PANORAMIC Imaging Volume 1, Issue 1News $4.50US

Editor: How did this Newsletter get started? Allan G. Farman, B.D.S., PhD (odont.), D.Sc (odont.), By Dr. Allan G. Farman at this time. Diplomate of the American Board During the Chicago Midwinter meeting It is for this reason that I agreed to edit a of Oral and Maxillofacial earlier this year, I was asked by newsletter on panoramic that , Professor of Radiology representatives from Panoramic Corporation would be distributed as a service to the and Imaging Sciences, if I could recommend a good general dental profession. My agreement is Department of Surgical and contingent upon editorial independence, Hospital Dentistry, The University textbook on panoramic radiography. of Louisville School of Dentistry, Apparently there is a great deal of interest strict avoidance of commercial content, and Louisville, KY. within the dental profession in obtaining a focus on the interpretation of panoramic clinically relevant information on how to radiographs in general rather than achieve the maximum diagnostic yield from radiographs made using a machine from the panoramic radiograph. On my personal one particular vendor. Each issue will library shelf, I have several texts on contain three to five-and-a-half pages of Featured Article: panoramic radiography published by such content, mostly devoted to one topic in each case. There will also be selected Panoramic Interpretation eminent sources as Manson-Hing, Langlais and Chomenko; however, when I looked at clinically relevant abstracts from the the dates of publication inside the front scientific literature. The final half-to-one In the Recent Literature: covers of these books, I was disappointed page will be a user’s technical guide in Periodontal Disease to find that the latest revision was made which Panoramic Corporation staff provide more than a decade ago. A thorough useful tips and other information specific to Ridge Assessment search of the World Wide Web, including the Panoramic Corporation PC-1000. Osteoporosis “Bestbookbuys.com” showed that I was not Again, there will be no comparisons made mistaken in thinking that there is no between brands. The intent of this available text based upon modern Newsletter is to be a resource for the dental Developmental Anomalies panoramic technology. No easy-to-access, profession rather than an advertisement. up-to-date resource on panoramic You may wish to collect successive F.A.Q.’s: radiography exists in the English language Newsletters in a ring binder as a reference.

Light Films Dark Films Getting the most out of panoramic Anterior Whiteout radiographic interpretation. Quality assurance badly. Most errors are due to incorrect As with any other radiographic method, patient positioning, leading to excessive optimum interpretable diagnostic images and sometimes disproportionate distortion. can only be achieved with careful quality A correctly positioned patient’s panoramic assurance in patient positioning, in radiograph generally shows symmetry of selecting appropriate exposure parameters the size of the mandibular rami and Provided as a professional service by: and during processing. While panoramic condyles, and the dental segments are “in Panoramic Corporation radiography is easy to perform well focus” with a gentle downward convexity of [email protected] provided all the manufacturer’s instructions the maxillary archs. Provided the patient bit are followed, it is equally easy to perform correctly on the biteblock, the anterior

Panoramic Imaging News “You can sequence your evaluation in many ways; however, it is very important to develop a consistent approach that ensures that all diagnostic information in the radiograph is indeed read.”

structures are portrayed in the midline and Interpreting a normal the apices of the mandibular incisor teeth panoramic radiograph should be in full “focus.” Provided that the A normal panoramic radiograph contains a tongue is kept up in the roof of the mouth substantial amount of information. Figure 7 during exposure, the roots of the maxillary is the PC-1000 (Panoramic Corporation, teeth are clearly demonstrated. It is less Fort Wayne, Indiana) panoramic radiograph expensive in time and materials - and in of a 12-year male patient. Fifty distinct soft to the patient - to perfect your Fig.1. A panoramic radiograph simultaneously tissues, bony and dental landmarks have panoramic technique, than to make presents views from both sides of the patients face been labeled on this radiograph. When was as well as providing a frontal perspective. unnecessary repeat exposures. And the the last time that you consciously and diagnostic yield from an excellent thoroughly inspected all of the structures panoramic radiograph is far superior to one that are demonstrated? As you probably are made under less rigorous quality controls. making the radiograph with the intent of dental diagnosis at the forefront, the dental Image projection geometry arches should be left to last in your systematic evaluation of the image. You can To gain the maximum amount of diagnostic sequence your evaluation in many ways; information from a dental panoramic however, it is very important to develop a radiograph (pantomograph), it is necessary consistent approach that ensures that all to understand that panoramic radiographs diagnostic information in the radiograph is are “flattened out” schemes of a curved indeed read. To see all of the subtle image layer. Think of the plan view of the Fig. 2. You can best understand the relative position variations in contrast, it is imperative that of structures shown in a panoramic radiograph if you head (Fig. 1). The panoramic radiograph (1) a view box be used (preferably having imagine the film to be bent around the patients face. provides a plan of one side, then the a variable light intensity), (2) any midline, then the other side of the face and extraneous light from the view box be . Imagine the panoramic film wrapped blocked out, and (3) the diagnostic around the outside of the face. The actual evaluation is performed under subdued panoramic film seems large in comparison ambient lighting away from distractions. It with the 3M human phantom (Fig. 2). This is suggested that you review all panoramic is because the actual image from most radiographs made in a given day when all panoramic systems is enlarged by about patients have left the practice. It will be 20 %. Figures 3 and 4 show a printed Fig. 3. The lateral and more posterior structures are surprising how much can be gained from panoramic image reduced to life size projected to each side of the panoramic radiograph. such a second look when the atmosphere is superimposed on the phantom. These likely to be more relaxed! graphically explain the association between the panoramic radiograph and the represented structures. In reality the image I approach reading the radiograph roughly is formed section by section behind the in the numerical sequence shown in Figure secondary slit. Figure 5 illustrates this 7; namely starting with the bony landmarks process by putting the same printed from the midline of the upper and nasal panoramic image in place of the film cavity, then working back in the and cassette. The relative movement of the x-ray zygomatic complex on each side. The soft source and the “camera” during exposure tissue shadows of the tongue and soft creates the effect of “wrapping the film palate are incorporated at this stage. This is Fig. 4. The anterior structures are shown in the about the patient’s face” (Fig. 6). followed by evaluation of the cervical spine midline of the standard panoramic projection.

Panoramic Imaging News [email protected] Fig. 5. The panoramic image is formed sequentially from information passing through the machine’s secondary slit. The film moves past the secondary slit at the appropriate rate necessary to minimize mechanical distortion.

Fig. 6. The panoramic latent image is created as the film cassette moves past the secondary slit. The production of the latent image is simulated using the print of a panoramic radiograph.

Fig. 7. Annotated panoramic radiograph.

and associated structures. I then evaluate Anatomical Comparisons the contents of the starting from Using the same numerical key as that for the midline and then progressing posteriorly the annotated radiograph (Fig. 7), Figures 8 on each side. Any examination would be and 9 show the normal anatomical incomplete without a thorough evaluation of Fig. 8. Annotated lateral view of phantom. structures viewed from the lateral and frontal the soft tissues anterior to the spine and facial aspects of a 3M phantom. It should inferior to the mandible. [The evaluation of be remembered that the radiograph shows this space will be the main subject of the all features within the panoramic image next issue of this Newsletter.] The last part layer whether facial or lingual. It should of the evaluation should be the area of chief also be remembered that only the structures complaint and the dental arches. that are within the selected image layer will be in “focus.” This image layer is generally narrower for the anterior regions than for the posterior segments.

Fig. 9. Annotated anterior view of phantom.

1-800-654-2027 Key To Annotation of Panoramic Image In Figure 7

1. Nasal Septum 25. Mandibular Foramen and Lingula 2. Anterior Nasal Spine 26. Mandibular Canal 3. Inferior Turbinate 27. Mental Foramen 4. Middle Turbinate 28. Inferior Border of Mandible 5. Superior Turbinate 29. Hyoid 6. Soft Tissue Shadow of the Nose 30. Pharyngeal Airspace 7. Airspace between Soft Tissue 31. Epiglottis Shadow of Upper Border of 32. Coronoid Process of Mandible Tongue & Hard Palate 33. Inferior Orbital Rim 8. Lateral Wall of Nasal Passage 34. Mastoid Process 9. Maxillary Sinus (Antrum) 35. Middle Cranial Fossa 10. Nasolacrimal Canal Orifice 36. Biteblock for Patient Positioning 11. Orbit During Panoramic Radiography 12. Infraorbital Canal 37. Chin Holder (Cephalostat) 13. Zygomatic Process of the Maxilla 38. Shadow of Cervical Spine 14. Pterygomaxillary Fissure 39. Ethmoid Sinus 15. Maxillary Tuberosity with 40. Angle of Mandible Developing Third Permanent Molar 41. Crypt of Developing Mandibular Third Permanent Molar Tooth 16. Zygoma 42. Developing Mandibular Second 17. Zygomatico-Temporal Structure Premolar Tooth 18. Articular Eminence of Temporal 43. Primary Second Molar Tooth 19. Mandibular Condyle Showing Physiological Root 20. External Auditory Meatus Resorption 21. First Cervical Vertebra (Atlas) 44. Maxillary Permanent Central Incisor Tooth 22. Second Cervical Vertibra (Axis) 45. Maxillary Permanent Lateral 23. Third Cervical Vertebra Incisor Tooth 24. Fourth Cervical Vertebra 46. Maxillary Permanent Canine Tooth 47. Maxillary First Premolar Tooth 48. Maxillary Permanent First Molar Tooth 49. Ramus of Mandible 50. Pterygoid Plates

www.pancorp.com Panoramic Imaging News In The Recent Literature:

Periodontal disease: Panoramic d’Hoedt B, Behneke A, Behneke N. A The purpose of this case-control study radiography is the most frequently new method for the radiological was to determine whether the radiographic used x-ray method for assessment investigation of residual ridge resorption appearance of the mandibular cortical of periodontal disease at dental in the maxilla. Dentomaxillofac Radiol bone in elderly, noninstitutionalized schools in the UK and Ireland. 2000 Nov;29(6):368-75. [from the patients correlated with the history of Tugnait A, Clerehugh DV, Hirschmann Department of Oral Surgery, Johannes osteoporotic fractures. Patients older than PN. Survey of radiographic practices Gutenberg-University Mainz, Germany.] 60 years, and who had a panoramic for periodontal disease in UK and Irish radiograph were invited to be interviewed The authors present a new method for dental teaching hospitals. regarding their fracture history and risk assessing residual ridge resorption in the Dentomaxillofac Radiol 2000 factors for osteoporosis. The study edentulous maxilla. Defined experimental Nov;29(6):376-81. [from the population comprised 93 individuals and reference areas in the maxilla were Department of , Leeds reporting osteoporotic fractures (fractures drawn on transparent film laid over a Dental Institute, Leeds, UK.] occurring after minor impact). Controls (n panoramic radiograph and digitized. Bone = 394) were individuals reporting The objective of this paper was to assess areas were measured with an integrated current radiographic practices for the traumatic fractures (n = 105) or no planimetry program and expressed as a management of patients with periodontal fractures (n = 289). Blinded to case- ratio. The effect of positioning errors on disease. All dental teaching programs in control status, the investigators evaluated reliability of the method was investigated the UK and Ireland were sent a the mandibular cortex on a panoramic using dry . The correlation between questionnaire on radiographic equipment radiograph and classified them as normal the change in ratio and actual bone loss and radiograph selection currently used (even and sharp endosteal margin), was examined by progressively reducing for assessment of patients with destructive moderately eroded (evidence of lacunar the height of an artificial residual ridge on periodontal diseases. Opinions were resorption or endosteal cortical residues), one . The coefficient of variation for recorded for advantages and or severely eroded (unequivocal porosity). the absolute ratio in different head disadvantages of the most frequently used In addition, cortical thickness was positions was < 0.05 and its correlation radiographic views. A 100% response measured below the mental foramen. After coefficient of the change in the ratio and rate was achieved. All programs used adjustment for potentially confounding the degree of resorption was r2 ≥ 98.3% panoramic and specific periapical factors, the odds ratio for an osteoporotic radiographs as one of their radiographic (p = 0.0001). Comparison of the fracture associated with moderately regimes for patients with periodontal experimental area with the reference area eroded and severely eroded mandibular disease. Of the respondents, 53% most on serial panoramic radiographs appears cortices was 2.0 (95% Cortical Index 1.2 frequently made panoramic and selected suitable for the assessment of residual to 3.3) and 8.0 (95% Cortical Index 2.0 periapical radiographs, 24% made full ridge resorption in the maxilla. to 28.9), respectively. After adjusting for mouth periapical radiographic series Osteoporosis: Panoramic all potentially confounding factors, it was most often, and 18% took a panoramic radiographic evidence of thinning determined that the cortex was 0.54 mm radiograph alone. In conclusion, more of the mandibular cortex (or 12%) thinner in subjects with an than 70% of dental teaching programs in corresponds to a history of osteoporotic fracture compared with the UK and Ireland make panoramic osteoporotic fractures in patients controls (95% CI, 0.25 to 0.84 mm). radiographs, with or without selected older than 60 years. Patients with a history of osteoporotic periapicals, to assess periodontal status. Bollen AM, Taguchi A, Hujoel PP, fractures tend to have increased resorption Edentulous ridge assessment: Hollender LG. Case-control study on and thinning of the mandibular lower Laboratory data suggests that self-reported osteoporotic fractures and cortex that can be measured from serial panoramic radiographs mandibular cortical bone. Oral Surg Oral panoramic radiographs. are suitable for assessing the Med Oral Pathol Oral Radiol Endod Atherosclerosis: Patients progression of maxillary ridge 2000 Oct;90(4):518-24. [from evidencing calcifications resorption. Department of , University overlying the carotid region seen Kreisler M, Schulze R, Schalldach F, of Washington, Seattle, USA.] on panoramic radiography

Panoramic Imaging News should be referred to their calcium deposits overlying both carotid Radiology, Faculty of Dentistry, Chulalongkorn physician with a recommendation bifurcation regions on a panoramic University, Bangkok, Thailand.] of formal evaluation for potentially radiograph. Subsequent duplex ultrasonic Panoramic radiographs of 1,608 children life-threatening atheroma. examination indicated bilateral, high-grade and adolescents aged 10 to 15 years (797 Almog DM, Illig KA, Khin M, Green RM. carotid arterial stenoses. The patient had males and 811 females) were reviewed to Unrecognized carotid artery stenosis critical carotid arterial stenoses associated determine the prevalence of tooth and jaw discovered by calcifications on a with significant risk of that had not abnormalities. Abnormalities were detected panoramic radiograph. J Am Dent Assoc been identified otherwise. The findings on on 21% of the radiographs (23% for 2000 Nov;131(11):1593-7. [From the the panoramic radiograph led to females and 17% for males); 879 teeth Eastman Department of Dentistry, appropriate and potentially life-saving were diagnosed with abnormalities in 331 University of Rochester, New York, USA.] treatment. The patient underwent uneventful panoramic radiographs. The more common Approximately 730,000 occur each bilateral carotid endarterectomy. abnormalities were malpositioned teeth, year in the United States, costing an Developmental abnormalities: missing teeth, morphologic anomalies of estimated $40 billion annually. One-half of Abnormalities affecting dental teeth, and teeth with structural defects such all strokes are the result of atherosclerotic treatment planning were found in as hypoplasia. Bony abnormalities and plaques found in the carotid artery. Such panoramic radiographs from > 20% growth problems were detected on plaques frequently are heavily calcified and of adolescents aged 10-15 years. occasion. These findings demonstrates the can be identified on a panoramic Cholitgul W, Drummond BK. Jaw and tooth value of panoramic radiography in detecting radiograph by the incidental finding of abnormalities detected on panoramic or confirming dental abnormalities, and calcifications overlying the carotid radiographs in New Zealand children aged supports recommendations on the use of bifurcation. The authors found that a 67- 10-15 years. N Z Dent J 2000 panoramic radiography to aid in the year-old asymptomatic woman had Mar;96(423):10-3. [From the Department of assessment of dental development.

Frequently Asked Questions From Our Service Department: 1. Q: Why are we getting light films? 2. Q: What causes a dark film? 3. Q: How can we eliminate the whiteout A: Light films can be the result of any A: Dark films can be a result of in the anterior region of the film? one or combination of the following: any one or combination of the A: The white out in the anterior region * The intensifying screens could be following: is a result of patient positioning: reversed or turned inside out. * Light exposure from light leaks in First you want the patient to stand darkroom or daylight loader. as straight as possible, position the * The chemicals in the processor could patients feet under the chinrest, this be weak. * Light exposure from too great of will make sure the neck is straight, * The temperature in the processor safelight bulb wattage. next lower the machine so the could be low. * Safelight being mounted closer Frankfort Plane (imaginary line from * Developing time could be short than 4’ from work surface. the middle of the opening to the bottom of the eye orbit) is parallel to * Intensifying screens could be * Exposure from equipment with operational lights in the darkroom. the ground. This will help stretch worn out. the patient’s neck enough to allow * Tubehead is out of alignment * Processing temperature is set too high. X-rays to pass between the vertebrae * Processing time is set too long. in the neck, allowing radiation to * Incorrect type of film for the reach the anterior region of the film. intensifying screens being used. Provided as a professional service by:

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