Cone-beam computed tomographic analysis of the anterior mandible for immediate implant planning

The anterior mandible poses challenges for immediate implant placement due to its limited dimension and proximity to vital structures. This study aimed to assess the three-dimensional configuration of this region using cone-beam computed tomography (CBCT), focusing on sagittal root position (SRP), alveolar bone dimensions, and labial/lingual concavities.

CBCT images from 43 participants (258 teeth) were analyzed. SRP was classified according to Kan's system. Alveolar bone dimension, the location of concavities, and sublingual artery openings were assessed. Comparisons among tooth types and between sides were also performed.

Class I SRP was the most common across all tooth types, whereas Class III was the least. Central incisors showed the greatest labial bone height. Labial bone thickness was consistently < 2 mm, whereas lingual bone width in lateral incisors and canines exceeded 2 mm from the mid-root to the apical region. Labial concavities were highly observed across all tooth types (96.9%), while lingual concavities were rare (5.07%). Canines exhibited the deepest and most apical labial concavities (p < 0.05; p < 0.01, respectively). In addition, sublingual artery openings were most frequently detected in this region (76.8%), most commonly adjacent to the central incisors (53.5%).

The anterior mandible frequently exhibits a predominant Class I SRP, a thin labial bone plate, frequent labial concavities, and sublingual artery openings. A comprehensive preoperative evaluation presents a relevant factor in supporting predictable immediate implant placement in this region.

This study provides detailed three-dimensional data regarding the morphology of the anterior mandible. This insight may serve as a reference to facilitate preoperative immediate implant planning, particularly in determining optimal implant positioning and assessing the potential indication for simultaneous ridge augmentation.