Occlusion

Question 1

Normal occlusion

Answer 1

Mesognathic facial profile.
Molars: mesiobuccal cusp of maxillary first molar occludes with buccal groove of mandibular first molar
Canines: maxillary canine occludes with distal half of mandibular canine and mesial half of mandibular first premolar

Question 2

Class I malocclusion or neutroclusion

Answer 2

molar and canine relationships are similar to normal, may have crowded alignment of anterior teeth, protruded or retruded maxillary incisors, anterior or posterior crossbite, mesial drift of molars

Question 3

Class II malocclusion or distoclusion

Answer 3

Retrognathic facial profile.
Molars: buccal groove of mandibular first molar is distal to mesiobuccal cusp of maxillary first molar by at least width of a premolar
Canines: distal surface of mandibular canine is distal to mesial surface of maxillary canine by at least width of a premolar
When distance is less than the width of a premolar, the relation can be classified as TENDENCY toward Class II.
Class II, division I: mandible is retruded, all maxillary incisors are protruded, “flipped up”
Class II, division II: mandible is retruded, one or more maxillary incisors are retruded, “flipped down”

Question 4

Class III malocclusion or mesioclusion

Answer 4

Prognathic facial profile.
Molars: buccal groove of mandibular first molar is mesial to mesiobuccal cusp of maxillary first molar by at least width of a premolar
Canines: distal surface of mandibular canine is mesial to mesial surface of maxillary canine by at least width of a premolar