PATHOLOGY, ANATOMIC VARIANTS AND ANOMALIES AS SEEN ON CONE BEAM CT CBCT

Contributors: Kfir Atias (CT Dent Ltd) Alexander Woodham BSc (Hons) (CT Dent Ltd) John Preece DDS, MS (3D Diagnostix) Marcel Noujeim DDS, MS (3D Diagnostix)

Copyright © 2017 by CT Dent Ltd. All rights reserved. This book or any portion thereof may not be reproduced or used in any manner whatsoever without the express written permission of the publisher except for the use of brief quotations in a book review.

Printed in the United Kingdom

First Printing, 2017

CT Dent Ltd. 2 Devonshire Place, London W1G 6HJ United Kingdom www.ct-dent.com

About the editor:

Alexander Woodham Managing Director CT Dent Ltd

Alexander graduated from St George’s University Medical School in 2004 with a degree in Diagnostic Radiography. He started his career at St George’s Hospital in London in general radiography, before moving to Guys Hospital to specialise in dental radiography. He has been with CT Dent as Lead Radiographer and General Manager since 2011.

The use of any proprietary material or systems illustrated in this publication should not be taken to imply any approval from the manufacturers of those materials or systems, or any endorsement of them by CT Dent Ltd. All trademarks remain property of their respective holders, and are used only to directly describe the products being illustrated. Contents

Introduction ...... 04

Viewing a CBCT Scan ...... 05

Neurovascular ...... 06

Bone ...... 14

Calcifications...... 21

Bony & ...... 24

The Dentition ...... 29

Fractures ...... 39

Lower Third Molars ...... 42

Supernumerary Teeth & Odontomes ...... 45

Paranasal Sinuses & Nasal Fossa ...... 48

Temporomandibular Joint ...... 55

Outside of the Dento-Alveolar Region ...... 57

3 Introduction

This book has been written to help you as dental practitioners to recognise how pathology, variants of normal anatomy and anomalies present on CBCT scans.

The contents of this book are not designed to be an exhaustive list but will hopefully give you an idea of findings you may come across when looking at CBCT scans. Some are more common than others, some may need no further follow up and others may require referral for further investigation.

If you see something on a scan that looks the same or similar to anything in this book, further clarification can be gained from a radiology report.

4 Viewing a CBCT Scan

When viewing a CBCT scan any software will separate the data into different planes. You will see these referred to throughout this book. Every scan is shown as if viewing the patient in the anatomical position and viewed in the following anatomical planes:

• Sagittal plane (lateral) • Coronal plane (frontal) • Axial plane (horizontal)

A further term used is transaxial. This is a plane perpendicular (at right angles) to the long axis of a bone or body part. For CBCT this is the long axis of the or maxilla.

Please remember that CBCT has poor soft tissue resolution and it should not be used for assessment of the soft tissue.

5 Neurovascular

This section shows findings associated with the: • Mandibular canal A volume rendered view showing two right sided accessory foramina. This is an anatomical variant. • Mental canal • Incisive canal

Volume rendered and transaxial views of the left side showing a small accessory foramen, and a vascular canal anterior to the mental foramen.

Coronal and sagittal views of the right Coronal and transaxial views of a left sided mandibular molar region showing a bifurcation of the nerve bifurcation extending into the region of the third mandibular nerve. molar. It is in close proximity to a residual root fragment.

Coronal, axial, sagittal and volume rendered views of the lower right third molar region. The mandibular nerve bifurcates into two branches, one passing along the lingual and inferior surface of the apex of the third molar and the second extending along the buccal surface of the root of the third molar coronal to the apex. Distal Mesial 6 A volume rendered view showing two right sided accessory foramina. This is an anatomical variant.

Distal Mesial Axial, coronal and transaxial views of the right lower third molar. The arrows illustrate a small retro molar branch from the mandibular canal which is in contact with the distal root. There is no clearly identifiable cortical separation of the mesial root from the mandibular nerve.

Coronal and transaxial views of a right sided prominent vascular branching anterior to the mental foramen.

7 Coronal view of the right side. The arrows show branching of vascular canals from the mandibular nerve.

Coronal and transaxial views of the right side. There is expansion of the mandubular canal producing a localised increase in vascularity.

Coronal, axial and transaxial views of the mandibular right premolar region showing a series of interconnected vascular canals, and localised areas of vascularity.

8 Sagittal and volume rendered views showing a prominent vascular loop extending from the premolar into the molar region on the left side.

Volume rendered, coronal, sagittal and axial views of the anterior maxilla showing a localised increase in vascularity.

9 Superior Aspect

Inferior Aspect Axial views through the anterior maxilla. A large vascular is shown on the left and extends across the midline.

Coronal and volume rendered views of the maxillary left canine region. A prominent vascular canal is seen extending into the area.

Coronal view of the mandible. The mental nerve is clearly seen in the anterior mandible. This is a bold appearance of the mental nerve.

10 Sagittal and volume rendered views of the right mandible. The arrows illustrate prominent vascular canals that appear to arise directly from the mandibular canal.

Axial and volume rendered views of the anterior mandible. The mental foramen are elongated bilaterally. This is an anatomical variant.

Coronal and axial views of the anterior maxilla showing a deviation of the incisive canal slightly to the right. This is an anatomical variant.

11 Coronal and sagittal maximum intensity projections, transaxial and volume rendered views showing a neurovascular canal in the lateral wall of the maxillary sinus. This is the posterior superior alveolar nerve and vessels.

Coronal, sagittal and axial views of the anterior maxilla showing dilation of the incisive canal and foramen. A finding like this should be monitored as it may be an early indication of development.

12 Transaxial, coronal and axial views showing a large low density, vascular anomaly in the area of the incisive canal and foramen extending posteriorly to the left canine. The incisive canal and foramen appear to be enlarged. Lateral portions of the lesion could represent an uncommon vascular anomaly, Canalis Sinuosis.

13 Bone

This section shows examples of findings related to the bone of the mandible and maxilla.

Coronal and transaxial views of the anterior mandible. A localised area of sclerotic bone is seen inferior to the apices of the left central and lateral incisors. These entities are a common incidental finding on CBCT and have a limited growth potential.

A reconstructed panoramic, axial, coronal and sagittal views showing a small ovoid homogenous area of increased bone density lingual in the left premolar region.

14 Transaxial and volume rendered views showing a high density area extending from the periosteal surface laterally and situated just inferior to the left mental foramen. This is a . An anatomical variant, these generally require no treatment unless they are causing ulceration of soft tissue or have become too large.

Reconstructed panoramic views of the maxilla and mandible showing areas of high density. This is an example of florid cemento-osseous dysplasia (FCOD). A type of cemento-osseous dysplasia, FCOD predominantly occurs in both jaws in multiple quadrants. It is a benign, asymptomatic condition that requires no treatment. 15 Axial, coronal and volume rendered views showing on the lingual surface of the mandible.

Axial and volume rendered views showing two areas of exostosis on the buccal aspect of the maxilla.

16 Coronal and sagittal views showing a mixed density lesion in the right maxilla. This is radiographically consistent with chronic osteomyelitis.

Volume rendered and sagittal views of a lesion in the molar region of the mandible, causing buccal expansion. Clinical evaluation and is suggested for a finding like this.

Volume rendered and axial views showing a bony protrusion on the . This is consistent with .

17 Sagittal maximum intensity projection, transaxial and volume rendered views showing the extension of the nasal spine to be hypertrophic.

Axial, coronal and sagittal views of the right mandible. There is an area of increased density with an irregular mottled pattern, which is interrupting the buccal and lingual cortical plates and the lower border of the mandible. This has the radiographic appearance of a generalised diffuse, chronic osteomyelitis.

Reconstructed panoramic, axial and transaxial views of the left mandible. A Stafne defect is seen on the lingual aspect of the bone at the angle of the mandible. This is a cortical defect always seen near the angle of the mandible below the mandibular canal.

18 Reconstructed panoramic, transaxial and axial views showing bilateral localised areas of increased bony density. These areas are radiographically consistent with localised areas of sclerotic bone.

Coronal and axial views of the left maxilla. The bone exhibits a mottled, sclerotic increase in density suggestive of chronic osteomyelitis.

19 Axial and sagittal views of the right maxilla. In the premolar region is a concavity in the bone. This could be related to a history of a periapical lesion or might be a variation of normal anatomy.

Sublingual Submandibular

Axial views through the mandible showing very pronounced sublingual (in the canine region) and submandibular (in the molar region) gland depressions.

20 Calcifications

This section shows examples of calcifications. Some of the anatomy seen is from outside of the dento-alveolar region.

Sagittal, coronal and axial views of the mandible. A calcified atheroma is seen in the location of the furcation of the carotid artery. Calcified entities are also seen in the soft tissues on the right side inferior and lateral to the mandible. These are suggestive of calcified lymph nodes.

Sagittal and axial views of the mandible and cervical spine. A calcification (small white dot) is seen in the location of the left triticeous cartilage. This is a common finding in adults.

Sagittal view showing calcification of the posterior longitudinal ligament causing a narrowing of the spinal cord. The axial views of cervical vertebra 3 and 4 show the calcification being posterior to the vertebral bodies and also the narrowing of the spinal cord.

21 Axial and sagittal views. A small detached bone fragment is seen posterior to the lingual aspect of the mandible at the level of the genial tubercle. This is a variation of normal anatomy and is due to calcification of a muscle attachment.

Coronal, sagittal and axial views showing a calcification in the soft tissue of the right orbit. It is positioned in the anterior aspect, supero-medially.

Coronal, sagittal and axial views showing a bilateral calcification of the stylohyoid ligaments. The axial view shows the calcification at the level of C2, lateral to the airway. This pattern of ossification could be indicative of .

22 Sagittal view showing calcification of the pineal gland. This is a common incidental finding.

Axial view showing areas of increased density within the superficial soft tissues lateral to the oropharyngeal area (superficial soft tissues of the oralpharynx). These ectopic soft tissue calcifications are considered a common incidental radiographic finding that do not require treatment or referral.

Axial view through the sphenoid bone at the level of the pituitary fossa. The arrows are pointing to curvilinear areas of increased density lateral to the pituitary fossa. These areas are consistent with calcification of the internal carotid arteries and could be indicative that the patient has cardiovascular disease.

23 Bony Lesions & Cysts

This section shows examples of bony lesions and cysts. Histology should be used in addition to radiographic appearance to confirm diagnosis.

Axial, sagittal and coronal views showing a large well circumscribed radiolucency adjacent to the apices of the maxillary right lateral and central incisors. The radiographic appearance is suggestive of a radicular cyst.

Reconstructed panoramic and axial views of the right side of the mandible. An is seen.

24 Axial, sagittal, coronal and reconstructed panoramic views showing a large well circumscribed corticated radiolucency associated with the crown of the developing maxillary right canine and first premolar. This has the radiographic appearance of a dentigerous or follicular cyst.

Axial, sagittal and coronal views of the anterior maxilla showing a well defined radiolucency consistent with an incisive canal cyst. For the lesion to be an incisive cyst the transverse diameter must exceed 0.6mm

Coronal view showing a Coronal view showing a low well corticated low density density lesion on the distal lesion between the roots surface of the root of the of the right mandibular lower left second premolar. canine and lateral incisor, This is consistent with a at the level of the middle . third of the canine root. This is consistent with a lateral periodontal cyst.

25 Reconstructed panoramic and transaxial views showing a associated with the upper right impacted second molar. The lesion is elevating the floor of the maxillary sinus with a mild sinus reaction.

Axial and sagittal views showing an irregular in shape low density area in the left anterior maxilla. The lesion is seen extending from the midline to the premolar area and is situated within the crest with some palatal extension. This has the radiographic appearance of being a residual inflammatory cyst.

Reconstructed panoramic and transaxial views showing a well defined, irregular in shape, low density lesion in the anteior maxilla on the left side. The lesion is associated with the apices of the left central and lateral incisors and the canine. The lingual and buccal cortices are thinned and irregularly expanded. This has the radiographic appearance of a keratocystic . This is a rare, benign and locally aggressive developmental cystic .

26 Sagittal and coronal views of a right sided ciliated cyst. This is a rare lesion and appears as a delayed complication after surgery in the maxillary sinus, midface osteotomies, traumatic tooth extraction and maxillary fractures.

Coronal and transaxial views of the left mandible. A low-density lesion is seen extending from slightly anterior of the mental foramen to the molar region. The lesion is well circumscribed and has caused expansion and thinning of the buccal and lingual cortical plates. The mandibular nerve has been displaced inferiorly and curves along the inferior and anterior surfaces of the lesion.

27 Axial and coronal views of the left mandible. There is an extensive, multilocular radiolucency extending from the body of the mandible to the ramus. There are varying degrees of radiolucency, suggesting there has been some bony infill and that this is a residual/recurrent lesion, following previous treatment. With no bucco-lingual expansion, this is most likely a odontogenic keratocyst.

Coronal view of the right maxilla. This is a Coronal and sagittal views of the maxillary residual cyst, elevating the sinus floor. right molar region. There is a radicular cyst on the second molar elevating the floor of the maxillary sinus.

28 The Dentition

This section shows examples of pathology and anomalies of the teeth.

Axial and volume rendered views showing the lower left canine and first premolar to have bifid roots. This is a developmental / congenital anomaly.

Transaxial view of the right Axial and transaxial views of the right maxillary central incisor maxillary central incisor showing the pulp chamber and root canal to be calcified. showing external root resorption on the buccal aspect of the tooth.

Transaxial view of the right Axial and transaxial views showing bilateral dens in dente of the mandibular third molar maxillary lateral incisors. showing .

29 Axial and coronal views of the maxillary right second molar. There is an accessory root on the buccal surface of the molar between the two primary buccal roots. This is an uncommon variation in developmental tooth morphology.

Axial and coronal views of the maxillary right second molar. A small is seen on the lingual surface.

Axial, sagittal and coronal views of the maxillary left third molar. The Transaxial view of the tooth exhibits an anomalous crown formation with a mildly enlarged mandibular right third pericoronal space, consistent with an early dentigerous cyst. molar. A small accessory root is seen extending bucally.

30 Coronal view of the maxillary left second and third molars. The palatal root of the second molar presents with apical resorption as a direct result of the impacted third molar.

Axial, coronal, transaxial and volume rendering views of the maxillary left incisors showing germination. There is a common union of the crowns and a communication between the pulp tissues. This is a developmental/congenital anomaly.

Coronal and transaxial views showing resorptive changes of the root apices in multiple maxillary teeth.

31 Axial and transaxial views of the maxillary left canine. An area of resorption is seen at the mid height level on the distal palatal aspect, which has been occupied by bone. This is suggestive of ankylosis.

Axial, sagittal and coronal views of the maxillary right central incisor. An irregular area of radiolucency is seen within the root of the tooth. This is consistent with internal resorption.

Coronal, axial and sagittal views of the anterior maxilla. The periodontal ligament space of the right central incisor is widened around the palatal and buccal aspects of the root and also around the root apex. This could be related to the endodontic treatment of the tooth or previous trauma.

32 Coronal, axial and sagittal views of the right maxillary central incisor region. There is a residual root tip surrounded by a lesion extending to communicate with the alveolar crest. The lesion is thinning the buccal and palatal cortices with no interruption.

Axial, coronal and sagittal views of the maxillary left first molar. A well circumscribed radiolucent lesion is seen surrounding the palatal root which is perforating the lingual cortical plate and mildly expanding into the maxillary sinus. The radiographic appearance is consistent with periapical inflammatory disease of pupal / periodontal origin. Also seen are multiple small irregular areas of high density consistent with endodontic sealing material which have been expressed beyond the apex of the tooth.

Coronal view of the anterior maxilla and transaxial view of the maxillary left lateral incisor. is seen with interruption of the buccal cortex.

33 Axial, coronal and transaxial views of the maxillary right lateral incisor. A small well circumscribed radiolucency is seen associated with the apex. The root also exhibits a prominent .

Axial, coronal and sagittal views of the maxillary right second molar. A well circumscribed, corticated radiolucency is seen surrounding the apex. This may potentially be of pulpal origin.

Coronal and axial views of the anterior maxilla and transaxial view of the maxillary right central incisor. There is a periapical lesion causing slight expansion of the buccal cortex, but with no interruption.

34 Sagittal, axial and coronal views of the right maxilla. The third molar is impacted in a mesio-angular direction causing root resorption on the second molar.

Coronal and transaxial views of the maxillary right canine. The two black arrows show two unfilled canals that join together to exit through the apical one third of the canine root. There is also a periapical radiolucency associated with the apex of the canine.

Coronal views of the right maxillary molar region. There is a periapical lesion on the first molar interrupting the floor of the sinus and involving the second molar.

35 Coronal views showing the left mandibular second molar. Endodontic filling material is extruding from the apical foramina of both roots and periapical lesions are also seen.

Coronal and transaxial views of the right maxillary first premolar. Some endodontic filling material is seen on the buccal aspect of the apical third of the root with interruption of the buccal cortex.

Coronal views of the mandibular right and Transaxial view of the right maxillary first molar. left first molars. The right molar has a lesion Endodontic filling material is extruding from the involving both apices. Endodontic filling material palatal apex and situated within the thickened is extruding from the apical foramen of the sinus mucosa. This mucosal thickening is likely mesial root of the left molar.. to be a response to the presence of the filling material in the sinus cavity.

36 Axial, reconstructed panoramic and transaxial views of the anterior maxilla. A prominent surgical defect on the labial surface of the maxillary right lateral incisor is seen. This appears consistent with an apicoectomy scar.

Sagittal, axial and reconstructed panoramic views of the maxillary right canine. The tooth is impacted lingual to the maxillary right central and lateral incisors.

Coronal view of the maxillary left third molar. A dilaceration of the distal root is seen.

37 Coronal and transaxial views of the left side of the mandible. The second molar exhibits a dilaceration distally, with the root appearing to extend into the cortex. A prominent accessory vascular canal is also seen extending superiorly from the mandibular canal and follows the curvature of the root of the second premolar. The mandibular canal passes in close proximity to the dilacerated portion of the second premolar and the accessory vascular canal to the superior portion of the root. There is no clearly identifiable cortical separation between both canals and the root.

38 Fractures

This section shows examples of fractures of the teeth and alveolar bone.

Coronal, transaxial and volume rendered views of the left mandibular first molar. A vertical fracture is seen through the centre of the tooth and a horizontal fracture through the distal root.

Transaxial and axial views of the maxillary right first molar. A fracture is seen extending completely through the tooth to the trifurcation.

39 Coronal and transaxial views of the maxillary left central incisor region. The white arrows point to fractures of the alveolar crest immediately adjacent to the central incisor. The periodontal ligament space is also widened, a direct result of the fracture.

Transaxial view of the Transaxial view of the maxillary right central right maxillary central incisor showing a incisor. The arrow horizontal fracture indicates a localized through the apical third fracture of the labial of the tooth. cortical plate adjacent to the mesial surface of the central incisor.

Coronal, axial and transaxial views of the anterior maxilla. There is a fracture through the mid third of the right central incisor.

40 Axial and coronal views of the maxillary right first premolar showing a vertical fracture.

Transaxial and axial views of the anterior maxilla. The periodontal ligament space of the right central incisor appears to be widened. There is also a discontinuity of the labial cortical plate which has the appearance of a fracture.

41 Lower Third Molars

This section shows examples of the relationship of the lower third molar with the neurovascular bundle.

Distal Mesial

Axial, coronal and transaxial views of the lower right third molar. The arrows indicate the inferior dental canal. The canal passes in close proximity along the lingual surface of the apex of the distal root without a clear identifiable cortical separation between the canal and the apical portions of the root.

42 Distal Mesial

Axial, coronal and transaxial views of the lower left third molar. The inferior dental canal passes along the superior surface of the distal root and along the lingual surface of the mesial root without a clearly identifiable cortical separation between the canal and roots of the tooth. The roots appear to exhibit hypercementosis and there is a well circumscribed mixed density lesion noted inferior to the apex of the mesial root, consistent with cemental/osseous dysplasia. The roots are positioned on the lingual surface of the alveolar process and appear to be thinning and potentially perforate the lingual cortical plate.

Axial, coronal and transaxial views of the lower left third molar. The inferior dental canal passes along the inferior and lingual surfaces of the roots without a clearly identifiable cortical separation between the canal and the apices of the tooth.

Distal Mesial

43 Coronal and transaxial views of the lower left third molar. The tooth is impacted in a horizontal direction, with fused roots. The superior aspect of the inferior dental canal is in contact with the mesial aspect of the crown and root of the tooth.

Distal Mesial

Reconstructed panoramic and transaxial views of the lower right third molar. An accessory branch is seen extending from the mandibular canal, running along the inferior buccal surface of the impacted and unerupted third molar.

Distal Mesial

Axial, coronal and transaxial views of the right mandibular third molar. The mandibular canal passes in close proximity to the mesial root of the third molar without a clearly defined cortical separation between the canal and the apex of the tooth. The roots of the third molar extend into and thin the cortical plate.

44 Supernumerary Teeth & Odontomes

This section shows examples of supernumerary teeth and odontomes.

Coronal, sagittal and axial views of the right maxillary molar region. A small supernumerary tooth is seen distal to the developing right third molar.

Axial, sagittal and coronal views showing a mesiodens in the maxilla. The tooth is positioned disto- palatal to the right canine, mesial to the right first premolar and in contact with the palatal cortex. The tooth is in contact with the roots of the canine and the first premolar.

Coronal, axial and sagittal views showing two supernumerary teeth in the maxilla. One is positioned directly lingual to the right central incisor, the second is to the left of the midline, lingual to the premolars.

45 Reconstructed panoramic view of the mandible showing an additional tooth (number 9) in each quadrant. The third molars display hypercementosis and are impacted in mesio-angular directions with their crowns communicating with the roots of the second molars.

Axial, coronal and sagittal views of the right mandible. A supernumerary tooth is positioned on the lingual surface of the alveolar process, in the interproximal space between the second premolar and first molar. The tooth is in close physical proximity to the mesial root of the first molar.

Axial and transaxial views of the right mandible. A supernumerary tooth is positioned on the lingual surface of the alveolar process lingual to the canine and first premolar.

46 Axial, coronal and sagittal views of the anterior maxilla. A small supernumerary tooth with a surrounding low density area is seen on the lingual surface of the alveolar process in the interproximal space of the central and lateral incisors. The radiolucency also seen, may represent early dentigerous cyst formation.

Coronal, axial and sagittal views of the left mandible. A small is seen between the roots of the first and second premolars. It is positioned more towards the lingual crest at the mid-height level of the roots.

47 Paranasal Sinuses & Nasal Fossa

This section shows examples of pathology and anomalies found in the four paranasal sinuses and the nasal fossa.

Coronal and transaxial views of the left maxillary sinus. A fractured root tip is seen in the sinus cavity with a localised reaction.

Coronal and transaxial views of the right maxillary sinus. An area of calcification is seen with a raised mucosal lining.

Coronal and axial views of the midface showing the right aspect of the frontal sinus to be ossified. The walls of the sinus are within normal limits.

48 Axial view through the midface. The sphenoid sinus shows an increase in density and contains bubbles. This appearance is suggestive of an acute exacerbation of a chronic sinusitis.

Axial, coronal and sagittal views of the left maxillary sinus. The sinus cavity is partially filled with a homogenous area of increased density containing bubbles. This appearance is suggestive of an acute exacerbation of a chronic sinusitis.

49 Sagittal, axial and coronal views of the midface. An osteoma is seen on the lateral wall of the right ethmoid sinus with mucosal thickening. Mucosal thickening with air bubble appearance is also seen within the sphenoid sinus on the sagittal view. Osteomas are commonly seen in the paranasal sinuses and their removal is only needed in cases of blockage of the sinus pathways.

Coronal and axial views of the midface. Mucosal thickening is seen in the maxillary sinuses, ethmoid air cells and sphenoid sinuses.

Coronal and axial views of the paranasal sinuses showing severe chronic sinusitis with possible acute phase of exacerbation. The coronal view shows severe mucosal thickening obliterating the whole volume of the right maxillary sinus with extension to the nasal cavity, ethmoid air cells and also obliteration of the osteomeatal complex. Moderate to severe mucosal thickening with air bubbles is seen in the left maxillary sinus. The axial view shows mucosal thickening of the sphenoid sinus with air bubbles.

50 Axial and transaxial views of the right maxillary sinus. There is mucosal thickening in the maxillary sinus and septations, which are a variation in anatomy.

Coronal view of the midface. Homogenous areas of increased density suggestive of fluid accumulation are seen within the right and left maxillary sinuses. The right and left osteomeatal complexes appear to be obstructed. There are also thickened sclerotic outlines. Localised increases in the thickness and density of the tissues lining the ethmoid sinuses is also seen.

Sagittal view of the right maxillary sinus. There is mild mucosal thickening seen along the walls of the right maxillary sinus with multiple calcifications within the thickening. These calcifications are antroliths which are usually found in long standing presentations of chronic sinusitis.

51 Coronal view of the maxillary sinuses. The right maxillary sinus contains an irregular area of increased density. This is suggestive of an antral polyp. A right sided deviation of the nasal septum is also seen.

Transaxial view of the Transaxial view of the maxillary right first molar right maxillary sinus. area. There is an area of The maxillary sinus can interruption of the crest be seen extending into suggesting an oroantral the alveolar bone in the communication. area of the first molar. This is a normal variant of anatomy.

Sagittal, coronal and axial views of the midface. The right maxillary sinus is almost completely occupied by a homogenous area of increased density containing small geometrically shaped homogenous areas of increased density. The left maxillary sinus and a part of the ethmoid sinus are completely occupied by a homogenous area of increased density, also containing multiple geometrically shaped homogenous areas of increased density. The right osteomeatal complex is patent whereas the left appears obstructed. These findings are consistent with a moderate to severe chronic sinusitis of the right and left maxillary sinuses and left ethmoid sinus. The geometric areas of increased density are more suggestive of bone graft materials rather than antrolith formation, which is typically more irregular in shape.

52 Coronal view showing a mild left sided Coronal view of the maxillary sinuses showing small deviation of the nasal septum. This is a osteomas bilaterally on the lateral walls. common incidental finding and does not require treatment or referral unless there are breathing difficulties through the nose.

Coronal view of the maxillary sinuses. The features Coronal view of the maxillary sinuses. The left seen are consistent with a history of functional and right maxillary sinuses are hypertrophic with endoscopic sinus surgery (FESS). severe mucosal thickening occupying the whole volume of the right sinus. Hypotrophy of the maxillary sinuses is a variation of normal anatomy.

Coronal, sagittal and axial views of the left maxillary sinus. A small localised area of increased density is seen within the thickened lining of the maxillary sinus. The irregular shape is consistent with an antrolith.

53 Axial and sagittal views showing an osteoma on the postero-lateral wall of the left maxillary sinus.

Coronal view of the maxillary sinuses. A small dome shaped area of increased density is seen within the right maxillary sinus. This is consistent with a small mucus retention pseudocyst. These are common findings that do not require further assessment, unless blocking the osteomeatal complex. They usually regress spontaneously.

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This section shows examples of bony pathology of the temporomandibular joints.

Coronal, axial, sagittal and volume rendered views of the temporomandibular joints. The right condyle has severe flattening and erosion of the anterior superior condylar surface on the lateral pole with most of the condylar structure destroyed. There are corresponding erosive lesions and sclerosis on the posterior slope of the articular eminence. The left condyle has broad flattening and severe erosion of the superior cortical surface, with areas of irregular projections of bone remaining. This appearance is consistent with rheumatoid arthritis.

55 Coronal, axial, sagittal and volume rendered views of the temporomandibular joints. The right condyle exhibits mild, localised sclerotic changes in the cortical layer suggestive of an early, mild degenerative joint disease.

Right Axial, reconstructed panoramic and sagittal views of the temporomandibular joints. Detached calcified areas anterior to the head of the condyle are seen bilaterally. This is consistent with chondrocalcinosis.

56 Outside of the Dento-Alveolar Region

This section shows some examples of findings outside of the dento-alveolar region from larger field of view CBCT scans.

Sagittal view of the nasopharynx. A mild localized increase in the thickness of the tissues in the posterior superior oral pharynx is seen indicating enlargement of the adenoids

Axial and sagittal views of the midface. A small metallic density is seen on the internal angle of the right eye.

57 Axial and coronal views showing a localised bony increase in density surrounding the structures of the middle ear. These areas may represent bony change associated with chronic middle ear infection/inflammation. The right and left external auditory meatuses are partially obstructed by irregular areas of increased density suggestive of ear wax accumulation.

Sagittal view of the nasopharynx and oropharynx. Sagittal view of the upper cervical spine. There is a Hypertrophy of the pharyngeal tonsils is seen. well circumscribed radiolucency in C2 suggestive of a solitary bone cyst.

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