Class I Malocclusion

Question 1

Orthodontic Treatment Goals

Answer 1

• Correct factors that precipitate risk of dental diseases/conditions
• Enhance quality of life

Question 2

Definition of Malocclusion

Answer 2

(Guilford 1889)
Any deviation from ideal occlusion

Question 3

Malocclusion is most prevalent in which Class

Answer 3

Class I

Question 4

Dental Components of Class I Malocclusion
9

Answer 4

• Spacing
• Crowding
• Displacement
• Supernumerary
• Hypodontia
• Buried teeth
• Tooth shape anomaly
• Variation in teeth inclination/angulation
• Crossbite

Question 5

Skeletal Components of Class I Malocclusion

Answer 5

1. Dentoalveolar Compensation (DAC) and Steiner’s Compromises

Even though ANB>2 (Class II Skeletal Base), if the upper incisor is retroclined, it can still be Class I Incisal R/S

Even though ANB<2 (Class III Skeletal Base), if the upper incisor is proclined, it can still be Class I Incisal R/S

2. Vertical excess and deficiency
3. Skeletal Asymmetry

Question 6

Criteria for Class I

Answer 6

BSI Classification
OJ of 2-3mm
OB of > 1mm to limit of lower incisal show

Question 7

Tx for Bimax Protrusion

Answer 7

Orthognathic surgery

Question 8

Tx Principle

Answer 8

Most ideal: Correct the source of the problem - correct diagnosis is key
Alternative: Camouflage (using extractions therapy if necessary)