Cavities: Russian roulette or bad bacteria?
Oral health is not a game of Russian roulette...but rather a question of establishing good bacteria between 6 and 18 months of age, and therefore of appropriate hygiene and diet. A parental effort to avoid the dentist’s drill!
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The dentist’s drill: the word alone is enough to make many of us break out in a cold sweat. And to make us fear a situation that is unfortunately commonplace in our society: 2 billion people suffer from cavities of their permanent teeth, and 514 million children suffer from cavities of their baby teeth. Even though oral diseases are largely preventable, they are very expensive for our healthcare systems. For this reason, researchers are actively seeking ways to counter them. Among the strategies is the oral microbiota.
In fact, our oral health could go hand-in-hand with the presence of certain oral bacteria: the friendly nitrate-reducing bacteria of the genera Neisseria and Haemophilus could ward off dental cavities and (sidenote: Periodontal disease Periodontal diseases affect the tissues that both surround and support the teeth. The disease is characterized by bleeding or swollen gums (gingivitis), pain and sometimes bad breath. In its more severe form, the gum can come away from the tooth and supporting bone, causing teeth to become loose and sometimes fall out Explore WHO ) , while F. nucleatum is thought to be associated with periodontal disease, plaque and bad breath.
But when and how do these bacteria colonize our mouths and determine what happens to our teeth? Very early, seems to be the answer, from a Japanese study 1 published at the end of 2024.
3.5 billion Oral diseases (dental caries, periodontal diseases, tooth loss and oral cancers) affect nearly 3.5 billion people.²
2 billion 2 billion people suffer from caries of permanent teeth and 514 million children suffer from caries of primary teeth.²
Brushing from the first tooth!
At 1 week of age, when the child is fed milk , the oral microbiota appears to be quite immature. But the situation soon changes: between 6 and 18 months, following the introduction of the first solid foods and the appearance of the first teeth, a baby's oral microbiota become comparable to that of an adult!
19% Severe periodontal diseases are estimated to affect around 19% of the global adult population, representing more than 1 billion cases worldwide.²
20% Only 20% of those surveyed in 2024 said they know exactly what the oral microbiota is (+3 points vs. 2023).³
Most importantly, our bacterial allies—Neisseria and Haemophilus—and the dreaded Fusobacterium have already moved in. With a long-term lease: after the age of 36 months, a child's oral microbiota hardly evolves at all.
Thus, everything seems to come into play before the child's 3rd birthday, or even between 6 and 18 months: this short window of maturation of the oral microbiota seems to be essential for the future prevention of oral diseases such as cavities. And for our future dental bills!
In other words, from the age of 6 months and the appearance of the first teeth, oral hygiene and tooth brushing are essential—as is limiting sugar (sweets, syrups, juices, etc.), which feeds cavities!!