Why do some cuts leave scars, while others do not?

Last year I got a moderately-deep cut on my finger, and it left a scar. Six months later, the scar is still there. On the other hand, I've had lots of other cuts on my fingers, though none have left scars. Why is this? Is scarring related to the severity of the cut, or something else?

This depends on a number of factors. Here are the first two that come to mind:

1) Is the cut deep enough to reach the dermis (this is the layer below the epidermis) where scar tissue will form?

2) What is your general state of health, and was there an infection at the site of the cut, which would have altered the normal healing process.

Basically, not all cuts are created equal, especially if some are deeper than others and become infected.

Here's Why Paper Cuts Hurt So Damn Much, According to Science

You wouldn't think that a flimsy piece of paper could inflict such sharp pain on the human body, but of all life's little annoyances, paper cuts are one of the worst.

While not overly serious in the grand scheme of things, they sure provide a lot of pain for such a minor injury. So why do paper cuts hurt so much, even if they don't pierce the skin?

Turns out, it's your nerve endings that are mainly to blame: we've got more pain receptors in the tips of our fingers than almost anywhere else in the body, which you might have already realised if you've ever tried to pick up something very hot.

"Fingertips are how we explore the world, how we do small delicate tasks," dermatologist Hayley Goldbach from the University of California, Los Angeles, told Jason G. Goldman at the BBC. "So it makes sense that we have a lot of nerve endings there. It's kind of a safety mechanism."

These nerve endings are called nociceptors, and they warn the brain – through the sensation of pain – about high temperatures, dangerous chemicals, and pressure that could break the skin.

Some blame also lies with the paper, though – paper edges are not as smooth as they might appear from a distance, and can leave a rough trail of destruction on the skin, rather than a good, clean nick.

Finally, paper cuts are usually not deep enough to activate the body's natural defence mechanisms – such as blood clotting and scabbing – so the damaged nerve endings in our fingers are left exposed.

Not only that, but the open wound is flexed and strained every time we use our hands until the skin is repaired.

All of which means that paper cuts are disproportionately painful – or at least, that's what we can assume based on the limited evidence we've got . In the absence of a queue of volunteers lining up to slice open their fingers with paper, scientists have to use what they already know about the body to take an educated guess.

"We can use our knowledge of human anatomy to help us out here," said Goldbach. "It's all a question of anatomy."

But you can do a little scientific experimentation on yourself to personally examine the hypothesis. Get hold of a paperclip, then bend it so the two ends are close together and pointing in the same direction.

Try poking your back or legs and see if you can distinguish between the two sharp points, then try again on your hands or your face. It's much easier to feel both points the second time around because of the extra nerve endings.

Congratulations – you just discovered two-point discrimination, which is the ability to recognise two distinct impressions on the skin, and not confuse them as one.

In Scientific American's Instant Egghead video below, researchers suggest that there could be a psychological element to paper cuts as well: in our minds, the pain is made all the more acute because it was caused by something so small and apparently harmless.

So now you know the science behind paper cuts. But the most important tip? Exercise extreme caution around stationery.

A version of this article was first published in September 2016.

Proper wound care: How to minimize a scar

Whenever your skin is injured – whether by accident or from surgery – your body works to repair the wound. As your skin heals, a scar may form, as this is a natural part of the healing process.

Here are dermatologists’ tips for reducing the appearance of scars caused by injuries such as skinned knees or deep scratches.

Whenever your skin is injured—whether by accident or from surgery—your body works to repair the wound. As your skin heals, a scar may form, as this is a natural part of the healing process.

The appearance of a scar often depends on how well the wound heals. While scars from surgery or over joints like the knees and elbows are hard to avoid, scars caused by minor cuts and scrapes can become less noticeable by properly treating the wound at home.

Here are dermatologists’ tips for reducing the appearance of scars caused by injuries such as skinned knees or deep scratches:

Always keep your cut, scrape or other skin injury clean. Gently wash the area with mild soap and water to keep out germs and remove debris.

To help the injured skin heal, use petroleum jelly to keep the wound moist. Petroleum jelly prevents the wound from drying out and forming a scab wounds with scabs take longer to heal. This will also help prevent a scar from getting too large, deep or itchy. As long as the wound is cleaned daily, it is not necessary to use anti-bacterial ointments.

After cleaning the wound and applying petroleum jelly or a similar ointment, cover the skin with an adhesive bandage. For large scrapes, sores, burns or persistent redness, it may be helpful to use hydrogel or silicone gel sheets.

Change your bandage daily to keep the wound clean while it heals. If you have skin that is sensitive to adhesives, try a non-adhesive gauze pad with paper tape. If using silicone gel or hydrogel sheets, follow the instructions on the package for changing the sheets.

If your injury requires stitches, follow your doctor’s advice on how to care for the wound and when to get the stitches removed. This may help minimize the appearance of a scar.

Apply sunscreen to the wound after it has healed. Sun protection may help reduce red or brown discoloration and help the scar fade faster. Always use a broad-spectrum sunscreen with an SPF of 30 or higher and reapply frequently.

If you have minor cuts or scrapes, you can help reduce the appearance of a scar by properly treating the injury at home. However, if your injury is deep, very painful or if your skin becomes infected, seek immediate medical care.

A burn can turn into a serious injury without proper treatment.

Although no scar can be completely eliminated, most scars fade over time. If you’re worried about the appearance of a scar, see a board-certified dermatologist. A dermatologist can answer your questions and talk about ways to make your scar less visible.

Why do some wounds take so long to heal?

There are many variables to consider when analyzing slow healing wounds such as age, status of health, lifestyle, nutrition or post-surgery. Non-closing wounds are known as ulcers, and when located at the lower leg, feet or ankles, even walking can extend the healing process due to frequent pressure.

Poor blood flow to the wound can also prevent sores from healing quickly and could be a signal of diabetes or another chronic disease. If a patient is a smoker this also slows down the healing process, since smoking keeps damaged cells in an inflammatory state, while being deprived of much needed oxygen.

Steps of the healing process

Natural wound healing involves several steps. Right after an injury, the body increases blood flow to the trauma area. This is when a wound becomes red and warm, while allowing white blood cells and platelets to get to the spot. Platelets activate blood clotting or coagulation and prevent further bleeding. At the same time, phagocytes, called scavenger cells remove damaged or dead cells.

Oxygen and other nutrients produce new skin, including new blood vessels. Connective tissue fibers or collagen are developed, and then small muscle cells are produced. At this stage the edges begin joining together so the wound can close.

Speeding up the healing of wounds

Barriers to wound healing include diet and poor nutrition. According to Wound Care Centers and Health, protein is the most important part of your diet when trying to promote wound healing. Energy, or calories from carbohydrates and fats, amino acids, antioxidants and minerals – especially zinc are also important.

Protein helps repair the damaged tissue from your wound and adding more protein than usual to the diet has been proven to help the healing process. This means two to three servings of protein a day with each meal containing at least two to three ounces of meat. One cup of beans or two tablespoons of peanut butter are alternatives (but not too much peanut butter if weight is a problem because of the fat). On the other hand, when not enough daily calories are consumed, the body may convert more of the protein ingested to energy instead of healing.

In addition to lifestyle changes, The Woundcare Clinic of Savannah offers advanced therapies to help speed the healing process.

We recommend you consult your physician for specific nutritional recommendations based on your condition(s). If you live in the Savannah or Hilton Head area and have any questions about your wound care management, please contact us.

Reasons For Your Weeping Wound

There are several reasons that can be the cause behind your weeping wound. Here we are talking of weeping wound that happen after your wound is being well – cleaned and well – dressed with the right ointment and being covered with gauze or bandage.

Infection – The first possible reason of your wound that is weeping is that it is infected with fungus or other bacteria that is roaming around in the air. If your wound is being infected, not only it can discharge yellow or greenish fluid but the discharge can also create a foul odor.

In this case of weeping wound the discomfort can be followed by pain, irritation and swelling on your wound as well as on the surrounding area of your wound. Your general health can also be affected when your wound is infected, you can experience fever or malaise following an infected wound.

Extreme moist – While it is true that it is good to keep your wound covered or closed to prevent it from infection, but if you leave in a very humid area and you naturally tend to sweat more, your wound can also create discharge that can make your wound weep in a longer period of time.

Some people also can have a naturally more oily skin type so their skin might have higher moisture level compared to other people who have dry skin type. In this case, there is higher possibility for a wound to weep and it might be better to let the wound to dry out in order for it to heal.

Healing – There is another reason why your wound is weeping and it is positive. Your wound might also weep or discharging fluid when it is going to heal. As we touched in the opening of this article, a wound might also discharge some clear fluid when it is healing.

Your body might produce this clear fluid in order to flush out all the small dirt that is present on your wound. This fluid also transports bacteria away. The other good thing that this fluid does is transporting the nutrition into your wound. It also provides your wound and the surrounding skin cell the needed nutrition so it can heal properly.


Can I prevent scars?

Although you can’t always prevent injuries that cause scars, you can reduce the risk of a scar forming after an injury. If a scar does develop, careful care can make the scar less noticeable.

To reduce the risk of scarring, you should:

  • See your healthcare provider: If you have a wound that may leave a scar, visit your provider for an examination. You may need stitches or special bandages to hold the skin together while it heals. Stitches can minimize scarring. Be sure to follow your provider’s instructions when caring for stitches. Depending on the type and location of the wound you may need oral or topical antibiotics to prevent infection.
  • Clean the wound: Wash the area with soap and water. Clean out any dirt or dried blood, and apply a bandage over the wound to keep germs out. Be sure to change the bandage often as the wound heals.
  • Keep the wound moist: Applying petroleum jelly or moist burn pads will keep the wound from becoming too dry and developing a scab. Scabs can make scarring worse.
  • Protect it from the sun: Cover the scar or use sunscreen to protect it. Sun exposure can make a scar darker. Repeated exposure increases the risk of developing skin cancer.
  • Keep up your nutrition: Having low levels of vitamin D or C in your system can make scarring worse and you need adequate high quality protein in your diet to help your skin make what is needed to heal.

Physical Examination

Your doctor will get your medical history and do a physical examination.

While physical adhesions will not help in finding adhesions, it will indicate a blockage in the cervix if the instrument is unable to enter the cervix.

Hormone Test

The doctor could also order hormone tests, which will help in ruling out endocrine problems, or might use hormones to induce bleeding.

Saline Infusion Sonography (SIS)

Another option with your doctor is saline infusion sonography. Also known as sonohysterography or uterine ultrasound, SIS involves using a saline solution that flows into the uterus, helping in getting a clear image of the uterus.


Also known as uterosalpingography, HSG combines radioactive material and X-ray. The radioactive material is placed in the fallopian tubes and the uterus to indicate any blockages or growths.


Hysteroscopy is the best bet when it comes to diagnosing scars in the uterus. Hysteroscopy involves your doctor placing a telescope and camera in the uterus to view the entire uterine cavity.

The extreme pain felt when something injures your fingers is simply the result of evolution working as it should

This actually makes a good deal of evolutionary sense. “Fingertips are how we explore the world, how we do small delicate tasks,” explains Goldbach. “So it makes sense that we have a lot of nerve endings there. It’s kind of a safety mechanism.”

It’s reasonable that your brain would devote more neural real estate to continuously monitoring possible threats to your hands, since they’re the main vehicles the body has for interacting with the world. If you come into contact with something extremely hot, for example, or sharp, it’s just more likely that you would interact with it using your hands. So the extreme pain felt when something injures your fingers is simply the result of evolution working as it should, providing a little extra encouragement for you to keep those hands safe.

And then there’s the weapon itself. Do a quick Google search and you might become convinced that due to its porous nature, paper is home to a bacterial menagerie, just waiting to colonise your paper-inflicted wounds. But whether or not that’s true, the presence of bacteria and other microscopic beasties can’t explain the sensation of pain, at least not at the moment of cutting. Bacteria can lead to infections if wounds are left untreated, which themselves can be painful, but that takes a bit of time.

Paper edges may look straight, but they are in fact serrated, cutting through skin like a saw (Credit: iStock)

But there is something to the idea that paper is a uniquely painful weapon.

To the naked eye, it might seem as if a paper's edge is fairly straight and smooth. But if you were to zoom in, you’d find that paper is more akin to a saw than to a blade. So when a paper cuts open your skin, it leaves behind a chaotic path of destruction rather than a smooth laceration. It rips, tears, and shreds your skin, rather than making clean slice, as a razor or knife blade would do.

And if that wasn’t enough, paper cuts are typically shallow – but not too shallow. “They’re deep enough to get past the top layer of the skin, otherwise they wouldn’t hurt. The top layer of skin has no nerve endings,” says Goldbach.

Facial Wounds: Improving Healing Times for Cuts and Scars

You can cover up injuries on nearly every part of your body, but a wound on your face is more difficult to hide. Knowing how to treat cuts or scars properly is essential to reducing facial wound healing time and improving the chances of healing facial scars completely.

Initial Treatment Steps

When a facial wound occurs, the first step is to stop the bleeding. Using a clean cloth or medical gauze, apply pressure to the cut until bleeding has completely stopped. Keeping your head elevated above your heart will help stop bleeding and reduce swelling. Remaining calm and resisting the urge to cry is helpful because crying increases blood flow to the face, which can cause facial injuries to bleed more.

Cleaning a Facial Wound

Once the bleeding has stopped, cleaning the wound thoroughly will help to decrease your facial wound healing time. Wash your hands with soap and hot water, then dry with a clean towel to reduce the chances of infecting your wound. Gently clean the wound with soap and cool water. Warm water on an open wound will cause it to start bleeding again. Remove any dirt or debris with water and gentle patting with a clean cloth. If you must use tweezers to remove debris, sterilize them with rubbing alcohol. Do not use hydrogen peroxide because it can damage skin tissues.

Bandaging a Facial Wound

When the cut is clean, apply an antibiotic ointment directly to the wound. Providing the optimal level of moisture to the injury will improve your facial wound healing time. Place a sterile wound dressing over the wound and make sure it stays in place. Try not to move your facial muscles too much to keep the wound site from moving around as it begins the healing process. To prevent and reduce swelling, place an ice pack onto the wound for 10 to 20 minutes, three to four times a day.

Seeking Professional Treatment

When a facial cut is deep, pulled apart, or the result of an impact to the head, you need to seek medical treatment as soon as possible. If the cut is wide enough where you cannot pull the edges back together, the wound will require stitches to heal properly and reduce scarring. Watch for signs of infection, such as redness, swelling, pus, fever, or heat coming from the wound. Infection can occur at any point during the wound healing process, so it is important to keep the wound clean and covered with a fresh new dressing daily.

Additional Wound Treatment

For the first 24 hours after a facial wound has occurred, do not take aspirin or NSAIDS because they can inhibit blood clotting and may increase blood flow to the facial area. During the first 48 hours after injury, avoid hot showers, heating pads, hot foods, and hot fluids, as these can increase swelling. Once the wound has closed, you can remove the bandage, but avoid sunlight exposure by applying sunscreen. Do not scratch an itchy wound or pick at any scabs, as this will only result in permanent scarring.

Healing Facial Scars

If you do end up with a facial scar, you can still treat it with silicone gel sheets. Wearing these sheets may help the wound fade and should be worn for at least three months after the wound has healed. If a scar is significant, a dermatologist or plastic surgeon may be consulted to determine if fillers, steroids, microdermabrasion, laser resurfacing, or surgery can be used to further treat any healing facial scars.

Advanced Tissue is the nation’s leader in delivering specialized wound care supplies to patients, delivering to both homes and long-term care facilities.

Please note: blog posts are rarely updated after the original post. Because the medical industry is ever changing please make certain to reference the current product list as well as up-to-date industry information when considering product selection or treatment. Always consult a physician to discuss specific concerns or questions related to your health.

What About Aloe Vera?

Aloe vera is known for soothing many types of skin problems, such as psoriasis or sunburns. Early tests in lab rats show it may reduce the appearance of scars. But there’s been little research on this in humans, although people have traditionally used aloe vera on skin for centuries. It’s probably safe to try. Sometimes scar tissue can feel tight aloe vera may keep the skin more supple to help ease that feeling.

Annals of Plastic Surgery: “Topical Application of Aloe vera Accelerated Wound Healing, Modeling, and Remodeling: An Experimental Study.”

Cleveland Clinic: “Scars,” “3 Ways To Get Rid of Your Acne Scars.”

Mayo Clinic: “Mayo Clinic Q and A: Treatment Options for Acne Scars That Don’t Improve Over Time,” “Natural Acne Treatment: What's Most Effective?”

Ginekologia Polska: “Comparison of the effectiveness of topical silicone gel and corticosteroid cream on the pfannenstiel scar prevention -- a randomized controlled trial.”

Journal of Cutaneous and Aesthetic Surgery: “The efficacy of silicone gel for the treatment of hypertrophic scars and keloids.”

International Journal of Molecular Sciences: “Anti-Inflammatory and Skin Barrier Repair Effects of Topical Application of Some Plant Oils.”

Skin Pharmacology and Physiology: “Effect of topical application of virgin coconut oil on skin components and antioxidant status during dermal wound healing in young rats.”

Nutrients: “Zinc in wound healing modulation.”

American Society for Dermatologic Surgery: “Scars.”

Canadian Journal of Surgery: “Lymphatic cording or axillary web syndrome after breast cancer surgery.”

British Medical Journal: “Skin Scarring.”

Indian Journal of Dermatology: “Efficacy of punch elevation combined with fractional carbon dioxide laser resurfacing in facial atrophic acne scarring: A randomized split-face clinical study.”

Journal of Cutaneous and Aesthetic Surgery: “Acne Scar Subcision.”

Archives of Dermatological Research: “A comprehensive evidence-based review on the role of topicals and dressings in the management of skin scarring.”

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