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1、Extraoral Radiography Used for Panoramic,Lateral Jaw,Cephalometric,Skull and TMJ views,X-ray MachineIntraoral may be used for extraoral films but not recommendedPan/Ceph standard for ortho,oral surgeryExtraoral/Specialty rotating anode;because of high mA,long exposure,Intraoral,Pan/Ceph,Specialty Ex
2、traoral,Head Positioner/Film Holder,cassette holder,head positioner,Cassette/Film,Extraoral Film T-Mat(G,L,H)Ektavision5”x 12”,6”x 12”,8”x 10”,grid,primary x-rays,scatter radiation,film,Grid,intraoral,central ray enters 2”above,”behind EAM,Transcranial TMJ,Identify changes in TMJ region,red arrow=he
3、ad of condyleblack arrow=glenoid fossa,Lateral Cephalometric,Identify trauma,abnormalitiesAssess facial growth;treatment record,film at set distance from MSP,film horizontal,extraoral x-ray unit,MSP,floor,MSP,Simpson,Homer 12/2/02,Posteroanterior(PA)Skull,Identify trauma,pathology,ordevelopmental ab
4、normalities,FP,floor,MSP,extraoral x-ray unit,Taken with intraoral x-ray machine.(Note round collimation).Not recommended,but possible.,Waters,Evaluate the maxillary sinus,MSP,floor,extraoral x-ray unit,(Sinus view),tip of nose 1”from cassette,CR,FP,Submentovertex,Identify location of condylesImage
5、zygomatic arch fracture,floor,MSP,extraoral x-ray unit,floor,FP,central ray,Reduce exposure to 1/3 SV setting,Zygomatic Arch View,Reverse Townes,Image fractures of the condylar neck,head tipped down mouth open,extraoral x-ray unit,floor,MSP,CR,FP,Caldwell,Identify trauma,especially to area of orbit,
6、extraoral x-ray unit,floor,(Orbit view),tip of nose and chineven with cassette,MSP,CR,FP,Tomography(Laminography),Used to image TMJ X-ray procedure Images layer or slice Objects outside slice are blurred,Linear Tomography,Corrected Tomography,Linear,Linear,Multi-directional,Transcranial,Panoramic Fi
7、lm(special computer positioning),Computed TomographyX-ray procedure2.Section or slice imaged 360-degree rotation of x-rays/detectors Radiation/detector/computer/image,(CT),Computed Tomography,x-ray source,360 rotation,detectors,Computed Tomography,Fan beam,x-ray tube,collimator,detectors,Able to ima
8、ge soft tissue without contrast agents,Magnetic Resonance,Magnetic field aligns atoms(Hydrogen)Radiowaves alter alignment Atoms realign,releasing energy Computer produces image,NO IONIZING RADIATION,0,Magnetic Resonance,radiofrequency coils,Magnet,sliding table,ArthrographyRadiopaque contrast agent
9、injected into joint2.Articular disk outlined3.X-ray procedure(fluoroscopy,tomography),TMJ Imaging,MRI No Yes Arthrography Yes Yes CT Yes Yes Tomography Yes No Transcranial Yes No Panoramic Yes No,X-ray Disk,Sialography X-ray procedure2.Radiopaque contrast agent3.Images salivary glands and ducts,Scin
10、tigraphy(Radionuclide Scan)Radioactive pharmaceutical agent2.Tissue specificity3.Gamma rays emitted4.Gamma camera image,UltrasoundHigh-frequency ultrasonic vibrations2.Echoes at tissue density differences3.Varying echo intensities image NO IONIZING RADIATION,Ultrasound echoes,Cone Beam CT,Cone-shape
11、d x-ray beam360-degree rotation around headScan time around 20 seconds2D or 3D imagesPatient exposure=AFM$170K-300K;$30K yearly upkeep,Cone Beam CT,flat-panel detector,tubehead,0,0,0,0,0,0,X-ray machine Sensor Computer Monitor Printer,Digital Radiography,X-ray Machine Low kVp(70),mA(5)Accurate timer
12、 Small focal spot DC circuit Underexposure Graininess,Sensors CCD:Charged Coupled Device CMOS:Complimentary Metal Oxide Semiconductor Real Time Imaging(Direct)Wired(most common)or wireless,Image Receptors,0,Pros“Instant”image Better resolution More durable Cons Rigid and thick(3 to 8 mm)Expensive($5
13、,000 to$14,000)Most have wire connecting sensor to computer,CCD,CMOS,Plates PSP:Photo-stimulable Phosphor Laser scan(Indirect)Requires reduced lighting when scanning sensor plates Images erased by exposure to light before reusing plate,Image Receptors,PSP,PSP:Photostimulable Phosphor,Pros Patient fr
14、iendly;no change in technique More film sizes to choose from Plates relatively inexpensive($35+)Wider exposure latitudeCons Easily damaged More time consuming(laser scan)Less resolution,0,Use paralleling,bisecting angle or bitewing technique.Biteblocks are different for the direct sensors,but rest o
15、f instrument is the same.,0,Biteblocks for CCD,CMOS,Regular Rinn instruments for PSP,Both Direct and Indirect digital systems have panoramic and cephalometric applications.The direct is much more expensive.,Computer,2+GHz Pentium 4 with 256 MB RAMLarge storage capacity hard drive Periapical=300-400
16、KB Pan/ceph=4-7 MBCD/DVD writerLaptop optional,Monitor,CRT for radiographic interpretationLCD flat panel for patient presentation Best for color,such as photos Contrast ratio of 400:1 Dpi less than 0.27 mm,Printer,Diagnosis made on monitorGood quality ink jet or dye sublimationPhoto quality paper,Di
17、gital Radiography Advantages Reduced patient exposure(60-90%)Ability to enhance image Improved patient education“Instant”image(CCD,CMOS)Better workflow(CCD,CMOS),Digital Radiography Advantages Environmentally friendly(no lead,silver)No darkroom errors Improved archival quality of images Easier trans
18、fer of information,(continued),Cost comparisonNew practice:digital cheaperOngoing costs:digital cheaperCCD/CMOS system cheaper than PSP when buying only one sensorCheck warranty costs,Practice Management SoftwareMost systems compatible but check to make sure DICOM compliant digital software;better d
19、igital image management and sharing of information,Application Service ProviderStore images on Internet siteSmall monthly service fee“Chat”rooms(password protected),ScannersArchive current filmsManipulate digital image of films to“recover”informationSend information to insurance carrierCase presenta
20、tionsProbably not worth time/cost,Select series for patient,Full mouth series.Red rectangle highlights selected film,Magnified image,Adjust brightness,contrast,contrast,brightness,“Flashlight”feature,Measuring curved root,Colorization,Reverse black and white,Notes(problem,cost,etc.),Tooth#4 has Comb
21、o perio/endo involvement.Crack noted in apical third of tooth.Removal of#4 indicated,to be followed by new bridge or implants.,Combining intraoral/radiograhic,Lightyear,DEXIS ShareStation,Schick Wireless,Digital extraoral images,Magnification of image in selected area of pan,Digital Subtraction Radiography,THE END,
