Definitions and Classifications Flashcards
What is an Overjet?
Distance between the upper and lower incisors in the horizontal plane.
What is an Overbite?
Overlap of the incisors in the vertical plane.
What is a complete overbite?
The lower incisors contact the upper incisors or palatal mucosa.
What is an incomplete overbite?
The lower incisors do not contact the upper incisors or the palatal mucosa.
What is an anterior open bite?
No vertical overlap of the incisors when the buccal segment teeth are in occlusion.
What is the Class 1 incisor relationship?
Lower incisor edge occludes with or lies below the cingulum of the upper incisors.
What is the Class 2 div 1 incisor relationship?
Lower incisor edge lies posterior to the cingulum of the upper incisors.
Usually proclined upper central incisors.
Increased overjet.
What is the Class 2 div 2 incisor relationship?
Lower incisor edge lies posterior to the cingulum of the upper incisors.
Usually retroclined upper central incisors.
Decreased overjet.
What is the Class 3 incisor relationship?
Lower incisor edge lies anterior to the cingulum of the upper incisors.
Decreased or reversed overjet.
What is the Class 1 molar relationship?
The mesiobuccal cusp of the upper first molar occludes with the mesiobuccal groove of the lower first molar.
What is the Class 2 molar relationship?
The mesiobuccal cusp of the upper first molar occludes anterior/mesial to the mesiobuccal groove of the lower first molar.
What is the Class 3 molar relationship?
The mesiobuccal cusp of the upper first molar occludes posterior/distal to the mesiobuccal groove of the lower first molar.