A smile is a facial expression formed by flexing the muscles near both ends of the mouth. The smile can also be found around the eyes (see 'Duchenne Smiling' below). Among humans, it is an expression denoting pleasure, joy, happiness, or amusement, but can also be an involuntary expression of anxiety, in which case it is known as a grimace. Smiling is something that is understood by everyone despite culture, race, or religion; it is internationally known. Cross-cultural studies have shown that smiling is a means of communicating emotions throughout the world. But there are large differences between different cultures. A smile can also be spontaneous or artificial.
While most often, smiling is perceived as a positive emotion, there are many countries that perceive smiling as a negative expression and consider it unwelcoming. Too much smiling can be viewed as a sign of shallowness or dishonesty. The Japanese may smile when they are confused or angry. In other parts of Asia, people may smile when they are embarrassed. Some people may smile at others to indicate a friendly greeting. A smile may be reserved for close friends and family members. Many people in Russia consider smiling at strangers in public to be unusual and even suspicious behavior. Yet many Americans smile freely at strangers in public places (although this is less common in big cities). Some Russians believe that Americans smile in the wrong places; some Americans believe that Russians don't smile enough. In Southeast Asian cultures, a smile is frequently used to cover emotional pain or embarrassment. Vietnamese people may tell the sad story of how they had to leave their country but end the story with a smile.
What do people find most attractive in others? The smile. A national survey from the American Dental Association, Crest(R) and Oral B(R) finds that the smile outranked eyes, hair and the body as the most attractive physical feature.
Yet men and women differ when it comes to taking care of their teeth and gums. The nationally representative survey of 1,000 Americans ages 18 and older found 86 percent of women brush their teeth twice or more a day, yet only 66 percent of men do so.
The survey also found that women say they change their toothbrush or power
electric toothbrush head every 3-4 months on average, yet men hang on to theirs an average of 5 months. The ADA recommends replacing toothbrushes every 3-4 months or when the bristles become frayed since frayed and worn bristles decrease cleaning effectiveness.
Sadly, all Americans need to do a better job of flossing their teeth. Only half of those surveyed (49 percent) say they floss their teeth once a day or more often. And 1 out of 3 people surveyed think a little blood in the sink after brushing their teeth is normal, yet it's not -- it could signal gum disease or another health problem.
Oral health is an important part of overall health. Regular dental check-ups are important not only to diagnose and treat gum disease and tooth decay, but also because some diseases or medical conditions, such as oral cancer, have symptoms that can appear in the mouth.
Growing research indicates there may be an association between oral health and serious health conditions such as cardiovascular disease and diabetes, underscoring the importance of good oral hygiene habits.
