National Board Dental Hygiene Examination (NBDHE) Dental Hygienist Practice Test

What is the smallest permanent tooth in the mouth?

1. Mandibular central incisors

2. Maxillary canine tooth

3. Mandibular lateral incisor

4. Maxillary lateral incisor

The correct answer is: Mandibular central incisors

The smallest permanent tooth in the mouth is represented by the mandibular central incisors. These teeth are typically characterized by their narrow dimensions and are located in the front of the mouth. The central incisors, both maxillary and mandibular, are designed primarily for cutting food; however, the mandibular central incisors are uniquely smaller than their maxillary counterparts as well as other permanent teeth. In dental anatomy, the size parameters of teeth are assessed through various measurements, including mesiodistal width and incisal edge length. The mandibular central incisors usually measure about 5-6 mm in width, making them the smallest of all permanent teeth. This distinction is important in both restorative and orthodontic treatments, where the size and alignment of teeth play critical roles in achieving optimal outcomes. The other choices consist of teeth that are larger in size. The maxillary canine and lateral incisors have broader profiles, contributing to their larger size compared to the mandibular central incisors. This size difference is essential for dental professionals to understand when considering tooth alignment, aesthetic appearance, and functional occlusion.