Why Does My Kid Have Tooth Decay

By 2021-06-08 17:39:44

Dr Haifeng Jia from Jiahui Health discusses why sugar isn't the only thing that can cause tooth decay.

People often say, “sugar causes cavities!” But if that’s true, how is it that children who never eat sugary foods can still get cavities?

In fact, what really causes tooth decay is not the habit of eating sugar and sweets, but incomplete and improper teeth cleaning, which allows for the growth of bacteria.

According to the results of the Fourth National Oral Health Epidemiological Survey, only about a quarter, 24.1 percent, of 5-year-olds and about a third, 31.9 percent, of 12-year-olds brush their teeth twice a day.

The prevalence of permanent tooth decay in 12-year-old children is about one third, 34.5 percent, and the prevalence of deciduous tooth (commonly known as baby teeth) decay in 5-year-old children is a sizable 70.9 percent, which is at least 5.8 percent higher than 10 years ago.There is an increasing trend of tooth decay among children, and oral health education still needs to be strengthened.

So what should we do to protect children from tooth decay?

The source of tooth decay

Bacteria + Food + Host + Time

Tooth decay is due to the formation of a film on the tooth surface after eating.


When sugars and starches aren’t cleaned off your teeth, bacteria quickly begin feeding on them and form plaque. Plaque that stays on your teeth can harden under and above your gum line into tartar (calculus). Tartar is quite hard, making this type of plaque more difficult to remove, creating a shield for bacteria.

Bacteria on the tartar then begins to damage the teeth. Acid-producing bacteria will remove calcium from the tooth surface. After a period of time, the tooth surface will soften and collapse to form cavities.

To put it simply, tooth decay happens when you fail to clean your teeth after eating. The food residues combine with bacteria in your mouth to produce acid that will slowly erode your teeth, and over time will lead to decay such as cavities.



How to stop tooth decay

It’s not possible to have a completely sterile oral cavity nor is it natural, so it’s necessary to control the other three factors of “food”, “host”, and “time” to stop the tooth decay process.

Food: Eating sweets does not automatically mean you will get cavities or other forms of tooth decay, but the bacteria that cause tooth decay do feed on the carbohydrates in sugary foods. Eating less sugar means they have less to eat as well.

Host: Refers to saliva and the texture of the teeth themselves. Take steps to seal pits and fissures in teeth so bacteria have fewer places to set up home and grow.

Time: This refers to the amount of time that the bacteria has to sit on your teeth. The longer you go between cleans, the more acid and plague are accumulated. Therefore, if you want to avoid tooth decay, you must brush and floss regularly.


Protect your child’s teeth

So what can you do to ensure that your child has healthy, clean teeth?

Regular cleaning, regular examination

Professional outpatient cleaning

Baby teeth should be cleaned regularly and thoroughly by a professional dentist every 6 to 12 months to remove any plaque or tartar that may have formed on the tooth surface.


Brushing and flossing twice a day

Teach them how to brush properly

Make sure they brush their teeth correctly, at least twice a day.

Before the child is 7 years old, you should brush their teeth for them.

After seven years of age, you can transition from brushing for them, to watching them as they brush, eventually allowing them to brush their teeth on their own.


Use of toothpaste

Try to use about a rice grain-sized amount of fluoride-free toothpaste for children under three years old.

A soybean-sized amount of fluoride toothpaste is recommended for children over three years old.


Use of dental floss

After brushing your teeth every day, floss between every tooth.

Pit and fissure sealing + fluoride coating = double insurance for dental care

Apply fluoride to make teeth stronger

Fluoride acts on the surface of the teeth to prevent the teeth from being corroded by acid and prevent tooth decay.

During the early stages of tooth decay, fluoride can replenish lost surface minerals and restore teeth.

There are three forms of fluoride coating in the clinic: fluoride gel, fluoride foam, and fluoride protective varnish.

Among them, fluoride foam is most suitable for children over three years of age who can gargle. They only need to bite down on a mold full of fluoride foam for 2 to 3 minutes, once a year.

Seal pits and fissures in the teeth, making them easier to clean

The pits and fissures of newly grown teeth are relatively deep and narrow, making them difficult to clean and more likely to harbor the bacteria that cause tooth decay. Preventative sealing can be used in narrow and deep areas to stop this decay from occurring.

Sealing can be used during the emergence of new molars at age three, again at age six, and when the permanent molars emerge at age twelve.


Dr Haifeng Jia, DDS
Dr Haifeng Jia graduated from Shanghai Jiao Tong University School of Medicine major in dentistry. Afterwards he completed the study of periodontology and endodontics at Peking University Health Science Center. He has over 14 years of clinical experience in dentistry and specialises in general dentistry, root canal therapy, paediatric dentistry, and cosmetic dentistry.

Jiahui Health
Phone: 400 868 3000
Website: www.jiahui.com/en/