Surgical Management Of Impacted Teeth

Question 1

Soft tissue impaction vs bony impactions

Answer 1

Soft tissue:
- tooth almost erupted
- crown above alveolar bone level
- covered partially by dense fibrous operculum

Bony impaction:
- obstruction by overlying alveolar bone
- partial: part of the tooth will be visible after flap raised
- complete: will require bone removal before tooth is visible

Question 2

What is winters classification?

Answer 2

• inclination of impacted tooth to the long axis of the second molar
• mesioangular, horizontal, vertical, disto angular, transverse

Question 3

What is Pell and Gregory’s classification?

Answer 3

• Based on relationship of lower wisdom tooth to the occlusal plane and the anterior border of ramus

Occlusal plane:
Class A - same level as second molar
Class B - between occlusal plane and cervical margin of second molar
Class C - below the cervical margin

Anterior border of ramus:
Class 1: entire mesiodistal width of crown of 3rd molar is anterior
Class 2: half of crown of third molar is anterior
Class 3: 3rd molar totally embedded in bone of anterior border ramus

Question 4

When are divergent roots easy/hard for extraction

Answer 4

Easy: when horizontally impacted and splitting tooth in half

Hard: vertical impaction

Question 5

What are some contraindications for extractions

Answer 5

1) fully impacted, asymptomatic
2) no communication with oral cavity
3) compromised medical status
4) proximity to vital structures

Question 6

How to see if tooth is near root?

Answer 6

Take CBCT

Question 7

List the surgical steps to remove an impacted tooth

Answer 7

1) anesthesia
2) incise
3) raise mucoperiosteal flap
4) gutter bone
5) section tooth if necessary
6) elevate tooth
7) irrigate tooth
8) suturing
9) post op instructions

Question 8

Principles to a good incision and flap

Answer 8

• adequate access to underlying tooth and bone
• resist tearing (sharp blade, firm continuous strokes)
• mucoperiosteal flap
• broad base with blood supply

Question 9

Describe the envelope flap

Answer 9

• ascending ramus
• distobuccal surface of the second molar
• extended as a sulcular incision
• cut buccal to avoid lingual nerve
• start from 7 if 8 cannot be seen, cut from 8 if can be seen slightly

Question 10

Describe triangular flap

Answer 10

Along ramus and downwards buccally (parallel to long axis of tooth)

Question 11

Describe lingual based flap

Answer 11

V shape looking at buccal mucosa

Question 12

Describe coronectomy

Answer 12

• deliberate root retention
• angle of but at approx 45 degrees and lingual retractor protecting lingual nerve
• triangle area of root on buccal side to be removed secondarily

Question 13

What are the indications for wisdom teeth removal?

Answer 13

1) Presence of disease
- caries
- periodontitis/ pericoronitis
- infection: cellulitis/abscess/osteomyelitis
-> Ludwig angina (severe cellulitis) -> swelling of submandibular, submental space, constrict of airways, can die from respiratory destress
- internal/external resorption of tooth/adjacent tooth
- cyst or tumour