Topographic and anatomical justification of safe zones for local anesthesia based on the study of the microcirculatory bed and craniotype

Objective. To present a topographic and anatomical characterization of the mucous membrane of the alveolar regions of the jaws and the vascular architecture of the submucosal layer in relation to cranial and facial shape, based on a study of unfixed head specimens from adult individuals. Material and methods. The study was conducted on 21 unfixed head specimens of adults aged 28—75 years. External carotid artery cannulation, contrast enhancement of the vascular bed using silicone mass, layered dissection, and craniometry (cranial and facial indices) were performed. A semi-quantitative scale was used to assess microcirculatory density in the cervical, interradicular, and periapical regions: 0% (absence), 50% (single vessels not throughout), 74% (single vessels throughout), and 100% (dense network with anastomoses). Results. Distribution by cranial index was as follows: brachycrania — 10 (47.6%), mesocrania — 5 (23.8%), dolichocrania — 6 (28.6%). In all cases, a narrow facial morphotype was observed (facial index 119.42±8.37). It was established that in brachycranial and dolichocranial specimens, the periapical region is characterized by maximal vascular density (100% — dense network with anastomoses), whereas in the cervical region and interradicular spaces, vessels are represented by single trunks (74%). In mesocranial specimens, a more uniform distribution was observed (74—100%). Conclusions. In patients with brachycrania and dolichocrania, the cervical region and interradicular spaces are relatively safe zones for submucosal infiltration anesthesia.