Dental caries is often due to non-fluoridated water, genetics and poor hygiene. BTW raised in England, I have better teeth than most of my US neighbors. In school, we were taught to use correct grammar, enunciate each word according to the Oxford dictionary and encouraged to lose any regional accent. Villages, towns and counties had recognizable dialects which were both a source of pride (or ridicule) and considered ‘charming’ (or uneducated). Most Brits can identify your village/County of origin just by your speech pattern and pronunciation. BBC announcers do not use ‘posh’ English - they affect a bastardized Cockney/Cambridge hybrid. e.g. Piers Morgan.