Preformed metal crowns (PMCs), sometimes referred to as stainless steel or Nickel Chrome crowns, have been used for restoring primary molars since 1950, and have become the accepted restoration of choice for the primary molar with caries affecting more than one surface, with a proven success rate as a restoration. Although popular with specialists, many clinicians find PMCs difficult to fit using the conventional approach, which requires the use of local anaesthetic injections and extensive tooth preparation. There is also an issue of potential damage to the adjacent first permanent molar when preparing a second primary molar for a PMC. For these, and other reasons, PMCs are not widely used in the UK, forming less than 1% of all restorations provided for children.