Ch. 27 - Nose, Nasal Cavity, and Paranasal Sinuses

The nasolacrimal duct is located within the:

Inferior meatus

The external nose has bony attachments to the:

Nasal bones and lacrimal bones

What is the function of respiratory epithelium?

Respiratory epithelium functions to trap contaminants entering the nasal cavity and move them out of the nasal cavity.

What bones would we find in the lateral wall of the nasal cavity?

The lateral wall is formed on the upper portion from the ethmoid bone and the lower portion from the maxilla. Close to the point of union of those two bones is the inferior nasal concha.

Which bones or structures form the nasal septum?

The lower part of the nasal septum is formed from the vomer bone, whereas the upper portion is formed from the perpendicular plate of the ethmoid bone. The anterior end of the nasal septum is formed from the nasal septal cartilage.

What opens into the inferior meatus?

The nasolacrimal duct

The _____ and ethmoid form the main part of the nasal septum.

Vomer

What opens into the sphenoethmoidal recess?

sphenoid sinuses

Nasal Conchae

- 3 shelves in the lateral wall of the nasal cavity - Project in toward the septum - helps to have as much surface area as possible in the nasal cavity. - also helps filter incoming air

Nose

- Portion of the nasal complex that protrudes outward from the skeletal component. - Attached superiorly to the nasal bones and inferiorly to the anterior nasal spine.

Maxillary Sinuses

- the largest of the paranasal sinuses - open into the posterior end of the hiatus semilunaris through one or more openings - grows over time - everybody's maxillary sinus is different - during a nasal infection, swelling occurs in the nasal mucosa - if the sinus has a very small opening(s) it may swell shut as a result of the mucosal edema. - as the infection increases, the pressure increases - the use of nasal sprays gives temporary relief, but then the cavity clogs again.

What is a meatus?

A meatus is the space underneath the projections of the nasal conchae.

Why may a maxillary sinus infection seem to be coming from the teeth?

A sinus infection may seem to come from teeth because the same nerve that supplies a tooth also supplies a part of the mucosa of the maxillary sinus. Daily messages go to the brain from the teeth, and then during a sinus infection a message is sent from an infected mucosa of the sinus. The brain is so used to getting messages from the tooth that it interprets the sinus pain as being tooth-originated pain.

Which bone(s) is found in the lateral wall of the nasal cavity?

Ethmoid bone, maxilla, and inferior nasal cochae

What are the functions of the sinuses?

- OLD: warm the air as it passes into the respiratory system - NEW: lighten the overall bone weight

Ala

- Protruding lateral margin - Known individually as a wing of the nose

Nasal Aperture

- The anterior most portion of the nasal cavity - Somewhat pear shaped

Paranasal Sinuses

- There are 4 pairs: two ethmoids, two frontals, two maxillaries, and two sphenoids. - They are not easily seen at first - have to find the nasal conchae first.

Hiatus Semilunaris

- a half-moon shaped opening that lies beneath the middle nasal concha.

Superior Nasal Conchae

- a shelflike structure that makes up the lateral walls of the nasal cavity - more superior

Middle Nasal Conchae

- a shelflike structure that makes up the lateral walls of the nasal cavity - toward the middle

Inferior Nasal Conchae

- a shelflike structure that makes up the lower part of the lateral walls of the nasal cavity

Choana

- also known as the "posterior nasal aperture" - posterior part of the nasal septum

Prosthetic Appliance

- any constructed appliance that replaces a missing part

Meatus

- area of the lateral nasal wall sheltered underneath each concha

Periapical

- around the tip of the tooth root

Inferior Meatus

- beneath the inferior nasal concha and has one small opening, which is the opening of the nasolacrimal duct.

Ethmoid Bulla

- bulbous ridge above the hiatus semilunar

Nasolacrimal duct

- carries tears from the corner of the eye into the nasal cavity.

Dilacerated

- curved tooth roots because of disturbances in development

Olfactory Epithelium

- epithelium in the roof of the nasal cavity and comes down onto the upper surface of the superior concha and upper nasal septum. - modified and has nerve fibers that perceive odors.

Inferior Portion/Floor of Nasal Cavity

- formed from the bones of the hard palate, which are the palatal processes of the maxillae and the horizontal portion of the palatine bones.

Septum

- formed from the vomer bone and a portion of the ethmoid bone as well as the fibrocartilaginous part of the septum.

Ethmoid Sinuses

- frequently called "ethmoid air cells" because they are not single-paired sinuses like the other paranasal sinuses but are subdivided into numerous small compartments. - further divided into anterior, middle, and posterior ethmoid air cells - infections are difficult to treat because of the small compartments. when infected, they give a feeling of congestion and aching within the nasal cavity area.

Middle Meatus

- lies beneath the middle nasal concha, where there is a crescent-shaped opening called the hiatus semilunaris.

Superior Meatus

- lies beneath the superior concha and is the smallest meatus

Middle Ethmoids

- located in the base of the middle nasal concha, just behind the anterior air cells - also located within the ethmoid bulla - may have a couple of openings, one on the ethmoid bull and another possibly in the hiatus semilunaris

Posterior Ethmoids

- located in the base of the superior nasal concha and open into the superior meatus

Anterior Ethmoids

- located in the lateral wall of the nasal cavity at the base of the middle nasal concha. - open into the hiatus semilunaris just posterior-inferior to the opening for the frontal sinus.

Sphenoid Sinuses

- paired - located in the body of the sphenoid bone just underneath the pituitary fossa (which is located in the middle cranial fossa) - cross the midline - open into the highest and most posterior part of the nasal cavity - the sphenoethmoidal recess - infections in these sinuses can cause pressure and a congested feeling that is hard to localize but is deep in the midline of the head.

Frontal Sinuses

- paired - located in the frontal bone just above the orbital cavity - vary in size from person to person - frequently cross the midline and may be partially located on the opposite side. - drain into the very anterior end of the hiatus semilunaris. - infections of these sinuses can cause pressure and pain just above the eye.

Sphenoethmoidal Recess

- portion of the body of the sphenoid bone where it meets the ethmoid bone

Respiratory Epithelium

- psudostratified columnar epithelium with goblet cells - primarily found in the respiratory tract. - has cilia that moves in a synchronized beating pattern toward the anterior portion of the nasal cavity. The cilia traps contaminants as they enter the nasal cavity and moves them toward the front where they are removed by blowing the nose

Superior Portion of Nasal Cavity

- small holes that open into the anterior cranial fossa through the cribriform plate of the ethmoid bone to transmit the olfactory nerves from the nose up to the brain.

Why, anatomically, may maxillary sinuses create problems with sinus infections and with maxillary posterior teeth extractions?

Maxillary sinuses may cause infections because the opening is high in the medial wall and may have small openings, both of which can cause drainage problems. The sinus may dip in between the bent roots of maxillary posterior teeth and make them difficult to extract.

Where specifically is the olfactory epithelium found?

Olfactory epithelium is found in the roof of the nasal cavity. It extends down over the superior surface of the superior nasal concha and about 10 mm down the nasal septum.

The sphenoethmoidal recess is found in the ______ portion of the nasal cavity.

Posterior-superior

What opens into the middle meatus?

in the hiatus semilunaris, from anterior to posterior, the openings for the frontal siuses, anterior ethmoid air cells, and maxillary sinus, onto the ethmoid bulla, the opening of the middle ethmoid air cells.

What opens into the superior meatus?

posterior ethmoid air cells