Enhancing Skin Growth Part 3: The Dartos Fascia
In this series, we have been comparing medical skin expansion to foreskin restoration. Although the process is very much the same, there is one major anatomical difference between the two. On most of the body, skin has three layers: the epidermis, dermis, and hypodermis or subcutaneous fat. The foreskin is different in that instead of the hypodermis, and underneath the epidermis and dermis (and underneath the inner mucosa) is a layer called the dartos fascia.
What is the Dartos Fascia?
The dartos fascia, also sometimes called the dartos muscle, is a layer of fascia in the foreskin. It is a “mosaic” of thin bundles of smooth muscle that are arranged in all different directions, with collagen fibers in between.(1,2) It is continuous with the fascia of the scrotum and perineum, as well as the fascia of the abdomen. It is also connected to the cremaster muscle, which in tandem allow the scrotum to shrink and relax in response to temperature, keeping sperm from getting too hot or too cold. This also allows the foreskin to shrink in order to conform to the glans while flaccid and relax to accommodate the penis when erect. Since the foreskin is not anchored to the body in the same way other skin is, the unique qualities of the dartos fascia give the foreskin structure and strength, as well as flexibility and mobility, which all together make possible for the gliding action of the foreskin.
Fascia and Restoration
Skeptics of foreskin restoration have claimed that since the dartos fascia is severed during circumcision, it can’t regrow in a restored foreskin and isn’t functional. Evidence from thousands of men who have restored show that this is clearly not the case. Restored foreskin does shrink and conform to the penis much like an intact foreskin, which shows that the dartos fascia does lengthen and is functional. There is also a misconception that a natural intact foreskin has some sort of sphincter muscle at the end that causes it to close at the end of the glans. Research so far has shown that the muscle fibers are randomly oriented throughout the dartos fascia, and that nowhere is there a band of muscle fibers that would act like a sphincter.(1) This explains why restored foreskin is able to taper at the end of the glans in the same way a natural foreskin does, and why it is cosmetically hard to distinguish from a natural foreskin.
The question then is, how does the dartos fascia grow? We do know that fascia in other parts of the body does regenerate in response to mechanical stress.(3) Smooth muscle has the ability to proliferate (i.e. create new cells) under mechanical stress as well.(4) Evidence from restorers as explained above suggests that there is actually growth of new smooth muscle. Likely what is happening during restoration is that tension is causing micro tears in the fascia. In response to the mechanical stress, smooth muscle cells are proliferating, and fibroblasts are repairing and adding collagen in between.
I want to emphasize the work micro in micro tear, meaning that this is happening at a microscopic level. You do not need to stress the fascia to the point of pain or discomfort to create micro tearing. Pain, burning, and discomfort are signs of macro tears, which are just causing injury and are going to slow down or halt the expansion process.
Medical skin expansion is very fast compared to foreskin restoration. In the example of breast reconstruction in part 1, we saw that expanders were able to be filled to around 400 cc of saline in a few months. This would be more than enough skin to restore a foreskin. The difference is that there is no expansion of fascia in breast reconstruction. This points to the expansion of the dartos fascia as what is causing foreskin restoration to take so long. It is most likely that it just takes a lot longer for the dartos fascia to expand than it does for the dermis and epidermis to expand. We could even boil down foreskin restoration to a matter of fascia expansion and not skin expansion. Although each expand under different processes, it appears that expansion of the dartos layer may be the primary focus. Skin is much easier to expand, and methods that work for expand the fascia are secondarily adequate for expanding skin.
This leaves us with the question, how do we optimize and speed up expansion of the dartos fascia? I think there are a few important factors to consider:
Tension: You need enough tension to mechanically stress the fascia and create micro tearing, but not too much to where the fascia cannot repair. I go into detail on the proper amount of tension in The Complete Guide to Foreskin Restoration.
Time Under Tension: In order for the dartos fascia to lengthen in the way we want, the skin needs to be mechanically stretched during the repair and regeneration process. This means that it is ideal for the skin to be under tension for as many hours a day as possible. Experience shows that 8-12 hours a day is sufficient. Using a retainer when not under tension is also a good idea in that it keeps the skin (and fascia) lengthened forward. For safety reasons, the skin should not be under tension while sleeping.
Collagen: Fascia is largely made out of collagen, so it is important to make sure that your body’s collagen synthesis is optimized. Details on how to do this were covered in part 2.
Growth Factors: We have a good idea of the optimal tension and time to create the proper stress response in the dartos fascia, but growth is then dependent on how quickly it can be repaired. Is there any way to speed up or enhancing the regeneration process of the fascia? This will be the question we try to answer in part 4.
References:
1. https://www.cirp.org/library/anatomy/lakshmanan/
2. https://www.cirp.org/library/anatomy/jefferson/
3. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6241620/
4. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8391896/
Image: "Greek Statue" by markplymouth is licensed under CC BY 2.0.