Evaluation of inferior alveolar artery and its variations via three-dimensional rotational angiography

The inferior alveolar artery (IAA) is the principal vascular supply to the mandible. Knowledge of mandibular anatomy is crucial when it comes to dental extractions—particularly the removal of impacted third molars—dental implant surgery, cyst-tumor surgery, orthognathic surgery, and procedures such as sagittal split osteotomy. The purpose of this study is to evaluate the branching patterns and topographic characteristics of the IAA in the Turkish population using three-dimensional rotational angiography (3D-RA) and to describe a radiological classification of IAA variations in living cases, in addition to previous cadaver studies and literature review. The study included a cohort of 68 adult patient 34 female and 34 male—with ages ranging from 20 to 78 years, who underwent unilateral or bilateral cerebral and carotid artery 3D-RA imaging through injection of the Common Carotid Artery (CCA). The findings obtained from the study were analyzed using IBM SPSS Statistics 22 software for statistical assessment. The diameters of the internal carotid artery (ICA), external carotid artery (ECA), maxillary artery (MA), and IAA, as well as the course of the MA relative to the lateral pterygoid muscle (MLP), the origin, emergence, shape, and angle of the IAA were measured. The findings were analyzed according to gender, age, and side, and the relationships between the findings were evaluated. A modified classification was created by referencing the classification established for MA in the literature, and the IAA was classified as straight, curved, or looped based on its shape. The branch of the IAA known as the lingual branch was identified, and its origins were evaluated. It was observed that the ICA, ECA, and MA diameters were significantly thinner in female patients compared to male patients (p: 0.036, p: 0.001, p: 0.001, respectively). There was no statistically significant relationship between the diameter of the inferior alveolar artery (IAA) and gender, age, or side concerning other anatomical structures (p > 0.05). Among the 101 hemi-craniums evaluated in the study, the IAA originated from the maxillary artery in 96 cases (96%), from the external carotid artery in 4 cases (4%), while it was not observed in 1 case. Branching from its origin, the IAA was observed to emerge either as a single vessel or as a trunk with the posterior deep temporal artery (PDTA), with all cases showing the presence of the IAA-PDTA trunk coinciding with a deep course of the MA, consistent with the literature. Additionally, the occurrence of the IAA-PDTA trunk was statistically significantly higher in females in our study (p: 0.028). There was also a positively moderate level of correlation found between the length of the trunk and the diameter of the IAA (p: 0.003). There was a significant relationship observed between the superficial course of the maxillary artery and the origin of the lingual branch (p: 0.001). Three-dimensional rotational angiography imaging provides valuable information in vascular anatomical studies due to its submillimetric evaluation and detailed measurements. In this context, more detailed measurements with 3D-RA imaging in procedures involving the IAA and associated anatomical structures will guide important points to be determined before surgical procedures, thus reducing the rate of complications. Further vital studies are needed to define topographic or radiological points more precisely.