Oral Cavity

29 April 2010

Sensory Innervation of Oral Cavity

Facial n. (VII) taste to anterior 2/3rds of tongue (only to taste buds)

Maxillary branch of Trigeminal n. (V2) - upper teeth and roof of mouth

Mandibular branch of Trigeminal n. (V3) - tongue, floor of mouth and lower teeth

Glossopharyngeal n. (XI) - general sensation and taste to posterior 1/3rd of tongue and general sensation to oropharynx

see Netter, 2003 pl. 58; Netter, 2006 pl. 62

 

Important branches of maxillary n.

      Zygomatic

      Infraorbital

Nasopalatine

      Greater palatine

      Lesser palatine

      Superior alveolar

Woodburne & Burkel, 1988, Fig. III-72

 

Important branches of mandibular n.

Auriculotemporal n.    

Branches to masseteric mm., tensor veli palatini, buccal branch

      Lingual n.

      Mylohyoid n.

      Inferior alveolar n.

Woodburne & Burkel, 1988, Fig. III-52

 

Facial nerve (VII) - branches to mouth travel with the Lingual n.

Chorda tympani

  Taste to anterior 2/3rds of  tongue

Submandibular gang.

  Parasympathetic innervation to submandibular & sublingual glands

Netter, 2003 pl. 117; Netter 2006 pl. 123

 

Surface features of oral cavity

Hard palate

Soft palate

Uvula

Palatoglossal arch

Palatopharyngeal arch

Dorsum of Tongue

see Netter, 2003 pl. 47; Netter, 2006 pl. 51

 

Innervation and blood supply of mouth

      Greater palatine a. & n.

      Greater palatine for.

      Lesser palatine a. & n.

      Palatoglossus m.

      Palatopharyngeus m.

Netter, 2003 pl. 48; Netter, 2006 pl. 52

 

Tongue in sagittal section

The root "geni" -  G. chin or jaw (“ment” – L., the chin; basis for mental nerve, mental process, etc.)

Genioglossus m.

Geniohyoid m.

Mylohyoid m.

Hyoid bone

see Netter, 2003 pl. 59; Netter, 2006 pl. 63

muscles on lateral side of tongue

Palatoglossus m.

Styloglossus m.

Stylohyoid m.

Hyoglossus m.

other lateral structures:

   Submandibular duct

   Lingual a. & v.

   Hypoglossal n. - motor innervation to intrinsic muscles of tongue and genioglossus

Netter, 2003 pl. 55; Netter, 2006 pl. 59

 

Suprahyoid Muscles in an Inferolateral view

Mylohyoid

Digastric

  anterior

  posterior

Stylohyoid

Infrahyoid strap mm.

Netter, 2003 pl. 49; Netter, 2006 pl. 53

 

Swallowing

Occurrs in three stages

• 1. Tongue pushes food bolus backward from mouth into oropharynx.

• 2. Elevation of soft palate seal nasopharynx and deflect bolus inferiorly; suprahyoid and strap muscles contract to elevate larynx.

• 3. Sequential contraction of pharyngeal constrictors.  Peristaltic contractions of esophagus propel bolus inferiorly

See Moore & Dalley, pp. 1104-1105

 

Teeth

• Composed of a base of dentin

– Bone-like, but with no living cells

• Roots in alveoli of maxilla & mandible

• Roots covered by cementum

• Held in alveoli by periodontal ligament

• Pulp cavity contains nerves, blood vessels & living cells

• Crown covered by enamel

• Four types of teeth

 

• Incisors

– Two per quadrant

– Thin cutting edge

• Canines

– One per quadrant

– Single cone for piercing

• Premolars

– Two per quadrant

– Two cusps

• Molars

– Three cusps per quadrant

– Three or more cusps for grinding

Netter, 2003, pl. 52; Netter, 2006 pl. 56

 

Innervation of Teeth

Maxillary n.

  superior alveolar nn.

Mandibular n.

  inferior alveolar n.

see Netter, 2003 pls. 41, 42; Netter, 2006 pls. 45, 46

 

Reference

Woodburne, R.T. & W.E. Burkel, 1988. Essentials of Human Anatomy. 8th ed. Oxford University Press