Japan Offspring Fund (JOF) Monthly Newsletter
September 2005, No.197

* Baby pacifiers and teeth problems

We talk to Dr. Kameyama, who discovered that in every case where children had crooked teeth and other deformities, it turned out that they were using pacifiers. He recommends that children should not use pacifiers after reaching the age of 1.

* Tuna: recommendations for pregnant women

The Japanese government has issued recommendations regarding the safe intake of maguro (tuna), aimed at pregnant women. Take care and do not eat too much, as there is a risk concerning dimethyl mercury levels. If we consider ordinary sushi or sashimi, one piece is usually about 15 gram, so it would be considered safe to eat up to 5 pieces.

Baby pacifiers and teeth problems

Japan Offspring Fund talked about baby pacifiers with Dr. Kameyama

Q: You have made some very serious discoveries at your clinic. Tell us about your findings. At what point are pacifiers clearly a problem?

A: I noticed that children who have used pacifiers have deformed teeth. In my opinion, at 3 years old, the child should never use a pacifier. It is often recommended as a way to get the baby to stop sucking its thumb. However, using a pacifier will damage and deform the teeth. I was surprised to find that pacifiers are also recommended as a way to get the baby to breathe through its nose. This is even written on the piece of paper that comes with the package of the pacifier.

Q: Please give a few examples.

A: Before, I held the view that teeth problems such are misaligned teeth and other deformities are inherited or innate. Thus I never asked parents if the child used a pacifier. Then I discovered that in every case where children had crooked teeth and other deformities, it turned out that they were using pacifiers. I searched for this in the dental literature, but there was nothing written about it at all. So, I started putting information about this on my homepage, so parents would understand what a problem it is.

A: Is there no balanced information at all?

Q: Well, actually I got so angry while I was discovering this problem. An article even appeared in a dental magazine, to promote pacifiers. At that time, I was having so many patients with problems.

A: What happened after that?

Q: The media got interested in the issue, and there were articles in newspapers and even TV programs, discussing the problems connected with pacifiers. Simultaneously, the Tokyo Dental Practitioner's Association started taking the issue seriously. In January 2005, a research committee of pediatrics and child dentistry issued its opinion for the first time concerning pacifiers. They stated clearly that pacifiers are not good for the teeth of the children, and recommended that pacifiers should not be used when the child is more than 1 year old. That was their official statement, and this story was picked up by Yomiuri Shimbun ( Japan 's largest newspaper). After that, many parents were voicing their opinion also on the Internet.

Q: How bad is this problem?

A: Many people seem to think that if you stop using the pacifier, the teeth will get better. This is not the case at all. When the pacifier is used up to 1 1/2 years old, there will be damage in about 30% of the cases. When the pacifier is used up to 2 years old, the damage is 60%. When the pacifier is used up to 3 years old, the damage is found in 100% of the children, especially misaligned teeth, deformities and other dental abnormalities. As the teeth emerge from the jaw, they will bend and try to adjust, and the consequences are serious.

Q: It seems we can see pacifiers more often in foreign countries than in Japan . For example, don't you think we often see babies with pacifiers in American movies?

A: Correct. Actually, in 1992, there was a study that linked headaches, fever and diarrhea to the use of pacifiers. The focus in such reports have been on bacterial infections and one study pointed out that in 78% cases, there were infectious bacteria on the pacifiers.

Q: So, in foreign countries, this issue has been known to be a serious problem. Even the New York Times wrote about it in 2002.

A: Yes, and I think it will soon become a major issue also here in Japan .

Q: Do you think a warning would be a good solution, for example to tell parents to please stop letting their babies use pacifiers at the age of 1?

A: Yes. It could also be a good idea to tell parents what will happen if they let the child continue using a pacifier beyond the age of 1. Photographs showing what happens to the teeth should be published, to explain what the effects will be. Furthermore, there should be liability for the manufacturer of pacifiers. They should be forced to pay the dentist's bill for patients whose teeth have been damaged by pacifiers.

Seriously damaged teeth:

Photo 1: This picture shows how the top and bottom teeth are no longer connected. This patient used pacifiers until 3 years old, and has serious problems biting and chewing food.

Photo 2: This patient's jaw slips sideways. When biting with the front teeth has become impossible, the jaw will compensate by moving sideways, thus bending and contorting the face.

Tuna: recommendations for pregnant women

The Japanese government has issued recommendations regarding the safe intake of maguro (tuna), aimed at pregnant women. Take care and do not eat too much, as there is a risk concerning dimethyl mercury levels.

Japan Offspring Fund wrote about tuna in the August issue of our magazine (number 196). On August 12, the Japanese Health Ministry re-issued its guidelines regarding the safe levels of tuna, considering the risks associated with mercury and the brain development of the embryo and the foetus in the womb.

The government's recommendation states that pregnant women, or women who have a possibility of becoming pregnant, should limit their intake of tuna to less than 80 gram twice a week.

If we consider ordinary sushi or sashimi, one piece is usually about 15 gram, so it would be considered safe to eat up to 5 pieces.

This is the second time the Ministry of Health, Labour and Welfare issues recommendations for pregnant women. Last time was in 2003, but that warning was criticized because it did not include an assessment or a guideline for tuna.

The Food Safety Commission has established a tolerance of 2 microgram dimethyl mercury per kg body weight per week. It should be noted that fish is considered very healthy food and superb nutrition for all people. Clearly, noone should eat only tuna, but try to eat many various types of fish.