Autofac. Dispose or not Dispose that is the question

Is there a difference in performance or best practices between the two examples?

Example1:

private void Teste()
{
    using (var scope = Container.BeginLifetimeScope())
    {
        scope.Resolve<MyViewModel>().ShowName();
    }
}

Example2:

private void Teste2()
{
    Resolver.Resolve<MyViewModel>().ShowName();
}