The described molar relationship where the mesiobuccal cusp of the maxillary first molar is mesial to the buccal groove of the mandibular first molar corresponds to which Class?

The described molar relationship where the mesiobuccal cusp of the maxillary first molar is mesial to the buccal groove of the mandibular first molar corresponds to which Class?

• A. End-to-end
• B. Class II
• C. Class I
• D. Class III

Answer: (B)

In this type of question, the key idea is how the upper and lower first molars relate in the sagittal plane, known as Angle’s molar classification. In a normal Class I bite, the mesiobuccal cusp of the upper first molar sits in the buccal groove of the lower first molar. When that upper cusp is positioned mesially to that groove, it means the upper jaw’s molar is ahead of the lower molar, which corresponds to a Class II relationship. The opposite—where the upper cusp is distal to the groove—would describe Class III. So the described arrangement matches Class II.

In this type of question, the key idea is how the upper and lower first molars relate in the sagittal plane, known as Angle’s molar classification. In a normal Class I bite, the mesiobuccal cusp of the upper first molar sits in the buccal groove of the lower first molar. When that upper cusp is positioned mesially to that groove, it means the upper jaw’s molar is ahead of the lower molar, which corresponds to a Class II relationship. The opposite—where the upper cusp is distal to the groove—would describe Class III. So the described arrangement matches Class II.