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Welcome !. 1. Dental anatomy and Imaging With Eriks Oct 2012. 2. Dental Anatomy. General naming of teeth: Tip: Views always look into the patients mouth (not your own). Maxillar (Upper). Mandibular (Lower). 3. Dental Anatomy. “Directions”:. 4. Dental Anatomy.
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Dental anatomy and Imaging With Eriks Oct 2012 2
Dental Anatomy General naming of teeth: Tip: Views always look into the patients mouth (not your own). Maxillar (Upper) Mandibular (Lower) 3
Dental Anatomy “Directions”: 4
Dental Anatomy Tooth numbering: Always look into the patients mouth (not your own). ADA System: International System: Kids (1st set of teeth) have there own “numbering” with letters ! 5
Intraoral imaging: Periapical image: Health of teeth, roots, bone. Interproximal decay (caries) Bitewing:(interproximal) 7
Intraoral imaging: Occlusal image: exploring calcifications of the sublingual salivary glands. 8
Magnification Intraoral imaging technique: • Equal image enlargement • Caused by long object-sensor distance and short source-object distance • Minimized by controlling distance factors & focal spot
Shape Distortion Intraoral imaging technique: • Variation of the true shape of the object • Vertical distortion results in elongation foreshortening or • Horizontal distortion results in image widening and overlapping
Assembled Instruments • Anterior PA views • right and left • maxillary and mandibular • Bitewing views • right and left • Posterior PA views • right and left • maxillary and mandibular
Paralleling Periapical Technique • Applies most rules of accurate image formation • Most accurate periapical technique • Preferred technique for periapical imaging
Bitewing Technique Intraoral imaging technique: • Applies principles of paralleling technique to imaging the teeth crowns • Used to record interproximals • Most accurate view of the crowns and bony margins
Vertical Angulation (with tabs) When the film is positioned in the mouth, the upper portion of the film is angled approximately +20° as it contacts the palate. In the mandible, the film is upright (0° angle). The average between these two angles is +10°. This +10° is the vertical angulation selected when using bitewing tabs. +20º 0º
Bisecting Angle Periapical Technique Intraoral imaging technique: • Applies one of the rules for accurate image formation • Angle is formed by sensor and object • Produces images with shape distortion and magnification
Intraoral imaging technique: FMX (Full Mouth X-Ray) obsolete!
FMX Not to be confused with (although you might need dental a FMX after this):
Placement Errors Foreshortening • Short image from too much vertical angulation • Correction - place receptor parallel to tooth long axes and reduce the vertical angle
Placement Errors Elongation • Long image from not enough vertical angulation • Correction - place receptor parallel to tooth long axes and increase the vertical angle
Placement Errors Horizontal Overlap • Teeth widening and overlapped contacts from diagonal entry of the x-ray beam • To correct, place receptor parallel to horizontal plane, direct beam through • proximal contacts
Placement Errors Cone Cut • Zone of non-exposure from not centering x-ray beam over receptor • To correct, direct central ray through entry point and to the center of the receptor
Placement Errors Positioning Error • Receptor not placed in proper position to cover desired structures • Use receptor placement guidelines
Exposure Error • System will correct for most over or underexposures • Overexposure – exposure factors set too high • Underexposure – exposure factors set too low
Digital Pan Landmarks & Positioning Errors Spine Eye Socket Outline of Ear TMJ Nasal fossa/Airways Sinus Sinus Septum Eagles Mandibularcanal Necklace shadow Hyoid bone Mandibular canal Mental foramen Calcification of carotid Patient demonstrates too much smile – chin is positioned too far down
T h e D e n t a l C o m p a n y ORTHOPHOS XG 3D Ready 2D PROGRAMS P1…Panoramic P1A…Artifact Reduced P1C…25% Magnification & Special Needs Upper - Lower Right - Left P2 =Dentition – P2A Artifact Reduced – P2C Constant Magnification also for Compromised Patients P12…Anterior Views P10…Pediatric BW1…Bitewing View BW2 Lower Upper TM1…Lateral TMJOpen / Closed MS1…Slices(molar region) S1…Sinus Frontal 4 Sinus views 6 TMJ views offered
T h e D e n t a l C o m p a n y ORTHOPHOS XG 3D Ready 2D PROGRAMS General Information – Cover all patient contact surfaces with hygienic covers Patient must remove: Glasses All jewelry above the neck, to include earrings, necklaces, metal hair pins All removable appliances in the mouth that are removable Easy Patient Positioning (select appropriate bite piece, contact segment, or chin rest) Tap on P1, P1A, P1C To access sub programs Easy Pad Assists with Correct Selections Tap to Scroll through programs () (+) touch pad
T h e D e n t a l C o m p a n y ORTHOPHOS XG 3D Ready 2D PROGRAMS • Review: • Workstation • Select patient from Worklist or Register patient in SIDEXIS • Select PAN GREEN flashing light indicates Ready • Digital Pan • On LCD Screen Select Program – Patient Type, Etc. • Position Patient (if using lead apron solid is to back) • Use light to make certain Mid and Frankfurt correct • Remind Patient to swallow, place and keep tongue at • Roof of mount, and keep lips closed during digital • Image taking. • Remote Exposure Station – Confirm Selections • Press and hold to initiate exposure 14 sec. until • you hear (3) beep-beep-beep sound the • procedure is complete and unit is at rest • Digital Pan LCD Display • Shows snapshot of image - tap screen to remove image • Send image to PACS
Patient Positioning Devices One Piece Yellow Bite Block and Contact Segment – For Panoramic Images Bite Block Contact Segment Patients with anterior front teeth anterior teeth in groove Patients with missing anterior teeth Position under nose with cotton roll or 4x4 for space relationship Chin Rest – for patients with stability issues Patients with anterior front teeth Patients with missing front teeth
Patient Positioning Devices -Continued TMJ Programs TMJ Images Panoramic Forehead and Temple Supports Red Frankfurt and Mid Sagittal Light Lines
TMJ Head Positioner and Stabilizer TMJ Lateral - Medial open closed open closed Medial Medial Lateral Lateral TM 1.1 TM 1.2 TM 1.2 TM 1.1
Positioning Errors Patient Tilted AIR (to remove have patient swallow just before image is taken) Hyoid shadow Hyoid shadow
Pan with Necklace shadow and too much smile
Poor Patient Positioning plus artifacts Lead blocker– does this office use a Lead Apron? OR was this patient In a wheelchair with metal bar on headrest? Necklace shadow
Metal around Neck causes ARTIFACT Patient with Metal around neck (like necklace) causes artifact on image Always have patient remove necklace that lays above C7/T1 vertebra. Wrong = Interferes with beam Right = L
Cephalometric image Lateral Full Skull Ceph View with Landmarks Pterygomaxillary Fissure Sella Turcia Nasion Orbital Porion Anterior Nasal Spine Subspinale Basion Pogonion SIDEXIS XG