I've always tried to give my children a healthy, varied diet. We've only ever given her sweets, juice etc as treats. However, I did always give her fruit, and especially raisins, as snacks, thinking I was doing the right thing in staying away from processed foods and getting in her "5 a day".
DD is very shy and despite my taking her to the dentist regularly, never opens her mouth properly. I had noticed some discolouration though, so ended up forcing her mouth open at the last dentist visit and it seems she needs a filling, which, because of her not opening her mouth, will have to be done under general anesthetic 
Now the dentist thinks we don't brush her teeth regularly and feed her sweets and drinks all the time!
Is 4 unusually young to have a filling? I don't know of any children that young with fillings, although maybe they have and their parents just don't mention it (I certainly won't be). I'm assuming here that they do white fillings for kids these days.