third molars 2

Question 1

why is it important to rule out any TMJ problems prior to third molar surgery

Answer 1

TMD pain can mimic pericoronitis and vice versa
Essential to rule out TMD as source of pain

Question 2

working space
(with regards to third molars)

Answer 2

distance from distal of M2M to ascending ramus

Question 3

when doing a radiographic report for third molars, what aspects of the 3M anatomy should be included

Answer 3

crown size
shape
condition
root formation and shape, particularly any hooks or curves
crown to root ratio (small crown and large root = surgical)

Question 4

what are the 5 (6)different types of impaction

Answer 4

vertical
mesial
distal
transverse
horizontal
(aberrant)

Question 5

what should be included in a radiographic report for 3rd molars

Answer 5

DAWIPI
presence or absence of Disease
Anatomy of 3M
Working distance
Impaction - depth + orientation
Pathology - anything
proximity to Important structures

Question 6

what 3 signs on a radiograph are associated with significantly increased risk of nerve injury during third molar surgery
(according to SIGN and FDS guidelines)

Answer 6

diversion of IA canal
darkening of root where crossed by canal
interruption of white lines of canal

Question 7

what are the 8 radiographical signs of close proximity to IAN canal

Answer 7

1. interruption of white lines/ lamina dura of canal
2. darkening of root where crossed by canal
3. diversion/ deflection of the canal
4. deflection of root (not all curved roots are due to to deflection from the canal)
5. narrowing of canal
6. narrowing of root
7. dark and bifid root (root appears to split and divide over the canal)
8. juxta apical area

Question 8

juxta apical area around a 3M

Answer 8

(well circumscribed radiolucent region adjacent to apex of 3M, usually well defined margins that may appear corticated, lamina dura around tooth still intact)
indicative of close proximity to IA canal

Question 9

what is the most common angulation of impaction for 3rd molars

Answer 9

mesial (40%)

Question 10

what does an aberrant 3M mean

Answer 10

third molar is inunexpected location e.g ramus

Question 11

what is transverse impaction of third molars

Answer 11

crown in buccally placed and roots lingual or vice versa

Question 12

what is angulation and orientation of 3rd molars measured against

Answer 12

curve of spee
(natural curve of cusps of natural dentition)

Question 13

what are the 3 categories of depth of impaction

Answer 13

superficial - crown of 8 related to crown of 7
moderate - crown of 8 related to crown and root of 7
severe - crown of 8 related to root of 7

Question 14

when would a coronectomy be considered

Answer 14

if roots are in close proximity to ID canal, attempt to preserve nerve

Question 15

how long do sutures take to dissolve

Answer 15

2-3 weeks

Question 16

how would you describe the possibility of nerve damage during 3M surgery when gaining consent from a patient

Answer 16

if occurs will be a sensory not a motor deficit so no change to appearance of face
If damage does occur it is uaully temporary and can take up to 9 months to heal, in rare circumstances up to 24 months. After this time damage is likely to be permanent.
Damage could result in a numbness, tingling or painful sensation

Question 17

what are the percentages of patients affected by temporary and permanent nerve damage after 3rd molar surgery

Answer 17

temporary 2-20%
permanent <1%

Question 18

what 2 nerves could be damaged during 3rd molar surgery and what will be affected if they are

Answer 18

IAN - lip, chin, teeth
lingual - one side of tongue , taste (chorda tympani)

Question 19

what format should referrals for 3rd molar surgery follow

Answer 19

SBAR
situation
background
assessment
recommendation

Question 20

what typeo of consent is required for surgical removal of 3rd molars

Answer 20

written consent