Fluoride is an element, which has been shown to be beneficial to teeth and help with child preventative dentistry. However, too little or too much fluoride can be detrimental to the teeth. Little or no fluoride will not strengthen the teeth to help them resist cavities. Excessive fluoride ingestion by preschool-aged children can lead to dental fluorosis, which is a chalky white to even brown discoloration of the permanent teeth. Many children often get more fluoride than their parents realize.