diff --git a/Machine/WaterJetPageUC.xaml.vb b/Machine/WaterJetPageUC.xaml.vb
index 161cfd4..be33a3d 100644
--- a/Machine/WaterJetPageUC.xaml.vb
+++ b/Machine/WaterJetPageUC.xaml.vb
@@ -9,6 +9,8 @@ Public Class WaterJetPageUC
    ' Riferimento alla MainWindow
    Private m_MainWindow As MainWindow = DirectCast(Application.Current.MainWindow, MainWindow)
    Private m_refWaterjetDbWindowVM As EgtWPFLib5.WaterjetDbWindowVM
+   Private m_sOrigNewMaterial As String = String.Empty
+   Private m_sOrigNewSubMaterial As String = String.Empty
 
    Private Sub WaterJetPage_Initialized(sender As Object, e As EventArgs)
       m_refWaterjetDbWindowVM = New EgtWPFLib5.WaterjetDbWindowVM(m_MainWindow.m_CurrentMachine.sMachDir)
@@ -21,9 +23,17 @@ Public Class WaterJetPageUC
       Me.DataContext = m_refWaterjetDbWindowVM
    End Sub
 
+   Private Sub NewMaterial_EgtOpening(sender As Object, e As EventArgs) Handles NewMaterialNameTxBx.EgtOpening
+      m_sOrigNewMaterial = NewMaterialNameTxBx.Text
+   End Sub
+
+   Private Sub NewSubMaterial_EgtOpening(sender As Object, e As EventArgs) Handles NewSubMaterialNameTxBx.EgtOpening
+      m_sOrigNewSubMaterial = NewSubMaterialNameTxBx.Text
+   End Sub
+
    Private Sub NewMaterial_EgtClosed(sender As Object, e As EventArgs) Handles NewMaterialNameTxBx.EgtClosed
       m_refWaterjetDbWindowVM.sNewMaterial = NewMaterialNameTxBx.Text
-      If String.IsNullOrEmpty(m_refWaterjetDbWindowVM.sNewMaterial) Then
+      If String.IsNullOrEmpty(m_refWaterjetDbWindowVM.sNewMaterial) OrElse m_refWaterjetDbWindowVM.sNewMaterial = m_sOrigNewMaterial Then
          m_refWaterjetDbWindowVM.NewMaterial_Visibility = Visibility.Collapsed
       Else
          m_refWaterjetDbWindowVM.Done("")
@@ -33,7 +43,7 @@ Public Class WaterJetPageUC
 
    Private Sub NewSubMaterial_EgtClosed(sender As Object, e As EventArgs) Handles NewSubMaterialNameTxBx.EgtClosed
       m_refWaterjetDbWindowVM.sNewSubMaterial = NewSubMaterialNameTxBx.Text
-      If String.IsNullOrEmpty(m_refWaterjetDbWindowVM.sNewSubMaterial) Then
+      If String.IsNullOrEmpty(m_refWaterjetDbWindowVM.sNewSubMaterial) OrElse m_refWaterjetDbWindowVM.sNewSubMaterial = m_sOrigNewSubMaterial Then
          m_refWaterjetDbWindowVM.NewSubMaterial_Visibility = Visibility.Collapsed
       Else
          m_refWaterjetDbWindowVM.Done("")