Silicate Filling Material
De Trey Brothers (estab. 1899, closed 1924)
De Trey's craze proof filling material for anterior teeth. Fissure sealants were made from a resin called BIS GMA. The enamel of the tooth was etched with acid to make it adhere. The resin then shrank onto the tooth quite intimately. The manufacturers introduced a filling material called composite resin based on BIS GMA but no etching.
The donor, John Brownbill, was aware of its great potential for leakage (via shrinkage) and so never used composite resin without etch. Instead, being the last dentist to use silicate until glassionomer was introduced in the 1980s.