15 Pages in Head & Neck Anatomy

What are the two layers of oral mucosa?

Epithelium (stratified squamous epithelium) and connective tissue (lamina propria)

What separates epithelium from lamina propria?

Basement membrane

What does the basement membrane become in a developing tooth?

DEJ (dentinoenamel junction)

What type of epithelium is found in masticatory mucosa?

Keratinized stratified squamous epithelium

Where is masticatory mucosa found?

Gingiva and hard palate

Is lining mucosa usually keratinized?

No

Does lining mucosa have a submucosa?

Yes

Where is lining mucosa found?

Buccal mucosa, labial mucosa, floor of mouth, soft palate, alveolar mucosa, vestibular mucosa

Where is specialized mucosa located?

Dorsum (top) of the tongue

What structures are found in specialized mucosa?

4 types of papillae

What two embryonic processes form most oral cavity structures?

Frontal process and 1st branchial arch

What does the frontal process form?

Forehead and frontal bone

What does the median nasal process form?

Center and tip of nose, nasal septum

What does the globular process form?

Philtrum and premaxillary palate

What does the lateral nasal process form?

Sides of nose and infraorbital areas

What is the percent mineralization of enamel?

96%

What is the hardest tissue in the body?

Enamel

What cells produce enamel?

Ameloblasts

Where do ameloblasts come from?

Inner enamel epithelium

What are lines of Retzius?

Incremental lines from mineralization

What are enamel spindles?

Ends of odontoblastic processes crossing the DEJ

What is the percent mineralization of dentin?

70%

What makes up the bulk of the tooth?

Dentin

What cells produce dentin?

Odontoblasts

Where do odontoblasts originate from?

Dental papilla

When is primary dentin deposited?

Before completion of the tooth root

What is mantle dentin?

First layer of dentin adjacent to DEJ

What fibers are found in mantle dentin?

Korff's fibers (thick collagen)

What is circumpulpal dentin?

Remainder of dentin

When does secondary dentin develop?

After crown is in occlusion

What do dentinal tubules contain?

Odontoblastic processes

Why does dentin sensitivity occur?

Fluid movement in dentinal tubules

What type of tissue is pulp?

Soft, loose connective tissue

Pulp develops from what?

Dental papilla of tooth germ

What does pulp contain?

Fibroblasts, odontoblasts, histiocytes, blood vessels, nerves, pulp stones

What is the percent mineralization of cementum?

50% (same as bone)

Where is cementum located?

Root surface

Cementum develops from what?

Dental sac of tooth germ

What cells produce cementum?

Cementoblasts (located in PDL)

What cells are found in cementum lacunae?

Cementocytes

Where is cementum thinnest?

Cervical area

Where is cementum thickest?

Apex

Where does cementum get nourishment?

Periodontal ligament (PDL)

What are the muscles of mastication?

Masseter, temporalis, medial pterygoid, lateral pterygoid

What nerve innervates the muscles of mastication?

Trigeminal nerve (Mandibular division V3)

What innervates the sternocleidomastoid and trapezius muscles?

Accessory nerve (XI)

What nerve innervates the muscles of facial expression?

Facial nerve (VII)

What are examples of facial expression muscles?

Orbicularis oculi, orbicularis oris, buccinator, zygomatic major/minor, mentalis, risorius, platysma, corrugator, procerus

What innervates the levator palpebrae superioris?

Oculomotor nerve (III)

What are the intrinsic tongue muscles?

Superior/inferior longitudinal, transverse, vertical

What are the extrinsic tongue muscles?

Genioglossus, hyoglossus, styloglossus

What nerve innervates most tongue muscles?

Hypoglossal nerve (XII)

What innervates the palatoglossus?

Vagus nerve (X)

What innervates the pharyngeal constrictors?

Vagus nerve (X)

What innervates the stylopharyngeus?

Glossopharyngeal nerve (IX)

What innervates the tensor veli palatini?

Trigeminal nerve (V3)

What innervates the digastric muscle?

V3 & VII

What innervates the mylohyoid?

V3

What innervates the stylohyoid?

Facial nerve (VII)

What innervates the geniohyoid?

C1 (1st cervical nerve)

What innervates the infrahyoid muscles?

C2 & C3 (2nd and 3rd cervical nerves)