Desvendando a Histologia da Mucosa Oral

Summary

The video discusses the structure and function of the oral mucosa, covering its composition, types of epithelial cells, and key features. It explains the differences between keratinized and non-keratinized epithelium and the role of specific cells like melanocytes, Langerhans cells, and Merkel cells. The video also highlights the structure of the lamina propria and its cellular components, including fibroblasts and macrophages. Additionally, the video touches on different types of oral mucosa, such as lining, masticatory, and specialized mucosa, with emphasis on the papillae of the tongue and their functions.

Takeaways

• 🧠 Activate your brain for revision by setting up an appropriate study environment: a computer, coffee, silence, and avoiding distractions like being in bed.
• 👅 The oral mucosa lines the internal surface of the oral cavity and is composed of epithelium and lamina propria, visible in areas like the palate, tongue, and gums.
• 🧬 Oral epithelium is stratified squamous, containing keratinocytes, with its apical layers having a squamous appearance.
• 🔬 There are three main types of cells in the epithelium: keratinocytes, melanocytes, Langerhans cells, and Merkel cells.
• 🌟 Keratinized epithelium is divided into basal, spinous, granular, and corneal layers, while non-keratinized epithelium has basal, spinous, intermediate, and superficial layers.
• 💡 Keratinized cells lose their nuclei and organelles as they mature, whereas non-keratinized cells retain both.
• 🖤 Melanocytes produce melanin and are responsible for darker pigmentation in certain areas like the gums.
• 🔗 The lamina propria consists of loose connective tissue, with important cells like fibroblasts, macrophages, and mast cells.
• 🦷 Different types of oral mucosa include lining, masticatory, and specialized mucosa, each with distinct characteristics and functions.
• 👅 Specialized mucosa on the tongue includes different types of papillae, such as filiform, fungiform, foliate, and circumvallate, which may or may not contain taste buds.

Q & A

What is the primary function of the oral mucosa?

The primary function of the oral mucosa is to line the internal surfaces of the oral cavity, providing protection and facilitating interaction with external stimuli.

What are the two main components of the oral mucosa?

The two main components of the oral mucosa are the epithelium and the lamina propria.

How is the oral epithelium classified?

The oral epithelium is classified as stratified squamous, meaning it consists of multiple layers of epithelial cells, mainly keratinocytes, with the most superficial cells being flattened or squamous.

What are the types of cells found in the oral epithelium?

The types of cells in the oral epithelium include keratinocytes, non-keratinocytes, melanocytes, Langerhans cells, and Merkel cells.

What are the differences between keratinized and non-keratinized epithelium?

Keratinized epithelium has a cornified layer with dead, dehydrated cells without nuclei or organelles, while non-keratinized epithelium has nucleated cells with organelles in its superficial layers.

What is the function of melanocytes in the oral mucosa?

Melanocytes produce melanin, which gives pigmentation to areas like the gingiva, contributing to a brownish coloration in some regions.

What are Langerhans cells and their role in the oral epithelium?

Langerhans cells are antigen-presenting cells found in permeable epithelial tissues, playing a role in immune response.

What is the function of Merkel cells in the oral mucosa?

Merkel cells are sensory receptor cells that connect to unmyelinated nerve fibers, contributing to tactile sensation.

What are the main cellular components of the lamina propria?

The main cellular components of the lamina propria include fibroblasts, macrophages, and mast cells. Fibroblasts produce extracellular matrix, macrophages are involved in phagocytosis and immune response, and mast cells contain granules with histamine and heparin involved in inflammatory reactions.

What are the three types of oral mucosa and where are they located?

The three types of oral mucosa are lining mucosa (found in areas like the labial and buccal mucosa, alveolar mucosa, soft palate, and ventral surface of the tongue), masticatory mucosa (found in regions subjected to friction, such as the attached gingiva and hard palate), and specialized mucosa (found on the dorsum of the tongue and associated with taste buds).