Morphometry of the masseter muscle and topographic location of the masseteric nerve: anatomical study in terms of BTX-A and facial reanimation applications

Year 2025, Volume: 7 Issue: 2, 126 - 131, 21.03.2025

Ayla Tekin , Hüma Kaçar , Nurşen Zeybek

https://doi.org/10.38053/acmj.1610659

Abstract

Aims: The aim of this study was to investigate the morphometry of the masseter muscle (MM) and the topography of the masseteric nerve (MN) innervating the MM.
Methods: The MM and MN were examined on 18 sides (female: 4, male: 5) of formaldehyde-fixed adult cadavers in the laboratory of Kocaeli University Faculty of Medicine, Department of Anatomy. The MM and its surroundings were exposed by dissection. The morphometric measurements of the MM were obtained using a digital caliper. Tragus and lateral canthus landmarks were used for the location of the motor nerve of the MM.
Results: In this study, morphometric measurements of the MM were presented. A statistically significant difference was found between sexes in morphometric measurements related to the height and width of the muscle (p<0.05). MM thickness was measured as 6.47 (6.06-6.50) mm. The median value of the distance between the tragus and lateral canthus was 76.04 (72.36-79.02) mm. Accordingly, the branching point of the MN; the vertical distance from the midpoint of the distance between the tragus and lateral canthus to the nerve was 42.72 (39.09-44.50) mm.
Conclusion: We believe that determining the topographic location of the MN using standard anatomical landmarks will make important contributions to both facial reanimation and BTX-A applications.

Keywords

Masseter muscle, masseteric nerve, facial reanimation, botulinum toxin type A, masseter muscle hypertrophy

References

• Almukhtar RM, Fabi SG. The masseter muscle and its role in facial contouring, aging, and quality of life: a literature review. Plast Reconstr Surg. 2019;143(1):39E-48E. doi:10.1097/PRS.0000000000005083
• Ayhan M, Işler SC, Kasapoglu C. Combination of medical and surgical treatments for masseter hypertrophy. Case Rep Dent. 2018;2018:7168472. doi:10.1155/2018/7168472
• Ganapathy A, Kumar V, Prathapamchandra V, et al. Topographic localization of nerve to masseter muscle to determine the primary nerve-muscle relation, an aid to facial sculpting techniques. Muscles Ligaments Tendons J. 2020;10(1):124-129. doi:10.32098/mltj.01.2020.17
• Nikolis A, Enright KM, Masouri S, Bernstein S, Antoniou C. Prospective evaluation of incobotulinumtoxina in the management of the masseter using two different injection techniques. Clin Cosmet Investig Dermatol. 2018;11:347-356. doi:10.2147/CCID.S164848
• Murphey AW, Clinkscales WB, Oyer SL. Masseteric nerve transfer for facial nerve paralysis a systematic review and meta-analysis. JAMA Facial Plast Surg. 2018;20(2):104-110. doi:10.1001/jamafacial.2017.1780
• Hontanilla B, Diego Marré. Comparison of hemihypoglossal nerve versus masseteric nerve transpositions in the rehabilitation of short-term facial paralysis using the facial clima evaluating system. Plast Reconstr Surg. 2012;130(5):662e-672e. doi:10.1097/PRS.0b013e318267d5e8
• Spira M. Anastomosis of masseteric nerve to lower division of facial nerve for correction of lower facial paralysis. Preliminary report. Plast Reconstr Surg. 1978;61(3):330-334. doi:10.1097/00006534-197803000-00004
• Bianchi B, Ferri A, Ferrari S, Copelli C, Salvagni L, Sesenna E. The masseteric nerve: a versatile power source in facial animation techniques. Br J Oral Maxillofac Surg. 2014;52(3):264-269. doi:10.1016/j.bjoms.2013.12.013
• Urban MJ, Eggerstedt M, Varelas E, et al. Hypoglossal and masseteric nerve transfer for facial reanimation: a systematic review and meta-analysis. Facial Plast Surg Aesthet Med. 2022;24(1):10-17. doi:10.1089/FPSAM.2020.0523
• Manktelow RT, Tomat LR, Zuker RM, Chang M. Smile reconstruction in adults with free muscle transfer innervated by the masseter motor nerve: effectiveness and cerebral adaptation. Plast Reconstr Surg. 2006; 118(4):885-899. doi:10.1097/01.prs.0000232195.20293.bd
• Henstrom DK. Masseteric nerve use in facial reanimation. Curr Opin Otolaryngol Head Neck Surg. 2014;22(4):284-290. doi:10.1097/MOO. 0000000000000070
• Ketel EC, de Wijk RA, de Graaf C, Stieger M. Relating oral physiology and anatomy of consumers varying in age, gender and ethnicity to food oral processing behavior. Physiol Behav. 2020;215:112766. doi:10.1016/j.physbeh.2019.112766
• Park S, Shin WS. Differences in eating behaviors and masticatory performances by gender and obesity status. Physiol Behav. 2015;138:69-74. doi:10.1016/j.physbeh.2014.10.001
• Lee JY, Kim JN, Yoo JY, et al. Topographic anatomy of the masseter muscle focusing on the tendinous digitation. Clin Anat. 2012;25(7):889-892. doi:10.1002/ca.22024
• Rani S, Ravi MS. Masseter muscle thickness in different skeletal morphology: an ultrasonographic study. Indian J Dent Res. 2010;21(3): 402-407. doi:10.4103/0970-9290.70812
• Soyoye OA, Otuyemi OD, Kolawole KA, Ayoola OO. Relationship between masseter muscle thickness and maxillofacial morphology in pre-orthodontic treatment patients. Int Orthod. 2018;16(4):698-711. doi: 10.1016/j.ortho.2018.09.015
• Duráo APR, Morosolli A, Brown J, Jacobs R. Masseter muscle measurement performed by ultrasound: a systematic review. Dentomaxillofac Radiol. 2017;46(6):20170052. doi:10.1259/dmfr. 20170052
• Raadsheer MC, van Eijden TMGJ, van Spronsen PH, van Ginkel FC, Kiliaridis S, Prahl-Andersen B. A comparison of human masseter muscle thickness measured by ultrasonography and magnetic resonance imaging. Arch Oral Biol. 1994;39(12):1079-1084. doi:10.1016/0003-9969 (94)90061-2
• Uchida Y, Motoyoshi M, Shigeeda T, et al. Relationship between masseter muscle size and maxillary morphology. Eur J Orthod. 2011;33(6):654-659. doi:10.1093/ejo/cjq152
• Rauso R, Lo Giudice G, Tartaro G, Zerbinati N, Nicoletti GF, Fragola R. Botulinum toxin type A injections for masticatory muscles hypertrophy: a systematic review. J Craniomaxillofac Surg. 2022;50(1):7-18. doi:10.1016/j.jcms.2021.09.019
• Kundu N, Kothari R, Shah N, et al. Efficacy of botulinum toxin in masseter muscle hypertrophy for lower face contouring. J Cosmet Dermatol. 2022;21(5):1849-1856. doi:10.1111/jocd.14858
• Hu KS, Kim ST, Hur MS, et al. Topography of the masseter muscle in relation to treatment with botulinum toxin type A. Oral Surg Oral Med Oral Pathol Oral Radiol Endod. 2010;110(2):167-171. doi:10.1016/j.tripleo.2009.12.036
• Kim NH, Park RH, Park JB. Botulinum toxin type A for the treatment of hypertrophy of the masseter muscle. Plast Reconstr Surg. 2010;125(6): 1693-1705. doi:10.1097/PRS.0b013e3181d0ad03
• Von Lindern JJ, Niederhagen B, Appel T, Bergé S, Reich RH. Type A botulinum toxin for the treatment of hypertrophy of the masseter and temporal muscles: an alternative treatment. Plast Reconstr Surg. 2001; 107(2):327-332. doi:10.1097/00006534-200102000-00004
• Sforza C, Tarabbia F, Mapelli A, et al. Facial reanimation with masseteric to Facial nerve transfer: a three-dimensional longitudinal quantitative evaluation. J Plast Reconstr Aesthet Surg. 2014;67(10):1378-1386. doi:10.1016/j.bjps.2014.05.039
• Jandali D, Revenaugh PC. Facial reanimation: an update on nerve transfers in facial paralysis. Curr Opin Otolaryngol Head Neck Surg. 2019;27(4):231-236. doi:10.1097/MOO.0000000000000543
• Kollar B, Weiss JBW, Kiefer J, Eisenhardt SU. Functional outcome of dual reinnervation with cross-facial nerve graft and masseteric nerve transfer for facial paralysis. Plast Reconstr Surg. 2024;153(6):1178E-1190E. doi:10. 1097/PRS.0000000000010888
• Cotrufo S, Hart A, Payne AP, Sjogren A, Lorenzo A, Morley S. Topographic anatomy of the nerve to masseter: an anatomical and clinical study. J Plast Reconstr Aesthet Surg. 2011;64(11):1424-1429. doi: 10.1016/j.bjps.2011.05.026
• Copelli C, Manfuso A, Aragona T, Cama A, Topazio D, Hirt B. Anatomic landmarks for masseteric nerve identification: anatomic study for a new reference point. J Plast Reconstr Aesthet Surg. 2021;74(5):1101-1160. doi: 10.1016/J.BJPS.2020.10.074
• Kaya B, Apaydin N, Loukas M, Tubbs RS. The topographic anatomy of the masseteric nerve: a cadaveric study with an emphasis on the effective zone of Botulinum toxin a injections in masseter. J Plast Reconstr Aesthet Surg. 2014;67(12):1663-1668. doi:10.1016/j.bjps.2014.07.043