Oral cavity

TONGUE

Made up of intrinsic and extrinsic muscles

Intrinsic muscles

Superior, Inferior, Transverse, vertical

Extrinsic muscles

Genioglossus, hyoglossus, styloglosus and platoglossus

Dorsum of the anterior 2/3 is roughened by the present of 3 types of papillae:

Filiform, Fungiform, Vallate

Inferior surface: lingual frenulum in the midline, highly vascularised

Clinical notes

Upper airway obstruction in unconscious person (also snoring)

Paralysis (hypoglossal nerve)

Pallor (evidence anemia)

Laceration (evidence epileptic attack)

Colour (cyanosis, smoking)

Primary (Baby) Teeth Eruption Order

There are 20 baby teeth in total. They almost always appear in this specific sequence:

  1. Central Incisors: The bottom two first (around 6–10 months), then the top two.

  2. Lateral Incisors: The top ones usually come in next, followed by the bottom ones (8–13 months).

  3. First Molars: Instead of the "vampire" teeth (canines) coming next, the first molars jump the line to provide a surface for chewing (13–19 months).

  4. Canines (Cuspids): These fill the gap between the incisors and the molars (16–23 months).

  5. Second Molars: The very back baby teeth (23–33 months).

Permanent (Adult) Teeth Eruption Order

There are 32 permanent teeth. The "6-year-old molars" are usually the first to arrive, often before any baby teeth have even fallen out!

  • First Molars (6–7 years): These erupt behind the baby teeth; they don't replace any.

  • Central Incisors (6–8 years): These replace the front baby teeth.

  • Lateral Incisors (7–9 years): These replace the side front teeth.

  • First Premolars (Bicuspids) (10–11 years): These replace the baby first molars.

  • Canines (10–12 years): Often called "eye teeth."

  • Second Premolars (10–12 years): These replace the baby second molars.

  • Second Molars (12–13 years): The "12-year-old molars."

  • Third Molars (17–21 years): Wisdom teeth.

Parotid gland

The parotid (Stensen’s) duct crosses the masseter and pierces the buccinator muscle and open into the mouth opposite 2nd upper molar

Submandibular gland:

Submandibular gland lies inferior to the body of the mandible and covered partially by mylohyoid muscle

The submandibular (wharton’s) duct empty into the floor of the mouth on both side of lingual frenulum

Sublingual gland:

Sublingual gland lingual lies under the mucosa of the floor of the mouth. Possesses several small ducts that open into floor of the mouth