Use the ShowHeader property to control the visibility of the Accordion's header.
You can provide the header glyph template using the HeaderGlyphTemplate property. If you have more than one template that can be used to render the accordion's header glyph, you can implement custom logic to choose the required template. To do this, derive from the System.Windows.Controls.DataTemplateSelector class, implement the SelectTemplate method that returns a template which meets the required condition, and assign it to the HeaderGlyphTemplateSelector property.