Childis 12 yrs w/2 cavities in front teeth. We oppose use of flouride. Denist says a composite filling w/small amount of flouride is the best way?

Yes. Absolutely correct response by your dentist. Much greater chance of subsequent decay recurrence, root canal treatment and expensive crown replacement dentistry with out Fluoride composite use.
In my. In my opinion it is very important to use health practitioners that you trust. I would never use a product on my patients if i wouldnt use it on my family. There are other options for fillings that do not contain fluoride. With that being said if your child is at high risk for cavities, Fluoride is very effective in preventing recurrence of decay and slowing/stopping the caries process.
Yes to filings. Fluoride is the single best use of community medicine in the past century. It has many health benefits but, it is the reason cavities have dropped significantly. All bottled water should have the minimum ada recommended amount of fluoride. And yes, any cavity should be filled asap!
Correct. Despite lots of hype, small amounts of systemic Fluoride (what would be released by this type of filling) is perfectly safe. Fluoride's benefical affect on teeth is topical. The very small amount of Fluoride in this filling is being "held up close to the tooth" where is is most needed. If your child is prone to cavities you might want to reconsider using a topical Fluoride to help prevent them.
Believe it or not. If you don't believe your dentist, there may be a better path for both of you. He/she has recommended that type of filling because real science shows less decay over the next few years with that type of filling (& this option often used in "holistic" dental care may be best). Discuss further options or get a 2nd opinion. Audit your child's diet thoroughly as this is the major factor in decay.
Fluoride is great! You are allowed your opinion about fluoride, but is there is no scientific evidence that demonstrates that in the appropriate amounts it is harmful. In fact, the data demonstrates that Fluoride is actually beneficial for both teeth and bones. Let your dentist place those fillings. Remember, we need daily exposure to the sun to produce vitamin d, but to much sun will cause skin cancer!
Prevents recurrent . Fluoride makes the enamel less likely to decay. Your child is at a high risk of additional decay in the same area.