I'm 58 and live in Ahwatukee. I've had type 2 diabetes for about six years. At my last physical my A1C was 8.4, and my doctor asked when I'd last seen a dentist. About three years ago, which sounded worse once I said it out loud. My gums bleed when I brush, but I figured that was normal. A friend says dentists push a "deep cleaning" on anyone who walks in, so I'm definately a little suspicious. I'm trying to take my blood sugar seriously, I just don't want another sales pitch. Can fixing my gums actually help my blood sugar, or is that a stretch?
Ray
Dear Ray,
Fair question. Yes, treating gum disease can modestly lower A1C in people with diabetes, especially type 2 diabetes. A Cochrane review found an average reduction of 0.43 percentage points at three to four months compared with no treatment or usual care. Results vary, and gum treatment does not replace diabetes medication or care from your physician.
A1C is also written as HbA1c on lab reports and in research.
Your doctor's question makes sense. Your friend's concern deserves an answer, too. I would want you to understand both the evidence for treatment and the findings in your own mouth before agreeing to anything.
How gum disease and blood sugar affect each other
The connection runs both ways. As the CDC explains, gum disease can be more severe and take longer to heal when you have diabetes. With gum disease, your diabetes may also be harder to manage. High blood sugar can weaken white blood cells that fight infections; when blood sugar is high, sugar in saliva is high, too.
Gum disease is also called periodontal disease. Periodontitis is the form that damages the tissues and bone supporting your teeth.
A review of studies following people over time found that periodontitis was associated with about a 26% higher risk of developing diabetes. Looking the other way, diabetes was associated with about a 24% higher risk of developing periodontitis. Those are associations, not proof that one caused the other. The studies varied considerably, including how they diagnosed the diseases.
I wouldn't use those percentages to predict your future. You already have diabetes; the useful question now is whether you have gum disease that needs care.
Bleeding gums are common, but they aren't "normal" in the sense of something to accept and ignore. Red, swollen or easily bleeding gums deserve a dental visit. You don't need to feel embarrassed about the three-year gap. I'd rather spend our time figuring out what you need now.
Can treating gum disease lower your A1C?
The strongest broad evidence comes from a 2022 Cochrane review of 35 randomized trials involving 3,249 people, nearly all with type 2 diabetes. Researchers compared cleaning below the gumline with no treatment or usual care. That treatment is called scaling and root planing, often shortened to "deep cleaning."
At three to four months, A1C was lower by an average of 0.43 percentage points. That result came from 30 studies with 2,443 analysed participants, and the reviewers judged the evidence moderate certainty. They considered the improvement clinically significant. Modest can still matter.
At six months, the average difference was 0.30 points across 12 studies. The 12-month estimate was 0.50 points, but it came from just one study. That makes me more cautious about promising a lasting blood sugar benefit. Most studies also did not evaluate adverse effects, so the review cannot answer every question about treatment trade-offs.
In a London randomized trial of 264 people with type 2 diabetes and periodontitis, average starting A1C was 8.1% in both groups. The intensive program included cleaning below the gumline, periodontal surgery for some participants, and maintenance every three months. After 12 months, the intensive treatment group had an A1C 0.6 percentage points lower than the group receiving only a basic cleaning above the gumline, after adjustment for starting A1C and other factors. Encouraging, although it was a single-centre trial.
These results support treating diagnosed gum disease as one piece of diabetes care. They do not justify promising you a particular A1C drop or replacing your diabetes medicine, diet or physician's care. I wouldn't ask your gums to take over your doctor's job.
Does your starting A1C make a difference?
It appears to. A 2026 follow-up study tracked 154 nonsmoking adults with diabetes and periodontitis after nonsurgical gum treatment. Their average starting A1C was 8.4%, the same number you mentioned. They also had maintenance visits at three, six, nine and twelve months.
Average A1C was about 0.7 points lower at each follow-up. At twelve months, people who started above 8.0% had a 1.31-point drop, compared with 0.24 points among those starting at or below 8.0%.
Here's the catch: there was no untreated comparison group. We know blood sugar improved alongside gum treatment; we cannot say the treatment caused all of that improvement. I would not subtract 1.31 from your result and call it a forecast. Your starting number puts you in the group where benefit seems greater, but it isn't a promise.
The counterpoint matters. In a small 2026 randomized trial, 100 adults in India already had fairly well-controlled diabetes, with A1C between 6.5% and 7.5%. Scaling and root planing improved their gum health, but A1C did not differ significantly from controls at three months. It was a small, short study. Still, it helps explain why healthier gums may come with little movement in A1C when blood sugar is already near goal.
My view: we should treat gum disease because it needs treatment. A possible blood sugar improvement is another reason to take it seriously, not the only measure of whether caring for your gums was worthwhile.
A deep cleaning needs a reason
Your friend is right to expect an explanation. A diabetes diagnosis alone is not my reason to recommend deep cleaning. Neither is the fact that you haven't been in for a while.
I recommend scaling and root planing only when an exam, gum measurements and X-rays show pockets and bone loss that call for it. Ask your dentist to explain those findings. "Because you need one" isn't much of an explanation, is it?
If your gums just need a regular cleaning, that's what you get. My preference is the least invasive option that actually works. Conservative care means matching treatment to what we find, and being candid about the benefits, uncertainties and trade-offs before you decide.
Our periodontal care page explains how we assess and care for gum disease.
Maintenance matters, too. The people in that follow-up study kept coming back for maintenance visits; it wasn't one cleaning and done. How often you come back is something we'd decide together, based on what we find.
What I would do next
The American Diabetes Association's 2026 standards recommend a dental exam at least once a year for people with diabetes. Here is where I would start with you:
- •Arrange the exam and tell your dentist you've had diabetes for about six years, along with which medicines you take.
- •If you use insulin or a sulfonylurea, discuss medication timing with your doctor before longer procedures. For a routine visit, eat normally; if sedation or fasting is planned, follow your clinicians' food and medication instructions. Bring your glucose meter, and don't change medicines on your own.
- •If you smoke, seek help quitting. Smoking increases gum disease risk and can worsen diabetes.
- •Share your gum findings and treatment results with your physician so they can see the full picture.
Some diabetes medicines carry a risk of low blood sugar during dental procedures. The standards call for medical and dental treatment plans to be coordinated as needed, including medication adjustment and glucose checks. That is a reason to plan with your clinicians, not skip the visit.
This conversation comes up often with patients in Ahwatukee and Chandler. The Arizona Department of Health Services report says roughly one in eight Arizona adults reported diagnosed diabetes in 2022 and estimates about one in three adults have prediabetes. November is National Diabetes Month, but any month is a good time to book your exam. No lecture required.
Call Kokopelli Family and Cosmetic Dentistry in Ahwatukee at (480) 283-0733, or Kokopelli Dentistry of Chandler at (480) 895-3252, to request an appointment. Bring your latest A1C and medication list, Ray. Let's find out what your gums actually need.
Sources
- •1. Centers for Disease Control and Prevention. Oral Health and Diabetes. 2024. Link
- •2. Stöhr J, Barbaresko J, Neuenschwander M, et al. Bidirectional association between periodontal disease and diabetes mellitus: a systematic review and meta-analysis of cohort studies. Scientific Reports. 2021;11(1):13686. PubMed
- •3. Simpson TC, Clarkson JE, Worthington HV, et al. Treatment of periodontitis for glycaemic control in people with diabetes mellitus. Cochrane Database of Systematic Reviews. 2022;4(4):CD004714. PubMed
- •4. D'Aiuto F, Gkranias N, Bhowruth D, et al. Systemic effects of periodontitis treatment in patients with type 2 diabetes: a 12 month, single-centre, investigator-masked, randomised trial. Lancet Diabetes & Endocrinology. 2018;6(12):954-965. PubMed
- •5. Chee HK, Tan SHX, Tjakkes GHE, et al. Long-Term Effect of Periodontal Therapy on HbA1c Changes in Type 2 Diabetes. Journal of Dental Research. 2026;105(1):67-76. PubMed
- •6. Raval R, Bhat M, Giliyar SB, et al. The Effect of Periodontal Intervention on HbA1c Levels in Patients with Type 2 Diabetes Mellitus: A Randomized Controlled Study. Journal of Pharmacy and Bioallied Sciences. 2026;18(Suppl 1):S215-S217. PubMed
- •7. American Diabetes Association Professional Practice Committee for Diabetes. 4. Comprehensive Medical Evaluation and Assessment of Comorbidities: Standards of Care in Diabetes—2026. Diabetes Care. 2026;49(Suppl 1):S61-S88. PMC
- •8. Arizona Department of Health Services. Diabetes Action Plan Report. 2025. Link
- •9. National Institute of Diabetes and Digestive and Kidney Diseases. National Diabetes Month. 2024. Link
Disclaimer: This blog post is for informational purposes only and is not a substitute for professional medical or dental advice, diagnosis, or treatment. Always consult your dentist and physician about your diabetes, medications, and treatment options before changing any part of your care.
Dr. Harveer Kaur, DDS, BDS
Dr. Kaur is the founder of Kokopelli Dentistry, serving patients in Ahwatukee and Chandler, Arizona. She focuses on family and cosmetic dentistry.
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