The short answer is bacteria. The more useful answer is a lot more complicated than that, and it’s the version I actually give patients, because “bacteria caused it” doesn’t explain why two people with similar brushing habits can end up in completely different places years later. One factor starts the process. Several others decide how far it goes.
I think this question is worth answering honestly rather than simply, because understanding what’s actually driving your specific case tends to matter more for prevention than a generic list of do’s and don’ts.
The Root Cause: Bacterial Plaque
Every case of periodontal disease starts the same way. Plaque, a sticky film of bacteria, builds up on your teeth continuously, and it’s most concentrated right along the gumline. Brushing and flossing remove most of it, but any that’s missed hardens into tartar within a day or two, and tartar can’t be removed with a toothbrush. Once tartar builds up along and below the gumline, it irritates the gum tissue, and that irritation is where inflammation, and eventually periodontal disease, begins.
If bacterial plaque were the whole story, prevention would be simple. Brush well, floss consistently, done. In practice, I see patients with excellent home care still develop periodontal disease, and patients with mediocre home care who never do. That gap is where the rest of this list comes in.
The Factors That Actually Determine Your Risk
Smoking and Vaping
This is, in my experience, the single biggest risk factor beyond plaque itself. Smoking restricts blood flow to the gums, which both accelerates gum disease and makes it noticeably harder to treat, since healing depends on healthy circulation. I see this pattern consistently enough that smoking status is one of the first things I ask about with a new periodontal patient, because it changes both the risk and the treatment plan.
Genetics
Some people are simply more genetically predisposed to periodontal disease, regardless of how well they care for their teeth. If a parent or sibling has a history of gum disease, particularly at a younger age than typical, that’s worth mentioning to your dentist, since it can mean closer monitoring makes sense even with good home care.
Diabetes
The relationship between diabetes and gum disease runs in both directions. Uncontrolled blood sugar makes gum disease more likely and more severe, and gum disease, in turn, can make blood sugar harder to control. This is one of the clearer examples of how periodontal health connects to overall health rather than existing in isolation.
Hormonal Changes
Pregnancy, menopause, and other periods of hormonal shift can increase gum sensitivity and inflammation, sometimes significantly. I see this most often with pregnant patients, where increased blood flow to the gums during pregnancy can lead to a condition sometimes called pregnancy gingivitis, which needs a slightly different approach to manage.
Certain Medications
Some medications reduce saliva production, and saliva plays a real role in controlling bacteria in your mouth. Others, less commonly, can cause gum tissue overgrowth that makes plaque harder to keep under control. If you’re on a new medication and notice changes in your gums, that’s worth mentioning at your next visit.
Stress
Chronic stress affects the immune system’s ability to fight off infection, including the bacterial infection at the root of gum disease. It’s not usually a standalone cause, but I see it as a real contributing factor, particularly in patients going through an unusually demanding period who suddenly show more inflammation than their history would predict.
Poor Nutrition
A diet low in key nutrients, particularly vitamin C, can affect the body’s ability to fight infection and repair tissue, both of which matter for gum health. This tends to be a smaller factor on its own but compounds with the others on this list.
Teeth Grinding
Grinding or clenching doesn’t cause gum disease directly, but it can accelerate the damage in a mouth where periodontal disease is already present, by putting additional pressure on teeth that already have reduced bone support.
Crooked or Crowded Teeth
Misaligned teeth are simply harder to clean effectively, which means plaque and tartar have more places to build up undisturbed, even with a solid brushing routine.
Why Two Patients Rarely Look the Same
This is the part I think is most useful for patients to understand. Periodontal disease isn’t a single-cause condition with a single-path progression. A patient who smokes and has a family history is working against a very different set of odds than a patient with neither risk factor, even if their home care habits are identical. This is part of why I don’t treat every case the same way, and why a treatment plan needs to account for what’s actually driving a specific patient’s risk, not just the current state of their gums.
What This Means for Prevention
Good brushing and flossing matter, but they’re addressing one piece of a larger picture. If you know you’re a smoker, have diabetes, or have a family history of gum disease, that’s information worth actively factoring into how often you’re seen and how closely things are monitored, rather than assuming a standard six-month cleaning schedule covers it. Some patients genuinely need a shorter recall interval based on their actual risk profile, not because anything is currently wrong, but because their risk factors warrant catching changes earlier.
A DFW-Specific Note
A few things about life in this region come up often enough that I’d mention them directly. Texas heat contributes to dehydration more than people account for, and reduced saliva flow from dehydration makes it easier for bacteria to build up. Stress tied to long commutes and a fast-paced job market across the Metroplex is a factor I hear about often when patients describe a stretch of worse gum health than usual. Neither is a primary cause on its own, but they’re the kind of contributing factors worth being aware of if you already have other risk factors on this list.
Where This Leaves You
If you’re trying to figure out why you specifically developed periodontal disease when others around you haven’t, the answer is almost always a combination of bacterial buildup and one or two of the risk factors above, not a single clear cause. Understanding which ones apply to you is genuinely useful, both for treatment and for how closely your gum health needs to be watched going forward.
At ToothHQ Dental Specialists, DFW Metroplex understanding a patient’s actual risk profile, not just their current symptoms, is part of how we build a treatment and maintenance plan for every periodontal patient we see across the DFW Metroplex. If you’re unsure what’s driving your own risk, that’s a reasonable thing to bring up at your next evaluation.
