Amalgam has been used successfully for decades and studies have shown that amalgam fillings can last decades with proper oral hygiene. There has never been a single peer reviewed study showing any correlation (let alone causation) between amalgam and any health issue. Survey after survey shows dentists would prefer amalgam fillings in their own mouths as opposed to composites due to its strength and longevity.
Composites (white fillings) start liquid and are hardened with a blue light. During this change, the composite shrinks a little bit. On front teeth with small cavities, the shrinkage is negligible. But for back teeth that have large cavities and therefore need a lot of composite, the shrinkage is larger. This can create a space that allows bacteria to grow and reform a cavity. In addition, any contamination from saliva will cause the composite to not harden properly. Front teeth usually have smaller cavities than back teeth and contamination is much easier to control, making composites a great filling material for front teeth.
For most people, as long as it has fluoride in it, all toothpastes are pretty much the same. Pick one with a flavor you like. If you have gum disease, Colgate Total and Crest Pro Health have extra ingredients to help fight this disease and may be recommended. If your teeth have occasional sensitivity to cold, Sensodyne has an extra ingredient to help with this problem.
All dentists follow the ALARA principle — As Low As Reasonably Achievable. The amount of radiation used for dental radiographs is very low. A plane trip from New York to Los Angeles will expose you to more radiation than several radiographs. In fact, the masonry in a brick house emits an amount of radiation in a year that is about ten times larger than the amount used in a periapical radiograph!
There is a saying in the dental community — "Floss the ones you want to keep.” A tooth has (5) sides—the chewing side, cheek side, tongue side, front and back. A tooth brush can only reach (3) of those sides. Unless you want to clean only 60% of your mouth, flossing is needed. Not flossing can lead to cavities and gum disease.