Is there a way to hide the contextmenu on a ribbon?

I've tried this with a creation filter, but I can only remove the child elements, but not the parent ToolbarListMenuControlUIElement, so an empty "context menu" is still shown

        #region IUIElementCreationFilter Members

        public void AfterCreateChildElements(UIElement parent)
        {
            if (parent is ToolbarListMenuControlUIElement)
            {
                parent.ChildElements.Clear();
            }
        }

        public bool BeforeCreateChildElements(UIElement parent)
        {
            return false;
        }

        #endregion