A patient with an open lip posture and a jaw relationship in which the upper teeth protrude relative to the lowers has which occlusion?

• A. Class 2 division 1 malocclusion
• B. Class 1 normal occlusion
• C. Class 3 malocclusion
• D. Open bite

Answer: (A)

When the upper teeth sit in front of the lower teeth and the front teeth are inclined forward, you’re looking at a Class II Division 1 malocclusion. This pattern means the upper molars are positioned ahead of the lower molars (a Class II relationship), and the incisors themselves are proclined, producing an increased overjet where the upper teeth project ahead of the lowers. An open lip posture at rest often accompanies this because the lips don’t fully close over the prominent upper incisors. The other options don’t fit: normal occlusion would not have protruding upper teeth; a Class III malocclusion would show the lower teeth ahead of the upper (reverse overjet); and an open bite describes a vertical gap between the anterior teeth, not simply forward-projected incisors.