The distobuccal cusp of the mandibular first molar occupies the embrasure between the maxillary second premolar and first molar. Which Angle Class does this describe?

• A. Angle Class I
• B. Angle Class II
• C. Angle Class III
• D. Mandibular Movements

Answer: (C)

The key idea is the relative position of the jaws in the posterior teeth. In Angle’s system, a Class III relationship means the mandible is forward (prognathic) relative to the maxilla, so the lower posterior teeth occlude ahead of the upper posterior teeth. When the distobuccal cusp of the mandibular first molar sits in the embrasure between the maxillary second premolar and first molar, it shows the lower arch is advancing anteriorly compared with the upper arch. That forward mandibular position is the hallmark of Class III malocclusion. In contrast, a Class II pattern would have the upper teeth ahead or the lower teeth positioned posteriorly, and Class I would show a normal, harmonious molar relationship.