There is no property on the ContentPane that would affect the control template for the tab item used to represent it - only the TabHeaderTemplate which is the template for the content displayed within the tab item. If you want to retemplate the tab item then you would create a template for the PaneTabItem. Note by default we use 3 different templates depending on where the PaneTabItem is used. For each there is a resource key that we use to identify them so you could create a custom template using one of these keys - DockableTabItemTemplateKey, DocumentTabItemTemplateKey and UnpinnedTabItemTemplateKey which are all defined on the PaneTabItem class. I would highly recommend using the templates that we provide within the DefaultStyles directory as the starting point for any custom templates you might make.