This was Derby in the 1930s, working class family (her dad was a builder), well-looked-after in general, they had a bathroom and were not neglected or living on the breadline.
They never brushed their teeth.
And their dad told them if they wanted to clean them they should get some soot from the chimney and do it with a finger, or if they didn't like the taste of soot they could use salt.
When she was 8 she saw an advert for toothbrushes and begged and begged her mum to get her one, and her mum finally gave in but she didn't know what to do with it. 
I am
