What Prophet Mohammad told us about tooth brushing On the authority of Abu Hurairah, may Allah be pleased with him, reported: the Messenger of Allah( may peace be upon him) said: were it not that I might over-burden my people I would have ordered them to use siwak (tooth-stick) at every time of the prayer, and in another transmit, in every ablution. Narrated by the two Imams of hadith. On the authority of Abdullah ibn Abbas, may Allah be pleased with him, that the Messenger of Allah said: " keep on doing tooth brushing because it cleans the mouth and pleasures Allah" narrated by al- Byhaki and al-Bukhari. And according to Aisha said tooth brushing cleans the mouth and pleasures Allah" narrated by ibn Majah from abi umamah, may Allah be pleased with them. Islamic jurisprudence on tooth brushing: An- Nawawi said it is sunnah and not compulsory in any condition through the consensus of the scholars. Ibn al- Kayyim said: tooth brushing is recommended act for both fasting and non fasting person in any time because it is not specified in hadiths, also it is needed for a person whose fasting in the sake of Allahs pleasure and His pleasure is demanding in fasting than any other time, so purification is the best deed for a fasting person.(2) Tooth brushing and its effect on the health: The mouth is the entry for food and drinks and it is connected to the outer world, therefore it is exposed more to the germs which we call orogerminal group like staphylococci, streptococci, pneumococcus, lactobacillus, bacilli and spirochaeta. These germs are inactive in the healthy person, but it could be contagious and harmful if the food remaining were in the mouth and between the teeth until it ferments by the germs leading to bad smell, tooth decay or salts accretion around the teeth which could result in (dental calculus) or gingivitis and pyorrhea. Furthermore, these germs could move to far areas in the body making various infections like, gastritis, sinusitis or tracheitis and it may cause abscess in different places in the body(3), moreover it may lead to pyotoxinemia or blood full of germs causing pyrectic diseases. It is known that the most important thing to take care of in the mouth is the teeth, thus they have important functions and their diseases have a big impact on the public health. Therefore, tooth brushing" siwaak" can prevent these diseases, in fact the saliva has condensed salts and if they were in a surface that is far from the natural cleaning motions like the tongue movement or unnatural like tooth brushing, these salts will deposit especially in the gum forming dental plaque. Then the germs react with the food remaining, especially sugars that exist in the mouth, forming organic acids that dissolve the enamel then the dentine. The tooth decay becomes bigger when the carelessness of the mouth cleaning continues. Tooth stick: In sunnah it is mentioned that the prophet Mohammad used a tooth stick made of" al-araak" and the araak tree is from the araakic family which is always green. It grows in the hot areas in Aseer and Jeezan in Saudi Arabia, Egypt, Sudan, Goor Al-Saad (near Jerusalem), Yemen, South Africa and India. Fruits grow on this tree; tasty and eatable, when it becomes ripe the tooth stick is taken from its root and small bushes. The miracle of sunnah in tooth brushing "siwaak": An article written in a German magazine (No.4, 1961)(4) for the scientist Rodat, the chief of the germs institute in Rostok University" I read about the tooth stick that the Arab use as a tooth brush in a book written by a traveler who visited their country; he mentioned it in a sarcasm way, thinking that this action indicates retardation in these people who clean their teeth with a piece of wood. in the 20th century, just then I thought maybe there is a scientific secret behind this wooden piece ! The chance came when a colleague in Sudan brought me a number of tooth sticks and I started my researches on them immediately, I crushed it, mixed it with water and put it on culture I realized it had the same effect as pencillin. If people used tooth brushes from hundred years, Muslims have used tooth sticks for more than 14 century. In observing chemosynthesis for the araak tooth stick we will understand the reason behind the prophet choice which came from Allah, the laboratory researches confirm that the tooth stick, taken from al-araak, contains bog amounts of gall and it is an antiseptic substance which cleans and stops the ulemorrhagia and strengthen it, also the existence of Sinnigrin, a substance that has a very strong smell and taste which helps getting rid of germs (5). The microscopy on the tooth stick results that there are silica crystals and acidosis calx which is useful in getting rid of stains and dental calculus. In addition, Dr.Tariq al-Korey (6) says that there is chloride with silica; these are substances that provide extra whitening, also a gummatous substance which covers the enamel and protects the teeth against cariosity.It is shown that vitamin C and amine trait the damages on the gum, and sulfuric substance that fights cariosity.