Surgical Removal of Impacted Teeth Flashcards
Definition of Impacted teeth
an impacted tooth is one that fails to erupt into the dental arch within the expected time.
the eruption has been impeded by adjacent teeth, dense bone, or excessive soft tissue
most common impacted? why?
3rd molars – becauwe lase to erupt
then canine – maxillary - because later in eruption as well
general rule about impacted teeth
should be removed unless removal is contra-indicated
ideal time for 3rd molar removal
when the roots of the teeth are on-third formed and before they are 2/3 formed
usually between the ages of 17 and 20
indications for removal of impacted teeth (long list)
- prevention of perio disease
- prevent caries
- prevent pericornitis
- prevention of root resorption
- impacted teeth under a dental prosthesis
- prevention of odontogenic cysts and tumors
- tx of pain of unexplained origin
- prevention of jaw fracture
- facilitation of orthodontic treatment
- optimal periodontal healing
main reason to remove the 3rd molars
Periodontal disease prevention
study regarding the dominant hand *
no difference
pericorinitis
definition and describe
seen in partially erupted teeth with large amounts of soft tissue over the occlusal surface
it is an infection of the soft tissue around the crown
caused by noraml oral flora
host defense maintain balance
pericorinitis secondary to
to minor trauma from the maxillary third molar - traumatizes the operculum over the partially erupted mandibular 3rd molar
take out opposing third molar to diminish pericorinitis
yes – could be harmful to the tooth having pericorinitis
pericorinitis caused by
streptococci and anaerobic bacteria
can be mild to severe
tx for periorintis
mild?
moderate?
severe?
mild – irrigation
moderate – tx with antibiotics
severe – facial space infections - trismus, temp greater than 101 F, mailaise, facial swelling, pain – need referral and possible hospital admit.
tx for periorintis
mild?
moderate?
severe?
mild – irrigation
moderate – tx with antibiotics
severe – facial space infections - trismus, temp greater than 101 F, mailaise, facial swelling, pain – need referral and possible hospital admit.
operculectomy?
usually does not work to cure the pericoriniits – tends to recur
risk factors for external root resoprtion of second molars associated with impacted third molars?
increased with age and with mesioangular and horizontal inclincations
impacted tooth removal before other tx?
yes - should be removed before prosthesis is constructed - because if the impacted tooth must be removed after construction, the alveolar ridge may be so altered by the extraction that the prosthesis becomes unaatractive and less functional
operculum is?
soft tissue covering an impacted / partially erupted tooth
odontogenic cysts and tumors association
it is recommended that impacted teeth be removed to prevent the occurence of cysts and tumors
diagnosis of a dentigerous cyst is reasonable when?
if the follicular space around the crown of the tooth is greater than 3mm, the diagnosis of a dentigerous cyst is reasonable
most common odontgenic tumor
ameloblastoma in the third molar region
relative contraindications for removal of impacted teeth
- over age 40
2.
over age 40 details
- highly calcified brittle bone
- prolonged healing time
- anesthesia considerations
impacted teeth classification
- angulation
impacted teeth classification
- angulation
impacted teeth classification in terms of angulation
- angulation
- mesio-angular
- horizontal
- vertical
- distoangular
mesioangular impaction details
*generally acknowledged as the least difficult to remove in the mandible
tilted toward the second molar in a mesial direction
approx. 43% of all impacted mandibular third molars
horizontal impaction
approx 3% (based on info we have) of mandibular impactions
second ‘ easiest
classification (3 caegories)
- angulation
- relationship to the anterior border of the ramus
- relationship to the occlusal plane
relative contraindications to removal of impacted teeth
- probable damaeg to adjacent structures
- nerves
- major blood vessels
- teeth
- prostheses - long standing asymptomatic tooth
age when relative contraindications to removal of impacted teeth
over 40
- highly calcified brittle bone
- prolonged healing time
- anesthesia considerations
Medical status
- ASA classification
vertical impaction
long axis of the tooth runs in the same direction as the long axis of the second molar
approx. 38%
the third most difficult to remove
*distoangular impaction details
the MOST difficult angulation for removal of mandibular impacted tooth
long axis of the third molar is distally or posteriorly angled AWAY from the second molar
its path of withdrawl runs into the mandibular ramus *
approx. 6% of mandibular third molars
PG / Pell and Gregoy classsification
- Relationship to the anterior border of the ramus
1,2,3
- Relationship to the occlusal plane
A,B, and C
PG classification 1
the mesiodistal diameter of the crown is completley anterior to the anterior border of the ramus
PG classification 2
approx. half the crown is covered by the anterior border of the ramus
PG classification 3
the crown is covered entirely by the anterior border of the ramus
normal development of the lower third molars sequence
starts at disto-angular – changes to mesio-angular – then to vertical
usual time of eruption of the 3rd molars
20 – can continue to erupt into the age of 25
