1.  
   1. place film on lingual surface
   2. the film and the long axis form an angle
   3. the imaginary bisector creates two equal angles and provides a common side for the two imaginary equal triangles
   4. x-ray beam perpendicular to the imaginary bisector, the central ray is directed at 90
   5. the two imaginary  triangles that result are right triangles and congruent

•  
  • not recommended but the finger can be used to stabilize the film with the bisecting technique
  • Thumb stabilizes the maxillary digital sensor
  • Index finger stabilizes the mand. sensor

What are the disadvantages of the finger-holder method (digital method)

(4)

1.  
   1. unnecessary radiation exposure to patient
   2. excessive force on the film can bend and distort the image
   3. film could slip
   4. alignment could be off

Size 2 film vertical in the anterior and horizontal posterior

The central ay is directed perpendicular to the curvature of the arch and through the contact area of the teeth allowing the contact areas on to appear open

What happens with incorrect horizontal angulation of the bisecting technique?

What are the mandibular vertical angulation in degrees for.....

1.  
   1. canines
   2. incisors
   3. premolars
   4. molars

1.  
   1. canines +45 to +55
   2. incisors +40 to +50
   3. premolars +30 to +40
   4. molars +20 to +30

1. canine -20 to -30
2. incisor -15 to -25
3. premolar -10 to -15
4. molar -5 to 0

1. Film placement
2. film position
3. vertical angulation
4. horizontal angulation
5. film exposure

Advantage

1. Don't have to use a film older
2. decreased exposure time

Disadvantages

1. image distortion
2. angulation problems
3. unnecessary (repeated)exposure