Children should be watched closely by their parents when brushing their teeth until the age of 14, according to the Royal College of Surgeons.
The organisation, which is made up of a big group of doctors, have made the comments in response to the large number of kids who have rotten teeth.
Teeth problems are the most common reason for kids, aged between five and nine, going to hospital in England.
But the government says children's dental health has improved in the past ten years.
We asked you what you thought about this.
You should be supervised until the age of 14 because you do not know if you have brushed your teeth well. We do not think we brush our teeth well because we forget the teeth at the side and back of our mouth.
Year 2, Chapel St Leonards, Skegness
I think that supervision until 14 is ridiculous. We are old enough to be able to do it ourselves, and we can always ask our parents if we've brushed enough. We don't need supervision.
I'm 10 and I think it's too old for children to be supervised at 14 because they will know how to brush their teeth by then.
Aisha, London, England
I'm 10 yet and I do not get supervised but my parents can here me doing it because I have an electric toothbrush. Sometimes my brother, who is younger than me, needs to be supervised.
Jenny, St Albans, England
I'm 14 and I think that kids do need help brushing their teeth because sometimes they don't know if they have brushed well or not. I have a toothbrush that times the brushing for 2 minutes exactly. I think that instead of children using normal toothbrushes they should use the time brushes instead.
Jessica, London, England