13 - histogenesis, morphology, physiology or oral mucosa. Anatomy - main characteristics and morphology of oral mucosa. Types of oral mucosa. Cell composition, blood supply and innervation. Oral mucosa of lips and tongue. Characteristics of oral mucosa according to age

Histogenesis, morphology and physiology of oral mucosa

• from ectoderm and mesoderm

• oral epithelium forms the surface of oral mucosa that forms a barrier between the oral environment and the deeper tissues, its derived from the embryonic ectoderm

• It is stratified squamous epithelium and can be keratinised or non-keratinised, beneath the epithelium lies the connective tissue

what are the divisions of the stratified squamous epithelium?

1. lining mucosa - covers floor of mouth, cheeks, lips and soft palate

2. Masticatory mucosa - covers hard palate and alveolar ridges

3. Specialised mucosa - covers surfaces of tongue

Morphology of oral mucosa

• oral mucosa covers entire oral cavity

• starts from lips and adjacent skin - vermillion

• Covers - lined vestibule, alveolar bone, hard/soft palate, tongue and floor of oral cavity

• Oral mucosa is made up of thick stratified squamous epithelium (for wear and tear) supported by a lamina propria, which is composed of a papillary layer and a reticular layer

• Under oral mucosa is a tough collagenous submucosal layer with accessory salivary glands, except in areas where the submucosa is thin

what is under oral mucosa?

• a tough collagenous submucosal layer with accessory salivary glands, except in areas where the submucosa is thin

what is the oral mucosa made of?

• Oral mucosa is made up of thick stratified squamous epithelium (for wear and tear) supported by a lamina propria, which is composed of a papillary layer and a reticular layer

what is the cell composition of oral mucosa?

• non keratinised epithelium - in mobile areas like soft palate, ventral tongue, mouth floor, cheek and lip mucosal surfaces

• Keratinised epithelium - gums, hard palate, dorsal tongue surfaces

Blood supply or oral mucosa

• Facial vein, lingual vein and pterygoid venous plexus

Innervation of oral mucosa

• sensory innervation - trigeminal nerve maxillary and mandibular branches

• Taste - facial nerve, glossopharyngeal nerve and vagus nerve

• Motor - facial nerve = lips, hypoglossal = tongue

describe the oral mucosa of lips

• inner oral surface of lips is lined with moist surface, stratified squamous cells and non-keratinised epithelium

• Associated with small round seromucous glands of lamina propria

• Beneath lamina propria is submucosa with fibres of orbicularis oris muscle

describe the oral mucosa of tongue

• specialised mucosa - tongue surface, epithelial keratinised and non-keratinised papillae

• Masticatory mucosa - dorsal surface of tongue - keratinised stratified squamous epithelium

• Lining mucosa - ventral tongue, non-keratinised stratified squamous epithelium

Characteristic of oral mucosa in children

• thinner epithelium making it appear more bright

• less keratinised

• more fragile

• better regenerative capabilities