Surgical Removal of Impacted Teeth I & II

Lecture given 8/18/2026

impacted teeth

a tooth that fails to erupt into the dental arch within the expected time

the eruption has been impeded by adjacent teeth, dense bone, excessive soft tissue, or genetics

which teeth are most commonly impacted?

max and mand 3rd molars

max canines

mand premolars

when does the maxillary canine usually erupt?

after the max lateral incisor and after the max first premolar

when does the mand premolar usually erupt?

after the mand 1st molar

after the mand canine

what is the guidance around impacted teeth removal?

all impacted teeth should be removed unless their removal is contraindicated

if indicated for extraction, they should be extracted as soon as it is determined the tooth is impacted

it should not be recommended that the teeth be left in place until they cause problems

what did the AAOMS task force for 3rd molars find/suggest?

all impacted teeth should be considered for removal

the average age for completion of the eruption of the 3rd molar is 20 yo although eruption may continue in some pts to age 25

the normal development for the lower 3rd molars begins in a horizontal angulation that changes to mesioangular and then to vertical

when is the ideal time for 3rd molar removal?

when the roots are 1/3 formed but before they are 2/3 formed

usually between the ages of 17 and 20

what are the indications for removal of impacted teeth?

prevention of periodontal disease

prevention of dental caries

prevention of pericoronitis

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

what did the VA longitudinal study over 25yrs and 416 adult men find?

the lowest prevalence and incidence of 2nd molar pathology (caries and/or periodontitis) occurred when the adjacent 3rd molar was absent

a 3rd molar that was soft tissue impacted increased the risk of pathology 4.88 fold

an erupted or bony 3rd molar impaction increased the risk 1.74 fold and 2.16 respectively

TLDR: the retention of 3rd molars is associated with increased risk of second molar pathology in middle aged and older adult men

pericoronitis

seen in partially erupted teeth with large amount of soft tissue over the occlusal surface

it is an infection of the soft tissue around the crown

it is caused by normal oral flora- streptococci and anaerobic bacteria

host defense maintain balance

it can arise secondary to minor trauma from the max 3rd molar- traumatizes the operculum over the partially erupted mand 3rd molar

can be mild to severe

treatment for mild pericoronitis

irrigation

treatment for moderate pericoronitis

antibiotics

symptoms and treatment for severe pericoronitis

facial space infections- trismus, temp greater than 101F, malaise, facial swelling, pain

need referral and possible hospital admit

operculectomy

usually does not work, it tends to recur

Which of the following is true regarding impacted third molars?

A) If they are to be extracted, they should be extracted when the roots are three quarters
developed but before they are fully developed

B) If pericoronitis develops with an erupting tooth, it is usually caused by normal oral flora

C) The average age for completion of the eruption of the third molar is 10 years of age

D) The normal development for the lower 3rd molar begins in a Vertical Position

B) If pericoronitis develops with an erupting tooth, it is usually caused by normal oral flora

_____ and _____ inclinations and impacted mand 3rd molars posed a greater risk of ERR (external root resorption) lesions in adjacent second molars than other inclinations (_______ and ______) and max 3rd molars

mesioangular, horizontal

distoangular, vertical

why should impacted teeth be removed before a prosthesis is constructed?

if the impacted tooth must be removed after construction, the alveolar ridge may be altered by the extraction that the prosthesis becomes unattractive and less functional

if the follicular space around the crown of the unerupted tooth is greater than 3mm the diagnosis of _____ is reasonable

dentigerous cyst

the most common odontogenic tumor in the 3rd molar region is ______

ameloblastoma

how can removing the 3rd molars help to prevent jaw fracture?

impacted mand 3rd molar occupies space that is usually filled with bone- this may weaken the jaw and make it more susceptible to fracture

if a fracture of the mandible occurs through the area of the impacted tooth, the tooth is frequently removed

how can removing impacted 3rd molars facilitate orthodontic treatment?

prevent crowding of mand anterior teeth after ortho treatment has been complete

what are relative contraindications for extracting impacted teeth?

age > 40

medical status

probable damage to adjacent structures like nerves, major blood vessels, teeth, prostheses

a long standing asymptomatic impacted tooth

why are extractions of impacted teeth on people age 40 and up relatively contraindicated?

highly calcified, brittle bone

prolonged healing time

anesthesia considerations

what are the angulation classifications (winter’s classifications) for impacted teeth?

mesioangular

horizonal

vertical

distoangular

what angle is this?

mesioangular

mesioangular impaction

generally acknowledged as the least difficult to remove in the mandible

it is tilted toward the second molar in a mesial direction

what angle is this?

horizontal

horizontal impaction

second most easy mand impaction to remove

what angle is this?

vertical

vertical impaction

long axis of the impacted tooth runs in the same direction as the long axis of the second molar

the 3rd most difficult mand impaction to remove

what angle is this?

distoangular

distoangular impaction

the most difficult angulation for removal of mandibular impacted tooth

the long axis of the 3rd molar is distally or posteriorly angled away from the second molar

its path of withdrawal runs into the mandibular ramus

PG class 1

the mesiodistal diameter of the crown is completely anterior to the anterior border of the ramus

PG class 2

approx ½ of the crown is covered by the border of the ramus

PG class 3

the crown is covered entirely by the anterior border of the ramus

PG class A

the occlusal plane of the impacted tooth is at the same level as the occlusal plane of the second molar

PG class B

the occlusal plane of the impacted tooth is between the occlusal plane and the cervical line of the second molar

PG class C

the occlusal plane of the impacted tooth is below the cervical line of the second molar

what is the PG classification?

mesioangular, 1, A

what is the PG classification?

horizontal, 2, B

what is the PG classification?

distoangular, 3, C

what is the classification for nature of overlying tissue?

soft tissue- full or partial

bone- full or partial

what is the classification of overlying tissue?

full soft tissue

what is the classification of overlying tissue?

partial bone

what is the classification of overlying tissue?

full bone

How would you classify this impacted mandibular third molar?

A) Horizontal, Class 2, B

B) Mesial angular, Class 1, C

C) Vertical, Class 3, B

D) Vertical, Class 1, C

C) Vertical, Class 3, B

what angle is this?

vertical

what angle is this?

distoangular

what angle is this?

mesioangular

what classification is this?

PG A

what classification is this?

PG B

what classification is this?

PG C

how does root length impact extraction of impacted teeth?

longer, thin root makes extraction harder

how does single or fused root impact extraction of impacted teeth?

single/fused makes it easier to extract compared to multiple, splayed roots

how does root curvature impact extraction of impacted teeth?

less curvature is easier to extract

how does age and bone density affect extraction of impacted teeth?

younger pts have less dense bone, which makes for easier extractions

how does the size of follicular sac impact extraction of impacted teeth?

the bigger follicle makes extraction easier

factors that make impaction surgery LESS difficult

mesioangular postion in the mandible

class I ramus

class A depth

roots 1/3 to 2/3 formed

fused conical roots

wide PDL

large follicle

elastic bone

separated from the second molar

separated from IAN

soft tissue impaction

factors that make impaction surgery MORE difficult

distoangular in mandible

class III ramus

class C depth

long, thin roots

divergent curved roots

narrow PDL

thin follicle

dense, inelastic bone

contact with the second molar

close to the IAN

complete bony impaction

Which of the following make the extraction of an impacted tooth more difficult?

A) A tooth with a large follicle

B) Roots one third to two thirds formed

C) Fused conical roots

D) Narrow periodontal ligament

D) Narrow periodontal ligament

t/f increased age (>25 yrs) appears to be associated with a higher complication rate for M3 extractions

true

what is a basic outline of the surgical procedure for impacted teeth?

adequate exposure

bone removal

section tooth

deliver tooth from alveolar process

wound debrided, irrigated, and closed

are maxillary teeth commonly sectioned?

no, mostly just bone removal because of concerns with the maxillary sinus

DO NOT use chisel to section a maxillary tooth

as compared to removal of impacted 3rd molars, there is _____ luxation of other impacted teeth for the purpose of expansion of the buccal or linguocortical plate

almost NO

bone is removed and tooth is section

what is the perioperative pt management needed?

anxiety control- IV sedation or GA

long acting local anesthetics

IV steroids to prevent/decrease swelling

post-op instructions

potent oral analgesics

ice packs on the face

possible use of antibiotics

does cold therapy work to reduce pain, trismus, and swelling after dentoalveolar surgery?

no

should a pt be prescribed perioperative oral antibiotics?

no- no measured benefit or reduction in postoperative complications

what is a normal postoperative experience for a pt?

swelling, up to ~3 days

discomfort

mild to moderate trismus

all of the sequelae of the removal of impacted teeth are of less intensity in the young, healthy pt

pt evaluation prior to surgery

CC, HPI, PMH, PSH, SH, meds, allergies

physical exam, radiographic evaluation

are CT before 3rd molar extraction necessary?

no, most of the time it did not effect surgical outcome, HOWEVER CBCT can improve localization of 3rd molar for presurgical planning

what are some complications of impacted mandibular 3rd molars?

injury to IAN or lingual nerve

hemorrhage

jaw fracture

retained roots

root displaced into the submandibular space

dry socket

alveolar osteitis

a clinical diagnosis that is characterized by the development of moderate to severe throbbing pain usually occuring around the 3rd to 5th day after surgery and is often confused with an earache, headache, or pain from another tooth with no evidence of pathologic condition

halitosis is usually present

extraction socket is partially or completely devoid of a clot or is often filled with debris and shows evidence of poor healing

the exposed bone is the source of pain, which may radiate

the area of the socket has a bad odor

no usual signs or symptoms of infection (fever, swelling, and erythema) are present

0.3-26% prevelance

occurs more frequently in the mandible

what causes alveolar osteitis?

poorly understood

result of release of tissue factors leading to the activation of plasminogen and the subsequent fibrinolysis of the blood clot

result of a localized bacterial infection

what factors may contribute to alveolar osteitis?

increasing age, female, oral contraceptives, smoking, surgical trauma, pericoronitis, experience of the surgeon, poor oral hygiene

sighting an exposed intact IAN bundle during 3rd molar surgery indicates its intimate relationship with the 3rd molar and carries a ____ risk of paresthesia, with a ___ chance of recovery by 1 year from surgery

20%

70%

what are complications of impacted maxillary 3rd molars?

hemorrhage

fractured tuberosity

sinus exposure

retained root tips

displacement of root tip or tooth into maxillary sinus

displacement of tooth into infratemporal fossa

Which of the following is not considered to be complication associated with the extraction of a mandibular impacted third molar?

A) Injury to IAN or Lingual Nerve

B) Jaw fracture

C) Root/tooth displaced into the infratemporal fossae

D) Dry socket

C) Root/tooth displaced into the infratemporal fossae

t/f a majority of complications requiring hospitalization resulted from healthy 3rd molars and their removal

false- diseased

mesioangular, class 2, C

horizontal, class 2, B or C

what are some radiographic predictors of potentional tooth proximity to the IAN?

darkening of the tooth

deflection of the rot

narrowing of the root

dark and bifid root apex

interruption of the white line of the canal

diversion of the canal

narrowing of the canal

what are the arrows pointing at?

shadowing on the roots of the mandibular 3rd molars, indicated proximity to IAN

coronectomy

removing the crown of the tooth, leaving the roots in place

must remove the crown at the CEJ, no more enamel can remain!

what are some myths associated with wisdom tooth extraction?

3rd molars have the higest incidence of pathology

early removal of 3rd molars is less traumatic (not extracting the tooth is the least traumatic)

pressure of erupting 3rd molars causes crowding of anterior teeth

the risk of pathology in impacted 3rd molars increases with age

there is little risk of harm in the removal of 3rd molars

should we follow NICE guidelines?

not really- people still end up extracting 3rd molars, just happens at an older age which isn’t great

what are common reasons for retaining 3rd molars?

risk of damaging adjacent structures

compromised health status

adequate space for eruption

third molar serves as an abutment tooth

orthodontic reasons

eruption into proper occlusion

symptomless 3rds in pts over 30 yrs

pt preference

bold are most common