’s been related to hyperparathyroidism because of bone osteoclasts that are being altered and turned out hyperactive in this regard causing this radiographic aspect.

- Q: How can I confirm that this particular hyperparathyroidism patient has brown tumor radiographically?

A: apart of other radiographic features as low bone density, volume, disrupted lamina dura, abnormal trabeculae…etc. brown tumor is more of a well-defined border, and isolated lesion, along with all other background differences.

- We can never differentiate under the microscope between CGCG and brown tumor; instead we rely on other signs of hyperparathyroidism as in calcium/phosphorus balance, if above normal calcium below normal phosphorus then we’re talking about hyperparathyroidism (that causes brown tumor).

- Malignancy, acute inflammation, and metabolic diseases may exhibit the same features radiographically, as in loss of cortical borders and lamina dura, so absolutely we can’t rely completely on a radiographic image to diagnose, we should consider other aspects of the diseases and judge accordingly. Plus, logical thinking can help out as well, it’s too odd to have a patient with malignancy for example in 4 quadrants of the jaw, or has osteomyelitis involving all his head and neck region, so here we may contemplate in something systemic rather than localized. And so on.

2- Hypopituitarism:

- Pituitary gland secretes growth hormone, among other hormones.

- If GH level goes up, then gigantism take place if the patient is still young, acromegaly if he is already grown up.

- Coarse soft tissues, abnormal extremities, large mandible (class 3)…etc.

- Radiographs show all these signs plus enlarged sella turcica if the adenoma was big enough to cause expansion.

- So enlarged sella turcica, enlarged Para nasal sinuses, thickening of outer border of skull, enlargement of the jaws, hypercementosis. Would indicate hypopituitarism.

3- Hyperthyroidism:

- Increase in T3 and T4 hormones that are responsible of body metabolism.

- High metabolic rate (HMR) might have some radiographic features so that we mentioned it in radiology.

- HMR is also accompanied by increase rate of development , pictured in the jaws as advanced dental development, early teeth eruption, early exfoliation of primary teeth, and sometimes (<5%) generalized decrease in bone density.

- Clinical signs and symptoms are the key for diagnosis, no certain radiographic feature that tells this is a hyperthyroidism patient.

4- Hypothyroidism:

- What happens is exactly the opposite of that of hyperthyroidism.

- Late closure of epiphysis, warmian bones in skull sutures, short roots, small jaws, periodontal disease, macroglossia and early loss of teeth in adults.

5- Osteoporosis:

- Affects generally elderly, in particular post-menopausal female society.

- It’s of concern because of fractures and pain it causes, that burden the society in general especially fractures in distal radius and proximal femur.

- Radiographically appears as reduction I bone density, thinning of cortical border. In mandible we notice this in the inferior border cortex (inf. Bord. Of mand.).

- Yet it could resemble for ex. hyperparathyroidism radiographically, no one would be sure of a certain disease by just looking at the radiograph, it’s more like all these fall in the one category of diseases (i.e. bony diseases) that require thorough examination beside the radiographs to be certain of your diagnosis.

- Areas of interest usually are the stress bearing areas; fractures mainly found there, they might be complicated to a more serious condition.\

6- Rickets and Osteomalasia:

- Both are the same, rickets occurs in childhood, Osteomalasia occurs later on.

- Basically the patient has reduced calcium and phosphorus levels as a result of abnormality of vitamin D metabolism.

- As dentist, I do expect dental anomaly in case of rickets patient, but not in osteomalasia because dental development simply takes place in childhood.

- Same radiographic features; reduced bone density, but if we noticed change in teeth mineralization or incomplete root or crown formation, then this goes more with rickets than osteomalasia for the same reason above.

7- Hypophosphatasia:

- Inherited disorder.

- Reduced production or defective function of alkaline phosphatase enzyme, which is required in normal bone metabolism.

- 3 subtypes: 1- Infantile: extremely bad, the infant dies in early age.

2- Childhood: milder than infantile.

3- Adulthood: the mildest and the most compatible with life.

- Epiphyseal defect, poorly calcified skull, premature skull sutures closure, brachiocephally, and generalized reduction in bone density.

- Thin enamel, large pulp, hypoplastic teeth that might be lost prematurely.

- Teeth in radiographs appear like ghost teeth, but the difference is that the later occurs in one quadrant and never in the entire dentition, so this leads our thoughts to be toward a systemic disease rather than localized.

8- Renal osteodystrophy:

- Chronic renal failure, causes bony changes that do not have particular pattern, instead, it might be more on the opaque side, or on the lucent side.

- For diagnosis, this needs thorough clinical exam, laboratory tests, and then radiographs may confirm.

9- Hypophosphatemia:

- Called vitamin D resistant rickets.

- Excessive loss of phosphorus, reduced level in the blood.

- Sometimes it accompanies multiple myelomas.

- Reduced growth rate with all the secondary features that go with that.

10- Osteopetrosis:

- Autosomal dominant, though it could be recessive.

- Building of bone excessively, cortical bone everywhere that gradually starts losing its vascularity.

- Foramina of the skull close, leading to central nerve lesions signs and symptoms.

- The bone is way too hard and way too dense to teeth to erupt, most of teeth don’t erupt and those which do don’t erupt to the full extent. So dental wise, we’re worried about impacted teeth the most.

- The jaws are very sensitive to infections and inflammation, highly susceptible to osteomyelitis, so extraction might be a big problem as well.

- Radiographic feature is bone within bone, for ex. You can find phalange within phalange, which is a good diagnostic sign to Osteopetrosis.

11- Sickle cell anemia and thalassemia:

- Collectively they’re categorized under hemolytic anemias.

- They’re different clinically and pathophysiologically, however these two look very similar radiographically.

- Signs and symptoms they look the same, but if we’ve got a patient that is African American then we’re talking about sickle cell, while if he was from Greece for ex. then we’re talking about thalassemia.

- Radiograph appears as osteoporosis, with hair on end appearance.

- Hair on end appearance: bone marrow is trying to produce more and more of primary blood cells, till it becomes hyperplastic, as a result it pushes the periosteum that lies over it upward, and once it’s elevated it starts laying bone underneath, that looks hairy on radiograph.

12- scleroderma:

- The only disease that causes generalized widening of all periodontal ligament spaces in the entire jaw is the scleroderma.

- The collagen metabolism is abnormal, so it gets thicker and thicker everywhere around teeth.

The end

Lecture date: 18/10
Dr. Abeer Al-hadeedi
Done by Zaid M.Al-Zu’bi

Radiology Sheet #4 By Zaid Al-Zu'bi

Radiology Sheet #4 By Zaid Al-Zu'bi

Re: Radiology Sheet #4 By Zaid Al-Zu'bi