The tongue and teeth

The tongue

The Organ of Deglutition (Swallowing), Drinking, Taste – Gustatory papillae, Taste

buds, Chemoreceptors

cow tongue extras

Prehension; Manipulation of food during mastication

Dog tongue extras

Thermoregulation (Panting in dogs)

Cat tongue extras

Papillae serve as a “rasp”, helping to scrape small amounts of meat off the bones and move it towards the back of the mouth

Root of the tongue

Caudal fixed part

also attached to the hyoid apparatus

Body of the tongue

Middle part: Frenulum Linguae(Lingual Frenulum) - Ventral median fold

Apex of the tongue

Rostral free part

Highly muscular nature - vigorous movements.

Median Sulcus, Sublingual Caruncles

Filiform papillae

The most numerous

Cat - Modified and highly keratinized filiform papillae on the rostral 2/3 – dorsal aspect

Conical papillae

The caudal most, oropharyngeal region of the tongue - Dog

Gustatory papillae

These papillae have taste buds associated.

➢ Fungiform papillae

➢ Vallate papillae(Circumvallate)

➢ Foliate papillae

Mucosa of the tongue

Other papillae

Marginal papillae (Mechanical) – only in young –in suckling

Lenticular Papillae (Mechanical) – Only in Ruminants

The genioglossus muscle

Depress & Protrude the tongue – Take the tongue out

The hyoglossus muscle

Retract the tongue – Pull the tongue back

The Geniohyoideus muscle

Protrude the tongue – Take the tongue out

Not a tongue muscle but action is related to movement of the tongue

Anatomy of the extrinsic muscles of the tongue

Extrinsic Muscles of the tongue

The genioglossus muscle

The styloglossus muscle

The hyoglossus muscle

The geniohyoideus muscle

Muscles of the tongue: lateral aspect

Intrinsic Muscles of the Tongue(proper lingual muscles)

The superficial longitudinal fibers

The deep longitudinal fibers

The transverse and the perpendicular fiber

Blood Supply to the tongue - Arteries

Blood Supply to the tongue - Veins

Summary of innervation to the tongue

Tongue of the ruminant

The Major prehensile organ in the bovine

The lenticular papillae – Numerous Mechanical papillae on the Torus lingua

Conical papillae – larger than filiform, mainly on torus lingua

Foliate papillae are absent

Ruminant tongue pics

Tongue of the horse

Spatulated – the apex is not pointed; Not a prehensile organ

Distinct Torus lingua and fossa linguae are absent

Usual papillae present on the tongue including foliate papillae

Dorsal lingual cartilage – Hyaline cartilage accompanied by adipose tissue and muscles

Anatomy of the tongue of the horse

Microanatomy of the tongue

Stratified squamous epithelium

Dorsal – Papillae, Ventral - No papillae

Laminal propria submucosa: Lingual salivary glands(Minor)

Lyssa in the dog – fat filled, surrounded dense irregular connective tissue (fibrous rod)

Fungiform and Filiform Papillae, Tongue, Goat.

4. Filiform papilla

5. Fungiform papilla

7. Skeletal muscle

Circumvallate Papilla, Tongue, Goat

1. Core of Connective yissue,

4. Lingual salivary gland

2. papilla of Connective tissue,

5.Stratified squamous epithelium

3. Duct

6. Taste buds

Function of the teeth

Cutting and Tearing (Carnivores)

Grinding and Chewing(Herbivores)

Grasping and Holding (Omnivores and Predators)

Gnawing (Rodents and Some Mammals)

Defense and Fighting

Crown

The visible part of the tooth above the gumline

Shape varies depending on tooth function (e.g., sharp incisors vs. broad molars)

Root

The part of the tooth embedded in the alveolus/socket

Number of roots varies (single, double, multiple)

Neck

The junction between the crown and the root, at the gumline.

Furcation:

The area where the roots diverge in multi-rooted teeth.

Clinical significance: common site for periodontal disease

Enamel

The hardest substance in the body; protects the tooth.

Composition: 96% mineral, mostly hydroxyapatite.

Thickness varies among species and tooth type

Dentin:

Forms the bulk of the tooth; provides support for enamel.

Composition: 70% mineral, 30% organic material and water.

Continues to form throughout life

Pulp

Contains blood vessels, nerves, and connective tissue.

Provides nutrients to the tooth and allows for sensation.

Cementum

Covers the root; attaches the tooth to the periodontal ligament.

Composition: 50% mineral, similar to bone, Important for tooth anchorage

Anatomy of a tooth

Periodontium

Includes the gum/gingiva, alveolar bone(the socket), cementum on the root, the and the periodontal ligament/ membrane → connects the two across the periodontal space

Incisor teeth

typically single-rooted with a sharp incisal edge.

Canine teeth

Large, conical teeth used for piercing and holding prey. Single-rooted with a long root for strong anchorage.

Sexual dimorphism

Premolar teeth

for grinding and shearing food, variable number of roots

Molar teeth

Large, flat teeth used for grinding food, multiple roots

Ruminants teeth

no upper incisors. Instead, the hard palate is modified as a dental pad.

The canine teeth are modified and resemble the incisors, therefore, The canine tooth of domestic ruminants has commonly been counted as a fourth incisor

Dog dental formulation

Cat dental formulation

Pig dental formulation

Ruminant dental formulation