The miswak ("miswaak", "siwak", "sewak", or ) is a teeth cleaning twig made from the "Salvadora persica" tree (known as "arāk", أراك, in Arabic). It is reputed to have been used over 7000 years ago. The miswak's properties have been described thus: "Apart from their antibacterial activity which may help control the formation and activity of dental plaque, they can be used effectively as a natural toothbrush for teeth cleaning. Such sticks are effective, inexpensive, common, available, and contain many medical properties". It also features prominently in Islamic hygienical jurisprudence.