Small fov cb ct

Data collectionCritical thinking

Comprehensive reasoningDiagnosis

Treatment plan

Extraction of hopeless teeth

Operative phase

Endodontic therapy and provisionalization

Soft and hard tissue correction/augmentation

Occlusal equilibration/correction

Soft and hard tissue correction/augmentation

Extraction of questionable teeth

Implants - surgical phase

Provisionalization

Patient OHI complianceEndo reassessment

Soft and hard tissue response

Impression taking

Framework try-in

Porcelain/zirconia assessment

Esthetic artistry

Cementation

Long term maintenance

Foundational Cypher

Ongoing reassessmentCreate stable plateaus

Endo

PerioImplant

Medical/Dental history Articulated models

Flat field radiographyCone beam tomography

Periodontal probingOcclusal assessment

Patient objectivesPatient compliance;

physical and emotionalTeam approach;

laboratory professional

Orthodontics

Techniques Effective Dose (µSv)Intraoral radiograph (per exposure) 1 to 8

Dental panoramic radiograph 4 to 30

Cone beam CT (small field of view) 5 to 35

Cone beam CT (large field of view) 70 to 550

Full mouth series 30 to 150

CT scan (maxilla and mandible) 75 to 100

CT scan (skull) 400 to 1000

Medical CT 1200 to 330

Comparison of the effective dose of different radiographic techniques (McCullough CH, Schueler BA. Calculation of effective dose. Med. Phys. 2000;27:828-838)

0 75 150 225 300Time period for equivalent effec:ve dose from natural background radia:on in days

CT maxilla and mandible

CT maxilla or mandible

CBCT large FOV

Denver, CO per year

FMX

Bitewings (4)

Kodak 9000 3D mand posterior

Kodak 9000 3D mand anterior

Kodak 9000 3D panoramic

Kodak 9000 3D max ant and post

Intraoral periapical

0 75 150 225 300Time period for equivalent effec:ve dose from natural background radia:on in days

CT maxilla and mandible

CT maxilla or mandible

CBCT large FOV

Denver, CO per year

FMX

Bitewings (4)

Kodak 9000 3D mand posterior

Kodak 9000 3D mand anterior

Kodak 9000 3D panoramic

Kodak 9000 3D max ant and post

Intraoral periapical

Rad: obsolete unit of radiation absorbed dose, equal to .01 gray Rem: obsolete unit of radiation dose equivalent

The “Sievert” is the preferred term - Sievert (Sv):1uSv* = .0001rem1 day background radiation: 6 - 7uSv

Yearly background radiation: @2400uSv

Principals of CBCT – VOXEL

50 mm

.38 mm

.076mm

.076mm

.076mmCubic Voxel

✦ Voxel (VOlume piXEL), is short for ‘volumetric pixel’ and is the smallest “box-shaped” building block of a 3-D image

✦ Voxel (VOlume piXEL), is the smallest building block of a 3-D image

✦ Simulated bone defects in acrylic blocks and the human mandible proved that CBCT is an accurate way to measure osseous lesion and volume

Pinsky HM, Dyda S, Pinsky RW, Misch KA, Sarment DP. Accuracy of three-dimensional measurements using CBCT. DentomaxillofacRadiol 2006:35;410-416

Principals of CBCT – VOXEL

50 mm

.38 mm

.076mm

.076mm

.076mmCubic Voxel

Pinsky HM, Dyda S, Pinsky RW, Misch KA, Sarment DP. Accuracy of three-dimensional measurements using CBCT. DentomaxillofacRadiol 2006:35;410-416

The Kodak 9000 3D features a minimum slice thickness of 0.076mm (76u)

0.076mm images are the highest resolution in the industry today

LargeWe care for 3-D patients with 3-D disease & provide 3-D treatment

Shouldn’t we use 3-D technology for diagnosis and treatment planning?

MediumWe care for 3-D patients with 3-D disease & provide 3-D treatment

Shouldn’t we use 3-D technology for diagnosis and treatment planning?

Focused

1. Focused ‘FOV’ provides substantially

lower doses than medium and large FOV cbCT units.

Small FOV cbCT

Axial

Coronal plane

Sagittal plane

Endodontic�� indications�� for�� cbCT

Endodontic�� indications�� for�� cbCT differentiation of pathosis from normal anatomy relationship with important anatomical structuresmanagement of aberrant anatomy (ie: dens, c-shapes) external & Internal resorption root perforations accessory/ missed canal identification management of fractured instruments aiding surgical planningretreatmentstraumatic injuriesintra-operative (ie: finding canals)MSDOcalcified casesfacial pain cases to rule out odontogenic etiology

Sousa Melo et al, 2010

Axial tomographic cross sections at the coronal portion of the root of specimens with similar subtle experimentally induced root fractures show the fracture line (arrows) in nonfilled root (A) and presence of star-shaped streak artifacts of gutta-percha (B) and post (C).

Unfilled

Gutta-percha

Gold post

Sousa Melo et al, 2010

Diagnosis

1. Patient referred for endodontic treatment, tooth #4.62. Sensible to cold testing, tender to percussion3. 7mm probing on distal aspect

Axial view

Diagnosis

Sagittal view

Distal surface

Diagnosis

Diagnosis

DIAGNOSIS

Radiolucency mid-root tooth #2.4

Missed root

Diagnosis

“cbCT showed significantly more lesions (34%, p< 0.001) than PA’s” Low KMT, Dula K, Bürgin W, von Arx T. Comparison of periapical radiography and limited cone-beam tomography in posterior maxillary teeth referred for apical surgery. J Endod 2008;34:557–562

Diagnosis

• Occasionally, apical periodontitis will not penetrate the antral floor, but will displace the periosteum, which will deposit new bone (periapical osteoperiostitis or “halo”).

Detection/Size of Apical Periodontitis

• CBCT is significantly better at demonstrating ‘AP’ than conventional

• x-rays Estrela C et al, JOE 2009• Cotton TP et al, JOE 2007• Lofthag-Hansen S et al, OOOE 2007

In Lieu of CBCT: What Are We Missing?

Lesiondetection


Do we have a lesion?


Identifycomplexity


Extent of lesion

Size of lesion

Mental Foramen

Healing??

One year post-op

Post-op

Retreatment

RetreatmentInitial RCT done 5 years priorRetreatment 2 years priorIntermittent pain and swelling for the past 18 months

Retreatment

Post-op 4.6 1 year post-op 4.6

Retreatment

Preop 12 mos. Postop

Trauma

Help me, treat meow.........

The day of the impact the coronal fragment was stabilized by splinting.

CBCT image aached. One week later tooth is cold sensitive and percussion is painful.

http://www.dentaltraumaguide.org/














































































Trauma

Trauma

Tooth #1.1 PA Tooth #1.1 cbCT

Trauma


Avulsion & Replantation, teeth #‘s1.1 & #2.1

Trauma

Trauma

Alveolar fracture

#1.2 #1.1

Undiagnosed lateral luxa:on

Alveolar fracture

Trauma

Trauma

Complications Perforation

Complications

#2.1: avulsed & replanted

Detection of Luxations


Tooth #1.1 - note alveolar fracture Tooth #2.1 - note change in angulation as compared to tooth #1.1


Tooth #2.4 PA


Tooth #2.4 cbCT

Detection of Perforations

Perforations

• Resorption was detected in 69% of radiographs and 100% of CBCT scans• Estrela C et al JOE 2009


Resorption

Resorption was detected in 69% of radiographs and 100% of CBCT scans

Estrela C et al JOE 2009

Detection of Resorption


?

Root Resorption

External Cervical Invasive Resorption

CBCT- perfectly positioned for endodontics:Focused FOVMinimal radiationHighest resolutionReal-time analysis

Begin with the end in mind

Detection of Root Fractures

CBCT showed higher accuracy than PA’s for the detection of VRF.Confirmed by Hassan B et al, JOE 2009 and Edlund M et al, JOE 2011Nyquist theorem: VRF must be at least 2x voxel size to be visible

C R A C K !

Root Fracture

Root Fracture

C R A C K !

Root Cracks/Fractures

6m follow-up


Pre-op

1.Patient referred for evaluation2.Discomfort to biting/chewing3.Isolated 6mm probing on distal


Root Cracks/FracturesRoot Cracks/Fractures


Sinus tract tracing 7mm

Vertical Root Fracture


No apparent bone loss

Intra-operative

Intra-operative

It appears that there are 2 canals that merge into 1

Initial accessInitial access

Coronal part of tooth

Apical part of tooth

Canals first appear to be visible

Appears to be 1 canal

Intra-operative

Maxillary Sinusitis of Dental Origin (MSDO)

MSDO: When a dental infection extends directly through the sinus floor causing a secondary maxillary sinus inflammation

Abrahams et al found maxillary sinus pathosis in 60% of cases Matilla found mucosal hyperplasia in 80% of cases

‘And in the end the love you take is equal to the love you make’

Small fov cb ct

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