Objective The aim of this study was to evaluate the angiosome of the superior and inferior labial arteries within the superior and inferior labia and to describe superior and inferior labial musculomucosal axial pattern flaps that can be used for intra-oral wound reconstruction. This study also presents the clinical use of a superior labial musculomucosal flap in a dog. Materials and MethodsThe common carotid arteries of six canine cadavers were injected with barium sulphate. The skin of the face and labial mucosa was removed and radiographed to study the vascular supply of the superior and inferior labia. ResultsThe angiograms in all dogs demonstrated that the superior and inferior labial arteries were located within the musculomucosal layer of the labia. At the junction of the rostral and caudal half of the upper lip, extensive choke anastomoses joined the angiosome of the infra-orbital artery. The inferior labial artery perfused the caudal half of the lower labium and had extensive choke anastomoses with the middle and rostral mental arteries. Clinical Significance The musculomucosal flaps of the superior and inferior labia contain a rich arterial blood supply, which suggests that these flaps may survive in live dogs. The superior labial musculomucosal flap was successfully used to reconstruct a large cleft palate in a single clinical case.