Periodontitis is a serious gum infection that damages the soft tissue and bone holding your teeth in place. Left untreated, it gradually destroys the jawbone around affected teeth, eventually causing them to loosen or fall out. It affects nearly half (42%) of all adults aged 30 and older in the United States, making it one of the most common chronic conditions, though many people don’t realize they have it because it often progresses without obvious pain.
How Periodontitis Starts
Periodontitis almost always begins as gingivitis, a milder form of gum disease. Gingivitis causes red, swollen gums that bleed when you brush, but it doesn’t damage the underlying bone. At this stage, the condition is reversible and sometimes goes away on its own with improved oral hygiene.
When gingivitis lingers, bacteria begin migrating below the gumline. The gums start pulling away from the teeth, forming gaps called periodontal pockets. In a healthy mouth, the space between the gum and tooth measures 1 to 3 millimeters. As periodontitis develops, those pockets deepen beyond 4 millimeters, and pockets deeper than 5 millimeters can no longer be cleaned with regular brushing or flossing. A layer of bacterial plaque builds up on the root and neck of the tooth, where it hardens into tartar that only a dental professional can remove.
The real damage isn’t caused by the bacteria alone. Your immune system ramps up inflammation to fight the infection, and that inflammatory response itself breaks down gum tissue and bone. Certain bacteria, particularly one called P. gingivalis, can actually suppress parts of your immune defense while still triggering the destructive inflammation. The result is a cycle: bacteria thrive, the immune response intensifies, and tissue is destroyed in the process.
Symptoms to Watch For
Periodontitis often causes no noticeable symptoms until it reaches an advanced stage. That’s what makes it dangerous. When signs do appear, they include:
- Swollen, puffy gums that are bright red, dark red, or dark purple
- Gums that bleed easily during brushing, flossing, or sometimes spontaneously
- Receding gums that pull away from the teeth, making teeth look longer than usual
- Persistent bad breath that doesn’t go away with brushing
- Pus between teeth and gums
- New spaces between teeth that appear as dark triangles
- Loose teeth, shifting teeth, or pain when chewing
A pink-tinged toothbrush after brushing is an early signal many people dismiss. Tenderness when touching the gums is another clue, though periodontitis can be painless for years before it becomes obvious.
How It Progresses
Periodontitis doesn’t advance in a steady, predictable line. It moves in episodes: short phases of active tissue destruction followed by longer quiet phases where the disease plateaus or even recovers slightly. But it never resolves on its own. Without treatment, the overall trajectory is downward.
In the earlier stages, pocket depths increase and gum tissue pulls back. As it advances, the infection attacks the jawbone itself, exposing parts of the tooth roots. Teeth may shift position, become painful to chew on, and eventually loosen to the point where they need to be removed. Severe periodontitis affects about 8% of adults.
Risk Factors Beyond Brushing
Poor oral hygiene is the most obvious risk factor, but it’s far from the only one. Smoking is one of the strongest contributors. Research shows that smoking doesn’t just increase the risk of periodontitis on its own; it interacts with your genetic makeup to amplify the damage. In people who carry certain genetic susceptibility variants, tobacco smoke directly alters the activity of genes involved in bone growth, tissue repair, and immune response. One affected gene is a negative regulator of bone growth, meaning smoking can accelerate the bone loss that makes periodontitis so destructive.
Genetics play an independent role as well. Some people are simply more prone to aggressive immune responses that damage gum tissue, even with decent oral care. Other risk factors include diabetes (which has a two-way relationship with periodontitis), hormonal changes during pregnancy or menopause, medications that reduce saliva flow, and conditions that weaken the immune system.
Links to Heart Disease and Diabetes
Periodontitis is not just a mouth problem. The inflamed, ulcerated tissue inside periodontal pockets acts as a direct entry point for bacteria into the bloodstream. From there, those bacteria can reach other organ systems.
People with periodontitis have a meaningfully increased risk of cardiovascular problems, including heart attack, heart failure, stroke, and atherosclerosis (hardening of the arteries). The connection appears to involve both the bacteria themselves and the chronic systemic inflammation periodontitis generates.
The relationship with diabetes is especially notable because it runs in both directions. Diabetes makes periodontitis worse, and periodontitis makes blood sugar harder to control. The encouraging side of this link: treating periodontal disease has been shown to reduce glycated hemoglobin levels (a key marker of long-term blood sugar control) in people with diabetes.
How Periodontitis Is Diagnosed
Dentists diagnose periodontitis using a small ruler called a dental probe, which measures the depth of the pockets between your gums and teeth at several points around your mouth. Pockets of 1 to 3 millimeters are healthy. Pockets deeper than 4 millimeters suggest periodontitis. X-rays show how much bone loss has occurred around the teeth, which helps determine the severity.
Because periodontitis is painless in its early stages, it’s frequently caught during routine dental visits rather than because of symptoms you noticed yourself. This is one of the main reasons regular dental checkups matter, even when nothing feels wrong.
Treatment Options
Non-surgical cleaning below the gumline is the foundation of periodontitis treatment. The procedure, called scaling and root planing, involves removing bacterial plaque and hardened tartar from the tooth surfaces below the gum and smoothing the root to help the gums reattach. This is typically done one section of the mouth at a time over several weeks, or in some cases across two visits within 24 hours as a full-mouth approach. An antimicrobial rinse like chlorhexidine is sometimes used alongside the cleaning to further reduce bacteria.
For mild to moderate cases, this deep cleaning is often enough to halt the disease and allow the gums to heal. You’ll typically have follow-up visits so your dentist can re-measure pocket depths and check whether the tissue is recovering.
When pockets are too deep or bone loss is too severe for non-surgical treatment to work, surgery may be needed. Procedures range from flap surgery (lifting the gums back to clean underneath, then securing them closer to the tooth) to bone and tissue grafts that help rebuild what’s been lost. The specific approach depends on how advanced the disease is.
Preventing Recurrence
Periodontitis requires ongoing management even after successful treatment. The bacteria that caused it will recolonize if you stop maintaining your oral hygiene. Brushing twice daily, flossing or using interdental brushes to clean between teeth, and keeping up with professional cleanings (often every 3 to 4 months rather than the standard 6 for people with a history of periodontitis) are the core of long-term control.
If you smoke, quitting is one of the most impactful things you can do. Smoking both increases the severity of periodontitis and reduces how well your gums respond to treatment. Managing blood sugar if you have diabetes also helps, given the two-way relationship between the conditions.