The muscles of the head may be divided into three groups, viz.: (1)
Superficial muscles, including the panniculus and those of the lips,
cheeks, nostrils, eyelids, and external ear; (2) the orbital muscles;
(3) the muscles of mastication.
The =superficial fascia= forms an almost continuous layer, but is very
scanty around the natural orifices. It contains a number of the thin
superficial muscles, so that care must be exercised in removing the
skin. Over the frontal and nasal bones the fascia blends with the
periosteum.
The =deep fascia= is of special interest in three regions. The =temporal
fascia= covers the temporalis muscle, and is attached to the parietal
and frontal crests internally, and to the zygomatic arch externally. The
=buccal fascia= covers the buccinator muscle and the free part of the
outer surface of the ramus of the jaw. Superiorly it is attached to the
facial crest, and posteriorly it forms a band (Ligamentum
pterygomandibulare) which stretches from the hamulus of the pterygoid
bone to the mandible behind the last molar tooth. It is directly
continuous with the =pharyngeal fascia=, which is attached to the great
and thyroid cornua of the hyoid bone, covers the lateral walls of the
pharynx, and blends dorsally with the median raphé of the constrictor
muscles of the latter.