Precise extratemporal pattern and intramuscular distribution of the facial nerve

Abstract

An arborization of the branches of the facial nerve has the most complexity and variability. Moreover, knowledge of the facial nerve has great importance for surgical and non-surgical interventions in the face region. However, few studies have attempted to determine the entire course and pattern of terminal branching of the facial nerve in the extratemporal and intramuscular parts of the face. Therefore, the purpose of this study was to investigate the precise detail of the facial nerve in extratemporal and intramuscular parts. This study was conducted in forty-two hemifaces of embalmed cadavers by conventional dissection, fourteen hemi-faces of embalmed cadavers by histological study, and sixteen hemi-faces of soft cadavers by Sihler’s staining technique to investigate the characteristics of the branches of the facial nerve. The results revealed that the mean number of the temporal, zygomatic, buccal, marginal mandibular, and cervical branches of the facial nerve were 2.57 ±0.83, 1.83 ±0.69, 3.10 ±0.82, 1.36 ±0.49, and 1.07 ±0.26 branches respectively. The branches of the facial nerve were distributed deep to the parotido-masseteric fascia, temporo-parietal fascia, superficial musculo-aponeurotic system, and platysma muscle depending on each branch of the facial nerve. In conclusion, a caution area of each branch of the facial nerve should be carefully performed based on intensive nerve distribution to prevent complications and unexpected outcomes.