- The normal positional relationship of the mandibular central incisors relative to the maxillary central incisors is that the mandibular incisors are positioned lingual to the maxillary incisors.
- This means that the lower central incisors are located slightly behind (towards the tongue side) the upper central incisors when the teeth are in occlusion.

- This relationship is important for proper occlusion and function, allowing efficient cutting and shearing of food during mastication.
- If the mandibular incisors were positioned buccally or edge-to-edge, it could indicate a malocclusion such as an anterior crossbite or edge-to-edge bite, which may require orthodontic intervention.

To summarize:
- The mandibular central incisors are normally positioned lingual to the maxillary central incisors.
- This alignment contributes to a normal overjet and overbite in the anterior segment.
- Proper positioning ensures efficient function and aesthetics in the dental arch.

Reference: Wheeler’s Dental Anatomy, Physiology and Occlusion, 10th Edition, Chapter 8: Occlusion and Articulators, Page 214