An adult should go see a dentist every 6 months just like a child should see a dentist every 6 months.
However not everyone has dental insurance or can afford to see a dentist as often as they should and if so you should try to see a dentist at least once or twice per year.
But preferably a dental checkup for adults should be done every 6 months to keep your teeth healthy and clean and prevent tooth decay.
You should also floss your teeth, brush your teeth and even use mouth wash and do oil pulling to help prevent tooth decay, gum disease, tooth infections etc.
If you do have a tooth infection you should see a dentist because sometimes tooth infections may cause other health issues.
I see my dentist every 6 months and so does my own kids.
A child should see a dentist every 6 months as a preventative measure.
When you take your child to the dentist the child's pediatric dentist will recommend another dental checkup visit 6 months after the first dental checkup and then every 6 months after that.
Make sure your child is brushing their teeth and flossing to keep their teeth clean and free of bacteria, food etc.
This helps prevent cavities, tooth decay, gum disease etc.
A child should be supervised while brushing their teeth until they are at least 6 to 7 years old.
After the child gets to 6 or 7 years old and above they can safely brush their teeth on their own.
Although if your kid is like mine I have to make sure he brushes his teeth even though he's 8 years old I have to sometimes brush his teeth for him because sometimes he will never brush his teeth unless I force him.
My kids all see the dentist for cleanings and a dental checkup every 6 months unless they have another dental issue such as a tooth infection then they see the dentist when needed.