In continuation of the world diabetes day on November 14th that intends to raise awareness on this disease, Sunstar sponsored a webinar on the two-way relationship between diabetes and periodontitis commissioned by SEPA, the Spanish Society of Periodontology. Ms. Mayumi Kaneda from the Sunstar Foundation introduced the webinar, since her father engaged the company into research and raising awareness on this link after his own father, the founder of Sunstar, suffered from diabetes himself. Prof. Filippo Graziani discoursed the characteristics of diabetes (type 1 and 2) and periodontitis, how they are a risk for each other and displayed the effect of the periodontal treatment and the institutional actions taken.
Characteristics of diabetes and periodontitis
According to the Global report on diabetes from WHO in 2016, diabetes is on the rise: from 4,7% in the 80s, it skyrocketed to more than 9% in 2019 (463 million people) and is expected to reach a two-digit percentage in 2045 affecting 700 million people, knowing that these numbers are still in the low range as prevalence is underestimated. Diabetes mellitus is a disease marked by disordered metabolism and inappropriate hyperglycemia due to deficiency of insulin secretion and to insulin resistance. When we eat, glucose is sent to bloodstream. At the same time, signals are sent to the pancreas where B cells produce insulin that helps organs, such as muscles and liver, store or use glucose. In diabetes type I, a deficiency of insulin secretion causes the level of glucose in the bloodstream to be above normal. In diabetes type II, insulin may be produced but impaired insulin receptors cause resistance to it. As a result, blood glucose levels start to rise, called hyperglycemia. In subjects affected by diabetes type 1 and type 2, hyperglycemia is above 125 mg/dL and the glycated hemoglobin, HbA1c, is above 6.5%. Patients with diabetes are at higher risk of developing significant complications because high blood glucose levels can provoke cardiovascular diseases, stroke, kidney failure, retina problem and even amputations of the so-called diabetic foot, caused by ischemia and neuropathy. Nearly one out of two deaths before the age of 70 may be related to diabetes.
Periodontitis is a widely spread disease as well: its severe expression affects 8 to 11% of the population but when all the stages of the disease are considered, it is thought that one out of two of the population above 30 may be affected by it. Periodontitis is not a disease of the geriatric population: the peak of incidence is between 30-40 but most of the time the effect of disease is seen at 50-60. Periodontitis can lead to tooth loss and edentulism which is a problem socially, psychologically but also for the quality of life and general health of the patient. The classification defined in 2017 determines four stages and three grades that bring diabetes in the diagnostic: normal glycemia or non-diabetic is grade A, HbA1c <7% is grade B and >7% is grade C.
Diabetes as a risk for periodontitis
More than 25 years ago, periodontitis was defined as the 6th complication of diabetes after retinopathy, nephropathy, neuropathy, macroangiopathy and delayed wound healing. Individuals with uncontrolled diabetes type 2 have three times the risk to develop periodontitis, four times the risk of alveolar bone loss and greater tooth loss when compared to the controlled or the normoglycemic ones. Therefore, uncontrolled diabetes enhances the risk of incidence or progression of periodontitis by 86% and enhances its severity. Subjects with pre-diabetes or subject with a controlled diabetes have the same tendency of developing periodontitis as the ones without diabetes. So, it is not just about having diabetes, it is about having an uncontrolled diabetes that is related to periodontitis.
The biological rationale linking diabetes and periodontitis lies in three main mechanisms:
- Alteration of the microbiological component. Plausible evidence suggests a difference and a shift in the microbial composition of dental plaque towards periopathogens in patients with poorly controlled diabetes.
- Alteration of the host response and the immune cell functions. There is an overall higher tendency for local inflammation in subjects with periodontitis and diabetes both type 1 and type 2, with a higher percentage of inflammatory molecules (interleukins 1β, 4, 7 and prostaglandins) in the gingival crevicular fluid compared to the ones with periodontitis only.
- Hyperglycemia alters wound healing by the production of the Advanced Glycation End products that are associated with enhanced alveolar bone destruction.
Periodontitis as a risk for diabetes
A large study showed that periodontitis in non-diabetic subjects is associated with poor glycemic control, hence a 29% higher risk of developing diabetes within 5 to 13 years. By analyzing the literature, subjects that have periodontitis and diabetes have more complications, especially diabetic retinopathy and cardio-renal ones, than subjects that only have diabetes: the more severe the periodontitis, the more present are microalbuminuria or end-stage renal diseases, in diabetes type 1 and 2.
Cardiorenal death was more frequent in severe periodontitis cases within the diabetes population and subjects that have diabetes and periodontitis have 3.5 more risk to die of cardiorenal problem compared to subjects that have only diabetes without periodontitis. The overall mortality and cardiovascular mortality over 14 years was enhanced by periodontitis in subjects with diabetes type 1 and type 2.
In patients without diabetes, the presence of periodontitis would determine higher levels of HbA1c, fasting blood glucose and even diabetes prevalence and there is a higher risk of developing incident diabetes.
If we unfolded the gingival tissues affected by periodontitis, we would have around 70-80 cm2 of ulcerated tissues that would mean a higher passage of bacteria in the bloodstream and higher level of systemic inflammation. These bacteria might colonize areas like atheromatous plaques and facilitate their rupture. The higher level of systemic inflammation is the link with many different diseases: cardiovascular, metabolic obesity and so forth. Periodontitis is also associated with alteration of the metabolism of the high-density lipoproteins considered as “heart protectors” and dysvitaminosis (lower level of vitamins C and D): this would translate to adipocyte alteration and oxidative stress which would ultimately lead to exacerbation of diabetes by elevated HbA1c.
Effect of periodontal treatment on glycemic control
Patients with diabetes can respond to periodontal treatment almost as somebody without diabetes. In fact, removing the bacterial load is beneficial to them. However, the patients that have been treated for periodontitis and have diabetes will tend to show higher recurrence of pockets if they have uncontrolled diabetes compared to the ones that have controlled diabetes. An uncontrolled diabetes is associated with the diagnosis of grade C that’s why it is crucial to interact with the physician or the diabetologist to try to improve the glycemic control.
The treatment of periodontitis in subjects with diabetes is associated with a reduction of HbA1c of 0.36%, which corresponds to the diminution achieved with a second hypoglycemic medication. In a large landmark study by D’Aiuto et al in 2018, an intensive periodontal treatment even allowed a reduction of 0.9 % of HbA1c in nearly 70 % of the group. This is even supported by insurance companies data: Jeffcoat et al in 2014 showed that providing periodontitis treatment to patients cost less to the insurance companies because they cost them less for other medical reasons later on. The 2020 article by Prof. Genco, the father of the understanding of the link between periodontal diseases and diabetes, showed again that the treatment of periodontitis improves glycemic control in type 2 diabetes (same would be expected in Diabetes Type 1 but there is less data) and subjects with periodontitis and diabetes receiving periodontal treatment incur lower medical costs each year.
A famous trial by Engebretson in 2013 showed no difference in the glycemic control between treated and non-treated patients but the study really showed an important issue: the effect on glycemic control could not be seen because the periodontal treatment failed to reach the accepted standard of care. Hence, the need of a high-quality periodontal treatment.
In their paper in 2015, Prof. Graziani et al. stated there was no difference between full-mouth and conventional approaches in terms of periodontal parameters but in terms of acute inflammation in the first 24 hours: subjects undergoing a full mouth approach have a tremendous systemic inflammation compared to conventional treatment. So, the longer the treatment time, the more inflammation. A similar study in the diabetes population about the timing of treatment is currently in review.
Prof. Graziani finally insisted on the fact that antibiotics are not necessary to treat subjects with periodontitis.
10 years ago, the Italian Society of Periodontology and the two Italian societies of diabetologists acknowledged the need of common strategies and actions and presented their first joint document on diabetes and periodontitis. More recently, in 2018, the meeting of the European Federation of Periodontology with the International Diabetes Federation supported by Sunstar drew specific guidelines:
– Doctors should advise patients and investigate on oral symptoms and refer to the dentist for treatment or at least for a yearly oral screening.
– Dentists should advise all patients with diabetes about the potential implication of periodontitis and patients with periodontitis should be investigated for the presence of diabetes. If there is a risk for diabetes, patients should be referred to their doctors. If the patient has diabetes and periodontitis, a non-surgical treatment should be given without delay. Surgery and implant are possible if the diabetes is controlled.
You can check the materials created by EFP and sponsored by Sunstar here.
This meeting between diabetologists and periodontists was massively endorsed by the diabetologists in their own journals and congresses, but the problem was that diabetic people are hardly seen by diabetologists and rather by family doctors. Therefore, last July, the EFP met with WONKA (the association of the family doctors) and concluded that dentists should assess diabetes in their practice with a country-validated questionnaire to identify patients at risk and if a high risk is detected, patients should be sent to blood testing (a point of care within the practice is possible) in order not to flood family doctors. That would up the chance to detect subjects with diabetes to 70 %. Patients see their dentist more often than their family doctor and given the high proportion of diabetes in subjects with periodontitis, dentists are ideally placed to help identify people at high risk of prediabetes or type 2 diabetes.
See here the recent campaign and decalogue from the Italian Society of Periodontology supported by Sunstar to improve oral hygiene procedures if patients have diabetes.
Watch the full webinar here (available in English, Spanish, French & Italian).