Dental amalgam is a stable dental alloy and is a safe, commonly-used restorative material. Amalgam restorations can withstand very high chewing forces. Disadvantages are possible short-term sensitivity to hot or cold after the filling is placed and a restoration that is not natural-looking. The dentist may also need to remove more tooth structure to accommodate an amalgam restoration than would be removed for a composite restoration which may, over the long haul, weaken the teeth in certain situations. Composite restorations are a mixture of glass and quartz-filler in a resin medium and provide a tooth-colored restoration. Composites can be adhesively held in a cavity, usually allowing the dentist to remove less tooth structure than for an amalgam restoration.