Porcelain is fused to an underlying metal structure to provide strength to a filling, crown or bridge. Alloy of gold, copper and other metals resulting in a strong, effective filling, crown or bridge. Alloys of non-noble metals with silver appearance resulting in high strength crowns and bridges.orcelain is fused to an underlying metal structure to provide strength to a filling, crown or bridge. Alloy of gold, copper and other metals resulting in a strong, effective filling, crown or bridge. Alloys of non-noble metals with silver appearance resulting in high strength crowns and bridges.
Limit refers principally to the establishment of a maximum beyond which a person or thing cannot or may not go: The Constitution limits the president's term of office to four years. To restrict is to keep within prescribed limits, as of choice or action: The sale of alcohol is restricted to people who are 21 and older.
Definition of boundary. plural. boundaries. : something that indicates or fixes a limit or extent Those two trees mark the boundary of our property. the mountain range that forms the country's northern boundary.