Stainless steel crowns are often used in restoring badly decayed deciduous molar teeth. If the decay is small or moderate, a regular filling can be placed to restore tooth anatomy. However, if the decay is extensive and the resulting cavity is large, then the tooth would not be able to support a large filling; it would fracture during chewing. A crown would then be needed. Crowns are tough; they can withstand strong chewing forces.
A stainless steel crown can be contoured to fit over the decayed deciduous tooth after the caries has been removed. These crowns are inexpensive, unlike ceramic or gold crowns, and can function as a medium term restoration for the child, until new adult teeth emerge to replace the decayed tooth.