Impacted Teeth

Question 1

Most commonly impacted Teeth

Answer 1

• Third molars
• Maxillary Canines
• Mandibular premolars

Question 2

Teeth become impacted due to

Answer 2

Lack of space

Question 3

Classification of Third molar impaction

Answer 3

• Winters classification
• Pell and Gregory classes/levels
• Pederson’s difficulty index
• Modified Parant scale
• Wharfe assessment by McGregor

Question 4

Winters classification

Answer 4

Angulation of the teeth

• Mesioangular
• Horizontal
• Vertical
• Distoangular
• Inverted

Question 5

Pell and Gregory Classes

Answer 5

• Based on relationship between third molar and ramus
• Class 1→ Crown anterior to ramus
• Class 2→ Crown is partially in ramus
• Class 3→ Tooth in ramus

Question 6

Pell and gregory levels

Answer 6

• Measures degree of overlying bone
• Level A→ Occlusal planes level
• Level B→ Occusal plane half way between second molar
• Level C→ Occlusal plane below cervical line

Question 7

Pederson’s difficulty index

Answer 7

• Measure difficulty by angulation, occlusal height and space→ Value assigned
• Low accuracy→ doesn’t take into account other factors(mouth opening, bone density ect)

Question 8

Modified Parant scale

Answer 8

Difficulty index

• Easy 1→ forceps
• Easy 2→ osteotomy

Difficult 3→ osteotomy and coronal section(crown and root removed separately)

Difficult 4→ Root sectioning

Question 9

Winter war lines

Answer 9

-White lines → Occlusal plane

Yellow line→ Height of bone level

Red line→ Point of elevator application

Question 10

Wharfe assessment by McGregor

Answer 10

Difficulty index

• Angulation
• Height of bone
• Root shape
• Follicle development
• Path of exit