Mylohyoid herniation: gross and histologic evaluation with clinical correlation.

The purpose of this study was to further document the presence of a mass herniating inferiorly through the mylohyoid muscle into the submandibular area, to identify the mass histologically, and to discuss its importance in a differential diagnosis of masses in this area. A mass that perforated the mylohyoid muscle was found in 45 of the 100 cadavers studied. These 45 cadavers contained a total of 63 herniations. Of the 60 male cadavers, 26 (43.33%) showed herniation, and 19 (47.50%) of the 40 female cadavers showed herniation. Histologic evaluation of the 63 biopsy specimens revealed the following: 30 herniating masses (47.61%) were of the sublingual gland; 28 (44.44%) were of the submandibular gland; 4 (6.34%) were composed of pure adipose tissue, and 1 (1.58%) was a cholesteatoma. Inflammation was found in 46 (73.00%) of the biopsy specimens, consisting of sclerosing sialoadenitis in 30 specimens (47.61%) and a mild chronic inflammatory infiltrate in 16 specimens (25.39%).