Oral and Nasal Cavities Flashcards
The floor of the oral cavity is formed by:
The paired mylohyoid muscle, connected in the midline by a raphe
Paired geniohyoid muscles
The tongue
Oral cavity
Roof: hard + soft palate
Floor: muscular diaphragm and tongue
Lateral walls: fascia and skeletal muscle
The oral cavity open anteriorly to:
and posteriorly to:
The oral fissure
Oropharyngeal isthmus
Extrinsic muscles of the tongue
Palatoglossus
Styloglossus
Hyoglossus
Genioglossus
Intrinsic muscles of the tongue
Superior longitudinal
Vertical
Transverse
Inferior longitudinal
Innervation of the tongue
All muscles innervated by hypoglossal nerve, except palatoglossus which is by the vagus
Describe the potential spaces of the oral cavity
1: between mylohyoid and lateral border of hyoglossus
2: between hyoglossus and genioglossus
Structures in the 1st potential space
Lingual nerve
Hypoglossal nerve
Submandibular gland
Lingual vein
Structures in the 2nd potential space
Glossopharyngeal nerve
Lingual artery
Layers that need to be dissected to get to the submandibular gland
Skin
Subcutaneous fat
Periosteum
Investing layer
Three muscles closely related to the submandibular gland
Mylohoid
Hyoglossus
Posterior belly of digastric
Structures than run across the submandibular gland
Facial vein
Facial artery
Lymph nodes
Three nerves at risk during submandibular excision
Marginal mandibular
Lingual nerve
Hypoglossal nerve
Innervation of the tongue
Anterior 2/3 of tongue: special = chorda tympani, general = mandibular nerve
Posterior 1/3: glossopharyngeal nerve
The hard palate
Covered by muscosa
Formed by maxilla and palatine bones
Buccinator
In the same plane as the superior constrictor of the pharynx and together provide continuity between the walls of the oral and pharyngeal cavities
Holds the cheeks against the alveolar arches and keeps food between the teeth when chewing
Facial nerve innervation
5 muscles of the soft palate
Tensor veli palatini Levator veli palatini Palatopharyngeus Palatoglossus Musculus uvulae
Tensor veli palatini
Has 2 parts: a vertical part from the hard palate and a horizontal aponeurosis which it joins with
Tenses soft palate and opens eustachian tube
Levator veli palatini
Arises from petrous part of the temporal bone and eustachian tube
Pulls soft palate up and back to shut off nasopharynx
Palatopharyngeus
Originates from palatine aponeurosis and hard palate
Elevates larynx and pharynx during swallowing
Palatoglossus
Arises from palatine aponeurosis
Helps to elevate the tongue
Musculus uvulae
Passes back from hard palate and fuses with counterpart in the uvula
Elevates and retracts uvula
Arches of the oral cavity
Palatopharyngeal arches lie posterior and medial to the palatoglossal arches with the palatine tonsil between them on the lateral oropharyngeal wall
3 regions of the nasal cavity
Respiratory region
Nasal vestibule
Olfactory region
