“Tooth loss and gum disease, which is inflammation (发炎) of the tissue around the teeth that can cause shrinkage (萎缩) of the gums and loosening of the teeth, are very common, so evaluating a potential link with brain diseases is incredibly important. Our study found that these conditions may play a role in the health of the brain area that controls thinking and memory, giving people another reason to take better care of their teeth,” said study author Satoshi Yamaguchi, Ph.D. of Tohoku University in Sendai, Japan.

The study involved 172 people with an average age of 67 who did not have memory problems at the beginning of the study. Researchers found that the number of teeth and amount of gum disease was linked to changes in the left hippocampus of the brain. For people with mild gum disease, having fewer teeth was associated with a faster rate of brain shrinkage, which was the same for people with severe gum disease having more teeth. After adjusting for age, researchers found that for people with mild gum disease, the increase in the rate of brain shrinkage due to one less tooth was equal to nearly one year of brain aging. By contrast, for people with severe gum disease, the increase in brain shrinkage due to one more tooth was equal to 1.3 years of brain aging.

“These results highlight the importance of preserving the health of the teeth and not just maintaining the teeth,” Yamaguchi said. Though the study does not prove that gum disease or tooth loss causes diseases like Alzheimer’s, it only shows an association. Yamaguchi added, “Future studies are needed with larger groups of people.” The current experiment involved only a small group of people in one region of Japan, and that too from one particular region of the world.

The Nose on Your Face

The human nose gives to the languages of the world many interesting expressions. Of course, this is not surprising. Without the nose, we could not breathe or smell. It is the part of the face that gives a person special character.

In English there are a number of phrases about the nose. For example, to hold up one’s nose expresses a basic human feeling -pride. People can hold up their noses at people, things and places.

The phrase, to be led around by the nose show man’s weakness. A person who is led around by the nose lets other people control him. On the other hand, a person who follows his nose lets his instinct (直觉、本能) guide him.

For the human emotion of rejection, the phrase to have one’s nose put out of joint(接头) is very descriptive. The expression is not new. It was Used by Erasmus in 1542.

This is only a sampling of expressions in English dealing with the nose. There are a number of others. However, it should be as plain as the nose on your face that the nose is more than an organ (器官) for breathing and smelling!

Many dentists are worried about their patients consuming too many sugar-filled sodas, sweet drinks and non-nutritious snacks. These foods don't have much nutritional value and they can take a toll on teeth.

What affect how quickly youngsters may develop tooth decay(蛀牙)are the eating habits and their food choices.With bacteria coming into contact with sugar in the mouth, acid( 酸)is produced. It will attack the teeth and eventually lead to tooth decay.

Foods containing sugar of any kind can lead to tooth decay. Almost all foods, even milk and vegetables, contain some type of sugar. Some of them, however, are a necessary part of a healthy diet due to their nutritional value. To help control the amount of sugar you consume, you need to read food labels carefully and choose foods and drinks with lower added sugar. Drinks, sweets and biscuits that contain a lot of added sugar shouldn't be on your shopping list.

Maintaining a diet lacking certain nutrients may increase the risk of tissue(4#A )infection in your mouth, which may result in a major cause of tooth loss in adults-the periodontal disease(2 a%P). Although poor nutrition and the periodontal disease are not directly related, many studies show that the disease progresses faster and can be more severe in people with nutrient-poor diets.

To make sure of enough nutrition, we need to maintain a balanced diet. Eating a variety of foods from each of the five major food groups and consuming less snacks will help a lot. If you do snack, choose nutritious foods, such as cheese, raw vegetables, plain yoghurt, or a piece of fruit.