Replacing silver fillings with tooth-colored composite materials is done by prosthodontists for both health and aesthetic reasons. To ensure optimal care for our patients, we are a mercury-free practice. You may find that you have silver/mercury fillings in your mouth, leftover from dental work done in the past. In addition to the less-desirable appearance of silver/mercury fillings, they also present structural problems, resulting in weaker teeth. By contrast, porcelain inlays and tooth colored restorations (onlays) are unnoticeable and actually add strength to weakened teeth.