1. The Bitewing Technique
Reference reading: Chapter 19

2. Objectives for Bitewings:
Show interproximal caries
Show pulp changes
Show overhangs
Display improperly fitting crowns
Shows recurrent caries beneath restorations
Show resorption of alveolar bone

3. Alveolar Bone

4. Contact Areas

5. Diagnostic Image

6. Caries on #30 D

7. Crestal Bone Height

8. Alveolar Bone Loss

9. Crown Margins

10. Overhanging Amalgam and Crown

11. Recurrent Caries #29 M

12. Pulp Stone

13. The Bitewing Technique
Is a method used to examine the inter- proximal surfaces of the teeth (where the explorer doesn’t reach).
Considered a method of preventive dentistry.
Is a radiographic exam that is used the most frequently in conjunction with dental exams and cleanings.

14. How it works:
X-ray beams pass through teeth at a 90 degree angle, which creates a more accurate image of structures.
The use of paralleling technique creates the illusion of open contacts, giving the appearance that there are spaces between the teeth.
Appears radiolucent (BLACK)
Show the crowns of both upper and lower teeth, as well as the supporting alveolar bone, on a single film.

15. Vertical Angulation

16. Principles of Bite-wing Technique:
The film is placed in the mouth parallel to the crowns of both the upper and the lower teeth
The film is stabilized when the patient bites on the bite-wing tab or film holding device.
The central ray of the x-ray beam is directed through the contacts of the teeth, using vertical angulation of +10 degrees

17. The Bite-wing Tab
The Bite-wing tab: this is a sticky tab that is placed on the tube side of the film packet.
The patient bites directly on the tab, and therefore establishes a better image because the teeth are fully closed, and there is no bite-block interference.

18. Bite-wing Tab

19. Film Holding Devices - Rinn
Rinn XCP Bitewing instrument:
Just like the Rinn for periapical films, the Rinn bite-wing holder will position the film, stabilize it, and align the PID for a good diagnostic film.

20. Bite-Wing Radiograph Views
Premolar view:
angle the PID at +10 degrees vertically;
horizontally aim toward center of film, between the premolars and the occlusal plane
Center tab on 2nd premolar
Molar view:
angle the PID at +10 degrees vertically,
horizontally aim at contacts of 1st and 2nd molars
Center tab on 2nd molar

21. Posterior Teeth

22. Premolar Curvature

23. Premolar Placement and Image

24. Molar Area

25. Molar Placement and Image

26. Four sizes of film are used for BWX
Size 0 = pediatric patient with primary dentition
Size 1 = children with mixed dentition
Size 2 = teens and adult patients
Size 3 = horizontal bitewings only;
not recommended due to overlapped contact results

27. Vertical Bite-wings
Can be used to examine the level of supporting bone in the mouth.
The bite-wing is placed in a vertical, up and down, direction.
Mainly used for periodontal patients.

28. Modified CMRS using Vertical Bite-wings
A total of 7 projections are used to cover all areas.

29. Image of Anterior Vertical Bitewing

30. The importance of angulation:
The whole purpose of the bitewing examination is to see the interproximal areas of the teeth.
If horizontal angulation is incorrect, the contacts will be overlapped, and produce a film of poor diagnostic quality. To avoid overlap, direct the CR through the interproximal areas of the teeth.
If the vertical angulation is incorrect, the image will be distorted, and also of poor diagnostic quality

31. Open Contacts: Desirable Image

32. Overlapping: non-diagnostic

33. Negative Angulation: non-diagnostic

34. Modifications to the BW Technique
Edentulous Areas
A cotton roll must be placed in the area of the missing teeth to support the bite-wing tab.
Failure to support the BW tab results in a tipped occlusal plane on the radiograph.
Bony Growths (tori)
Mandibular tori may cause a problem in film placement.
The film must be placed between the tori and the tongue, not on the tori.

35. Helpful Hints BEFORE PLACING FILM IN PATIENT’S MOUTH:
Set exposure factors
(kVp, mA, exposure time)
Ask patient to remove all intraoral objects and eyeglasses
Check the oral anatomy
Tori? Shallow or narrow palate?
Limited opening?
Attempt to retract cheeks and tongue to gauge difficulty during film placement.