Third Molars 1

Question 1

when do 3rd molars usually erupt

Answer 1

18-24 years

Question 2

what is the most common reason third molars fail to erupt

Answer 2

impaction

Question 3

what are three possible consequences of impacted 3rd molars

Answer 3

caries
pericoronitis
cyst formation

Question 4

name 4 nerves at risk during 3rd molar surgery

Answer 4

IAN
lingual nerve
nerve to mylohyoid
long buccal nerve

Question 5

what are four therapeutic indications of extractions of 8s

Answer 5

infection
cysts
tumours
external resorption of 7 or 8

Question 6

what are 6 surgical indications for extraction of 8s

Answer 6

high risk of disease
medical indications
accessibility
patient age
auto-transplantation
GA

Question 7

what is pericoronitis

Answer 7

inflammation around the crown of a partially erupted tooth - food and debris get trapped under operculum resulting in inflammation

Question 8

what anaerobic microbes can be found in pericoronitis

Answer 8

streptococci
actinomyces
a beta-lactamase producing prevotella

Question 9

treatment of pericoronitis

Answer 9

incision of localised pericoronal abscess
local anaesthetic
irrigation with warm saline or chlorhexidine
extraction of 8

Question 10

what are five predisposing factors of pericoronitis

Answer 10

partial eruption and vertical or disto-angular impaction
poor oral hygiene
upper respiratory infections
full dentition
opposing 8 causing mechanical trauma causing recurrent infection