Related Experiment Video
Updated: Jan 29, 2026
19:53
Single-stage Dynamic Reanimation of the Smile in Irreversible Facial Paralysis by Free Functional Muscle Transfer
Published on: March 1, 2015
106.5K
Mapping the Masseteric Nerve for Facial Reanimation: An Anatomical Study of Two Dissection Strategies
Stefan Rössler1,2, Wolfgang Zemann3, Niels Hammer1,4,5
1Division of Macroscopic and Clinical Anatomy, Gottfried Schatz Research Center, Medical University of Graz, Auenbruggerplatz 25, A-8036 Graz, Austria.
Medicina (Kaunas, Lithuania)
|January 28, 2026
Summary
The masseteric nerve (Mn) is crucial for facial reanimation. This study defines precise anatomical landmarks, the angle-canthus line (ACL) and articular eminence line (AEL), to guide safe surgical dissection of the Mn.
Area of Science:
- Anatomy
- Neurosurgery
- Facial Surgery
Background:
- The masseteric nerve (Mn) is vital for facial reanimation due to its accessibility and effectiveness.
- Precise anatomical knowledge is essential for safe Mn dissection during surgical procedures.
- Current understanding of the Mn's intramuscular topography relative to landmarks needs refinement.
Purpose of the Study:
- To investigate the intramuscular position of the masseteric nerve (Mn).
- To define reliable intraoperative reference lines for Mn dissection.
- To improve the safety and reproducibility of facial reanimation surgeries involving the Mn.
Main Methods:
- Postmortem examination of 72 hemicrania from 36 Thiel-embalmed cadavers.
- Measurements referenced to the angle-canthus line (ACL) and articular eminence line (AEL).
- Analysis of Mn course, branching patterns, and relationship to reference lines within the masseter muscle (Mm).
Main Results:
- The Mn crossed the ACL at 39.9 ± 5.9 mm from the mandibular angle, with branches emerging superior to the ACL.
- The Mn coursed 4.9 ± 1.9 mm anterior to the articular eminence and 4.7 ± 1.5 mm inferior to the AEL.
- The AEL and ACL proved reliable for locating the Mn, with a predictable oblique course within the Mm.
Conclusions:
- The masseteric nerve (Mn) can be reliably located using the AEL and ACL, improving intraoperative precision.
- ACL-based access may preserve critical nerve branches, reducing donor site morbidity.
- This anatomical mapping offers a potential alternative for smile reconstruction, particularly in patients with intact eye closure.
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