Simplified Positioning for Dental Radiology

1 Simplified Positioning for DentalRadiologyPrepared by:Animal Dental CareTony M. Woodward DVM, Dipl. AVDC5520 N. Nevada Ave. Suite 150 Colorado Springs, CO 80918(719) Radiology CHEAT SHEET Area imagedGeneral Technique and TipsLower PM andMPlace film in vestibule between the tongue and teeth. The beam isangled perpendicular to film. This is the only parallel technique Lower incisors+/- CaninesStart by aiming beam on ventral midline perpendicular to the tip the tube head forward 20 degrees so the beam is angled 20degrees caudally. If desired, using larger film will allowvisualization of the lower canines on the same incisorsStart by aiming beam on the dorsal midline, perpendicular to thefilm.

2 Then tip the tube head forward so the beam is angled 20degrees caninesStart by aiming beam dorsally over the top of the canine, similar tothe upper incisor view. Then tip the tube head 20 degrees forwardand 20 degrees to the side. This will move the image of the rootaway from the premolars. The film should slightly overlap the tipof the crown forward and to the Excessive film sticking out ofthe mouth is wasted. The forward tipping elongates the tooth, whilethe lateral tipping serves to move the canine tooth away from theoverlapping PM andMPlace the film mostly over the palate. Start dorsally over the top ofthe target teeth.

3 Tip the tube head 45 degrees to the side of the require a modified technique to avoid superimposition of theZygomatic Arch. The film is placed diagonally across the mouthfrom the inside of the maxillary teeth on the side opposite that to beimaged, to the inside of the mandibular teeth on the side to beimaged. Position the patient so that the target teeth are on top andthe teeth line up parallel to the table top. Start the beam lateral tothe maxillary premolars, and tip the tube head 20 degrees over thetop of the nose. Tipping too little cuts off part of the target teethfrom the edge of the film. Tipping too far accentuates theZygomatic Arch.

4 Three Simple Rules All Positioning errors involve the three parameters of tube angulation, tubeposition and film position. Three simple rules serve to identify and correctany If the image is foreshortened or elongated, adjust the tube angle. Tomake the roots longer, move the tube head more If you cut the target off at the edge of the beam (cone cut), simplymove the beam over toward the area of cone If you cut the target off at the edge of the film, move the film overtoward the area you cut following pictures show film placement, starting position of the beam and appropriate tipping of thebeam to image the five different areas of the mouth.

5 These diagrams are best used in conjunction withthe Positioning Cheat Sheet above. When performed as indicated, these simple Positioning guidelineswill provide well-positioned Dental for mandibular premolars and molarsLateral view showing film placementFront view showing tube positionPositioning for mandibular incisors and canines1. Front view showing filmplacement2. Side view showing thestarting position of the beam,pointed directly at the The tube head is then tipped20 degrees forward (beam isnow angled slightly caudally) Positioning for maxillary incisors1. Front view showing Side view showing thestarting position of the beam,pointed directly at the The tube head is then tipped20 degrees forward (beam isnow angled slightly caudally)4 Positioning for maxillary canines1.

6 Side view of initial film and tube positions. Notethat the beam is centered directly over the targettooth and is also perpendicular to the The tube head is first tipped 20 degreesforward, similar to the upper incisor view. Thistipping makes the image of the canine Front view after the tube head is tipped forwardin step # The tube head is then tipped 20 degrees to theside. This moves the canine tooth away from thepremolars, preventing for maxillary premolars / molars1. Film placement across thepalate. Here the tube ispositioned directly over the topof the maxillary premolars2. Here the tube is positioneddirectly to the side of themaxillary Splitting the differencebetween position #1 and #2 givesthe correct beam angle of for feline maxillary premolars and molars, using the near parallel technique 1.

7 Front view of film placement forimaging the right maxillarypremolars/molar in feline Side view of correct filmplacement. The maxillarypremolars will be visible nearthe edge of the View of filmplacement in an Patient in lateral recumbency. Thearcade to be imaged is away from thetable and parallel to the table top. Thebeam is started sideways to the teethto be The tube head is then tippedapproximately 20 degrees overthe top of the for feline maxillary premolars and molars, using an extraoral techniqueFront view showing the film placement and beamangle for the extraoral techniquePositioning for the extraoral technique, shownfrom the perspective of the X-ray beam6 Beam angulation used to separate overlying (posterior) obliqueLateralRostral (anterior) obliqu