Once you find a PDF (or any format) of the story, here's what you might expect and how you can use it:

Searching for is the first step toward turning toothbrushing from a chore into a game. Whether you find a free library scan, purchase the official eBook from Thienemann, or use a read-aloud video, this story remains one of the most effective dental health tools ever written.

Some illustrated versions from the 1950s have entered the public domain in certain countries (like Canada or the US for pre-1964 works). Check for scanned copies – try searching "Karius and Bactus English" or "Karius und Baktus 1950."

However, one day, Jens gets a toothache. A dentist (or his mother) introduces a toothbrush with bristles like "trees in a storm." Karius slides down a waterfall of toothpaste foam, and Baktus’ house collapses. The story ends with the two villains fleeing through the drain, but they warn they will return if brushing stops. Jens learns to brush daily, keeping his teeth white and healthy.

Karius and Baktus are characters from a well-known Norwegian book and subsequent adaptations aimed at teaching children about dental hygiene. The story is designed to educate kids about the importance of taking care of their teeth, the consequences of not doing so, and how certain bacteria (like the ones personified by Karius and Baktus) can lead to cavities and other dental health issues.