Every year, over 13 million people worldwide die from stroke. However, many of these incidents could be prevented through relatively simple means, such as a healthier diet, more exercise, or improved oral health.

As many as 25 per cent of the world's population will have a stroke at some point in their lives. While far from all of them are fatal, they can have far-reaching consequences for the individual.

Research shows that up to 90 per cent of strokes are preventable through lifestyle changes. These changes could involve eating better, exercising more or quitting smoking, which most of us are probably familiar with.

But there is a factor that has been shown to play a significant role in stroke patients - and which is perhaps a little more unknown.

- In our study, we found dental bacteria in the blood of four out of five stroke patients. These are bacteria that are naturally present in the mouth. Still, when they get into the bloodstream, they can lead to serious problems, says Olli Patrakka, a researcher at the University of Tampere, Finland.

Previous research has shown that there is a clear link between poor oral health and cardiovascular disease. For example, people who have periodontitis are 28 per cent more likely to have a heart attack. Now, we may be on to something similar when it comes to brain health and stroke.

- Although more studies are needed to establish causality, we now clearly see that dental bacteria also play a significant role in stroke patients. It may have a crucial role in prevention and treatment, says Olli Patrakka.

Stroke is common even in women

Generally speaking, stroke is usually described as something that mainly affects men. But this image is not entirely true. Sixty per cent of people who die from stroke are women, and in the age group 55 to 75, one in five women will have a stroke at some point.

However, because strokes are mainly thought to affect men, many women miss the symptoms, which can lead to seeking care later. Factors that increase the risk of having a stroke include high blood pressure, high blood lipids, smoking and diabetes. However, taking care of your oral health has also been shown to be essential for those who want to prevent stroke.

- The dangerous bacteria in our mouths usually stay there and initially cause 'only' tooth decay. But for those who have periodontal disease, the risk is that these bacteria can travel through the gums and into the bloodstream, says Tommi Pätilä, heart surgeon and founder of Koite Health.

Complementary treatment

The most important measure needed to prevent periodontal disease is regular cleaning of the teeth and the spaces between them. Brushing twice a day and using a floss or interdental brush daily flossing or interdental brushing is a good starting point.

However, mechanical brushing only removes about 65% of the bacteria found on teeth surfaces. A complementary treatment, such as Lumoral, is, thus, recommended for those who want to prevent tooth loss and other serious oral diseases.

Lumoral is a light-activated treatment that utilises a combination of two types of light to remove 99.99 per cent of the bacteria in dental plaque. It is easy to use and also makes it harder for new plaque to stick to teeth.

- Treatments of this type used to be performed only in clinics, but Lumoral has been developed for use at home. It is very effective, and many of my patients with a lot of tartar and inflammation of the gums have felt an incredible improvement after a few weeks of use, says Ing-Marie Albinsson, a dental hygienist at the Lilla Tandkronan clinic in Arvika, Sweden.

Dental and oral bacteria have been linked to numerous chronic diseases throughout the body. Recent research indicates that thorough brushing and regular dental visits can also play a role in preventing strokes (1).

According to statistics from the World Stroke Organization (WSO), over 13 million people globally suffer from strokes each year, with one in four individuals experiencing a stroke in their lifetime. Surprisingly, up to 90% of these cases could be prevented through lifestyle changes such as adopting a healthier diet, increasing regular exercise, quitting smoking, and even improving oral hygiene practices (2).

In his recent doctoral dissertation in forensic medicine at the University of Tampere, Medical Licentiate Olli Patrakka examined the significance of oral bacteria, particularly viridans group streptococci, in stroke development. While these bacteria are normal mouth microbes, they can lead to serious illnesses like heart valve inflammation when entering the bloodstream, such as through inflamed gums during teeth brushing. (3).

Olli Patrakka suggests that these bacteria, attaching to tooth surfaces and initiating plaque formation, may similarly contribute to stroke and atherosclerosis development when entering arterial walls via the bloodstream during dental procedures or infections.

Poor oral hygiene is a risk factor for strokes

According to Patrakka, dental bacteria are present in the blood clots of stroke patients in about four out of five cases, with similar results yet to be reported. Blood clots were collected from stroke patients undergoing acute care in Tampere, Finland, for the study, along with samples from patients with symptomatic carotid artery stenosis used as endarterectomy tissues. (3).

Epidemiological studies have identified poor oral hygiene as an independent risk factor for strokes. Patrakka suggests that the inflammatory reaction induced by dental bacteria in atherosclerotic plaques could explicitly explain this connection.

The dissertation's findings are significant as they present new opportunities for stroke patient treatment development, Patrakka says. He also believes that the development of a vaccine may also be now feasible.

Patrakka stresses that while further research is necessary to establish causality, the study supports the importance of oral health, particularly in individuals at risk of srokes. He emphasizes that considering the inflammation caused by streptococcal bacteria in the mouth is crucial in stroke prevention as part of routine dental care. Moreover, investigating the potential benefits of timely antimicrobial treatment or bacterial vaccines in the future is essential.

Periodontitis is the root cause of many ailments

Studies show dental plaque bacteria are responsible for about 95 per cent of oral diseases. One of the most common oral diseases is periodontitis, a severe gum disease caused by dental plaque. Early signs of this disease include red gums, gum bleeding, and bad breath. (4)

In patients with periodontitis, the fibres that attach the tooth to the gum are destroyed, forming a periodontal pocket between the gum and the tooth. This pocket may expand around the entire tooth. If the infection is not treated promptly and oral hygiene is not improved, it can progress to destroy more extensively the supporting tissues of the teeth and, ultimately, the jawbone. (4)

Thorough oral hygiene is crucial for the prevention and treatment of oral infections. According to the Oral Health Foundation one-in-four (26%) British adults regularly brush their teeth only once a day raising concerns about the number of people willing to skip twice-daily brushing. (5)

The charity is especially worried by the number of people who regularly fail to brush their teeth last thing at night, when the health of the mouth is most likely to deteriorate.  Insights from the research show that one-in-four (25%) do not brush their teeth in the evening before they go to bed. (5).

Deficiencies in oral hygiene are directly reflected in the statistics of oral infectious diseases. More than 45% of adults in the UK are currently being affected by gum disease. Meanwhile, 10% are living with the most severe form, which can lead to tooth loss. (6)

Thorough mechanical brushing of teeth and cleaning of the interdental spaces are crucial because even asymptomatic oral inflammations can affect the body's overall health. According to statistics, individuals with healthy mouths even live longer, research shows (7).

– Every missing tooth reduces life expectancy. This is talked about far too little, says Tommi Pätilä, a heart and transplant surgeon at HUS New Children's Hospital in Helsinki, Finland.

Pätilä is also one of the developers of the antibacterial Lumoral method. Lumoral is a medical device designed to improve oral hygiene and oral health. The antibacterial oral care method is especially suitable for patients with difficult-to-treat gum diseases such as periodontitis who do not get adequate results from traditional oral hygiene methods such as brushing teeth and cleaning interdental spaces. (8, 9, 10).

The effectiveness of the novel oral health enhancing device relies on antimicrobial photodynamic therapy (aPDT), also referred to as photoantimicrobial chemotherapy. While this technology is already prevalent in dental clinics, the advent of a home-use device allows for more frequent application of this antibacterial treatment. (11)

aPDT technology itself utilizes light energy and a photosensitizer to generate an antimicrobial effect that eliminates problem-causing plaque bacteria from the mouth. Due to its targeted approach aPDT does not lead to bacterial resistance. (11)

The importance of interdisciplinary collaboration

According to Pätilä, the recent medical dissertation at the University of Tampere holds significance as it integrates oral health into overall body health. Enhancing collaboration between doctors and dentists is crucial and needs improvement across various European countries. While many medical doctors already evaluate their patients' oral health at clinics and refer them for additional treatment when needed, closer collaboration is essential.

Diabetes serves as a prime example of a disease where the importance of underlying inflammations is widely acknowledged. However, heightened collaboration is necessary to accelerate diagnoses and even prevent several common diseases.

Olli Patrakka's interest in oral bacteria stemmed from his responsibilities as a pathologist. Has the interest of young doctors in the impact of dental infections on general health increased?

– It hasn't increased significantly, but it should. In my basic medical training about five years ago, there was minimal discussion of the impact of dental infections on overall health. While the topic is relatively new, it's crucial that awareness and scientific evidence grow over time.

Patrakka underscores the importance of general practitioners recognizing when a dental issue necessitates a referral to a dentist. This could streamline the treatment of oral infections and potentially aid in achieving a balance in treating various general diseases.

– My research contributes to the growing evidence that oral health significantly influences overall health. The blood vessels of the tooth pulp directly connect to the systemic circulation. Therefore, if teeth are in poor condition, bacteria and their byproducts can circulate directly into our bodies.

References:

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