Original: Conducted by Riccardo Muti , the opera house re-opened on 7 December 2004 with a production of Salieri 's Europa riconosciuta , the opera which was performed at La Scala 's inauguration in 1778 .
Simplified: The renovated opera house was opened on 7 December 2004 with the same opera by Salieri that had opened it in 1778 .