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1 2016 course three self-study course The Ohio State University College of Dentistry is a recognized provider for ADA CERP credit. ADA CERP is a service of the American Dental Association to assist dental professionals in identifying quality providers of continuing dental education. ADA CERP does not approve or endorse individual courses or instructors, nor does it imply acceptance of credit hours by boards of dentistry. Concerns or complaints about a CE provider may be directed to the provider or to the Commission for Continuing Education Provider Recognition at contact us phone toll free fax smsosu@osu.edu web dentistry.osu.edu/sms ABOUT this COURSE READ the MATERIALS. Read and review the course materials. COMPLETE the TEST. Answer the eight question test. A total of 6/8 questions must be answered correctly for credit. SUBMIT the ANSWER FORM ONLINE. You MUST submit your answers ONLINE at: RECORD or PRINT THE CONFIRMATION ID This unique ID is displayed upon successful submission of your answer form. ABOUT your FREE CE TWO CREDIT HOURS are issued for successful completion of this selfstudy course for the OSDB biennium totals. CERTIFICATE of COMPLETION is used to document your CE credit and is mailed to your office. ALLOW 2 WEEKS for processing and mailing of your certificate. The Ohio State University College of Dentistry is an American Dental Association (ADA) Continuing Education Recognized Provider (CERP). The Ohio State University College of Dentistry is approved by the Ohio State Dental Board as a permanent sponsor of continuing dental education. This continuing education activity has been planned and implemented in accordance with the standards of the ADA Continuing Education Recognition Program (ADA CERP) through joint efforts between The Ohio State University College of Dentistry Office of Continuing Dental Education and the Sterilization Monitoring Service (SMS). FREQUENTLY asked QUESTIONS Q: Who can earn FREE CE credits? A: EVERYONE - All dental professionals in your office may earn free CE credits. Each person must read the course materials and submit an online answer form independently. Q: What if I did not receive a confirmation ID? A: Once you have fully completed your answer form and click submit you will be directed to a page with a unique confirmation ID. Q: Where can I find my SMS number? A: Your SMS number can be found in the upper right hand corner of your monthly reports, or, imprinted on the back of your test envelopes. The SMS number is the account number for your office only, and is the same for everyone in the office. Q: How often are these courses available? A: FOUR TIMES PER YEAR (8 CE credits). Page 1

2 2016 course three Panoramic Techniques and Technique Errors Learning Objectives: 1. List the advantages and disadvantages of panoramic radiography when compared to intraoral radiography. 2. Describe the concepts of panoramic radiography and how the focal trough is developed and influenced by tubehead movement. 3. List the steps to be followed in properly positioning a patient for panoramic radiography. 4. Identify the common errors seen on panoramic films and explain how to correct these errors. 5. Test his or her knowledge by reviewing the True or False Questions This is a OSDB Category B Supervised self-instruction course. INTRODUCTION written by Constance R. Kuntupis, RDH, MA edited by Ross White, BS Jon Strasbourg, BA release date August 1, 2016 (7:30 AM EST) The purpose of this CE self-study is to review Panoramic Radiography advantages and disadvantages, describe the concepts of panoramic radiography and how the focal trough is developed and influenced by tubehead movement. This CE self-study will also address problems commonly associated with panoramic technique and provide solutions for properly positioning a patient for panoramic radiography. This course will focus on common errors that are often seen on the panoramic image which decrease the diagnostic quality and provide solutions on how to correct these errors. last day to take the course at no charge August 31, 2016 (4:00 PM EST) last day course is available for credit December 31, 2018 Page 2

3 Panoramic Imaging Indications for Panoramic Imaging Evaluate trauma, pathology and third molar location Temporomandibular joint (TMJ) pain Mixed dentition analysis, retained teeth or root tips in edentulous areas Evaluate developmental anomalies Panoramic Concepts As the panoramic x-ray tubehead rotates around the patient, the image is recorded on the image receptor in vertical segments which are restricted by the narrow beam and collimation. The panoramic has much more narrow beam than the round-collimated beam used in intraoral radiography. Periapical and Bite-Wing Intraoral Imaging techniques are preferred over Panoramic Imaging for: Caries Periodontal involvement Periapical pathology (pain, fistula) Root canal therapy Advantages of Panoramic Radiography Larger anatomical area covered Less patient exposure than from a full series of intraoral images Ease of operation Patient cooperation Disadvantages of Panoramic Radiography Decreased sharpness of the image compared to intraoral images High cost of equipment compared to intraoral x- ray units Objects outside focal trough may not be seen on the image Left Image: Panoramic Image Rotation Center Right Image: Periapical Image The receptor and tubehead rotate around the patient, exposing different parts of the receptor as the x-ray beam passes through different parts of the patient s head. The center of rotation changes as the tubehead rotates around the patient. This changing or sliding rotation center determines the shape and size of the image layer or focal trough. Page 3

4 Rotation Center, Continued... Tubehead angled upward Focal Trough Rotation center Receptor Cassette shield The focal trough will vary in shape depending upon the manufacturer of the Panoramic machine, however the invisible area is a threedimensional curved zone between the source of radiation and the image receptor. When positioning the patient, the operator must be sure that the patient s dentition and related structures fall within this three-dimensional curved zone for the least amount of distortion and yield the most diagnostic value. All images of the objects radiographed will be magnified, however if the patient is positioned properly, the objects are magnified uniformly in both horizontal and vertical dimensions. Panoramic images magnify the objects by 20-30% horizontal and vertical as compared to the structures actual size. 1. Front to-back (anterior posterior) Red arrow 2. Side-to-side (Bucolingual) Green arrows 3.Up-and-down (Vertical) Purple arrow Focal Trough, continued Objects located outside the focal trough are blurred so that they are not seen on the image. However, if an object is dense enough (such as metal) it will show up on the panoramic image. The patient should be positioned according to the manufacturer s recommendations and asked to remove glasses, jewelry or other metallic items in the head or neck region. If metal is left on the patient in the head or neck region, a secondary image will be produced on the panoramic image called a Ghost Image. The ghost image appears on the opposite side of the panoramic image. For example, if a patient has an earring in the left ear, the actual image of the earring will appear on the patient s right side on the panoramic image. The ghost image will be less distinct, will appear larger and is projected higher in the panoramic image. Panoramic Technique There are many different types of high-quality film-based and digital panoramic machines available. However, the basic positioning of the patient is the same for each machine. Before setting up the patient (and if using film it must be loaded), a bite-stick cover must be placed, and any necessary adjustments must be made to the machine. The patient is instructed to remove all jewelry, dentures or appliances, hair ornaments, etc. After raising or lowering the machine to the proper height for the patient, the patient is positioned as follows: The patient is instructed to place the front teeth in the notch of the bitestick. This positions the front teeth in the focal trough. Make sure the midsagittal plane is centered. (The midsagittal plane is centered by a line drawn from the center of the chin through the tip of the nose). Adjust the tilt of the head until the Frankfort Plane is parallel to the floor. The Frankfort Plane is represented by a line drawn from the top of the ear canal to the bottom of the eye socket). Page 4

5 Midsagittal Plane Panoramic Technique Errors Teeth Too Anterior Frankfort Plane Problem: The teeth are positioned in front of the notches in the bitestick. Make sure the patient is standing very straight (No slouching). Correct Incorrect Result: If the teeth are in front of the notches, they are closer to the image receptor and will appear narrower, resulting in less magnification horizontally (narrowing). The anterior teeth will appear narrower and be blurred because being outside of the focal trough makes the images less sharp. Patient standing upright with spinal column straight Patient slouching Set correct exposure factors. Exposure factors will vary depending on the machine and the size of the patient. Check your manufacturer s recommendations. Advise patient to swallow to feel tongue contact palate. Tell patient to maintain this contact entire time of exposure (20 seconds). Depress exposure button and hold down until the machine completes its rotation. Helpful hint : you can t go wrong by holding button too long Depress exposure button until all sound and movement of the machine has ended. Page 5

6 . Teeth Too Posterior Problem: The teeth are positioned behind the notches in the bitestick. Head Turned Problem: Patient s head is turned slightly to the side. Teeth are not centered on the bitestick. Result: The anterior teeth will appear wider and will be blurred (less sharp than normal). If the teeth are behind the notches, they are farther from the image receptor, resulting in more magnification horizontally (widening). Being out of the focal trough makes the images less sharp. Result: The teeth are smaller on the side to which the head is turned. (When the teeth are closer to the film, there is less magnification horizontally). The teeth that are farther from the film are wider because there is increased magnification horizontally. Question: On this radiographic image, not only are the teeth wider on one side, but the ramus is also wider on that side. (The black arrows are the same length on both sides). Which side was farthest from the image receptor? Page 6

7 Answer: The patient s right side is farther away from the image receptor, therefore causing more magnification of the patient s right side. Head Tipped Down, continued Notice how short the mandibular incisors appear. The rest of the teeth are relatively normal. Head Tipped Down Problem: If the head is positioned so that the Frankfort Plane is inclined downward. Head Tipped Up Result: The mandibular incisors will appear shortened and the mandible will be V- shaped. This particular panorex has the appearance of an exaggerated smile or a laugh-like appearance. Problem: If the Frankfort Plane is angled upward, the mandible will be squared-off (angle of the mandible approximately 90 degrees). Result: The hard palate will be superimposed over the roots of the maxillary teeth. This panorex may have the appearance of a reverse smile or a broad flat mandible. Page 7

8 Head Tipped Up, continued Result: In the radiographic image below, the hard palate (red arrows) is covering the roots of the maxillary teeth. Note the reverse smile. Lead Apron Artifact The panoramic image below shows an extensive white area caused by the lead apron. Note the black dots (arrows) that represent the stitching on the lead apron. The thyroid collar should never be used for panoramic radiography since it would routinely cause this same problem. You cannot see any anatomy in these areas due to complete blockage of the x-ray beam by the apron. Lead Apron Problem: The lead apron is improperly positioned so that it is located high on the back of the patient s neck. Result: If the lead apron is too high on the back on the patient s neck, it may block part of the beam and result in a clear area in the lower center area of the panorex. Cervical Vertebrae (Spine) Problem: The patient is not standing straight. The patient may be slouched or the patient may have osteoporosis. Result: The cervical vertebrae may block the x-ray beam as the tubehead travels behind the patient at an upward angle. This results in a radiopaque area that extends up through the middle of the film (arrows below). The teeth/bone are faintly visible in the radiopaque area (not completely blocked out as with the lead apron). Lead Apron Shadow Page 8

9 Cervical Vertebrae (Spine), continued This panoramic image shows the radiopaque shadow caused by the cervical vertebrae in a patient that is not standing straight. Note that the edges of this radiopaque area are not as sharp as those produced by the lead apron; here the radiopacity blends in with the surrounding bone. Palatoglossal Air Space, continued The red arrows in the panoramic image below identify the palatoglossal air space. Failure to Remove Appliances Palatoglossal Air Space Problem: Many patients have difficulty and fail to comply with the instructions to keep the tongue against the palate during exposure. Result: The Palatoglossal Air Space is a dark air space which is superimposed over the apicies of the maxillary teeth on a panoramic image. This air space is caused by failure to keep the tongue against the palate during exposure. This makes it difficult to diagnose periapical pathology because it is also dark in the maxillary area. Problem: As part of patient preparation, removable metal appliances should be removed from the patient s mouth. Result: Both upper and lower removable partial dentures were left in the mouth. In this case the metal frameworks obscure large areas of the teeth and the film should be retaken. Failure to Remove Appliances, continued Result: In this patient, the complete upper denture was left in the mouth. This would not require a retake, since the acrylic of the denture base allows x-rays to pass through and the bone is clearly visible. Page 9

10 Failure to Remove Tongue Ring Problem: Anything removable in the mouth should be taken out before exposing a panoramic film. Result: In this patient, a tongue ring was left in place and blocks a couple of teeth. Question: What other error is evident on this film? Answer: The head is tipped up too much. Notice the reverse smile and the proximity of the hard palate to the roots of the maxillary teeth. Ghost Images Problem: Failure to remove objects such as jewelry. Question: Does the tongue ring need to be removed for intraoral periapical films? Result: As the x-ray beam passes around the patient, objects such as jewelry or dense bone will produce a real image on the side where the object is located and a ghost image on the opposite side. This ghost image will have the same shape and orientation as the real image, but it will be larger and projected higher on the film and will be very blurred. Answer: No. The tongue ring would be behind the receptor and would not cause a problem, assuming normal film placement. Glasses Problem: Glasses should routinely be removed for panoramic exposures. Result: The bottom part of the frame/lenses may obscure the periapical area of the maxillary anterior teeth. Page 10

11 Ghost Images, continued Ghost Images of hoop earrings. The ghost image (see a-g below) has the same shape and orientation, but is higher, larger and on the opposite side when compared to the image of the actual object (see a below). This film shows excessive patient movement (unknown cause) and must be retaken. a-g Incorrect Exposure Settings Patient Movement Problem: It is important for the patient to remain still during a panoramic exposure. Result: This film shows much more subtle movement (red arrow below), resulting in an uneven inferior border of the mandible. This might be misinterpreted as being the result of a fracture. a Problem: Correct exposure factors must be selected for a patient. Result: If incorrect exposure factors are selected for a patient (kvp, ma), an image that is too light (underexposed) or too dark (overexposed) may result. Overexposure Underexposure Page 11

12 REFERENCES AND RESOURCES 1. White, Stuart C, and M J. Pharoah. Oral Radiology: Principles and Interpretation. St. Louis, Mo: Mosby/Elsevier, Successful Panoramic Radiography Edited by Birgit Junfin Glass, D.D.S., M.S. University of Texas Health Science Center Dental School San Antonio, TX EDUCATIONAL LINKS ABOUT THE AUTHOR CONSTANCE R. KUNTUPIS, RDH, MA ASSISTANT PROFESSOR OF CLINICAL DENTISTRY IN THE DEPARTMENT OF RADIOLOGY, AT THE OHIO STATE UNIVERSITY COLLEGE OF DENTISTRY. SHE RECEIVED HER BACHELOR OF ARTS DEGREE IN SECONDARY EDUCATION AND HER BACHELOR OF SCIENCE DEGREE IN DENTAL HYGIENE FROM WEST LIBERTY UNIVERSITY IN WEST VIRGINIA. AFTER SEVERAL YEARS OF CLINICAL EXPERIENCE AS A REGISTERED DENTAL HYGIENIST, MS. KUNTUPIS COMPLETED A MASTER OF ARTS DEGREE IN ADULT EDUCATION AND LIFELONG LEARNING AT THE OHIO STATE UNIVERSITY. AS A DENTAL HYGIENIST IN THE GENERAL PRACTICE RESIDENCY / ADVANCED GENERAL DENTISTRY CLINIC AT OSU FROM , MS. KUNTUPIS HAS SPECIALIZED IN PROVIDING CARE TO PATIENTS WITH SIGNIFICANT MEDICAL OR PHYSICAL DISABILITIES AND PATIENTS WITH SPECIAL NEEDS. MS. KUNTUPIS IS CURRENTLY AN ASSISTANT PROFESSOR OF CLINICAL DENTISTRY IN THE DEPARTMENT OF RADIOLOGY AT THE OHIO STATE COLLEGE OF DENTISTRY. SHE HAS COMPLETED NUMEROUS ORAL RADIOGRAPHY CONTINUING EDUCATION COURSES AND WORKSHOPS ACROSS THE COUNTRY AND HAS BEEN TEACHING ORAL RADIOGRAPHY TO DENTAL ALLIED HEALTH PROFESSIONALS FOR NEARLY 20 YEARS. MS. KUNTUPIS CAN BE REACHED AT KUNTUPIS.1@OSU.EDU NEITHER I NOR MY IMMEDIATE FAMILY HAVE ANY FINANCIAL INTERESTS THAT WOULD CREATE A CONFLICT OF INTEREST OR RESTRICT MY JUDGEMENT WITH REGARD TO THE CONTENT OF THIS COURSE Page 12

13 post-test instructions - answer each question ONLINE - press submit - record your confirmation id - deadline is August 31, 2016 (4:00 PM EST) 1 T F The rotation center is the zone where structures are clearly demonstrated on a panoramic radiograph 2 T F Only a thyroid collar is necessary when utilizing panoramic radiography 3 T F 4 T F When a patient is positioned too far back and the teeth are posterior to the notches in the bitestick, the anterior teeth will appear magnified and much wider than their actual size If the patient s head is turned then the teeth will appear much smaller on the side to which the head is turned 5 T F 6 T F 7 T F It is called a ghost image if air spaces occur creating a lack of detail or are completely missing on a panoramic digital image The Midsagittal plane is the name of the invisible line or vertical light that runs down the center of the patient s nasal cavity on the patient s midline The primary use of a panorex is to diagnose periodontal disease or caries at a patient s initial exam d i r e c t o r john r. kalmar, dmd, phd kalmar.7@osu.edu program manager ross white, bs white.1483@osu.edu channel coordinator jon strasbourg, ba strasbourg,.1@osu.edu 8 T F When the patient s head is tipped up too high, it causes the hard palate to be superimposed over the roots of the maxillary teeth creating a reverse smile or broad flat mandible Page 13