THRA.3

Question 1

Give the main constituent bones of the topic: “Bones of the Nasal Cavity”

Answer 1

1. Os palatinum
2. Os frontale
3. Os incisivum
4. Os nasale
5. Os pterygoideum
6. Os lacrimalis
7. Vomer
8. Os zygomaticum
9. Os ethmoidale
10. Maxilla

(FLIP ZEN MVP)

Question 2

​In the topic: Bones of the Nasal Cavity: Give the main constituent(s) of Os palatinum

Answer 2

1. Sinus palatinus
2. Margo liber

Question 3

Sinus palatinus

Answer 3

1. Small in lamina horizontalis in most species
2. Large in lamina perpendicularis in Eq

Question 4

Margo liber

Answer 4

Attachment of soft palate

Foramen palatinum majus:

• Rostral to margo liber in most species
• Caudomedially in Ru

Question 5

Which structure(s) pass through foramen palatinum majus?

Answer 5

• Canalis palatinus*:
• A./v./n. palatina major* (ex CN-V₂) (To the palatine plexus)

Question 6

Give the main constituent(s) of os incisivum

Answer 6

1. Foramen interincisiva (Ca)
2. Canalis interincisiva (Eq)
3. Fissura interincisiva (Ru/Su)

Question 7

Foramen/canalis/fissura interincisiva

Answer 7

Ca / Eq / Ru+Su respectively

Conducts a. palatina major

Ru: No Incisors, lamina dentalis present instead

Question 8

​In the topic: Bones of the Nasal Cavity: Give the main constituent(s) of os nasale

Answer 8

Incisura nasoincisiva

Question 9

​In the topic: Bones of the Nasal Cavity: Give the main component(s) of os pterygoideum

Answer 9

Hamulus pterygoideus

Question 10

Hamulus pterygoideus

Answer 10

Beyond the margin of the choanae

Well developed in Eq

Question 11

​In the topic: Bones of the Nasal Cavity: Give the main component(s) of os lacrimalis

Answer 11

1. Facies nasalis

Question 12

Facies nasalis

Answer 12

Forms the border of sinus frontalis and sinus maxillaris

Crossed by the ductus nasolacrimalis from the orbit

Question 13

Vomer

Answer 13

From meatus nasopharyngeus to crista nasalis

Two lateral plates form sulcus septalis, where septum nasi is found

Question 14

​In the topic: Bones of the Nasal Cavity: Give the main component(s) of os zygomaticum

Answer 14

Crista facialis (Eq, ØCa)

Question 15

Crista facialis

Answer 15

Eq, ØCa

From os zygomatica to maxilla

Barely visible in Ru, tuber faciale is instead seen

Question 16

​In the topic: Bones of the Nasal Cavity: Give the main component(s) of os ethmoidale

Answer 16

1. Labyrinthus ethmoidalis

Question 17

Labyrinthus ethmoidalis

Answer 17

From the caudal part of cavum nasi to lamina cribrosa

Highly vascularised and innervated structure

Ethmoturbinate warm, clean and humidify the incoming air

Olfaction

Question 18

Give the component(s) of labyrinthus ethmoidalis

Answer 18

1. Meatus nasi dorsalis (Olfaction)
2. Meatus nasi medius (Connects paranasal sinuses)
3. Meatus nasi ventralis (Runs to nasopharynx)
4. Meatus nasi communis (Connection between the meati)

Question 19

​In the topic: Bones of the Nasal Cavity: Give the main component(s) of maxilla

Answer 19

1. Foramen infraorbitalis
2. Rugae palatini

Question 20

Foramen infraorbitalis

Answer 20

Termination of canalis infraorbitalis

A./v./n. infraorbitalis (ex CN-V₂)

Question 21

Rugae palatini

Answer 21

Form oral mucosal surface of the palatum durum

Question 22

​In the topic: Bones of the Nasal Cavity: Give the key boney structures

Answer 22

1. Cavum nasi
2. Palatum durum
3. Diastema
4. Ethmoturbinalia

Question 23

Cavum nasi

Answer 23

Seperated by septum nasi on the vomer and caudally by the lamina perpendicularis

Ventral border: palatum durum

Lateral border: os incisivum, maxilla, os pterygoideum, os zygomaticum

Caudally bordered by lamina orbitalis of os ethmoidalis

Question 24

Palatum durum

Answer 24

Formed by:

• Lamina horizontalis of os palatinum
• Processus palatinus of os incisivum and maxilla

Seperates nasal and oral cavities

Supports the palatine plexus

Fissura palatina cross between maxilla and os incisivum

Question 25

Diastema

Answer 25

*'margo interalveolaris'* Between premolar region and the incisors Teeth are seperated by *septa interalveolaria* *Septa intraalveolaria* present within the alveoli

Question 26

*Ethmoturbinalia*

Answer 26

Each possess both a *lamina basalis* and a *lamina spiralis* and are split into two rows (3 in Eq) Ethmoturbinalia are subdivided into long and short ectoturbinalia Endoturbinate I forms the *concha nasalis dorsalis* Endoturbinate II forms *concha nasalis media* *Concha nasalis ventralis* are also called *maxiloturbinates*

Question 27

Give the numbers of Ethmoturbinalia accross the species

Answer 27

Ectoturbinalia: 6 in Ca; 18 in Ru; 20 in Su; 25 in Eq Endoturbinalia: 4 in Ca; 4 in Ru; 7 in Su; 6 in Eq