From VOA Learning English, this is the Health Report.
A new report says nearly four-billion people have major tooth decay, or cavities. That number represents more than half of the world's population. Health officials are warning that failure to repair cavities can lead to social and emotional problems.
Wagner Marcenes is with the Institute of Dentistry at Queen Mary, University of London. He led a team of researchers as part of the Global Burden of Disease 2010 study. About 500 researchers attempt to collect and examine studies about all major diseases. They used the information to estimate rates of the infection.
The report says untreated tooth decay is the most common of all 291 major diseases and injuries. Professor Marcenes says cavities or holes in permanent teeth are also known as caries.
"Caries is a chronic disease that shares the same risk factors as cancer, cardiovascular disease. What we're having now is an increase in disease from highly developed countries happening in sub-Saharan Africa and probably it will be in other areas of Africa, too."
He says an increase in tooth decay in Africa could be a result of developing countries becoming more like Western nations.
"It is likely to be related to a change in diet. Our industrialized diet leads to chronic disease, which includes caries. And that may be the main explanation."
Western diets are rich in sugar, a leading cause of health problems in the mouth. In western countries, water supplies are treated with the chemical fluoride. Adding fluoride to the water makes teeth resistant to the bacteria that can cause tooth decay.
Wagner Marcenes says oral health problems can have a major effect on a person's quality of life. First, cavities make eating difficult. Second, people may change what they eat. They may eat softer foods that are not hard to chew. However, softer foods are often fattier foods.
But professor Marcenes says the biggest issue in tooth decay is both social and mental. He says the researchers found strong evidence that the mouth has a big influence on socialization. He says many people want to hide bad teeth. They smile less and communicate less.
Wagner Marcenes is calling for an "urgent, organized, social response" to the widespread lack of oral health. He believes in a natural method to fight tooth decay by having a healthier diet. He is also calling for the development of new and less costly dental materials and treatments.
And that's the Health Report, I'm Christopher Cruise.
1.cavity n. 腔；洞，凹处
Cavities in teeth are caused by decay.
2.caries n. [口腔] 龋齿；骨疡；骨溃疡
Fluoride can prevent dental caries and it has been applied since the 20th century.
3.cardiovascular adj. [解剖] 心血管的
The major emphasis of this review will be CO and its effects on the cardiovascular system.
4.fluoride n. 氟化物
Fluoride damage is generally restricted to areas near manufacturing plants.
一项最近报道称近40亿人有严重蛀牙，该数字占到了世界人口的一半以上 。卫生官员警告说，不修复蛀牙会导致社会和情感问题 。
Wagner Marcenes就职于伦敦大学玛丽皇后学院牙科研究所，他领导的研究着团队参与了《2010年全球疾病负担研究》 。近500名研究者努力收集和调查有关重大疾病的研究 。
“龋齿是一种慢性病，和癌症、心脑血管病的风险差不多 。那些以前在发达国家高增长的疾病，如今也出现在撒哈拉南部非洲，可能还会出现在非洲其他地区 。”
西方饮食富含糖，糖是口腔卫生问题的主要原因 。西方国家用氟处理供应水，向水中添加氟能使牙齿能抵抗导致蛀牙的细菌 。
Wagner Marcenes说，口腔健康问题可能会对人的生活质量产生重大影响 。首先，蛀牙使得吃东西麻烦 。第二，人们只得改变饮食习惯，他们可能会吃容易咀嚼的软食 。不过，软食通常富含脂肪 。
但Marcenes教授说，蛀牙最大的问题是社会和心理方面 。他说，研究者发现强有力的证据，显示嘴巴会对社会化产生很大的影响 。他说很多人希望掩饰坏牙，这样就笑的少，社交也少了 。
Wagner Marcenes呼吁对普遍存在的口腔健康缺乏采取“紧急、有组织和社会化的反应” 。他推崇通过健康饮食这样的自然方法来与蛀牙做斗争，他还呼吁开发新型低廉的牙齿材料和疗法 。