Dental decay, also known as dental caries, begins first inside the tooth. A white spot appears on the enamel where the tooth has started to weaken inside. At this stage, the tooth can repair the weakened area with the help of fluoride and minerals in saliva.
Beijing, also Peking, is the capital of the People's Republic of China and one of the most populous cities in the world. Its population in 2013 was 21,150,000. The city proper is the 3rd largest in the world.
Beijing â The Capital of China. Urban Population: 18.8 million. As the capital of China, Beijing ranks as the top on the major cities in China. Reputed as the worldâs historical city and one of the top seven ancient capitals in China, Beijing has been the capital of China since Lioa Dynasty, 800 years till now.