positioning of facial bones

Question 1

Facial bones routine:

Answer 1

• lateral
• caldwell
• waters
• townes
• SMV (submentovertical) for zygomatic arches

Question 2

Reverse caldwell for facial bones

Answer 2

• 15 degree cephalad, 110 SID
• have markers and shielding ready to go
• pt laying AP on table
• go to head of table to make sure there is no rotation or tilt
• can move mattress or pts face
• (-) starting at the naisson
• head position: OML (get pt to tuck chin)
• bottom of light at maxilla
• top of light: vertex
• side to side: finger width of light on either side
• marker by top of head
• hold breath

***Caldwell for facial bones would be the exact same except the pt would be PA at the wall detector with pt sitting on stool back towards us, and 15 degree caudad

Question 3

Townes for facial bones

Answer 3

(always done AP)

• 30 degree caudad, 110 SID
• OML (get pt to tuck in chin)
• go to head of table and look over pt to check for tilt and rotation
• line up tube and detector
• pt lying on their back on the table
• have enough light for the marker to go in the bottom corner
• (-) start at the globella
• top of light: above EAM (just a smidge) EAM/TEA area
• bottom of light: below mandibular angle (V ridge near gonion or jaw)
• hold breath

Question 4

Reverse waters for facial bones

Answer 4

• no angle, 110 SID
  pt laying on thier back on the table
• want pt closer to foot end and detector at head end
• for head positioning: corner of lip attachment to TEA
• (-) over acanthion (just below the nose), exiting EAM and corner of mouth just 2 fingers above
• bottom of light: maxilla (to bottom of top incisors)
• top of light: superior orbital margin (above eye sockets)
• marker in top lateral
• super tight coning, just a little light on either side
• check for rotation and tilt at the head end of the table
• hold breath

*** can do on the upright wall detector (waters) would be PA instead of AP and that would be the only difference

Question 5

lateral for facial bones (x-table)

Answer 5

• 100 SID, landscape, medium cassette
• tape cassette up (want bottom of it hitting against pts shoulders) get pt to relax and lower shoulders abit so more room for cassette to go up against them
• use measuring tape from tube to cassette to get the SID
• IOML
• side to side: want half of the EAM included
• top of light: roughly at the hair line
• bottom of light: 1 finger below chin
• only need half of frontal bone to include the chin
• (-) around EAM (aka zygoma)
• check for rotation and tilt at head end of the table
• maker in bottom corner at a slant by the chin
• dont want to clip bony anatomy of nose but can clip the tip of the nose

**** if doing lateral on the upright wall detector the only difference would be that the SID is 110 cm

Question 6

Zygomatic arches (bilateral) for facial bones aka SMV

Answer 6

• use a small cassette, landscape, 100 SID
• 60 degree angle cephalad on tube
• use measuring tape to cassette to get SID
• pt laying on their back on the table
• build up sponges to 60 degrees (put the small sponge under the 45 degree sponge)
• small cassette right behind the pts head, sandbags used to hold up sponges and cassettes
• marker goes on top corner of cassette at a slant
• (-) at gonion, the squish under chin where you could kill people
• IOML parallel to angle of cassette (tilt pts chin up)
• top of light: two fingers above arches (cheekbones)
• bottom of light: gonion
• finger width of light on either side (side to side)
• (I) on MSP
• hold breath

Question 7

zygomatic arches (unilateral) for facial bones aka SMV

Answer 7

• use a small cassette, landscape, 100 SID
• 60 degree angle cephalad on tube
• use measuring tape to cassette to get SID
• pt laying on their back on the table
• build up sponges to 60 degrees (put the small sponge under the 45 degree sponge)
• small cassette right behind the pts head, sandbags used to hold up sponges and cassettes
• marker goes on top corner of cassette at a slant
• no pillow under pts head
• IOML parallel to angle of cassette (tilt pts chin up)
• top of light: two fingers above arches (cheekbones)
• bottom of light: gonion
• finger width of light on either side (side to side)
• rotate pts face to the affected side, and rotate their chin 15 degrees to the affected side
• hold breath
• head on mattress but sponges, cassette, etc dont need to be on it