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 is the capital of the PeopleÂ´s Republic of China and is located in the north of the. country. It is a very old city, founded over 2,000 years ago.It has 8.5 million inhabitant s in its. urban area and it is China's second largest city in terms of population, after Shanghai. It is also.