cant overload the dispose method of a picturebox

[MrPolite]

I have a class which inherits from PictureBox. I want to overload the Dispose sub, but I can't.

Public Overloads Overrides Sub Dispose()
    End Sub

when I run my app, it gives me this error:
An unhandled exception of type 'System.TypeLoadException' occurred in Paint Mall.exe

Additional information: Declaration referenced in a method implementation can not be a final method. Type: PaintMall.Ruler. Assembly: Dispose.