Since Dunn et al. (1996), performed dissections on 25 cadaveric specimens of human heads in 1996 and discovered a fifth cranial masticatory muscle, which they called the sphenomandibular muscle (SMM), a debate has arisen as to whether it is really an independent muscle or a deep fasciculus of the tempo- ral bone. On the other hand, the common description of the sphenoid bone overlooks an inconstant structure called the sphenoid tubercle (ST), which Dunn et al. (1996), describe as the origin of the sphenomandibular joint. Several studies have investigated these structures independently, but to date, no study has explored the relationship between the independence of the SMM and the ST, therefore, the aim of this study was to analyze and establish the relationship between the presence of the ST with the origin of the SMM. In order to establish a relationship between these two structures, 12 cadaveric specimens of human hemiheads were used. In situ dissections were performed to identify the SMM and tomography scans were performed for the ST. Of the 12 hemiheads, 8 showed an independent presence of the MEM next to the ST (p=0.018). Conclusion: It is concluded that there could be a possible relationship between the presence of the ST and the origin of the MEM.

KEY WORDS: Anatomical variation; Temporal muscle; Sphenoid bone; Temporomandibular joint; Mastication.