Dentists have learned that the metal fillings in your mouth act much like metal does outside the mouth. Exposed to heat and cold, such as hot coffee or ice cream, the metal fillings in your teeth expand and contract. As they shift, they can actually weaken the teeth they were meant to protect. Often, the expansion and contraction leads to the entire tooth cracking.
Today’s porcelain inlays and composite resins create fillings that not only look natural but also are stronger than materials of the past.