Radiographic techniques

1. INTRAORAL RADIOGRAPHIC TECHNIQUES

2. Periapical Bitewing Occlusal RADIOGRAPHS

3. Periapical views are used to record the crowns, roots, and surrounding bone. Root canal treatment. Assessment of root formation n completion. Assessment of root morphology. Assessment of relationship of roots to various vital structures. Implant site assessment and placement. PERIAPICAL VIEW

4. Paralleling technique( right-angle or long-cone technique )

5. Principle : The central concept of the paralleling is that “the x-ray receptor is supported parallel to the long axis of the teeth and the central ray of the x-ray beam is directed at right angles to the teeth and receptor”. minimizes geometric distortion and presents the teeth and supporting bone in their true anatomic relationships

6. Instruments Receptor Placement Angulation

7. Modifications If the lack of parallelism does not exceed 20, the radiograph is generally acceptable.̊ Place 1 or 2 cotton rolls on bite block. Increase the vertical angulation by 5 to 15 degrees Shallow palate

8. Modifications For maxilla, place the film on far side of the film. For mandible, place film between the tori and tongue Bony growths

9. ADVANTAGES DISADVANTAGES Accuracy Difficult for a beginner Simplicity Discomfort Duplication Patient Compliance

10. BISECTING ANGLE TECHNIQUE

11. The bisecting-angle technique is based on a simple geometric theorem , Cieszynski ’ s rule of isometry , which states that two triangles are equal when they share one complete side and have two equal angles.

12. Receptor is positioned as close as possible to the lingual surface of the teeth , resting in the palate or in the floor of the mouth. The plane of the receptor and the long axis of the teeth form an angle, with its apex at the point where the receptor is in contact with the teeth. An imaginary line that bisects this angle, direct the central ray of the beam at right angles to this bisector.

13. No film holder required. Better technique when anatomical variations hinder paralleling tech. Decreased exposure time. Advantages

14. To reproduce the length of each root of a multi-rooted tooth accurately , the central beam must be angled differently for each root . (Inaccurate) Another limitation of this technique is that the alveolar ridge often projects more coronally than its true position, thus distorting the apparent height of the alveolar bone around the teeth. Disadvantages

15. to obtain three-dimensional information of location of an object. Object Localization The right-angle (or cross-section) technique The tube shift technique buccal object rule and Clark ’ s rule

16. to obtain three-dimensional information of location of an object. Object Localization The right-angle (or cross-section) technique The tube shift technique buccal object rule and Clark ’ s rule

17. SLOB

18. Bitewing (also called interproximal ) radiographs include the crowns of the maxillary and mandibular teeth and the alveolar crest on the same receptor. Bitewing ( interproximal )

19. interproximal caries in the early stages. secondary caries below restorations . Overhanging restorations. evaluating the periodontal condition.( alveolar bone crest ) detecting calculus deposits. Indications

20. Parallel with the occlusal plane. The aiming cylinder is positioned about + 10 degrees to project the beam parallel with the occlusal plane. Vertical Bitewing Horizontal Bitewing

21. An occlusal radiograph displays a relatively large segment of a dental arch. when patients are unable to open the mouth . localization of objects. To localize foreign bodies in the jaws and stones in the ducts. To demonstrate and evaluate the integrity of the outlines of the maxillary sinus Occlusal View

22. To obtain information about the location, nature, extent, and displacement of fractures of the mandible and maxilla. To determine the medial and lateral extent of disease (e.g., cysts, osteomyelitis, tu mors ) and to detect disease in the palate or floor of the mouth.

23. ANTERIOR MAXILLARY OCCLUSAL PROJECTION Image Field Receptor Placement Projection of Central Ray Point of Entry

24. Image Field Receptor Placement Projection of Central Ray Point of Entry CROSS-SECTIONAL MAXILLARY OCCLUSAL PROJECTION

25. LATERAL MAXILLARY OCCLUSAL PROJECTION Image Field Receptor Placement Projection of Central Ray Point of Entry

26. Image Field Receptor Placement Projection of Central Ray Point of Entry ANTERIOR MANDIBULAR OCCLUSAL PROJECTION

27. Image Field Receptor Placement Projection of Central Ray Point of Entry CROSS-SECTIONAL MANDIBULAR OCCLUSAL PROJECTION

28. Image Field Receptor Placement Projection of Central Ray Point of Entry LATERAL MANDIBULAR OCCLUSAL PROJECTION

29. Special Considerations INFECTION trismus Pain and Difficulty Extra oral Occlusal

30. lack of coordination or inability to comprehend is expected. Speedily Sedation PATIENTS WITH MENTAL DISABILITIES

31. Relax and reassure the patient Describe and explain the procedures Perform the procedure in the morning, Sliding the film along the palate or tongue is likely to stimulate the gag reflex. The longer the receptor stays in the mouth, the greater the possibility that the patient will start to gag. The patient should be advised to breathe rapidly through the nose because mouth breathing usually aggravates this condition. Shift the patient ’ s attention GAG REFLEX