In 1925, Colp classified dermoid cysts according to their relationship with the surrounding muscles as sublingual beyond the geniohyoid muscle, geniohyoid between geniohyoid and
mylohyoid muscles and lateral beneath the
mylohyoid muscle [8, 9].
The sublingual and submental arteries go parallel along the surface of
mylohyoid muscle: the first one medially and superiorly to the surface muscle and the second one laterally and inferiorly to the surface muscle.
However, the
mylohyoid muscle has not been activated early on in relation to the other and of the geniohyoid muscle there was not part of this complex.
The mylohyoid nerve is a branch of the inferior alveolar nerve (IAN); it courses anteroinferiorly in a groove on the medial aspect of the mandibular ramus to supply the
mylohyoid muscle and the anterior belly of the digastric muscle.
Within the floor of mouth, the term ranula may be applied to mucin which dissects into the
mylohyoid muscle, resulting in chin or upper neck swelling (rana in Latin means frog, and ranula is used since it looks like a frog's underbelly clinically).
The sublingual space (SLS) is located inferior to intrinsic muscles of the oral tongue, lateral to the genioglossus-geniohyoid complex and superomedial to the
mylohyoid muscle. Anteriorly, it is related to the mandible.
T-2 weighed MRI images, showed hyperintense fluid filled cavity in left sublingual space, extending to right submandibular space along the posterior edge of
mylohyoid muscle. Under general anesthesia, an incision was made in the right lingual vestibule, and excision of the lesion along with extirpation of the right sublingual gland was performed.
The roots of mandibular second and third molar teeth lie below the attachment of the
mylohyoid muscle to the mandible and infection from these teeth spread to the submandibular space.
The base of this space is composed of loose connective tissue located between the superficial layer of the deep cervical fascia and the
mylohyoid muscle. The boundaries of the submental space are formed by the hyoid bone inferiorly, the mandible superiorly, and the anterior bellies of the digastric muscles bilaterally (figure).
Ranulas are classified as either "simple" and confined to the sublingual space, or as "plunging" with extension through the floor of mouth and below the
mylohyoid muscle. The plunging variety presents as a cystic mass centered within the submandibular space (Figure 8).
It contains the submandibular gland, submandibular lymph nodes, facial vein, hypoglossal nerve, nerves and vessels for the
mylohyoid muscle and the carotid sheath, which contains the external and internal carotid arteries, internal jugular vein and vagus nerve.
A curved artery forceps was passed through the submental incision and then through subcutaneous layer, platysma,
mylohyoid muscle, sub mucosa and oral mucosa.