Gum recession happens when the edge of your gum tissue moves down (or up, on upper teeth) and exposes parts of the tooth root that are normally hidden. It’s a gradual process, often taking years, and it results from a combination of inflammation, physical wear, and the slow breakdown of the connective tissue that holds your gums firmly against your teeth. About 60% of adults 65 and older have some form of periodontal disease, but recession can start much earlier depending on the cause.
What Holds Your Gums in Place
Your gums are anchored to your teeth and jawbone by a dense network of collagen fibers. These fibers form a tight seal around each tooth, protecting the root and the bone underneath. Your body constantly breaks down and rebuilds this collagen as part of normal tissue maintenance. In a healthy mouth, the rate of breakdown and repair stays balanced, so the gum line holds steady.
When something disrupts that balance, either by speeding up destruction or slowing down repair, the attachment weakens and the gum gradually pulls away from the tooth. That’s recession in its simplest form. It can happen on the outer surface of a tooth, between teeth, or both, and it progresses at different rates depending on what’s driving it.
How Bacteria Break Down Gum Tissue
The most common driver of recession is chronic gum inflammation caused by bacterial plaque. When plaque builds up along the gum line, harmful bacteria trigger an immune response. Your body sends inflammatory cells to fight the infection, but those same immune signals also activate a family of enzymes called matrix metalloproteinases (MMPs). These enzymes chew through the collagen fibers that anchor your gums to the tooth.
The process works in stages. First, one type of enzyme strips away the protective coating around collagen fibers, leaving them exposed. Then collagen-cutting enzymes move in and slice through the fibers themselves. Meanwhile, certain periodontal bacteria produce their own tissue-destroying enzymes, accelerating the damage beyond what your immune response alone would cause.
This is the same process behind periodontitis, the advanced form of gum disease. It starts as gingivitis, where gums are swollen and bleed easily but haven’t yet lost their attachment to the tooth. If the inflammation persists, the attachment fibers break down, the gum separates from the tooth surface, and the pocket between gum and tooth deepens. As the pocket grows, the gum margin migrates further down the root. Clinicians track this by measuring the distance from a fixed point on the tooth to the bottom of that pocket, a measurement called clinical attachment level. It’s the most reliable way to gauge how much support a tooth has lost over time.
Physical Damage From Brushing
You don’t need an infection to develop recession. Mechanical wear from aggressive toothbrushing is one of the most common non-disease causes, and it tends to show up on the outer surfaces of teeth, especially canines and premolars.
Horizontal scrubbing with a hard-bristled brush and excessive force wears away the thin gum tissue at the tooth’s neck. High-abrasive toothpastes compound the problem. Over months and years, the gum margin thins, tears, and retreats. The tooth surface just above the root (the cervical area) also loses its protective enamel layer through this abrasion, which is why recession from brushing often comes with a notched or scooped-out area at the gum line.
Gentler techniques make a real difference. Angled, short vibratory strokes directed at the gum line (sometimes called the modified Bass technique) clean effectively without traumatizing the tissue. Soft-bristled brushes flex instead of cutting, and low-abrasive toothpastes reduce surface wear. If you already have recession on specific teeth, switching your technique can stop it from progressing further.
Grinding, Clenching, and Micro-Trauma
Bruxism, the habit of grinding or clenching your teeth, generates forces that can exceed ten times the pressure of normal chewing. That force doesn’t just stress the teeth. It strains the periodontal ligament (the thin tissue that connects each tooth root to the surrounding bone) and compresses the gum tissue itself.
Repeated clenching creates micro-injuries in both the gums and the bone beneath them. Each individual episode is minor, but the cumulative effect weakens the structures that hold the gum in place. The tissue loses its ability to heal fully between episodes, and over time the gum pulls away from the tooth. Recession from bruxism often appears on teeth that bear the heaviest bite forces, and it frequently occurs alongside tiny fracture lines in the enamel or flattened, worn-down tooth surfaces.
How Hormones Affect Your Gums
Hormonal shifts during pregnancy, menopause, and puberty change the way gum tissue responds to even small amounts of plaque. During pregnancy, rising estrogen and progesterone amplify the inflammatory response. Gums become more vascular, swell more easily, and bleed at the slightest provocation. This is pregnancy gingivitis, and while it usually resolves after delivery, repeated or severe episodes can weaken the gum’s attachment.
Menopause poses a different threat. Declining estrogen levels impair collagen production in the gums, thin the tissue, and accelerate bone loss in the jaw. The immune environment also shifts toward a more inflammatory state, which means the same amount of plaque causes more damage than it would in a premenopausal woman. Estrogen deficiency also reduces saliva production, removing one of the mouth’s key defenses against bacterial buildup. Less saliva means more plaque, a more acidic environment, and a higher risk of the chronic inflammation that drives recession.
Smoking and Reduced Blood Flow
Smoking contributes to recession through two separate pathways. First, the chemicals in tobacco smoke are directly toxic to gum cells and promote the same collagen-destroying enzyme activity that bacteria trigger. Second, nicotine constricts blood vessels in the gums, reducing blood flow to the superficial layers of tissue. Research using laser blood flow measurements has confirmed that even heated tobacco products decrease circulation in the gum’s surface layer.
Reduced blood flow means less oxygen and fewer immune cells reaching the tissue, which slows healing and weakens the gum’s ability to fight infection. It also masks the warning signs. Healthy, well-supplied gums bleed when they’re inflamed, which is an early alert. Smokers’ gums often don’t bleed despite significant disease underneath, so the problem can advance further before anyone notices.
Other Contributing Factors
Tooth position matters. A tooth that sits outside the natural arch of your jawbone has thinner bone and gum tissue on its outer surface, making it more vulnerable to recession. This is common with crowded lower front teeth or teeth that have shifted after orthodontic treatment.
Thin gum tissue is partly genetic. Some people inherit a thinner, more fragile type of gum (sometimes called a thin biotype) that recedes more easily under the same conditions that wouldn’t affect someone with thicker tissue. Lip or tongue piercings that rub against the gum line can also wear through tissue over time, particularly on the inner surfaces of the lower front teeth.
How Recession Is Classified
Dentists and periodontists categorize recession based on how much attachment has been lost and where. The Cairo classification, widely used in clinical practice, sorts recession into three types. In the mildest form, the gum has receded on the outer surface of the tooth, but the tissue between teeth remains intact. In moderate cases, the attachment loss between teeth is equal to or less than the loss on the outer surface. In the most advanced form, the bone and tissue loss between teeth exceeds the loss on the outer surface, which generally means the recession is harder to reverse with grafting procedures.
This classification matters because it predicts how much root coverage a surgical procedure can realistically achieve. When the bone and tissue between teeth are still intact, grafting procedures can often restore the gum line close to its original position. Once that interproximal support is gone, full coverage becomes unlikely, which is why catching recession early gives you more options.
Why It Tends to Get Worse With Age
Recession is cumulative. Every year of plaque exposure, brushing trauma, clenching force, or hormonal change adds to the total. The collagen in gum tissue also becomes less resilient with age, remodeling more slowly and repairing less completely. Medications common in older adults, particularly those that cause dry mouth, remove the protective effect of saliva and accelerate bacterial damage. The result is that mild recession in your 30s can become significant exposure of root surfaces by your 60s if the underlying causes aren’t addressed.
Root surfaces exposed by recession are softer than enamel and more prone to decay. They also lack the insulating layer that protects the nerve inside the tooth, which is why recession often causes sensitivity to cold, heat, or touch. Keeping exposed roots clean without further traumatizing the gum requires a careful balance of thorough but gentle hygiene, and in many cases, professional treatment to stabilize or reverse the tissue loss.