advanced radiographic aids in periodontics

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Advanced diagnostic aids in periodontology Radiographs & imaging

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Page 1: Advanced radiographic aids in periodontics

Advanced diagnostic aids in

periodontology Radiographs & imaging

Page 2: Advanced radiographic aids in periodontics
Page 3: Advanced radiographic aids in periodontics

Introduction A better understanding of the periodontal disease process challenged usefulness of traditional clinical and radiographic methods for diagnosis and prompted revision of outdated diagnostic aids.

Page 4: Advanced radiographic aids in periodontics

DIAGNOSIS

The act or process of identifying or determining the nature and cause of a disease or an injury

Evaluation of patient history

Physical examination

Laboratory investigations

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PRINCIPLES OF DIAGNOSIS

Diagnostic test are assessed in terms of their sensitivity and specificity

Specificity – is the ability of test to clearly differentiate one disease from other

True negative

Percentage of subjects with truly absent disease who have a negative test

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SENSITIVITY - the ability of a test to detect the disease whenever it is present

Percentage of subjects with truly present disease who have positive test

PREDICTIVE VALUE –Probablity that the test result agress with disease status

Positive predictive value-Probablity of disease in a subject with positive test results

Negative predictive valueProbabllity of health in presence of negative test results

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RADIOGRAPHS

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It is the traditional method to asses the destruction of alveolar bone associated with periodontitis.

CONVENTIONAL RADIOGRAPH CAN BE USED TO EVALUATE

Bone levels Bone loss – even or angular patterns Intra(infra) – bony defects Root morphologies ⁄ topographies Furcation radiolucencies Endodontic lesions Endodontic mishaps Developmental anomalies Root length and shape(s) remaining in bone

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RADIOGRAPHS

INTRA ORAL

IOPA,BITEWINGS

&OCCLUSAL

EXTRA ORAL

OPGS

CONVENTIONAL AND DIGITAL

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CONVENTIONAL RADIOGRAPHS

INTRA ORAL RADIOGRAPHS

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Intra oral periapical radiographsParalleling technique

Also called as “right angle” or “long cone technique”. X-ray film is placed parallel to long axis of tooth and central ray of x-ray beam is directed at right angle to teeth & film.Preferable technique for periodontal use.

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Central ray is directed at right angles to a plane bisecting the angle between long axis of teeth & film.

Bisecting angle technique

Projection Maxilla MandibleIncisors +40 degrees -15 degreesCanine +45 degrees -20 degreesPremolar +30 degrees -10 degreesMolar +20 degrees 2-5 degrees

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Extraoral Periapical Radiograph

(Newman And Friedman 2003)

Limitations with intraoral periapical radiographic imaging: Advancing age Anatomical difficulties like large tongue, shallow palate, restricted mouth opening, Neurological difficulties, and size of radiographic sensor

Chen et al in 2007 developed a sensor beam alignment aiming device for performing radiographs using this technique

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aiming device with placement of the sensor

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BITEWING RADIOGRAPHS

Records the coronal part of upper & lower dentition along with periodontium.

USES 1)To study height & contour of interdental alveolar bone. (2)To detect interproximal calculus. (3)To detect periodontal changes Horizontal bitewing radiographs useful for proximal caries

detection limited use in periodontal

treatment and treatment planning if bone loss is advanced

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Vertical bitewing radiographs film is placed with its long axis at 90º to the placement for horizontal bitewing radiography, can be helpful in evaluating periodontium

POSITIONING DEVICES FOR BITEWING

Hawe Paro-Bite Centering Device

a positioning aid is advised to reduce the need for repeat radiographs and hence the unnecessary x-ray exposure is reduced

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Occlusal Radiographs – Intraoral occlusal radiographs enable viewing of a relatively large segment of dental arch.

They are useful in patients who are unable to open mouth wide enough for periapical radiographs

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LIMITATIONS OF RADIOGRAPHS

Conventional radiographs are specific but lack sensitivity

More than 30% of bone mass at alveolar crest must be lost to be recognized on radiographs

Radiographs provide a 2-dimensional view of a 3-dimensional situation,

provides only information about inter proximal bone level.

Radiographs do not demonstrate soft tissue - to - hard tissue relationship hence no information about depth of soft tissue pocket

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STANDARDIZATION OF RADIOGRAPHS

• Constant film position – film holders, stents

• Constant tube geometry - Positioning devices , Cephalostat

• Using paralleling techniques • Using vertical bitewings • Using superimposed mm grid

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Extraoral radiographsExtraoral radiographs are taken when large areas of the skull or jaw must be

examined or when patients are unable to open their mouths

for film placement. Useful for evaluating large areas of the skull and jaws but are not adequate for detection of subtle changes such as the early stages of dental caries or periodontal disease.

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Conventional panoramic

imaging/Pantamography

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LIMITATIONS OF OPG

Image distortion Lingual structures would be projected higher than

buccal surfaces Use of screen film combination results in less details

than intral oral images Production of ghost images

It can be used as a alternative for intra oral full mouth series when combined with bite wing radiographs

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Tugnait et al. 2000,2005 The periodontal structures of interest noted on

periapical radiographs are also noted on panoramic radiographs.

The radiographic features of interest on a panoramic radiograph supplemented when necessary by a small number of intra-oral views, is sufficient for the management of periodontal diseases.

Pepallasi EA et al 2000 Panoramic radiographs may not reveal alveolar bony defects as accurately as periapical radiographs.

But question is whether there is any additional therapeutic yeild from greater accuracy from IOPAs

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Vazquez et al 2007

Determined the efficacy of panoramic radiographs in the preoperative planning of posterior mandibular implants

mental nerve parasthesia following implant placement in 1527 patients with 2584 implants with only OPGs as preoperative imaging technique

No permanent sensory disturbances of the inferior alveolar nerve

Only 2 cases 0.08 %reported paresthesia

Panoramic examination safe preoperative evaluation tool

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Digital radiography Digital radiography is a superior alternative for film based imaging

Digital in digital radiography means numeric format of image content as well as its discreteness

Images are numeric and discrete in two ways – • Spatial distribution of picture elements (pixels) and

• In terms of different shades of gray of each of pixels• Collections of individual pixels organized in a matrix of rows and columns

Digital image

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DIGITAL RADIOGRAPHY

Direct Method

Uses a Charge Couple Device (CCD) or CMOS sensor linked with fiberoptic or other wires to computer system

CCD receptor is placed intraorally as traditional films , images appear on a computer screen which can be printed or stored

Indirect Method

This method uses a phosphor luminescence plate, which is a flexible film like sensor placed intraorally & exposed to conventional x-ray tube.

A laser scanner reads the exposed plates & reveals digital image data.

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Direct Digital ImagingComponents• X-ray source• an electronic sensor, • A digital interface card, • a computer with an analog

to- digital converter (ADC), • a screen monitor, software,

and a printer.

Direct digital sensors- charge-coupled device (CCD) or complementary metal oxide semiconductor active pixel sensor (CMOS-APS).

array of X-ray or light sensitive pixels on a pure silicon chip.

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Indirect imagingPhotostimulable phosphor radiographicsystems

PSP is scanned with a helium-neon laserbeam. The emitted light is captured and intensifi edby a photomultiplier tube and then converted intodigital data.

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ADVANTAGES image can be instantly viewed by patient &

dentist. Reduction in radiation received by patient by as

much 50% to 80%

Images can be altered to achieve task specific image characteristics for eg. density & contrast can be lowered for evaluation of marginal bone and increased for evaluation of implant components.

enables the dental team to conduct remote consultations.

Computerized images can be stored, manipulated & corrected for under & overexposure

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DISADVANTAGES

Familarity with digital nature of images and understanding of principles of image manipulation is required

Lack of infection control.

Patient discomfort during placement.

As image can be easily manipulated, it can be misused in legal proceedings

Grossly overexposed or underexposed images cannot be corrected

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Radiovisiography (RVG)

Duret F et al (1988)

Based on use of CCD

Radio – X-ray generator connected to sensorVisio – storage of incoming signals during exposure and convertion to gray levelsGraphy – digital mass storage unit – connected to various video printout devices

latest version

Trophy has released a wireless version of their RVG intraoral sensor named the RVG 6500.

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Mechanism of image displayRadiographic digital

detector

Conventional radiographic source

used to expose sensor

Detector converts X-rays to visible image

Image display on monitor

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Mouyen F et al (1989): The RVG system when compared with conventional uses considerably reduced levels of radiation to produce an image immediately after exposure..

Adosh L in 1997 in a comparative study for marginal bone between RVG and after surgical exploration presented that Majority showed difference of less than 0.5 mm between two techniques

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The radiographic measurements overestimated interproximal bone loss as compared to the intrasurgical measurements:

A.R. Talaiepour et al in 2005 evaluated the accuracy of RadioVisioGraphy

(RVG) in the linear measurement of interproximal bone loss in intrabony defects.

Comparison between RVG measures and intrasurgical estimates were performed in 56 teeth with intrabony defects

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Diagnostic efficacy of digital imaging

with regard to periodontal lesions

Nair et al. 2000 investigated the accuracy of alveolar crestal bone detection utilizing Ektaspeed Plus film, Sidexis direct digital images, and brightness-enhanced digital images. No significant differences were found

Wallace et al 2004 Demonstrated that E film displayed the highest sensitivity and specificity followed by PSP and CCD images when observers were able to adjust digital image contrast and brightness enhancements.

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Specialized techniques

Introduction of digital radiography applications with meaningful in dentistry diagnostic utility

Early detection

Quantitative assessment

3 D imaging

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Digital subtraction radiography

Zeidses des Plantes (1935) : 1st demonstrated use of subtraction imaging Depends up on conversion of serial

radiographs into digital images.

The serially obtained digital images are superimposed & image intensities of corresponding pixels are subtracted

If change has occurred

The brighter area represents gain

Darker area represents loss

.

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This technique facilitates both qualitative & quantitative visualization of even minor density changes in bone by removing the unchanged anatomic structures from image

Base line after one year bone gain

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Ortmann (1994)- 5% of bone loss can be detected. Diagnostic subtraction radiography (DSR) can be used for enhanced detection of crestal or periapical bone density changes and to evaluate caries progression

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STANDARDIZATION

Baseline projection geometry and image density should be reproduced

bite blocks must be made and attached to the film holders and the film holder must be reproducibly aligned to the x-ray beam collimating device

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Several image processing techniques are also developed to reduce the error in DSR

Semiautomated registration Byrd V et al 1998

Automated registration algoritham .Ettinger et al

samarabandhu et al 1994

Computer corrected of distorted projections webber1984

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Overall contrast is improved Trabecular marrow spaces are visualizedEnhancement of low and high density images

no objective descriptionHigh standardization of x raysNo reduction in exposure

ADVANTAGES DISADVANTAGES

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COMPUTER ASISTED DENSITROMETRIC

IMAGE ANALYSIS SYSTEM

Introduced by Urs Brägger et al 1988

A video camera mesaures the light transmitted through the a radiograph

Signal are converted to grey scale images

Camera is interfaced with computer and image processor for storage and mathematic manipulation of image

Offers an objective method for studying alveolar bone changes quantitatively

High degree of sensitivity ,accuracy and reproducablity

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Urs Brägger et al in 1988

CADIA was more sensitive than subtraction radiography

CADIA was capable of assessing differences in remodeling activity over 4–6 weeks after periodontal surgery

Objective method to quantify alveolar bone density

Deas et al 1991

on monitoring the relationship of CALs and CADIA, found that prevelance of progressive lesions as detected by radiograph is higher than previous accepted data

CADIA is still used in research purposes for detecting quantitatively the alveolar bone density

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Computer-Based Thermal Imaging

Compare the rewarming rates of normal and inflamed human gingiva

gingival temperature measurement Valuable objective method for the diagnosis of periodontal diseases

Infra-red thermography provides a non-invasive method

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Probeye Thermal Imaging Systems

The camera's lOx lens provides a spatial resolution of 0.1 mm at a distance of approximately 15 cm from the gingiva.

composed of indium antimonide which detects wave lengths from 2000 nm to 5600 nm

Technique is no more in use

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Extra oral digital imaging

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Conventional tomography Designed to image a slice or plane of tissue

Accomplished by blurring the images lying outside the plane of interest

It consists of an x ray tube and radiographic film rigidly connected which moves about a fixed axis and fulcrum

As exposure begins tube and film move in opposite direction simultaneously .

Objects located with in the fulcrum remain in fixed positions and are viewed clearly

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Used less frequently with the introduction of:

MRI , CT and Cone beam imaging

OPG is a variant of conventional Tomography

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Computed tomography Godfrey Hounsfield and Allan MacLeod Cormack (1979) shared Nobel prize

Consists of a x ray tube emitting finely collimated x ray beam directed through the patient to a series of scintillating detectors or ionizing chambers

Detectors form a continuous ring and x-ray tube moves in a circle with in the ring

Patients lie stationary and x ray tube rotates one turn .Then the table will move 1 to 5 mm to next scan

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HELICAL CT

Introduced in 1989

The gantry containing x ray tube and detectors continuously revolve around the patient ,where as patients table advances through the gantry.

Result is acquisition of a continuous helix of data.

DETECTORS

Gas filled ion chambers xenonSolid state detectors cadmium tungstate

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CT Image construction

Computer algorithms use photon counts to construct digital CS images

Images are displayed in individual blocks -----VOXELS

Each square of the image is matrix----PIXELS

Each pixel is assigned a CT number representing tissue density

CT number HOUNSFIELD units

Range -1000 to 1000

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ADVANTAGES

Eliminates superimposition of images of structures outside area of interest

High contrast resolution – differences between tissues that differ in density < 1% - can be distinguished

Images can be viewed in axial coronal and sagittal planes

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Naito T et al. 1998, Pistorius A et al. 2001.Used Computed tomography (CT) in studies in relation to periodontal defects.

CT does not offer any favourable cost benefit, dose exposure or therapeutic yield advantage in periodontal practice and is unlikely to find a routine

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CONE BEAM COMPUTED TOMOGRPHY Developed in 1982 for angiography

Utilizes cone shaped source of ionizing radiation & 2D area detector fixed on a rotating gantry .

Multiple sequential images are produced in one scan

• Rotates 360° around the head

• Scan time typically < 1 minute

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• Image acquisition involves a Rotational scan of a x ray source and reciprocating area detector moving synchronously around patients head

• Many exposures are made at fixed intervals to form basic images.

• Software programs are used to reconstruct 3D images

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Image reconstruction

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INTERFACE CONE-BEAM CT MANAGEMENT SOFTWARE

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INDICATIONSEvaluation of the jaw bonesImplant placement and evaluation evaluation TMJ Bony & Soft tissue lesionsPeriodontal assessmentEndodontic assessmentAlveolar ridge resorption Orthodontic evaluationAirway assessmentNeed for 3D reconstructions

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panoramic cbct

superimposition

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CT V/S CBCT

Conventional CT scanners make use of a fan-beam and Provides a set of consecutive slices of image

Conventional CT makes use of a lie-down machine with a large gantry.

Greater contrast resolution &

More discrimination between different tissue types (i.e. bone, teeth, and soft tissue

Utilize a cone beam, which radiates from the x-ray source in a cone shape, encompassing a large volume with a single rotation.

a sitting-up machine of smaller dimensions

Commonly used for hard tissue Ease of operation Dedicated to dental Both jaws can be imaged at the

same time Lower radiation burden

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Artifacts arising from metal restorations are more severe using conventional CT.

artifacts that arise from metallic restorations are less severe with the i-CAT

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Kelly A. Misch et al . 2006 Compared radiographs with CBCTResults: Three-dimensional capability of CBCT offers a significant advantage in linear measurements for periodontal defect All defects can be detected and quantified.

Mol A and Balasundaram 2008 Evaluated The NewTom 9000 CBCT scanner Results: Better diagnostic and quantitative information on periodontal bone levels in three dimensions than conventional radiography can be obtained

B. BEZAK et al 2010 Assessed reliability and accuracy of Cone Beam Computed Tomography (CBCT) against CAL .CBCT measurement protocol is reliable. Accuracy of CBCT measurements correlates with CAL gold standard measurements.

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Brently A. et al 2009

Compared the measurements from digital IR and CBVT images to direct surgical measurements for the evaluation of regenerative treatment outcomes.

Compared to direct surgical measurements,CBVT significantly more precise and accurate than IRs.

CBVT may obviate surgical reentry as a techniquefor assessing regenerative therapy outcomesWalter C et al..2011-

Suggests that cone-beam CT may provide detailed information about furcation involvements in patients with chronic periodontitis and so may influence treatment planning decisions

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MICRO CT

The term micro the pixel sizes of the cross-sections are in the micrometer range

.

Microtomography KNOW AS Industrial CT Scanninguses X-rays to create cross-sections of a 3D-object

Used in animal studies analysis of bone biopsies without destruction of samples

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Denta scan

DentaScan is a unique computer software program

provides computed tomographic (CT) imaging of the mandible and maxilla in three planes of reference: axial, panoramic, and oblique sagittal

.

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Uses

♣ visualization of internal bone morphology in three dimensions ; precise treatment planning

♣In cross sectional view, observation regarding bone quality, density can be made

♣ pre-operative planning of endosseous dental implants and subperiosteal implants

♣to visualize the bony structures pre-operatively

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Dentascan CT provides information of the internal structures that cannot even be gained by direct intra-operative visualization

the precise location of the mandibular canal

the location of the floor of the maxillary sinuses

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Dr Urvashi shah, Dr Subraya bhat

Utilization of denta-scan for treatment planing in patients with infra-bony defects

Infra-bony defects better visualized by denta-scan compared to intra-oral radiographs

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Computer program for assessing oral implant site

Uses raw data from CT along with advanced computer graphics

Advantages: • assessment of bone

volume, bone height &quality

• proper length of implant can be selected

• Clear visualization of inferior alveolar canal

SIMPLANT

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Digital tomosynthesis (DTS) Digital tomosynthesis (DTS) is a limited-angle tomographic

technique

only small rotation angles (a few tens of degrees) with a small number of discrete exposures are used.

provides some of the tomographic benefits of computed tomography (CT)

at reduced dose and cost

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K Ogawa et al 2010

Developed a new dental panoramic radiographic system

based on a tomosynthesis method

This system allowed the extraction of an optimum-quality panoramic image regardless of irregularities in patient position

the authors could freely reconstruct a fine image of arbitrary planes

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C Beda in 2010 proposed the Use of both DTS and CBCT reconstruction methods as an integrated solution for providing tomographic data in dental application

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OPTICAL COHERENCE TOMOGRAPHY Optical coherence tomography (OCT) is an

optical signal acquisition and processing method

an interferometric technique, employing near-infrared light. Layperson's explanation

“a technique for obtaining sub-surface images of translucent or opaque materials at a resolution equivalent to a low-power microscope.”

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OCT is well-suited for periodontal diagnosis

pocket morphology, and attachment level are digitally recorded

quantitative information of thickness and character of the gingiva, root surface irregularities, and the distribution of subgingival calculus

Otis L.L et. al. 2004

demonstrate the capacity of OCT to determine gingival thickness and the shape and contour of the alveolar crest.

Xiang et al. (2009)OCT imaging can offer three-dimensional imaging of periodontal soft tissues and bone at a very high resolution . Identify active periodontitis before significant alveolar bone loss occurs.

Reliable method for determining attachment level

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TACT-tuned aperture CT Based on the principles of

tomosynthesis

Low cost,low dose ,3D Imaging stystem

Series of radiographs taken from different angles

Soft ware (work bench) stacks the basic images and reconstruct in to multi planar images

Caries detection Vertical root fracture Helps to detect osseous defects around implants Detection and localization of osseous changes in

crestal bone

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Onanong Chai-U-Dom in 2002

Compared the potentials of conventional and TACT DSR detecting simulated bone-gain in periodontal defects, in vitro

TACT-DSR provide greater sensitivity and technique flexibility in detecting periodontal bone-gain than standard DSR.

Nair M K et al in 2002

Compared the diagnostic efficacy of tuned-aperture computed tomography (TACT) and conventional two-dimensional direct digital radiography (DDR) in an in vitro environment for detecting bone loss in mid-buccal and lingual crests.

TACT-IR performed significantly better than DDR

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SMALL VOLUME CT Form of CBCT

utilizes small field high resolution detector to generate high resolution 3D volume

Generally comparable to size of intraoral radiographs

van Daatselaar 2003 based on comparison made between a full CT geometry and a local CT geometry.

“local CT of dental structures appears to be a promising diagnostic instrument.”

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MRI Magnetic resonance imaging

does not involve the use of ionizing radiation

it involves the behaviour of protons in a magnetic field.

Hydrogen protons are used to create the MR image.

The image itself is another example of a

tomograph orsectional image that at first glance resembles a CT

Used for imaging intracranial and soft tissue lesions,

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The patient is placed within a very strong magnetic field (usually between 0.5–1.5 Tesla)

patient’s hydrogen protons, behaves like magnets to produce the net magnetization vector (NMV ) which aligns itself readily with the longaxis of the magnetic field

Radiowaves are pulsed into the patient by the

body coil transmitter at 90° to the magnetic field

Hydrogen atoms to resonate(store energy )

When radio frequency is turned off ,the stored energy is released from body and detected as a signal in a coil in scanner

Reconstruction of image

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USES IN HEAD AND NECK REGION

Assessment of intracranial lesions involving particularly the posterior cranial fossa, the pituitary and the spinal cord.

Investigation of the salivary glands

Tumour staging

Investigation of the TMJ to show both the bony and soft tissue components

Implant assessment

Schara et al 2009 In an invitro study evaluated the used the use of MRI to characterize inflammation and healing process in periodontal tissues

It was concluded that MRI can characterize the type and healing process of inflammation

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BONE SCANNING or RADIONUCLIDE

IMAGING

IN contrast to X-ray, CT, MRI which require structural or anatomic changes to be recorded,this technique assesses biochemical alteration in body

It Is a nuclear scanning test that identifies new areas of bone growth or breakdown.

It can be done to evaluate damage to the alveolar bones,and monitor conditions that can affect theperiodontium (including infection and trauma)

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radioactive tracer eg. 99m technetium pertechnetate substance is injected into a vein in the arm.

Areas that absorb little or no amount of tracer appear as dark or "cold" spots, which may indicate a lack of blood supply to the bone (bone infarction) or the presence of certain types of cancer

Areas of rapid bone growth or repair absorb increased amounts of the tracer and show up as bright or "hot" spots in the pictures. Hot spots may indicate the presence of a tumor, a fracture, or an infection.

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Other radioactive isotopes used are – iodine(131 I), gallium(67 Ga) & selenium(74Se)

γ scintillation camera is used to capture photons and then convereted to light and to voltage signal

Signal is constructed to planar image that shows radionuclide in the image

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Advanced nuclear imaging

• Single photon emission computed tomography

• Positron emission tomography

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Positive bone scans are detected in beagle dogs with advanced experimental periodontitis kaplan 1975 ,Jeffcoat et al 1985

Jeffcoat et al1985 –There exist a significant association with high intake of 99mTC and bone loss in moderate to severe periodontitis

Sensitivity of 83 % and specificty of 84 %

Reddy et al 1991 scintillation camera images following radiopharmaceutical administration is accurate in detecting bone loss

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IMPLANT IMAGING

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In 2000, the American Academy of Oral and Maxillofacial Radiology (AAOMR) recommended “some form of cross-sectionalimaging be used for implant cases “

conventional cross-sectional tomography be the method

2012

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PRINCIPLES OF IMAGING FOR

DENTAL-IMPLANT ASSESSMENT

Images should have appropriate diagnostic quality and not contain artifacts that compromise anatomic-structure assessments

Images should extend beyond the immediate area of interest to include areas that could be affected by implant placementsPractitioners should have appropriate training in operating radiographicequipment and competence in interpreting images from the modality used

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Initial examination

•PANORAMIC RADIOGRAPHY SHOULD BE USED AS AN IMAGING MODALITY

RECOMMENDATION 1

•USE IOPAs TO SUPPLEMENT PANORAMIC RADIOGRAPHY

RECOMMENATION 2

•DO NOT USE CROSS SECTIONAL IMAGING AS AN INITIAL DIAGNOSTIC AID

RECOMMENDATION 3

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Preoperative site specific imaging

•establish characteristics of residual alveolar bone

•determining orientation of RAR

•identifying local conditions restricting implant placement

• match imaging findings to the prosthetic plan

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RECOMENTATION 4cross sectional imaging of any potential implant site

RECOMENTATION 5CBCT considerd as the imaging modality of choice for imaging implant sites

RECOMMENDATION 6CBCT should be considered if need for augmentaion or other site development procedure is present

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Postoperative imaging

In the absence of clinical signs use IOPAS or

OPGs

Patient has mobility or

altered sensation use cross sectional

imaging /CBCT

Implant retrieval

CBCT

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DICOM StandardThe Digital Imaging and

Communications in Medicine

facilitate communications between imaging devices and systems.

By dictating specific data and interface requirements, DICOM ensure that devices--particularly devices made by different suppliers--can communicate with one another.

:

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Transmission and persistence of

complete objectsEg images,docs

Query and retrieval of

objects

Printing images on

film

Work flow managemen

t

Quality and consistency of

image apperance

DICOM address five primary areas of functionality:

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RADIOGRAPHS IN PERIODONTAL

DISEASE DIAGNOSIS &

MANAGEMENT

Features of periodontal diagnostic interest are

apparent on radiographs

Relationship exists b/w clinical attachment and

radiographic bone height

Radiographs can be used in all stages of

periodontal care

Tugnait et al 2000

Considered a provoking review

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EF CORBET, DKL HO, SML LAI 2009

Radiographs only inform with respect to diagnosis for a small proportion of periodontal conditions

Radiographs play a pivotal role is in treatment planing

Imaging approaches, such as cone-beam computed (digital volume) tomography,show some usefulness

Will probably remain a research tool without much clinical application

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Full-mouthsurveys of paralleling periapical radiographs have been considered to be a ‘‘gold standard’’ for periodontal diagnosis and treatment planning or

a panoramic radiograph supplemented by selected intra-oral radiographs , numbered less than four per patient reach the ‘‘gold standard’

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EXPOSURE FROM X RAYS

IOPA F speed ,rectangular collimator- 0.001mSV

IOPA E speed round collimator --.004mSV

Full mouth .080mSV

Panoramic .009 mSv

Cone Beam .068 mSv

Hospital CT 0.6 mSv

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Radiography must not be a substitute for clinical investigation

X-rays as a component of periodic examinations cannot be condoned.

Radiographic examination in clinical periodontology is only justified if changes in treatment plans from those treatment plans developed on the basis of clinical examination supplemented by any already available radiographs are anticipated

TO CONCLUDE…….

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Advanced imaging systems like CTs,CBCTs,have enabled better visualization of periodontal structures and pathologies in3D thus helping in better diagnosis and treatment planning

The cost factor and other technical difficulties have limited their cliniclal utility but their utility as a research tool is unquestionable

FURTHER IMPROVEMENT S ARE WARRANTED IN FIELD OF DIGITAL IMAGING And in near future these imaging techniques will become routine diagnostic tools

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THANK YOU