INBDE (Integrated National Board Dental Examination) Practice Exam

The option B is correct because, in general, the D slope refers to the distal (back) slope of a tooth and the M slope refers to the mesial (front) slope of a tooth. The maxillary (upper) teeth have a larger and deeper D slope than the mandibular (lower) teeth. However, there are exceptions, such as the primary maxillary canine and permanent maxillary premolar, which have a smaller D slope compared to the M slope. This is because the primary maxillary canine is a smaller tooth and the permanent maxillary premolar has a more equal D and M slope. Therefore, for these specific teeth, the D slope is not greater than the M slope, unlike the majority of other teeth. This is why the other options are incorrect as they do not have this exception.