INBDE (Integrated National Board Dental Examination) Practice Exam

Cusp-marginal ridge occlusal scheme is seen with class ____.

1. 1

2. 2

3. 3

4. 4

The correct answer is: 1

The cusp-marginal ridge occlusal scheme is seen with class I occlusion. In this occlusal scheme, the functional cusp of the mandibular posterior teeth occludes with the facial embrasure of the maxillary teeth and the marginal ridges are in contact. Class I occlusion is also known as normal occlusion, where the mesiobuccal cusp of the maxillary first molar occludes with the buccal groove of the mandibular first molar. This is the most common occlusion seen in the general population. Classes II, III, and IV are considered malocclusions. Class II is characterized by the distal relationship of the mandibular first molar relative to the maxillary first molar, Class III by the mesial relationship, and Class IV by lack of occlusal contact due to tooth size discrepancies or tooth loss.