Dental OSCE (Objective Structured Clinical Examination) Practice Exam

Which cusp of the maxillary molars occludes with the central fossa of the opposing mandibular molars?

1. DB cusp

2. MB cusp

3. Distal cusp

4. ML cusp

The correct answer is: ML cusp

The medial lingual cusp of the maxillary molar plays a crucial role in occlusion with the central fossa of the opposing mandibular molar. This is due to the overall morphology and positioning of the upper and lower molars. The maxillary molars typically have a larger medial lingual cusp that extends farther down into the oral cavity, allowing it to fit neatly into the central fossa of the mandibular molars. This relationship is significant for maintaining a proper occlusal relationship and ensuring effective mastication. The occlusal contacts also contribute to the stability of the dental arch. The central fossa itself is a critical area for establishing balanced occlusion, serving as a key point of contact during the chewing cycle. The other cusps of the maxillary molars have different occlusal relationships and do not make contact with the central fossa of the mandibular molars in the same way. For instance, the distobuccal cusp primarily occludes with the crest of the marginal ridge of the opposing mandibular molars, while the mesiobuccal cusp typically contacts the distal marginal ridge area. Understanding these specific occlusal relationships is essential for effective dental practice and to promote long-term dental health.