This is the first episode of a two-part BBC documentary about how the British look after their teeth.
BBC reporter Jasmine Harman meets Sam, a talented singer who has been silenced by the look of her mouth. Can lead dentist Serpil Djemal build up her teeth and her confidence so she can sing again?
We also meet Joe, a young man who has the teeth of an old-age pensioner. Serpil must use all her skill and artistic talent to make his mouth match his age.
And the clinic welcomes a family from Birmingham with six kids, all with a seriously sweet tooth! Together they discover the secret to snacking is not about what you eat but when you eat it. And they uncover the truth of how to brush your teeth perfectly.
Dr Chris Van Tulleken continues his investigation to find the latest scientific discoveries that can change how we look after our teeth. He gives himself gum disease to see if a healthy mouth can add years to your life. He also investigates the hidden sugars in food, and finds out if the drinks we thought were harmless are really dissolving our teeth.
