- The forehead is formed by the smooth, broad, convex plate of bone called the frontal squama.
- In foetal skulls, the halves of the frontal squama are divided by a metopic suture.
- In most people, the halves of the frontal bone begin to fuse during infancy and the suture between is usually not visible after 6 years of age.
- The frontal bone forms the thin roof of the orbits (eye sockets).
- Just superior to and parallel with each supraorbital margin is a bony ridge, the superciliary arch, which overlies the frontal sinus. This arch is more pronounced in males.
- Between these arches there is a gently, rounded, medial elevation called the gabella; this term derives from the Latin word glabellus meaning smooth and hairless. In most people, the skin over the gabella is hairless.
-The slight prominences of the forehead on each side, superior to the superciliary arches, are called frontal eminences (tubers).
- The supraorbital foramen (occasionally a notch), which transmits the supraorbital vessels and nerve is located in the medial part of the supraorbital margin.
- The frontal bone articulates with the two parietal bones at the coronal suture.
-It also articulates with the nasal bones at the frontonasal suture. At the point where this suture crosses the internasal suture in the medial plane, there is an anthropological landmark called the nasion . The depression is located at the root of the nose, where it joins the cranium.
- The frontal bone also articulates with the zygomatic, lacrimal, ethmoid, and sphenoid bones.
In about 8% of adult skulls, a remnant of the inferior part of the metopic (interfrontal) suture is visible. It may be mistaken in radiographs for a fracture line by inexperienced observers.
- The superciliary arches are relatively sharp ridges of bone and a blow to them may lacerate the skin and cause bleeding.
- Bruising of the skin over a superciliary arch causes tissue fluid and blood to accumulate in the surrounding connective tissue, which gravitates into the upper eyelid and around the eye. This results in swelling and a "black eye".
- Compression of the supraorbital nerve as it emerges from its foramen causes considerable pain, a fact that may be used by anaesthesiologists and anaesthetists to determine the depth of anaesthesia and by physicians attempting to arouse a moribund patient.

Internal Ear

• Osseous labyrinth: a complex system of cavities in the substance of the petrous bone.
• Membranous labyrinth: filled with endolymph, bathed in perilymph.

• This is the second cranial nerve (CN II) and is the nerve of sight.

A. Anatomic position-erect body position with the arms at the sides and the palms  upward

B. Plane or section

1. Definition-imaginary flat surface formed by an extension through an axis

2. Median plane-a vertical plane. that divides a body into right and left halves

3. Sagittal plane

• Any plane parallel to the median plane
• Divides the body into right and left portions

4. Frontal plane

• Vertical plane that forms at right angles to the sagittal plane
• Divides the body into anterior and posterior sections
• Synonymous with the term coronal plane

5. Transverse plane

• Horizontal plane that forms at right angles to the sagittal and frontal planes
• Divides the body into upper and lower portions
• Synonymous with the term horizontal plane

C. Relative positions

1. Anterior

• Nearest the abdominal surface and the front of the body
• Synonymous with the term ventral
• In referring to hands and forearms, the terms palmar and Volar are used

2. Posterior

• Back of the body
• Synonymous with the term dorsal

3. Superior

• Upper or higher
• Synonymous with the term cranial (head)

4. Inferior

• Below or lower
• Synonymous with the term caudal (tail)
• In referring to the top of the foot and the sole of the foot. the terms dorsal and plantar are used respectively

5. Medial-near to the median plane

6. Lateral-farther away from the median plane

7. Proximal-near the source or attachment

8. Distal-away from the source or. attachment

9. Superficial-near the surface

10. Deep-away from the surface

11. Afferent-conducting toward a structure

12. Efferent-conducting away from a structure

The Pharynx

• The pharynx is the continuation of the digestive system from the oral cavity.
• It is a funnel-shaped fibromuscular tube that is the common route for both food and air.
• The pharynx is located posterior to the nasal and oral cavities, and the larynx.

• For the convenience of description, the pharynx is divided into three parts: (1) the nasopharynx, posterior to the nose and superior to the soft palate; (2) the oropharynx, posterior to the mouth; and (3) the laryngopharynx, posterior to the larynx.

• The pharynx is about 15 cm long.
• It extends from the base of the skull to the inferior border of the cricoid cartilage anteriorly, and to the inferior border of C6 vertebra posteriorly.
• It is widest (about 5 cm) opposite the hyoid bone and narrowest (about 1.5) at its inferior end, where it is continuous with the oesophagus.

• The posterior wall of the pharynx lies against the prevertebral fascia, with the potential retropharyngeal space between them.

Superior Constrictor Muscle

• Origin: Hamulus, pterygo-mandibular raphe, and mylohyoid line of the mandible.
• Insertion: Median raphe of the pharynx.
• Nerve Supply: Vagus nerve via the pharyngeal plexus.
• Arterial Supply: Ascending pharyngeal artery, ascending palatine artery, tonsillar branch of the facial artery, and dorsal branch of the lingual artery.
• Action: Constricts the wall of the pharynx during swallowing.