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Systemic Diseases Manifestedin the Jaws
C H A P T E R 25 Oral Radiology
P R I N C I P L E Sa n d I N T E R P R E T A T I O N Sixth Edition
White and pharoahSeyed vahid malek hosseini
Systemic Diseases Manifestedin the Jaws
• Disorders of the endocrine system, bone metabolism, and other systemic diseases may have an effect on the form and function of bone and teeth.
• Bone functions: support, protection, reserve of calcium for the body environment for hemopoiesis
• The effects of systemic diseases of bone are brought about by changes in the number and activity of osteoclasts, osteoblasts, and osteocytes.
Radiographic Features• 1. A change in size and shape of the bone• 2. A change in the number, size, and orientation of trabeculae• 3. Altered thickness and density of cortical structures• 4. An increase or decrease in overall bone density
Endocrine Disorders• HYPERPARATHYROIDISM
• PTH increases bone remodeling in preference of osteoclastic resorption, which mobilizes calcium from the skeleton • Women are two to three times more commonly affected than men• 30 to 60 years of age.
Clinical manifestations• renal calculi, peptic ulcers, psychiatric problems, or bone and joint
pain.• All related to hypercalcemia.• Gradual loosening, drifting, and loss of teeth may occur.
Radiographic Features
• Only about one in fi ve patients with hyperparathyroidism has radiographically observable bone changes• 1. The earliest and most reliable changes of hyperparathyroidism are
subtle erosions of bone from the subperiosteal surfaces of the phalanges of the hands.• 2. Demineralization of the skeleton results in an unusual radiolucent
appearance.• 3. Osteitis fibrosa cystica are localized regions of bone loss produced by
osteoclastic activity resulting in a loss of all apparent bone structure.
• 4. Brown tumors occur late in the disease and in about 10% of cases. These peripheral or central tumors of bone are radiolucent. The gross specimen has a brown or reddish-brown color.• 5. Pathologic calcifications in soft tissues have a punctate or
nodular appearance and occur in the kidneys and joints• 6. In prominent hyperparathyroidism, the entire calvarium
has a granular appearance caused by the loss of central (diploic) trabeculae and thinning of the cortical tables
Radiographic Features of the Jaws.• Demineralization and thinning of cortical boundaries :jaws cortical
inferior border, mandibular canal, and the maxillary sinuses• radiolucent appearance that contrasts with the density of the teeth• change in the normal trabecular pattern = ground-glass• Brown tumors in facial bones and jaws
Brown tumors• May be Multiple within a single bone• defined margins• May produce cortical expansion• If solitary, the tumor may resemble a central giant cell granuloma or
an aneurysmal bone cyst
Radiographic Features of the Teeth and AssociatedStructures
• loss of the lamina dura that may give the root a tapered appearance because of loss of image contrast.
loss of bone and lamina dura andthe granular texture of the bone
subperiosteal erosion in hyperparathyroidism
Hyperparathyroidism
HYPOPARATHYROIDISM ANDPSEUDOHYPOPARATHYROIDISM• Produce hypocalcemia• Radiographic examination of the jaws may reveal dental enamel
hypoplasia, external root resorption, delayed eruption, or root dilacerations• • On skull radiographs this calcification appears flocculent and paired
within the cerebral hemispheres on the posteroanterior view
• Radiographic examination of the jaws may reveal dental enamel hypoplasia, external root resorption, delayed eruption, or root dilacerations
dental anomalies
HYPERPITUITARISMAcromegaly and giantism• increases the production of growth hormone• causes overgrowth of all tissues in the body
• excessive growth of the mandible• enlargement of the sella turcica• enlargement of the paranasal sinuses (especially the frontal sinus)• diffuse thickening of the outer table of the skull
Radiographic Features of the Jaws• enlargement of the jaws, most notably the mandible• The increase in the length of the dental arches results in spacing of
the teeth• angle between the ramus and body of the mandible may increase• combination with enlargement of the tongue (macroglossia), may
result in anterior flaring of the teeth and the development of an anterior open bite• the most profound growth occurs in the condyle and ramus, often
resulting in a class III skeletal• The thickness and height of the alveolar processes may also increase
Radiographic Changes Associated with the Teeth• The tooth crowns are usually normal in size, although the roots of
posterior teeth often enlarge as a result of hypercementosis.• Supereruption of the posterior teeth may occur in an attempt to
compensate for the growth of the mandible.
HYPOPITUITARISM• Result in dwarfism• failure of development of the maxilla and the mandible• Eruption of the primary dentition occurs at the normal time, but
exfoliation is delayed by several years• The crowns of the permanent teeth form normally, but their eruption
is delayed several years• The third molar buds may be completely absent• The jaws, especially the mandible, are small, which results in
crowding and malocclusion
HYPERTHYROIDISMThyrotoxicosis and Graves ’ disease• advanced rate of dental developmentand early eruption, with
premature loss of the primary teeth• Adults may show a generalized decrease in bone density or loss of
some areas of edentulous alveolar bone.
HYPOTHYROIDISMMyxedema and cretinism• The base of the skull shows delayed ossifi cation, andthe paranasal
sinuses only partially pneumatize. Dental development is delayed, and the primary teeth are slow to exfoliate.• in children include delayed closing of the epiphyses and skull sutures ,
production of numerous wormian bones (accessory bones in the sutures).• Effects on the teeth include delayed eruption, short roots, and thinning of
the lamina dura. The maxilla and mandible are relatively small. Patients with adult hypothyroidism may show periodontal disease, loss of teeth, separation of teeth as a result of enlargement of the tongue, and external root resorption.
DIABETES MELLITUS• no characteristic radiographic features
• Periodontal disease associated with diabetes is radiographically indistinguishable
CUSHING ’ S SYNDROME• excess of secretion of glucocorticoids
•Radiographic Features• generalized osteoporosis can result in pathologic fractures• granular bone pattern• skull can show thinning and mottled appearance• Teeth erupt prematurely• partial loss of the lamina dura
Cushing ’ s syndrome manifested in the jaws as thinningof the lamina dura
Metabolic Bone Diseases 461
OSTEOPOROSIS• generalized decrease in bone mass• changes in trabecular architecture, the volume of trabecular bone,
and the size and thickness of individual trabeculae.• occurs with the aging• The most important clinical manifestation of osteoporosis is fracture• distal radius, proximal femur, ribs, vertebrae
Radiographic Features• overall reduction in the density of bone• Reduced density and thinning of inferior mandibular cortex• Reduction in the number of trabeculae• lamina dura appear thinner
Osteoporosis evident as a loss of the normal thickness anddensity of the inferior cortex of the mandible.
RICKETS AND OSTEOMALACIA• inadequate serum and extracellular levels of calcium and phosphate• rickets is usually applied when the disease affects the growing• term osteomalacia is used when this disease affects the mature
skeleton in adults
Radiographic Features• widening and fraying of the epiphyses of the long bones• The soft weight-bearing bones such as the femur and tibia undergo a
characteristic bowing.• Greenstick fractures
Radiographic Features of the Jaws• jaw cortical structures such as the inferior mandibular border or the
walls of the mandibular canal may thin.• the trabeculae become reduced in density, number, and thickness• In severe cases, the jaws appear so radiolucent that the teeth appear
to be bereft of bony support.• an overall radiolucent appearance and sparse trabeculae.
Radiographic Changes Associated with the Teeth• Rickets• In infants and childhood may result in hypoplasia of developing dental
enamel• retarded tooth eruption• The lamina dura and the cortical boundary of tooth follicles may be
thin or missing.• Osteomalacia• does not alter the teeth• The lamina dura may be especially thin
Rickets may cause thinning (hypoplasia) or decreased mineralization(hypocalcification) of the enamel as seen in this bitewing view
HYPOPHOSPHATASIA• low level of serum alkaline phosphatase• Radiographic Features• generalized radiolucency of the mandible and maxilla• The cortical bone and lamina dura are thin alveolar bone is poorly
calcified• primary and permanent teeth have a thin enamel• Teeth• a thin enamel layer and large pulp chambers and root canals• may be hypoplastic and may be lost prematurely
large pulp chambers in the deciduous dentitionand the premature loss of the mandibular incisors
RENAL OSTEODYSTROPHYrenal rikets• bone changes result from chronic renal failure• Hypocalcemia as a result of impaired calcium absorption• Hyperphosphatemia resulting from reduction in renal phosphorus
excretion.
Radiographic Features• density of the mandible and maxilla may be less than normal• decrease or an increase in the number of internal trabeculae• The cortical boundaries may be thinner or less apparent. • Hypoplasia & hypocalcification of the teeth• lamina dura may be absent or less apparent in instances of bone
sclerosis
areas of radiolucencycorresponding to loss of bone mass, loss ofdistinct lamina dura, and a sclerotic bone patternaround the roots of the teeth
diffuse sclerotic (radiopaque) bonepattern throughout the jaws. Note the loss of adistinct inferior cortex of the mandible resultingfrom an increase in the radiopacity of the internalaspect of the bone.
HYPOPHOSPHATEMIAVitamin D – resistant rickets and hypophosphatemic rickets
• conditions that produce renal tubular disorders resulting in excessive loss of phosphorus.
Radiographic Features• extreme cases are remarkably radiolucent.• thin enamel caps and large pulp chambers and root canals• periapical and periodontal abscesses occur• Periapical rarefying osteitis• defects in the formation of dentin• patient has premature loss of the teeth.• lamina dura may become sparse• cortical boundaries around• tooth crypts may be thin
radiolucent appearance of thejaws and hence the lack of bone density and the large pulp chambers
bone loss around the teeth, a granularbone pattern, large pulp chambers, and external root resorption.
OSTEOPETROSISAlbers-Schönberg and marble bone disease• defect in the differentiation and function of osteoclasts• Radiographic Features• increased radiopacity• any internal structure and even the roots of the teeth may not be
apparent• delayed eruption, early tooth loss, missing teeth,• malformed roots and crowns, and teeth that are poorly calcified and
dense calcification of all the bones.
increased density of the jaws, lack of eruption of the mandibular second bicuspids, narrow inferior alveolar nerve canal, and development of osteomyelitis in the body of the left mandible with periostitis
Other Systemic Diseases• PROGRESSIVE SYSTEMIC SCLEROSIS• a generalized connective tissue disease that cause collagen deposition• erosions at regions of muscle attachment• resorption is typically bilateral and fairly symmetric. Most of these
erosive borders are smooth and sharply defined. This resorption may be progressive with the disease.
an unusual pattern of mandibular erosions atregions of muscle attachment such as the angles, coronoid process, digastric region, or condyles
Radiographic Changes Associated with the Teeth• increase in the width of the periodontal ligament (PDL) spaces around
the teeth at least twice as thick as normal. • The lamina dura remains normal.
widening of the periodontalmembrane space around some of the teeth.
SICKLE CELL ANEMIA• The thinning of individual cancellous trabeculae and cortices is most
common in the vertebral bodies, long bones, skull, and jaws.• The skull may have widening of the diploic space and thinning of the
inner and outer tables• the outer table of the skull will not be apparent and a hair-on-end
appearance may occur• Osteomyelitis infections due to hypovascularity.
Radiographic Features of the Jaws• general osteoporosis• bone marrow hyperplasia may cause enlargement and protrusion of
the maxillary alveolar ridge
thickened diploic space and thinning of the skull cortex right=normal
hair-on-end bone pattern
THALASSEMIA• General Radiographic Features• Similar to sickle cell anemia, the radiographic features of thalassemia
generally result from hyperplasia of the ineffective bone marrow
• Theskull shows a generalized granular appearance
Radiographic Appearance of the Jaws.• Severe bone marrow hyperplasia prevents pneumatization of the
paranasal sinuses, especially the maxillary sinus, and causes an expansion of the maxilla that results in malocclusion.
granular appearance ofthe skull and thickening of the diploic space
thickened diploic space and that there is hint linear orientation of the trabeculae,especially in the frontal bone
thickened body of the mandibleand the sparse trabeculae and lack of maxillary antra
thick trabeculae and large bone marrow spaces