Dentist and Paleo and Gut Bacteria

"Today, over 95 percent of all gum disease and tooth decay is caused by harmful bacteria in our mouths. And harmful bacteria in our mouths are created by harmful bacteria in our gut. And harmful bacteria in our gut are increased by certain foods we eat—specifically dense carbohydrates and refined sugars—those highly processed, refined, hybridized, and genetically modified “foods” of modern-day lifestyles." (link)
 The above is a quote from an article I found on The Paleo Diet website. It is talking about typical dental issues such as, cavities and gum disease. I took both my children to the dentist yesterday and this made me think of this article that I came across last week. My daughter who is 8 may need some orthodontic help at some point, but other than that her teeth are fine. Now, my son, who is almost 6, already had two cavities filled last year and now he has another cavity and then "staining" on his teeth that will become cavities. After the $600 to fill the last two, I was determined to brush and floss his teeth everyday to prevent this. However, despite my effort, he is still getting cavities! He's only 5. What happens at 35? My husband is very diligent about brushing and flossing and his teeth are worse than mine. He has a lot of fillings and root canals. I didn't have any dental problems until I was about 16 and then I started getting cavities. I had a dentist break a filling, which lead to a root canal and for some reason I should pay for that? I digress.

This made me think about the role of diet. My daughter and son eat very differently. Yes, they both love candy and cookies, but my son loves bread and rice and cereals. My daughter loves the Paleo way of eating. She eats a lot of fruits and vegetables and meats.

The article brings up the point that if our species, which depends on teeth to eat and thus survive, had rampant gum disease and tooth decay, this species would become extinct. It also mentions that animals in the wild do not have dental problems, but in captivity where the diet is not their natural diet, do have dental problems.

I am going broke over here with dental costs. I need another solution. I do not buy candy and cookies for my kids anymore. However, I do make cookies for them which whether "Paleo-ish" or not could be a problem. My son polished off all his Halloween candy recently, despite my efforts to control the amounts. He would climb up on the counter and get it down or climb up my closet shelves. Basically, wherever I hid it, he found it. I do buy bread and rice and potatoes to include with my son's meals, because he likes them so much. He demands it. And I don't know what to do about this. I haven't bought bread for about two weeks and he still begs for it at the grocery store. He begs for cereal. He threw in a bag of croutons that I didn't notice just two days ago. I also have a problem of him getting the foods I don't want him to eat elsewhere, such as the rice and sprite from my husband's mother, jelly sandwiches from my mother and pizza at his religious classes on Saturday.

How can I reduce the processed starches and rice and potatoes in my 5 year-old's diet, when he refuses to eat the meat and vegetable dishes I make. How can I stop the sabotage of the standard Western or even Mid-eastern diet from outside the home?