Biological complexity: fast healing oral mucosa (Introduction)

by David Turell , Thursday, April 21, 2022, 19:16 (947 days ago) @ David Turell

With teeth biting at hundreds of pounds per square inch and a wandering tongue pushing food around, no wonder oral mucosa is designed to heal fast:

https://www.realclearscience.com/blog/2022/04/21/your_mouth_has_super-healing_abilities...

"Your mouth has remarkable regenerative powers. A wound to your oral mucosa – the lining of the inside of your mouth – heals three to four times faster than an identical cut on your skin, with less likelihood of leaving a scar.

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"For starters, they noted that the structures of the external skin and oral mucosa are noticeably different. Chiefly, the oral mucosa is much thicker, with a slightly looser structure enabling it to bend more easily, and it has more blood vessels. Additional blood flow could certainly factor in to speedier healing.

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"Studies show that immune cells like neutrophils, macrophages, and T-cells build up quickly in oral mucosa then leave just a fast, while their arrival and departure are comparatively delayed in skin cells. The rapid and robust arrival of blood clotting cells called platelets in the mouth seems to trigger a large and speedy release of signaling proteins called chemokines, which trigger the waterfall of immune cells.

"In the ensuing healing phase, called proliferation, endothelial cells, fibroblasts, and epithelial cells – all of which either comprise or repair skin – migrate into the wound bed to regenerate the tissue. Here, the warm, moist, saliva-filled environment of the mouth seems to speed things along. Scabs do not form in the mouth, unlike on the skin, and so protein-rich saliva and even friendly oral microbes appear to aid in the healing process.

"Finally, in the remodeling phase of healing, immune cells send out small proteins called cytokines that reduce inflammation around the wound. Again, this process of reducing inflation occurs faster in the mouth compared to the skin. Then, over days, weeks, or months, fibroblasts and myofibroblasts get to work remodeling the structure that supports surrounding cells, called the extracellular matrix. Studies suggest that when this occurs in the presence of inflammation, scars are more likely to form (which explains why picking scabs, thus inflaming the tissue, leads to increased scarring).

"'It can be concluded that faster wound closure, the presence of saliva, a more rapid immune response, and increased extracellular matrix remodeling all contribute to the superior wound healing and reduced scar formation in oral mucosa, compared to skin," the authors summarized."

Comment: A very logical design. I might add a bitten tongue heals as quickly. but a deeply bitten tongue will require stitches.