Uncommon

Transcript Uncommon

Radiologic Signs for Maxillofacial Diagnosis

Warning This web-based publication is provided solely for the immediate study needs of students enrolled at the University of Louisville for the course directed by Dr. Allan G. Farman.

All rights reserved. No part of this publication may be reproduced, stored in a retrieval system, or transmitted, in any form or by any means, electronic, mechanical, printed, photocopying, recording or otherwise without the written permission of the author. This material is derived from ISBN 0-8016-1549-6, for which legally recorded copyright is held by Drs. Allan G. Farman, Christoffel J. Nortjé and Robert E.Wood.

Acknowledgment

The assistance in scanning of these images by Ms. Nancy L. Hunter is recognized with thanks.

Dental Signs

Dental signs

• • • • • • •

Number of teeth Tooth size Tooth morphology Tooth structure Tooth eruption pattern Tooth position Regressive changes

Large Teeth

•

SINGLE

• Macrodontia • Connation • Fusion • Gemination • Single central incisor short stature syndrome •

MULTIPLE

• Normal variant • Adjacent to benign vascular, lymphatic or neural tumor • Lipomatosis • Unilateral hyperplasia • Pituitary giantism

Small Teeth

•

SINGLE

•

MULTIPLE

Small Teeth

•

SINGLE

• Microdontia (e.g. peg lateral) • Supernumerary teeth •

MULTIPLE

• Normal variant • Dentinogenesis imperfecta • Trisomy 21 • Facial hypoplasia • Pituitary dwarfism • Vascular tumors

Single/Few Teeth of Altered Form

(Common)

• Turner’s tooth (acquired enamel hypoplasia) • Dilaceration • Taurodontism • Enamel invaginations (dens in dente) • Peg lateral incisors • Enlarged cingulum • Enamel evaginations (Leung’s premolar) • Shovel-shaped incisors

Single/Few Teeth of Altered Form

(Uncommon)

• Connation (fusion and gemination) • Concrescence • Twinning • Tuberculated maxillary lateral/talon cusp • Hutchinson’s teeth and mulberry molars (congenital syphilis) • Premolarization of canines and molarization of premolars

Single/Few Teeth of Altered Form

(Rare)

• Secondary to mutilating surgery • Secondary to radiation therapy • Secondary to chemotherapy

Hypercementosis

• Physiologic with passive eruption • Idiopathic • Periodontal disease • Paget’s disease of bone • Acromegaly • Benign tumor (cementoblastoma) • Apparent in periapical cemental dysplasia

Hypodontia/Oligodontia

(common)

• Previously extracted teeth • Idiopathic • Ectodermal dysplasias • Previous radiation therapy • Trisomy 21 (Down’s syndrome)

Hypodontia/Oligodontia

(uncommon)

• Chondroectodermal dysplasia • Facial hypoplasia • Incontinentia pigmentii • Oral-facial-digital (Möhr’s) syndrome • Oculodento-osseous dysplasia • Oculomandibulodyscephaly syndrome (Hallerman-Streiff)

/continued

Hypodontia/Oligodontia

(uncommon)

• Oligodontia and primary mesodermal iris dysgenesis (Rieger’s syndrome) • PHC syndrome (Böök’s syndrome) • Craniofacial dysostosis (Crouzon’s Sx) • Ehlers-Danlos syndrome • Focal dermal hypoplasia syndrome (Goltz syndrome)

/continued

Hypodontia/Oligodontia

(uncommon)

• Pyknodysostosis • Progeria (Hutchinson-Gilford syndrome) • Hypoparathyroidism • Inverted Marfan’s syndrome

Hyperodontia/Supernumeraries

(common)

• Idiopathic • Cleft palate • Compound odontoma • Cleidocranial dysplasia

Hyperodontia/Supernumeraries

(uncommon)

• Osteomatosis intestinal polyposis syndrome (Gardner’s syndrome) • Oculomandibulodyscephaly syndrome (Hallerman-Streiff syndrome) • Oral-facial-digital syndrome • Distomus • Achondroplasia • Ehlers-Danlos syndrome

Natal teeth

• Normal variant • Chondro-ectodermal dysplasia (Ellis van Crevald syndrome)

Single Failure in Eruption

Failure in eruption - single

(common)

• Idiopathic • Supernumerary teeth • Hypodontia (non-development of tooth) • Mechanical obstruction by other tooth • Retained primary tooth or tooth root • Dentigerous and eruption cysts

/continued

Failure in eruption - single

(common)

• Benign tumor (e.g. odontoma, ameloblastic fibroma, ameloblastic fibro-odontoma, adenomatoid odontogenic tumor) • Odontogenic keratocyst • Cleft palate • Ankylosis and submersion • Inflammation coronal to erupting tooth • Overlying tooth with pulpotomy

Failure in eruption - single

(uncommon)

• Odontogenic myxoma • Cherubism • Unicystic ameloblastoma • Langerhans’ cell disease • Ossifying fibroma • Malignancy and radiation therapy • Fibrous dysplasia • Post-extraction scar

Failure in eruption - multiple

(common)

• Fibromatosis gingivae • Drug-induced gingival hyperplasia • Cleidocranial dysplasia • Condylar hypoplasia and ankylosis • Cherubism

Failure in eruption - multiple

(uncommon)

• Osteomatosis intestinal polyposis syndrome (Gardner’s syndrome) • Acrocephalysyndactyly (Apert’s syndrome) • Gingival hyperplasia syndromes • Chondroectodermal dysplasia Ellis-van Crevald syndrome) • Trisomy 21

/continued

Failure in eruption - multiple

(uncommon)

• Focal dermal hypoplasia (Goltz syndrome) • Osteopetrosis • Regional odontodysplasia • Progeria ( Hutchinson-Gilford syndrome) • Pseudohypoparathyroidism • Pyknodysostosis • Juvenile hypothyroidism (cretinism) • Ectodermal dysplasias • Vitamin D deficiency syndromes

Premature Eruption

(common)

• Normal variant • Early loss of primary teeth

Premature Eruption

(uncommon)

• Adjacent benign vascular or neural tumor • Underlying malignant tumor • Underlying osteomyelitis • Hyperthyroidism • Pituitary giantism • Previous radiation therapy • Hypergonadism • Cushing’s syndrome • Adrenogenital syndrome

Early Tooth Loss

(common)

• Rampant dental caries • Dentofacial trauma • Juvenile periodontosis/periodontitis

Early Tooth Loss

(uncommon)

• Langerhans’ cell disease • Factitial injury • Cyclic neutropenia • Malignancy (leukemia, lymphoma, neuroblastoma, rhabdomyosarcoma) • Hyper keratosis palmoplantaris and periodontoclasia in childhood (Papillon Lefeuvre syndrome)

/continued

Early Tooth Loss

(uncommon)

• Radicular dentin dysplasia • Acrodynia (pink disease) • Other heavy metal poisoning • Acatalasia • Hyperparathyroidism

Early Tooth Loss

(rare)

• Acro-osteolysis • Severe Rickets • Pituitary cachexia syndrome (Simmond’s syndrome) • Chediak-Higashi syndrome

Displaced Teeth/Tooth Buds

(common)

• Normal variant • Malocclusion • Impaction • Dentigerous cysts • Other cysts • Traumatic displacement • Submergence

Displaced Teeth/Tooth Buds

(uncommon)

• Cherubism • Lateral inflammatory odontogenic cyst of the mandible (Stoneman’s cyst) • Benign giant cell tumor • Ameloblastoma and ameloblastic odontoma • Melanotic neuro-ectodermal tumor of infancy

/continued

Displaced Teeth/Tooth Buds

(uncommon)

• Other benign tumors • Osteomyelitis including osteomyelitis of the maxilla in the newborn • Langerhans’ cell disease • Malignant tumors (e.g. Burkitt’s lymphoma, lymphosarcoma, neuroblastoma, rhabdomyosarcoma)

Coronal Radiolucency in Tooth

(common)

• Dental caries • Radiolucent resin restorations • Cervical burnout and Mach phenomenon • Proximal overlap artifact • Enamel hypoplasia • Abrasion, attrition and erosion • Dens in dente

Coronal Radiolucency in Tooth

(common)

• Dental caries • Radiolucent resin restorations • Cervical burnout and Mach phenomenon • Proximal overlap artifact • Enamel hypoplasia • Abrasion, attrition and erosion • Dens in dente

Coronal Radiolucency in Tooth

(uncommon)

• Idiopathic internal resorption • External resorption • Radiation caries • Pulpal diverticula • Leung’s premolar (evagination of pulp) • Radiolucent internal enameloma

Enlarged dental pulp

(common)

• Rotation of anterior teeth • Developing teeth • Normal variant (large cornua) • Taurodontism • Internal resorption • Macrodontia • Connation (fusion and gemination)

Enlarged dental pulp

(uncommon)

• Enamel evagination (Leung’s premolar) • Vitamin D resistant Rickets • Shell teeth of Rushton • Hypophosphatasia • Renal osteodystrophy • Pulpal extension into enamel pearl

Small dental pulp

(common)

• Normal variant • Teeth in elderly (secondary dentin) • Reactive to dentin caries • Traumatically induced • Dentinogenesis imperfecta

Small dental pulp

(uncommon)

• Osteogenisis imperfecta • Dentin dysplasias

Dental Enamel Aberrations

(common)

• Dental caries • Environmental enamel hypoplasia (Turner’s tooth; neonatal disease; exanthematous fevers; nutritional deficiency; metabolic disease; drug induced; fluorosis) • Amelogenesis imperfectas

Dental Enamel Aberrations

(uncommon)

• Mucopolysacchaidoses IV (Morquio Brailsford syndrome) • Ehlers-Danlos syndrome • Hypophosphatasia • Hypoparathyroidism • Radiation therapy during tooth development

Dentin Aberrations

(common)

• Dental caries • Idiopathic internal resorption • Dentinogenesis imperfecta • Regional odontodysplasia

Dentin Aberrations

(uncommon)

• Osteogenesis imperfecta • Dentin dysplasias • Shell teeth of Rushton • Ehlers-Danlos syndrome • Radiation therapy during tooth development

Persistent Open Root Apex

• Normal variation • Post-dentition supernumerary tooth • Non-vital tooth • Periapical pathosis (cyst; granuloma; abscess) • Dens evaginatus (Leung’s premolar) • Idiopathic internal resorption

Prematurely Closed Root Apex

• Previous trauma to tooth • Radiation therapy during tooth development • Dentinogenesis imperfecta • Osteogenesis imperfecta • Radicular dentin dysplasia

Calcified pulp tissue

• Pulp stone • Normal variant for elderly • Projection artifact (molars) • Reaction to dentin caries or deep restoration • Subsequent to trauma • Calcareous degeneration • Superimposition of enamel pearl • Dentin dysplasias • Dentinogenesis imperfecta

Fractured Tooth Appearance

• True fractured tooth • Periodontal ligament shadow from adjacent tooth • Overlying lip, cheek or nose line • Bone trabecular pattern or nutrient canal • Accessory lateral pulp canal • Alveolar bone fracture • Radiographic artifact (film crimp; static, etc.)

External Root Resorption

(normal variants)

• Physiologic resorption (primary teeth) • Traumatic occlusion • Aberrant resorption of mesial root of lower first molar • Normal variant (pulpotomy of primary tooth) • Projection artifact (foreshortening) • Incomplete formation (tooth development)

External Root Resorption

(common pathologic)

• Apical pathosis (cyst; granuloma; abscess) • Iatrogenic - excessive orthodontic force • Idiopathic - uncertain cause • Re-implantation of avulsed tooth • Root canal therapy • Benign odontogenic cysts and tumors (especially dentigerous cyst, ameloblastoma and central giant cell granuloma)

External Root Resorption

(uncommon pathologic)

• Factitial injury • Inostosis • Malignant tumors (e.g. lymphoma) • Oxalosis • Hyperparathyroidism • Periodontal disease • Foreign body reaction • Idiopathic internal resorption

Internal Tooth Resorption

• Idiopathic • Trauma-induced • Caries-induced • Causes of enlarged pulps • Pulpal diverticuli • External resorption • Odontomalacia

Dental calculus and look-alikes

• True dental calculus • Restoration overhangs • Bony ledges adjacent teeth • Enamel pearl

Tooth-like Structures

(near oral cavity)

• Avulsed tooth or tooth fragment (trauma or iatrogenic) • Supernumerary teeth • Cleft palate associated • Compound odontoma • Distomus • Epignathus

Tooth-like Structures

(distant from oral cavity)

• Lithopedion • Ovarian teratoma • Other teratoma (e.g. intra-cranial)

Periodontal Signs

Radiologic Signs Concerning the Periodontium

• Loss of lamina dura (local) • Loss of lamina dura (general) • Accentuation of lamina dura • Widened periodontal ligament space • Ankylosis • Crestal lucency leading to decreased alveolar bone

Localized Loss of Lamina Dura

(normal variations and confusing shadows)

• Apex of maxillary canine (canine fossa) • Tooth rotation • Maxillary premolars before maturation • Projection over maxillary sinus • Tongue out of roof of mouth during panoramic • Projection over mandibular canal • Projection over mental foramen

Localized Loss of Lamina Dura

(common pathlogic)

• Inflammatory periapical pathosis (apical granuloma, cyst or abscess) • Simple (traumatic) bone cyst • Periapical cemental dysplasia • Focal osteomyelitis

Localized Loss of Lamina Dura

(uncommon pathlogic)

• Malignant tumor (e.g. osteogenic sarcoma) • Fibrous histiocytoma • Langerhans’ cell disease

Generalized Loss of Lamina Dura

(common pathlogic)

• Idiopathic • Osteoporosis • Paget’s disease of bone • Leukemia

Generalized Loss of Lamina Dura

(uncommon pathlogic)

• Metastatic malignancy (especially breast) • Hyperparathyroidism • Hypoparathyroidism • Multiple myeloma • Osteomalacia • Rickets (including vitamin D resistant form) • Cushing’s syndrome

/continued

Generalized Loss of Lamina Dura

(uncommon pathlogic)

• Renal acidosis • Acromegaly • Oxalosis • Hypervitaminosis D • Hypovitaminosis C • Scleroderma (systemic sclerosis) • Hyperphosphatasia • Burkitt’s lymphoma • Thalassemia

Accentuation of Lamina Dura

• Normal variant • Scleroderma (systemic sclerosis)

Widened PDL Space

(common)

• Projection effect • Normal finding around necks of teeth • Periodontal disease (furcation involvement) • Periapical inflammation • Traumatic occlusion • Dental trauma (avulsion or fractured root) • Jaw fracture through tooth socket • Root shadow cast over sinus • Scleroderma (systemic sclerosis)

Widened PDL Space

(uncommon)

• Re-implantation of avulsed tooth • Diabetes mellitus • Periodontosis • Osteomyelitis • Malignant tumors (especially osteogenic sarcoma) • Fibrous histiocytoma • Cystinosis • Actinomycotic infection

Suspision of Tooth Ankylosis

COMMON UNCOMMON

• True ankylosis of retained primary • Trauma • Re-implantation • Obscuring condensing osteitis • Infection • Inostosis • Socket sclerosis (false ankylosis) • Obscuring idiopathic osteosclerosis

Crestal Radiolucency

(common)

• Early destructive periodontal disease • Hyperemic decalcification • Juvenile periodontosis • Factitial injury • Acute necrotizing ulcerative gingivitis

Crestal Radiolucency

(uncommon)

• Langerhans’ cell disease • Hyperkeratosis palmoplantaris and periodontoclasia in children (Papillon Lefevre syndrome) • Leukemia • Local malignancy (central or peripheral) • Previous radiation therapy • Hypothuroidism (cretinism/myxedema)

/continued

Crestal Radiolucency

(uncommon)

• Hyperthyroidism • Hyperparathyroidism • Peripheral giant cell granuloma (epulis) • Other epulides • Cyclic neutropenia • Hypophosphatasia • Acrodynia

/continued

Crestal Radiolucency

(uncommon)

• Acro-osteolysis • Self-mutilative syndromes • Acatalasia • Pituitary cachexia (Simmond’s disease) • Chediak-Higashi syndrome

Jaw Structure

Fine Signs

Radiolucency

• Periapical radiolucency • Pericoronal radiolucency • Radiolucency lateral to tooth • Solitary radiolucency (well-defined) not necessarily associated with tooth • Solitary radiolucency with ragged borders • Radiolucency in maxillary lateral incisor region • Non-cyst-like radiolucency of bone

/continued

Radiolucency

• Rarefying osteitis • Blurring of trabecular pattern • Diminished number of trabeculae • Generalized rarefaction • Multilocular radiolucency • Ameloblastoma-like radiolunency • Radiolucency below mandibular canal • Expansile jaw lesions • Lesions\with undulating/crenulated margins

/continued

Radiolucency

• Lytic lesions with wide band-like borders • Widened mandibular canal • Scattered bone destruction separated by normal or near-normal bone • Short linear area of radiolucency in inferior cortex of mandible • Cyst-like radiolucency with window-like cortical breaching • Thinned mandibular lower cortex

/continued

Radiolucency

• Ballooned mandibular lower cortex • Attenuation of shadow of follicle wall • Discontinuity of antral or nasal wall • Suspected daughter cysts • External erosion of bone • Lesion with no internal structure • Multiple separate well-defined lucencies • Multiple osteolytic lesions with punched out margins

Radiopacity and Mixed Radiopacity/Radiolucency

• Periapical mixed lucent/opaque • Pericoronal mixed lucent/opaque • Periapical homogeneous radiopacities • Solitary mixed lucent/opaque lesion not necessarily contacting tooth • Mixed lucent/opaque lesion of TMJ • Sclerosing osteitis • Increased girth of individual trabeculae

/continued

Radiopacity and Mixed Radiopacity/Radiolucency

• Granular bone • Solitary opacity not contacting teeth • Compound odontoma • Complex odontoma • Opacity denser than normal bone • Multiple separate opacities • Root-like density in bone • Possible causes of root in bone appearance

/continued

Radiopacity and Mixed Radiopacity/Radiolucency

• Suspected foreign body (metallic or non metallic) • Sequestra-like density • Target lesion (radiopacity with peripheral shadow) • Excrescence with bone density • Thickened mandibular lower cortex • Laminar periosteal new bone

/continued

Radiopacity and Mixed Radiopacity/Radiolucency

• New periosteal bone with internal lysis • Sunray spiculation (new bone perpendicular to cortex) • Lesions with internal spindly trabeculae • Lesions with septae or pseudoseptae • Lesions with honeycombed internal structure • Lesions with wispy internal structure

/continued

Radiopacity and Mixed Radiopacity/Radiolucency

• Lesions with internal residual bone • Lesions with tubular internal structure • Lesions with internal rounded dense opacities • Linear striations (driven snow) within jawbone • Suspected osteoblastic metastases

Radiolucent Lesions

Periapical Radiolucency

(normal)

• Marrow space • Papillae of developing teeth • Maxillary sinus • Incisive foramen • Nasolacrimal canals • Submandibular fossa • Sublingual fossa • Mandibular canal and mental foramen

/continued

Periapical Radiolucency

(normal)

• Mental depression (chin) • Tomographic plane (including panoramic) artifact • Processing errors ( e.g. developer splash)

Periapical Radiolucency

(common pathologic)

• Periapical cyst, granuloma or abscess • Fibrous healing defect • Periapical cemental dysplasia (early) • Periodontal abscess

Periapical Radiolucency

(uncommon pathologic)

• Dentigerous cyst of underlying tooth • Traumatic (simple) bone cyst • Other cysts • Osteomyelitis • Underlying benign tumor (e.g. cementifying/ossifying fibroma) • Primary malignant tumor (e.g. leukemia)

/continued

Periapical Radiolucency

(uncommon pathologic)

• Central giant cell granuloma • Langerhans’ cell disease • Lingual salivary gland depression (Stafne’s bone cavity) • Multiple myeloma • Metastatic malignancy (especially breast)

/continued

Periapical Radiolucency

(uncommon pathologic)

• Early cementoblastoma or osteoblastoma • Radicular dentin dysplasia • Early odontomas

Pericoronal Radiolucency

(common)

• Normal dental follicle space • Dentigerous cyst • Envelopmental odontogenic keratocyst • Adenomatoid odontogenic tumor • Early odontoma or ameloblastic fibro-odontoma

Pericoronal Radiolucency

(uncommon single)

• Ameloblastic fibroma • Ameloblastoma • Early calcifying epithelial odontogenic tumor (Pindborg tumor) • Mucopolysaccharidoses (I-H) Hurler’s syndrome • Early calcifying odontogenic cyst

Pericoronal Radiolucency

(multiple)

• Dental follicle spaces • Multiple nevoid basal cell carcinoma syndrome (Gorlin and Goltz syndrome) • Osteomastosis- intestinal polyposis syndrome (Gardner’s syndrome) • Mucopolysaccharoidoses • Regional odontodysplasia

Radiolucency Lateral to Tooth

(common)

• Lateral periodontal abscess • Lateral periodontal cyst • Endodontic perforation • Extension of disease from adjacent tooth

Radiolucency Lateral to Tooth

(uncommon)

• Lateral canal periapical cyst • Odontogenic keratocyst • Neurofibroma or neurilemmoma • Giant cell granuloma • Unilocular ameloblastoma • Langerhans’ cell disease • Hyperparathyroidism

Well-defined solitary lucency not necessarily contacting teeth

(uncommon)

• Odontogenic keratocyst • Ameloblastoma • Giant cell granuloma • Early ossifying/cementifying fibroma • Early fibrous dysplasia • Eosinophilic granuloma

/continued

Well-defined solitary lucency not necessarily contacting teeth

(uncommon)

• Neurofibroma • Odontogenic myxoma • Central hemangioma

Well-defined solitary lucency not necessarily contacting teeth

(rare)

• Aneurysmal bone cyst • Chondrosarcoma • Central fibroma • Tuberculous osteomyelitis • Hydatid cyst • Early calcifying epithelial odontogenic tumor (Pindborg’s tumor)

Single Radiolucency with Ragged Borders

(common)

• Chronic osteitis • Osteomyelitis • Peripheral squamous cell carcinoma • Infected radicular, residual or other cyst

Single Radiolucency with Ragged Borders

(uncommon)

• Early fibrous dysplasia • Metastatic carcinoma • Malignant salivary gland tumor involving bone • Osteolytic osteosarcoma • Multiple myeloma • Chondrosarcoma

/continued

Single Radiolucency with Ragged Borders

(uncommon)

• Fibrosarcoma • Lymphosarcoma • Melanotic neuroectodermal tumor of infancy • Leukemia or Ewing’s sarcoma • Aneurysmal bone cyst • Neurofibroma • Odontogenic myxoma

Radiolucency in Region of Maxillary Lateral Incisor

(common)

• Incisive fossa/foramen • Canine fossa • Periapical cyst, granuloma or abscess • Rarefying osteitis from adjacent central • Other periapical radiolucencies

Radiolucency in Region of Maxillary Lateral Incisor

(uncommon)

• Clefts • Aberrant foramina in anterior maxilla • Nasopalatine duct cyst • Odontogenic keratocyst • Depression from nasolabial cyst • Post-surgical defect

Non-Cystlike Radiolucency of Bone

• Focal osteoporotic defect • Large marrow space • Normal variant of tuberosity • Sparse trabeculation in child • Maxillary sinus • Foramina • Submandibular fossa

/continued

Non-Cystlike Radiolucency of Bone

• Sublingual fossa • Post-coronoid depression • Sigmoid notch shadow • Acute osteomyelitis • Healing surgical defect • Decalcification secondary to overlying inflammation

Rarefying Osteitis - Focal Osteomyelitis

(common)

• Foramina or dental Papilla • Antrum or nasal passage • Mandibular canal or mental foramen • Large marrow space • Periodontal abscess • Apical cyst, granuloma or abscess • Early periosteal cemental dysplasia • Healing surgical defect

Rarefying Osteitis - Focal Osteomyelitis

(uncommon)

• Actinomycosis • Previous radiation therapy • Leukemia • Metastatic malignancy (especially breast) • Langerhans’ cell disease

Blurring of Trabecular Pattern

• Osteomyelitis • Decalcification secondary to inflamed adjacent tissues • Radiodontic pitfall (e.g. motion unsharpness; bend artifact)

Diminished Number of Trabeculae

(common)

• Normal variant in children • Inflammatory disease • Osteopenic metabolic diseases

(uncommon)

• Anaplastic anemias • Previous radiation therapy • Vitamin D deficiency syndrome • Thalassemia and Sickle cell anemia • Neurofibroma

Decreased Size of Trabeculae

(common)

• Normal variation • Infection and inflammation • Disuse atrophy of alveolus

(uncommon)

• Previous radiation therapy • Vitamin D deficiency syndrome • Thalassemia

Generalized Rarefaction

(common)

• Osteoporosis • Cortisone therapy • Rheumatoid arthritis • Prolonged immobilization • Malignant and other cachetic diseases

Generalized Rarefaction

(uncommon)

• Cushing’s syndrome • Hyperparathyroidism • Vitamin D deficiency syndrome • Acromegaly • Pancreatitis • Malnutrition • Pregnancy-related changes

/continued

Generalized Rarefaction

(uncommon)

• Diabetes mellitus • Scurvy • Inherited anemias • Leukemia • Langerhans’ cell disease • Multiple myeloma • Paget’s disease of bone • Osteogenesis imperfecta • Renal acidosis

Generalized Rarefaction

(rare)

• Hypophosphatasia • Hyperphosphatasia • Hypoparathyroidism • Thyrotoxicosis • Hypogonadism • Agranulocytosis • Oxalosis • Previous radiation therapy

Multilocular Radiolucency

(common unilateral)

• Aberrant normal anatomy (maxillary antrum) • Ameloblastoma • Odontogenic keratocyst • Central giant cell granuloma • Odontogenic myxoma • Multilocular radicular or residual cyst

Multilocular Radiolucency

(uncommon unilateral)

• Mucoepidermoid tumor • Aneurysmal bone cyst • Arterio-venous malformation • Central hemangioma • Ameloblastic fibroma • Calcifying odontogenic cyst • Early fibrous dysplasia • Developing odontoma • Langerhans’ cell disease

Multilocular Radiolucency

(rare unilateral)

• Calcifying epithelial odontogenic tumor (Pindborg tumor) • Central fibroma • Chondroma • Sporotrichosis • Cerebroside lipoidosis (Gaucher’s disease) • Oxalosis

Multilocular Radiolucency

(bilateral)

• Normal variation for maxillary sinuses • Cherubism • Cerebroside lipoidosis (Gaucher’s disease) • Multiple nevoid basal cell carcinoma syndrome (Gorlin and Goltz syndrome) • Oxalosis

Ameloblastoma-like Radiolucency - “Soap Bubble” Appearance

(common)

• Ameloblastoma • Odontogenic keratocyst • Giant cell granuloma • Multilocular large radicular or residual cyst

Ameloblastoma-like Radiolucency

(uncommon)

• Ameloblastic fibroma • Traumatic (simple) bone cyst • Langerhans’ cell disease • Ossifying fibroma • Fibrous dysplasia • Calcifying odontogenic cyst • Sporotrichosis • Oxalosis

Lucency Below Mandibular Canal

(common)

• Normal variation • Submandibular fossa • Lingual salivary gland defect (Stafne)

(uncommon)

• Eosinophilic granuloma • Benign tumor of salivary gland origin • Subperiosteal neurofibroma • Benign vascular tumor

Expansile Jaw Lesions

(common)

• Laminar periosteal new bone ( e.g. osteitis proliferans) • Ameloblastoma • Radicular or residual cyst • Central giant cell granuloma • Dentigerous cyst • Fibrous dysplasia • Cherubism

Expansile Jaw Lesions

(uncommon)

• Hemangioma • Neurfibroma • Osteosarcoma or lymphosarcoma • Ossifying fibroma • Aneurysmal bone cyst

(rare)

• Traumatic (simple) bone cyst • Burkitt’s lymphoma

Lesions with Crenulated (Undulating) Margins

• Ameloblastoma • Central giant cell granuloma • Odontogenic myxoma • Other benign tumors • Odontogenic keratocyst • Botyroid lateral periodontal cyst

Lytic Lesions with Wide Band-like Borders

(common) (uncommon)

• Infected cyst • Lateral inflammatory odontogenic cyst • Fibrous dysplasia • Giant cell tumor • Aneurysmal bone cyst • Ossifying fibroma

(rare)

• Osteoblastoma • Osteoid osteoma

Widened Mandibular Canal

(common) (uncommon)

• Normal variant • Neurilemmoma • Neurofibroma • Vascular tumor, hamartoma or malformation • Malignant tumor (primary, extension or metastasis) • Lymphoma

Scattered Bone Destruction Separated by Normal Bone

(common) (uncommon)

• Acute osteomyelitis • Multiple myeloma • Squamous cell carcinoma • Actinomycosis • Osteoradionecrosis • Metastatic carcinoma • Oxalosis • Tuberculous osteomyelitis

Short Linear Area of Radiolucency in Inferior Cortex

• Acute osteomyelitis • Squamous cell carcinoma extending into bone • Other local malignant destruction (e.g osteogenic sarcoma)

Cyst-like Radiolucency with Window-like Cortical Breaching

• Ameloblastoma • Large radicular or residual cyst • Odontogenic myxoma • Central giant cell granuloma • Neurofibroma

Thinned Lower Cortex (Mandible)

(common) (uncommon)

• Multiple myeloma • Rheumatoid arthritis • Diseases associated with generalized rarefaction • Langerhans’ cell disease • Hyperparathyroidism • Thalassemia • Sickle cell anemia

(rare)

• Hemifacial atrophy (Romberg disease) • Osteogenesis imperfacta

Ballooned Inferior Cortex

(common)

• Dentigerous cyst • Periostitis ossificans • Large radicular or residual cyst • Fibrous dysplasia • Cementifying/ossifying fibroma • Ameloblastoma • Odontogenic myxoma

Ballooned Inferior Cortex

(uncommon)

• Central giant cell granuloma • Neurofibroma (blister lesion) • Hyperparathyroidism (Brown tumor) • Hemangioma • Ameloblastic fibroma • Calcifying odontogenic cyst

Ballooned Inferior Cortex

(rare)

• Aneurysmal bone cyst • Burkitt’s lymphoma • Central fibroma • Calcifying epithelial odontogenic tumor (Pindborg tumor) • Osteogenic sarcoma

Attenuation of Shadow of Follicle Wall

(common)

• Localized infection of primary tooth • Eruption cyst • Acute osteomyelitis

Attenuation of Shadow of Follicle Wall

(uncommon)

• Vitamin D deficiency syndromes • Leukemia • Langerhans’ cell disease • Burkitt’s lymphoma • Lymphosarcoma • Hyperparathyroidism

Attenuation of Shadow of Follicle Wall

(rare)

• Melanotic neuroectodermal tumor of infancy • Rhabdomyosarcoma • Neuroblastoma

Discontinuity of Nasal or Antral Wall

(common) (uncommon)

• Apical inflammation • Projection artifact

(rare)

• Osteogenic sarcoma • Langerhans’ cell disease • Lymphosarcoma • Antral mucocele • Osteomyelitis • Odontogenic myxoma • Ameloblastoma • Invasive squamous cell carcinoma • Invasive salivary gland malignancy • Long-standing antritis • Previous surgery

Suspected Daughter “Cysts”

(common) (uncommon)

• Odontogenic keratocyst • Ameloblastoma • Mucoepidermoid tumor (central) • Central hemangioma • Botyroid lateral periodontal cyst

External Erosion of Bone

• Adjacent squamous cell carcinoma • Scleroderma (systemic sclerosis) • Cystic hygroma • Secondary to pulsatile vessel • Hodgkin’s disease • Eosinophilic granuloma • Adjacent malignant adjacent lymph node • Metastatic malignancy • Secondary to PVC poisoning • Idiopathic

Lesion with no Internal Structure

(common) (uncommon)

• Odontogenic cyst • Non-odontogenic cyst • Traumatic bone cyst • Ameloblastoma • Odontogenic myxoma • Hemangioma • Neurofibroma • Osteolytic osteogenic sarcoma • Ameloblastic fibroma • Early calcifying cyst or tumor

Multiple Separate Well Defined Radiolucencies

(common)

• Normal variation • Multiple periapical pathoses (cysts, granulomas or abscesses) • Multiple nevoid basal cell carcinoma syndrome (Gorlin and Goltz syndrome) • Early stages of periapical cemental dysplasia

Multiple Separate Well Defined Radiolucencies

(uncommon) (rare)

• Cherubism • Multiple myeloma • Metastatic carcinoma • Langerhans’ cell disease Lymphosarcoma • Leukemia • Ameloblastomas • Skip lesion of osteosarcoma • Niemann-Pick disease • Cerebroside lipoidosis (Gaucher’s disease) • Mucopolysaccharoidoses • Hyperparathyroidism

Multiple Osteolytic Lesions with Punched Out Margins

• Multiple Myeloma • Langerhans’ cell disease • Metastatic carcinoma • Hemangioma • Burkitt’s lymphoma

Radiopaque and Mixed Radiolucent/Radiopaque Lesions

Periapical Mixed Lucency/Opacity

(common) (uncommon)

• Dental crypt • Rarefying osteitis plus tooth root • Mixed rarefying sclerosing osteitis • Periapical cemental dysplasia • Foreign body (e.g. root canal filling material) • Cementifying/ ossifying fibroma • Cementoblastoma • Paget’s disease of bone • Complex odontoma • Compound odontoma • Calcifying odontogenic cyst

Pericoronal Mixed Lucency/Opacity

(common) (uncommon)

• Complex odontoma • Compound odontoma • Adenomatoid odontogenic tumor • Ameloblastic fibro odontoma • Calcifying odontogenic cyst • Odontogenic fibroma • Cystic odontoma • Calcifying epithelial odontogenic tumor (Pindborg tumor)

Periapical Radiopacity

(common)

• Anatomic superimpositions • Tori and exostoses • Retained roots or unerupted tooth • Radiographic artifact • Sclerosing osteitis • Mature periapical cemental dysplasia • Hypercementosis • Foreign body

Periapical Radiopacity

(uncommon)

• Superimposed soft tissue calcification • Cementoblastoma • Osteoblastoma • Cementifying/ossifying fibroma • Mature complex odontoma • Osteoblastic metastases • Paget’s disease of bone

Single Mixed Lucency/Opacity Not Necessarily Contacting Tooth

(common)

• Dense bone island/osteosclerosis • Sclerosing/condensing osteitis • Osseous excrescence • Fibrous dysplasia • Periapical cemental dysplasia • Healing surgical defect • Developing odontomas • Cementifying/ossifying fibroma

Single Mixed Lucency/Opacity Not Necessarily Contacting Tooth

(uncommon)

• Chronic osteomyelitis • Paget’s disease of bone • Ameloblastic fibro-odontoma • Complex odontoma • Compound odontoma • Calcifying odontogenic cyst • Superimposed soft tissue calcification

Single Mixed Lucency/Opacity Not Necessarily Contacting Tooth

(rare)

• Osteoblastoma • Osteoid osteoma • Osteogenic sarcoma • Chondrosarcoma • Osteoblastic metastases

Mixed Lucency/Opacity in Region of Mandibular Condyle Head

• Osteochondroma • Chondrometaplasia • Osteomyelitis from middle ear • Healing traumatic injury to TMJ • Fibrous dysplasia • Ossifying fibroma • Osteoblastoma • Osteogenic sarcoma or Chondrosarcoma • Charcot’s joint

Simulating Sclerosing Osteitis

(common)

• Normal variation of trabeculation • Superimposed normal structure or tori • Focal sclerosing osteomyelitis (condensing osteitis) • Florid osseous dysplasia or periapical cemental dysplasia (late stage) • Fibrous dysplasia • Paget’s disease of bone • Iatrogenic (orthodontic treatrment)

Simulating Sclerosing Osteitis

(uncommon)

• Superimposed osteoma • Secondary hyperparathyroidism • Idiopathic hypercalcemia • Superimposed submandibular gland stone (sialolithiasis)

Simulating Sclerosing Osteitis

(rare)

• Osteopetrosis • Infantile cortical hyperostosis • Osteoradionecrosis • Osteogenic sarcoma • Osteoblastic metastases • Osteoblastoma and osteoid osteitis • Melorrheostosis • Myelosclerosis • Healing syphilitic gumma

Increased Girth of Individual Trabeculae

(common) (uncommon)

• Condensing osteitis (focal sclerosing osteomyelitis) • Central hemangioma • Neurofibroma • Fluorosis • Myelosclerosis • Osteoblastic metastases

Granular Bone

(common) (uncommon)

• Fibrous dysplasia • Osteomyelitis (bone replacing sequestrum) • Post-surgical defect • Paget’s disease of bone • Thalassemia • Cementifying/ossifying fibroma • Osteogenic sarcoma • Chondrosarcoma • Hodgkin’s disease • Renal osteodystrophy recovery phase • Groundou

Granular Bone

Solitary Opacity Not Necessarily Contacting Tooth

(common)

• Anatomic superimposition • Radiodontic pitfall (fixer splash) • Osteosclerosis, exostosis or torus • Unerupted tooth or retained root • Sclerosing osteitis or socket sclerosis • Benign cemental mass • Odontoma • Foreign body

Solitary Opacity Not Necessarily Contacting Tooth

(uncommon)

• Cementifying/ossifying fibroma • Compact osteoma • Osteogenic sarcoma • Chondrosarcoma • Osteoblastoma • Osteoid osteoma • Superimposed soft tissue calcification

Simulating Compound Odontoma

(common) (uncommon)

• Compound odontoma • Supernumerary teeth • Complex odontoma • Adenomatoid odontogenic tumor • Ameloblastic fibro odontoma • Ameloblastic odontoma • Distomus • Teratoma • Epignathion

Simulating Complex Odontoma

(common) (uncommon)

• Complex odontoma • Periapical cemental dysplasia (late phase) • Florid osseous dysplasia • Compound odontoma • Condensing osteitis • Compact osteoma • Cementifying/ossifying fibroma • Osteogenic sarcoma • Osteochondroma • Ameloblastic odontoma • Fibrous dysplasia (late)

Opacity Denser than Normal Bone

(common) (uncommon)

• Foreign body (e.g. fragment of metallic restorative material) • Odontomas • Florid osseous dysplasia or periapical cemental dysplasia (late phase) • Focal sclerosing osteitis • Osteopetrosis • Fibrous dysplasia • Pyknodysostosis • Compact osteoma • Osteogenic sarcoma • Osteomastosis intestinal polyposis syndrome (Gardner Sx) • Occulodento-osseous dysplasia

Multiple Separate Radiopacities

(common) (uncommon)

• Tori and exostoses • Periapical cemental dysplasia • Florid osseous dysplasia • Multiple retained roots or impacted teeth • Multiple socket sclerosis • Osteosclerosis including condensing osteitis • Calcinosis cutis • Osteomatosis-intestinal polyposis (Gardner) syndrome • Enchondromatosis and hemongiomatosis (Maffuci syndrome) • Gigantiform cementoma • Overlying soft tissue calcification

Root-like Density in Bone

(common) (uncommon)

• Retained root • Dense bone island (osteosclerosis) • Coronoid superimposition • Root displaced in soft tissues/fascial plane • Socket sclerosis • Antrolith • Bony spicule in antrum • Pterygoid hamulus superimposition • Superimposed sialolith • Other soft tissue calcification • Osteochondroma

Causes of Root in Bone

• Secondary to carious destruction of tooth crown • Traumatic injury with tooth fracture • Iatrogenic (incomplete extraction) • Displacement of root into adjacent soft tissues or sinus (superimposition)

Suspected Metallic Foreign Body

(common) (uncommon)

• Amalgam fragment • Body jewelry • Other restoratives or dental instruments • Artifact (scratched cassettes, fixer splash, panoramic ghosts, etc.) • Needles • Shot-gun pellets • Leaded glass fragments • Paper in cassette • Metal fragment in path of primary beam

Suspected Non-Metallic Foreign Body

(common) (uncommon)

• Calcified acne • Carotid atherosclerosis • Sialolithiasis • Calcified lymph node • Tooth fragment • Osteosclerosis • Subclinical fibrous dysplasia • Cysticercosis • Phlebolith • Myositis ossificans

Sequestra-like density

(common) (uncommon)

• • Acute osteomyelitis • Chronic osteomyelitis • Osteoradionecrosis • Osteogenic sarcoma

Also see Single Large Opacities list

• Tuberculosis • Actinomycosis • Syphilis • Mercury poisoning • Phosphorus poisoning (“phossy” jaw)

Target Lesion (Radiopacity with Peripheral Shadow

(common) (uncommon)

• Retained primary root • Infection around retained tooth root • Sequestra • Periapical cemental dysplasia • Odontoma • Cementoblastoma • Cementifying/ossifying fibroma • Fibrous dysplasia

(rare)

• Brodie’s abscess • Osteoblastoma • Osteoid osteoma

Excrescence with Density of Bone

(common) (uncommon)

• Idiopathic • Tori and exostoses • Ossifying fibrous epulis • Osteochondroma •

Soft tissue calcifications

• Hyperostosis • Fibrous dysplasia • Osteomatosis-intestinal polyposis syndrome (Gardner/s syndrome) • Peripheral chondroma • Chondrosarcoma

Thickened Mandibular Inferior Cortex

• Sickle cell anemia • Secondary to osteomyelitis • Fluorosis • Phosphorus poisoning • Myelosclerosis • Sclerostosis • Rarely a variant of normal

Laminar Periosteal New Bone

(common)

• Osteomyelitis • Periostitis ossificans (Garrè’s osteomyelitis)

Laminar Periosteal New Bone

(uncommon)

• Infantile cortical hyperostosis • Lateral inflammatory odontogenic cyst of the mandible (Stoneman’s cyst) • Superficial surface injuries to face • Cervicofacial actinomycosis • Tuberculosis affecting jaw • Syphilitic periostitis • Eosinophilic granuloma

/continued

Laminar Periosteal New Bone

(uncommon)

• Hypervitaminosis A or Scurvy • Leukemia (single new layer) • Osteogenic sarcoma • Ewing’s sarcoma • Neostosis secondary to hemodialysis • Idiopathic periostitis with dysproteinemia (Goldbloom’s syndrome) • Diffuse idiopathic skeletal hyperostoses Sx

New Periosteal Bone with Internal Destruction

• Chronic osteomyelitis • Tuberculous osteomyelitis • Osteogenic sarcoma

New Bone Perpendicular to Original Cortex

(common) (uncommon)

• Sickle cell anemia • Osteogenic sarcoma • Chondrosarcoma • Osteoblastic metastases • Reticulum cell sarcoma • Neuroblastoma • Thalassemia • Spherocytosis • Ewing’s sarcoma • Burkitt’s lymphoa • Syphilitic periostitis • Meningioma • Hemangioma • Ossifying fibrous epulis • Osteoma

Lesions with Internal Spindly Trabeculae

• Odontogenic myxoma • Central hemangioma • Central giant cell granuloma (unusual) • Ameloblastoma (unusual)

Lesions with Septae or Pseudo Septae

(common) (uncommon)

• Ameloblastoma • Central giant cell granuloma • Odontogenic myxoma • Odontogenic keratocyst • Traumatic (simple) bone cyst • Cherubism • Central hemangioma • Fibrous dysplasia • Chondroma

Lesions with Honeycombed Internal Structure

(common) (uncommon)

• Odontogenic myxoma • Central hemangioma • Ewing’s sarcoma • Aneurysmal bone cyst • Ameloblastoma • Central giant cell granuloma • Neurofibroma • Fibrous dysplasia • Osteogenic sarcoma

Lesions with Wispy Internal Structure

• Odontogenic myxoma • Central giant cell granuloma • Fibrous dysplasia • Neurofibroma

Lesions with Internal Residual Bone

(common) (uncommon)

• Odontogenic myxoma • Ameloblastoma • Central hemangioma • Invasive squamous cell carcinoma • Fibrous dysplasia • Ossifying fibroma • Osteochondroma • Hodgkin’s disease • Lymphoma

Lesions with Tubular Internal Structure

(common) (uncommon)

• Normal vascular channels (nutrient canals) • Central hemangioma • Arteriovenous malformation • Sturge-Weber syndrome (tram track calcifications in brain) • Central giant cell granuloma • Ameloblastoma • Neurofibroma

Lesions with Internal Rounded Dense Radiopacities

(common) (uncommon)

• Odontomas • Periapical cemental dysplasia • Florid osseous dysplasia • Adenomatoid odontogenic tumor • Paget’s disease of bone • Fibrous dysplasia • Osteogenic sarcoma • Chondrosarcoma • Chondrometaplasia

Linear Striations within Jawbone

• Normal variant (infant mandible) • Paget’s disease of bone (driven snow appearance) • Craniometaphyseal dysplasia (Pyle’s disease)

Suspected Osteoblastic Metastases

(common) (uncommon)

• Breast • Prostate • Liver • Lung • Rectum and colon • Neuroblastoma • Osteogenic sarcoma • Leiomyosarcoma • Hodgkin’s disease

Jaw Structure

Gross Changes

Gross Structural Changes

• Prognathism or retrognathia • Micrognathia • Unilateral small jaw • Enlargement of part of jaw • Obtuse or aberrant gonial angle • Persistent mandibular midline suture • Absent coronoid(s) • Deviation of chin • Deformed mandible

/continued

Gross Structural Changes

• Increased vertical depth of mandible • Unilateral or bilateral absence of condyle • Condylar hyperplasia • Suspected jaw fracture(s) • Pathologic fracture • Suspected hyoid fractures • Radiolucency in condylar neck/head • True and false TMJ ankylosis • Increased or decreased TMJ space

/continued

Gross Structural Changes

• Limited or increased TMJ movement • Small or enlarged antrum • Suspected antral foreign body • Antral opacification with normal walls • Antral opacification with abnormal walls • Antral opacification with breached cortices • Absent nasal bones • Depressed nasal bridge • Hypoplasia of maxilla and zygomas • Clefts

Prognathism

(common)

• Normal variation • Racial variance (Scandinavian and African) • Edentulous mandible (apparent) • Relative prognathism (e.g. retrognathic midface secondary to cleft) • Acromegaly

Prognathism

(uncommon)

• Paget’s disease of bone • Pituitary giantism • Hemifacial hyperplasia • Lymphangioma of tongue or cystic hygroma

Prognathism

(rare)

• Multiple nevoid multiple basal cell carcinoma syndrome (Gorlin and Goltz syndrome) • Craniometaphyseal dysplasia (Pyle’s disease) • Beckwith-Wiedemann syndrome • XXXXY syndrome • Waardenburg syndrome

Retrognathism

(common) (uncommon)

• Normal variant • Relative to protrusion of midface • TMJ ankylosis • Juvenile rheumatoid arthritis • Hemifacial hypoplasia • Subluxation in infancy • Hypopituitarism • Progressive hemiatrophy • Agenesis/dysgenesis of mandible • • Agnathia

Micrognathia-related

Micrognathia

(common) (uncommon)

• Mandibulofacial dysostosis (Treacher Collins syndrome) • Gonadal dysgenesis (Turner’s syndrome) • Juvenile rheumatoid arthritis (Still’s Sx) • Cleft lip, micrognathia and glossoptosis (Pierre Robin syndrome) • Oculoauricularvertebral dysplasia (Goldenhar’s Sx) • XX and XY Turner phenotype syndrome (Noonan’s syndrome) • Oculomandibulodyscephaly (Hallerman-Streiff Sx) • Pyknodysostosis

Micrognathia

(rare)

• Bird-headed dwarfism • Congenital telangiectatic erythema with growth retardation (Bloom’s syndrome) • 5P - (cric du chat) syndrome • Chondrodysplasia punctata (Conradi Hünermann syndrome) • De Lange’s syndrome • Diastrophic dwarfism

/continued

Micrognathia

(rare)

• G syndrome • Cleft palate, flattened facies and multiple congenital dislocations (Larsen’s Sx) • Long arm 21 deletion syndrome • Mesomelic dwarfism • Orofacial digital syndrome • Osteodysplasia • Progeria (Hutchinson-Gilford syndrome)

/continued

Micrognathia

(rare)

• Rubinstein-Taybi syndrome • Russell-Silver syndrome • Short arm deletion 18 syndrome • Smith-Lemli-Opitz syndrome • Thrombocytopenia-absent radius syndrome • Trisomy 13 syndrome • Trisomy 18 syndrome

Unilateral Small Jaw

(common) (uncommon)

• Lateral facial dysplasia • Unilateral TMJ ankylosis • Forceps delivery trauma • Radiation therapy in infancy • Hemifacial hypoplasia • Hemifacial atrophy (Romberg’s disease) • Partial mandibular agenesis • Linear scleroderma

(rare)

• Central hemangioma • Neurofibroma

Enlargement of Part of Jaw (anatomically correct)

• Adjacent hemangioma • Adjacent neurofibroma • Fibrous dysplasia • Hemifacial hyperplasia • Paget’s disease of bone

Obtuse Gonial Angle

(common) (uncommon)

• Normal age change • Edentulous mandible • Condylar hyperplasia contralateral condyle • Trisomy 21 • Scleroderma (systemic sclerosis) • Mucopolysaccharidoses I-H (Hurler’s syndrome) • Craniometaphyseal dysplasia (Pyle’s disease) • Osteopetrosis • Hemifacial hypoplasia

Aberrant Gonial Angle

(common) (uncommon)

• Normal variant • TMJ ankylosis • Juvenile rheumatoid arthritis • Mandibulofacial dysostosis (Treacher Collins syndrome) • Scleroderma • Neurofibroma • Trisomy 21 • Marfan’s syndrome • Isolated anomaly

Persistent Mandibular Midline Suture

(common) (uncommon)

• Normal <6 months age • Cleidocranial dysplasia • Midline fracture • Mandibular midline cleft • Normal variant

Absent or Diminished Coronoids

(common) (uncommon)

• Previous surgery • Panoramic radiograph outside focal trough • Lateral facial dysplasia • Scleroderma (systemic sclerosis) • Radiation therapy in • childhood • Hemifacial atrophy (Romberg’s disease) • Local or metastatic malignancy related erosion • Agnathia • Agenesis

Deviation of Chin Towards Affected Side

(common) (uncommon)

• Normal variant • Malocclusion (cross bite) • Unilateral TMJ ankylosis • Condylar hypoplasia • Lateral facial dysplasia • Childhood or forceps fracture of condyle • Torticollis • Hemifacial atrophy (Romberg’s disease) • Congenital unilateral facial hypoplasia • Partial mandibular agenesis

Deviation of Chin Away From Affected Side

(common) (uncommon)

• Normal variant • Malocclusion • Condylar hyperplasia • Splinting reaction to TMJ pain • Congenital unilateral hyperplasia • Joint effusion due to trauma • Hemangioma or neurfibroma induced jaw hyperplasia • Tumor in TMJ region (benign or malignant)

Deformed Mandibular Shape

(common) (uncommon)

• Condylar hyperplasia • Trauma with mal-union • Condylar ankylosis (early) • Mandibulofacial dysostosis (Treacher Collins syndrome) • Cystic hygroma • Flawed panoramic technique • Neurofibroma • Hemignathia • Congenital hypo- or hyperplasia of condyle • Hemifacial atrophy (Romberg’s disease) • Klippel-Feil anomalad • Congenital scapular elevation • Torticollis • Electrical or thermal burns • Radiation therapy in childhood

Increased Vertical Depth of Mandible

(common) (uncommon)

• Normal variant • Prognathism • Anatomic enlargement of jaw • Periostitis ossificans • Benign tumor (e.g. ameloblastoma; ossifying fibroma) • Thalassemia • Other congenital anemias • Sclerosteosis • Van Buchem’s disease

Unilateral Failure of Condylar Development

(common) (uncommon)

• Early trauma (e.g. forceps delivery) • Childhood infections around TMJ (e.g. mastoiditis; otitis media or externa; dental or skin abscess) • Lateral facial dysplasia • Radiation therapy in childhood • Hemifacial hypoplasia • Linear scleroderma • Benign tumor • Local malignant tumor destruction of growth center • Metastatic malignancy

Bi lateral Failure of Condylar Development

(common) (uncommon)

• Trauma • Mandibulofacial dysostosis (Treacher-Collins Sx) • Cleft palate, micrognathia and glossoptosis (Pierre Robin) syndrome • Juvenile rheumatoid arthritis (Still’s disease) • Congenital dwarfism • Mucopolysacharidoses • Childhood radiotherapy • Progeria (Hutchinson-Gilford syndrome) • Oculomandibulodycephaly (Hallerman-Streiff Sx) • Agnathia or micrognathia • Cockayne’s syndrome

Condylar Hyperplasia

(common) (uncommon)

• True hyperplasia • Benign tumor (e.g. osteochondroma) • Influence of adjacent vascular or neural tumor • Acromegaly • Hypertrophic arthritis • Malignant tumor (e.g. chondrosarcoma) • Fibrous dysplasia • Paget’s disease of bone •

Prognathism

Multiple Jaw Fractures

Multiple Fractures

(common) (uncommon)

• Severe trauma • Child abuse • Osteogenesis imperfecta • Juvenile idiopathic osteoporosis • Achondrogenesis • Osteopetrosis • Pyknodysostosis • Mucolipidoses • Metaphyseal dysplasia • Homocystinuria • Idiopathic

Suspected Jaw Fractures

(common)

• True fractures • Suture lines • Vascular channels • Fistulous tracts • Symphysis menti (neonate) • Osteomyelitis with fragmentation • Pharyngeal air space shadow • Vertebral superimpositions • Base of skull superimpositions

Suspected Jaw Fractures

(uncommon)

• Previous radiation therapy • Hyoid bone superimposition • Radiodontic artifact • Large sequestra • Pathologic fracture

Pathologic Fractures

(common) (uncommon)

• Oral squamous cell carcinoma • Central bone malignancy (e.g. multiple myeloma) • Metastatic carcinoma • Osteoradionecrosis • Severe osteomyelitis • Marked alveolar atrophy • Scleroderma (systemic sclerosis) • Langerhans’ cell disease

Suspected Hyoid Fracture

• Normal cartilagenous septae • Superimposition artifact • Severe blunt trauma • Hanging (often suicide) • Homicide (strangulation)

Radiolucency in Condylar Head

• Ely’s cyst of degenerative joint disease • Rheumatoid arthritis • Projection artifact (e.g. pterygoid pit; air cells extending into zygomatic arch) • Bifid condyle • Previous trauma • Villonodular synovitis • Central giant cell granuloma /continued

Radiolucency in Condylar Head

• Benign tumor (e.g. myxoma) • Primary malignancy (e.g. osteogenic sarcoma; chondrosarcoma; synovial sarcoma; multiple myeloma; adjacent rhabdomyosarcoma; adjacent glandular carcinomas; lymphoma) • Metastatic malignancy (e.g. hypernephroma; carcinoma from lower gastrointestinal tract)

True TMJ Ankylosis

True TMJ Ankylosis (Common)

(infection) (traumatic)

• Osteomyelitis • Tonsillitis • Otitis media or externa • Mastoiditis • Adjacent soft tissue infection • Dental abscess • Tuberculosis • Mandibular fracture • Forceps delivery

(other)

• Rheumatoid arthritis (Still’s disease) • Ankylosing spondylitis

True TMJ Ankylosis (Uncommon)

(infection) (traumatic)

• Syphilic gumma • Cancrum oris (noma) • Typhoid • Masseter cellulitis • Rheumatic fever • Measles

(neoplasia)

• Invasive malignancy • Osteochondroma • Iatrogenic • Temporal muscle fibrosis • Chronic dislocation of mandible

(other)

• Secondary to burn • Congenital fusion of gums

False TMJ Ankylosis

(common) (uncommon)

• Splinting due to TMJ pain • Malar fracture (fibrous or bony union subsequent to) • Coronoid hyperplasia • Coronoid hyperplasia with campylodactyly • Osteochondroma • Scleroderma (systemic sclerosis) • Hysterical trismus • Temporal muscle fibrosis • Myositis ossificans progressiva • Torticollis • Congenital elevation of scapula

Increased TMJ Space

(common) (uncommon)

• Normal variant • Non-uniform patient positioning • Projection effect (beam angulation) • Posturing of jaw by patient • Displaced articular disk • Effusion into joint • Hemorrhage into joint • Loose body in joint • Acute suppurative arthritis • Displacement due to fracture of condyle or glenoid fossa • Mandibular partial agenesis • Mucopolysaccharidoses

Increased Anterior TMJ Space

• Normal variant • Beam angulation or patient position artifact • Internal derangement of TMJ • Retracted position of condyle due to dental occlusion • Deep overbite • Overclosure of mandible (especially in edentulous) • Rheumatoid arthritis • Absent middle ear

Decreased TMJ Space

(common) (uncommon)

• Excessive vertical angulation of beam during transcranial projection • Arthritis (any kind) • Gross disk displacement • Previous surgical removal of disk • Bony or other true ankylosis

Limited TMJ Movement

(common)

• Normal variant • Pain reaction • Internal derangement of joint • True or false ankylosis

Limited TMJ Movement

(uncommon)

• Scar tissue • Scleroderma (systemic sclerosis) • Fractured zygomatic arch • Coronoid hyperplasia • Malignancy in joint area • Facial Paralysis • Torticollis • Myositis osificans progressiva • Submucous fibrosis • Secondary to high dose radiation

Excessive Translation of TMJ

(common) (uncommon)

• Normal variant • Lax TMJ capsule • Recurrent dislocations • Neurosis • Ehlers-Danlos syndrome

Small Antrum (Normal in Shape)

(uncommon)

• Hemifacial hypoplasia (congenital) • Craniometaphyseal dysplasia (Pyle’s disease) • Cleidocranial dysplasia • Craniofacial dysostosis (Crouzon’s Sx) • Other craniostenoses • Thalassemia and other congenital anemias • Hemifacial atrophy (Romberg’s disease) • Oculomandibulodyscephaly (Hallerman-Streiff syndrome)

Suspected Antral Foreign Bodies

(common) (uncommon)

• Tooth root, or restoration fragment (superimposed or real) • Panoramic ghost shadow • Antrolith • Bony excrescence/septum • Overlying soft tissue calcification • Pellets; bullets; shrapnel; auto glass • Displaced tooth • Broken dental instrument • Drainage tubes • Heavy cosmetics or eyeglass shadow • Aspergillosis

Antral Opacification (Normal Walls)

(common) (uncommon)

• Infectious antritis • Allergic antritis • Mucous retention phenomenon • Mucositis secondary to dental apical pathosis or periodontitis • Hemorrhage following trauma • Antral polyp • Blocked ostia • Antral polyposis • Cystic fibrosis • Mucocele (blocked ostia and antral expansion) • Apical dental cyst (rare) • Aspergillosis

Antral Opacification (Abnormal Walls)

(common) (uncommon)

• Radicular cyst • Other benign cyst or tumor • Fibrous dysplasia (thicker) • Antral hypoplasia (thicker) • Antral malignancy (e.g. carcinoma; lymphoma) • Inverted papilloma • Osteomyelitis • Thalassemia • Agenesis of antrum • Mucormycosis

Antral Opacification (Breached Walls)

(common) (uncommon)

• Oral-antral fistula • Dental abscess • Antral carcinoma • Oral squamous cell carcinoma • Salivary gland malignancy • Infectious antritis • True mucocele • Benign odontogenic tumor (ameloblastoma; myxoma, etc.) • Lymphoma or sarcoma

Absent Nasal Bones

• Severe trauma • Prior surgery • Facial cleft syndromes • Arhinencephaly

Depressed/Absent Nasal Bones

(common) (uncommon)

• Facial cleft syndromes • Previous surgery • Previous trauma • Achondroplasia • Cleidocranial dysplasia • Ectodermal dysplasias • Congenital syphilis • Idiopathic hypercalcemia • Craniometaphyseal dysplasia (Pyle’s disease) • Arhinencephaly • Acrodysostosis

Hypoplasia of Maxillary and Malar Bones (common)

• Mandibulofacial dysostosis (Treacher Collin’s syndrome • Achondroplasia • Craniofacial dysostosis (Crouzon’s syndrome) • Acrocephalysyndactyly (Apert’s syndrome)

Hypoplasia of Maxillary and Malar Bones

(uncommon)

• Bird-headed dwarfism • Congenital telangiectatic erythema with growth retardation (Bloom’s syndrome) • Cochayne’s syndrome • De Lange syndrome • Oculoauriculovertebral dysplasia (Goldenhar’s syndrome • Leprechaunism (Donohue’s syndrome) • Long arm 18 deletion syndrome • Long arm 21 deletion syndrome

/continued

Hypoplasia of Maxillary and Malar Bones

(uncommon)

• Marshall syndrome • Mietens-Weber syndrome • Oculodento-osseous dysplasia • Oculomandibulodyscephaly (Hallerman Streiff syndrome) • Oral-facial-digital syndrome • Oropalatal digital syndrome • Progeria (Hutchinson-Gilford syndrome)

/continued

Hypoplasia of Maxillary and Malar Bones

(uncommon)

• Pyknodysostosis • Rubenstein-Taybi syndrome • Russel-Silver syndrome • Trisomy 13 • Trisomy 18 • Weill-Marchesani syndrome

Enlarged Maxilla

(common) (uncommon)

• Normal variant • Relative to mandible

(see “retrognathia”)

• Influence of adjacent or contiguous vascular tumor • Paget’s disease of bone • Fibrous dysplasia • Osteopetrosis • Juvenile hypothyroidism (cretinism) • Thalassemia • Influence of adjacent or contiguous neural tumor • Craniopharyngioma

Cleft Palate

(common) (uncommon)

• Cleft lip and palate • Isolated cleft palate (unilateral vs bilateral; anterior vs posterior; complete vs incomplete) • Arhinencephaly • Cleft palate, micrognathia and glossoptosis (Pierre Robin syndrome) • Miscellaneous other craniofacial syndromes

Soft Tissue Signs

Radiologic Signs Concerning Facial Soft Tissues

• Calcifications of facial soft tissues • Calcifications in muscle and subcutaneous tissues • Widespread soft tissue calcification • Solitary large calcified mass adjacent bone • Lymph node calcifications • Calcifications in submandibular gland region

/continued

Radiologic Signs Concerning Facial Soft Tissues

• Calcification in parotid duct region • Sialolithiasis • Air in soft tissue • Nasopharyngeal mass • Macroglossia • Salivary gland enlargement • Ductal stricture on sialography

/continued

Radiologic Signs Concerning Facial Soft Tissues

• Increased retropharyngeal space (child) • Increased retropharyngeal space (adult) • Soft tissue mass with underlying bone involvement • Suspected soft tissue tumor shadow

Calcification in Facial Soft Tissues

(common) (uncommon)

• Myositis ossificans • Calcified acne • Calcified lymph node (often post tuberculosis) • Phleboliths • Calcified hematoma (traumatic) • Myositis ossificans progressiva • Ehlers-Danlos syndrome • Calcified adipose tisssue • Scleroderma (systemic sclerosis) • Non-calcification (e.g. tooth displaced into soft tissues) • Calcinosis universalis • Cysticercosis • Hypervitaminosid D

Calcifications in Muscles and Subcutaneous Tissues

(common)

• Dermatolysis and calcinosis • Gout • Scleroderma (systemic sclerosis) • Vascular calcifications • Rheumatoid arthritis • Healing abscess

Calcifications in Muscles and Subcutaneous Tissues

(uncommon)

• Hyperparathyroidism • Hypoparathyroidism • Multiple nevoid basal cell carcinoma syndrome (Gorlin and Goltz syndrome) • Ehlers-Danlos syndrome • Idiopathic hypercalcuria • Myositis ossificans (traumatic and progressiva)

/continued

Calcifications in Muscles and Subcutaneous Tissues

(uncommon)

• Paraplegia • Calcified parasites (e.g. cysticercosis) • Carbon monoxide poisoning • Fracture segment • Tumoral calcinosis • Secondary to thermal burn or frostbite • Benign or malignant soft tissue tumor • Lupus erythrematosus

Widespread Calcification in Soft Tissues

(common)

• Calcinosis universalis • Hypoparathyroidism • Scleroderma (systemic sclerosis) • Multiple vascular calcifications

(uncommon)

• Gout • Hyperparathyroidism • Immobilization • Lupus erythematosus • Cysticercosis • Tumoral calcinosis • Idiopathic hypercalcemia • Gross metabolic bone breakdown/metastatic calcification

Vascular Calcification

(common)

• Carotid atherosclerosis • Hemangioma • Ranine varices • Phleboliths • Familial arteriosclerosis

(uncommon)

• Secondary arteriosclerosis (e.g. diabetes; Cushing’s Sx; nephrotic Sx)

(rare)

• Monkberg’s sclerosis • Enchondromatosis hemangiomata Sx (Maffuci’s syndrome) • Aneurysm • Progeria (Hutchinson Gilford syndrome) • Lipodystrophy • Renal transplantation • Werner’s syndrome • Generalized calcification of infancy

Solitary Large Calcified Mass Adjacent to Bone

(common)

• Sialolithiasis in Wharton’s duct (superimposition) • Calcified fat • Calcified hematoma

(uncommon)

• Scleroderma (systemic sclerosis) • Osteochondroma • Gout • Hyperparathyroidism • Soft tissue osteo- or chondrosarcoma • Tumoral calcinosis • Myositis ossificans • Foreign body

Calcification in Lymph Nodes of Face

(common)

• Tuberculosis (active or scar) • Sarcoidosis • Idiopathic

(uncommon)

• Histoplasmosis • BCG vaccination • Coccidiomycosis • Filiaris • Lymphoma • Osteoblastic metastases

Calcification in Submandibular Area

(common)

• Sialolithiasis (in duct or gland) • Root or tooth displaced in soft tissues • Calcified lymph node • Foreign body

(uncommon)

• Phlebolith • Calcinosis universalis • Scleroderma • Radiographic artifact

(rare)

• Chondrodystrophica calcificans congenita • Myossitis ossificans

Calcification in Parotid Area

(common)

• Sialolithiasis (in duct or gland) • Artifact • Phlebolith • Foreign body

(uncommon)

• Calcinosis universalis • Myossitis ossificans • Other soft tissue calcifications including metastatic calcification related to metabolic disease

Sialolith Appearance

(common)

• True sialolith • Film artifact • Superimposition of tooth in soft tissue or in bone • Superimposed tori, exostoses or osteosclerosis • Calcified lymph node • Foreign body

(uncommon)

Air/Gas in Soft Tissue

(common)

• Gas producing odontogenic infection • Surgical emphysema from air rotor or during endodontics • Projection of air in sulci in occlusal view

(uncommon)

• Craters of ulcerative malignancy • Crushing injury to thorax • Persistent severe coughing • Lipomatous accumulation projected over muscle

Nasopharyngeal Mass

(common)

• Adenoids/tonsillar tissue (especially in adolescence) • Infections • Projection of posterior aspect of inferior turbinates

Nasopharyngeal Mass

(uncommon)

• Hematoma • Malignant nasopharyngeal neoplasm (carcinoma; lymphoma; lymphoepithelioma; multiple myeloma; chordoma) • Benign nasopharyngeal neoplasm (juvenile angiofibroma; neurilemmoma, angioma) • Dermoid cyst

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Nasopharyngeal Mass

(uncommon)

• Extension of neoplasm from sphenoid sinus • Extension of neoplasm from nasal passage • Antral-choanal polyp

(rare)

• Sarcoidosis or tuberculosis • Meningioma extending from base of skull • Encephalocoele

Macroglossia

(common)

• Normal variant or spread following loss of teeth • Trisomy 21 (Down’s syndrome) • Acromegaly • Hamartoma (lymphangioma or hemangioma) • Neurofibroma • Edema following trauma or allergic reaction • Primary or secondary amyloidosis • Lingual thyroid

Macroglossia

(uncommon)

• Juvenile hypothyroidism (cretinism) • Glycogen storage disease • Angioneurotic edema • Infant of diabetic mother • Mucopolysaccharoidoses • Muscular dystrophy • Happy-puppet syndrome • Beckwith-Wiedemann syndrome

Salivary Gland Enlargement

(common)

• Paramyxovirus parotitis (mumps) • Sialolithiasis • Idiopathic • Sjögren’s syndrome • Suppurative sialadenitis • Pleomorphic adenoma

Salivary Gland Enlargement

(uncommon)

• Chronic alcoholism • Hormonal imbalance • Malnutrition (e.g. protein deficiency) • Mikulicz’s syndrome • Hashimoto’s disease • Tuberculosis or sarcoidosis • Benign or malignant tumors • Oncocytosis • Mucoviscoidoses

Stricture of Salivary Duct

(common)

• Inflammation • Sialolithiasis

(uncommon)

• Normal variant • Carcinoma • Trauma including factitial injury and surgery • Radiation therapy

Increased Retropharyngeal Space (childhood)

(common)

• Enlarged adenoids and tonsils • Artifact • Retropharyngeal extension of upper respiratory tract disease or odontogenic infection

(uncommon)

• Juvenile nasopharyngeal angiofibroma • Severe chest trauma • Cretinism • Cystic hygroma or hemangioma • Foreign body impaction • Retropharyngeal goiter • Spinal lesion

Increased Retropharyngeal Space (adulthood)

(common)

• Infections extending from upper respiratory tract • Infections extending from odontogenic causes

(uncommon)

• Chordoma • Carcinoma • Retropharyngeal goiter • Zenker’s diverticulum • Rheumatoid arthritis of spine

Soft Tissue Mass with Underlying Bone Erosion

(common)

• Oral squamous cell carcinoma • Kaposi’s sarcoma (often in AIDS) • Nasolabial cyst • Pyogenic granuloma including pregnancy epulis • Other gingival epulides and denture-induced gingival hyperplasia • Neurofibromatosis (blister region) • Salivary gland malignancy • Metastatic malignancy (in extraction site)

Soft Tissue Mass with Underlying Bone Erosion

(uncommon)

• Lymphoma in soft tissues • Malignant lymph node • Amyloidosis • Angioma • Fungal diseases • Hemophilia • Sarcoma in soft tissues