Birchwood infused with Cinnamon, Tea Tree Oil and Menthol Tea Tree Therapy Cinnamon Toothpicks are made from Birchwood trees treated with Tea Tree Oil and Menthol. Cinnamon (oil of cassia) is added to provide a zesty invigorating flavor. Tea Tree Oils natural antiseptic properties help freshen breath and kill bacteria that causes plaque and tartar. Their long-lasting flavor can be an aid to those giving up smoking.