“Brush your teeth after every meal.” We’ve heard that all our lives, but is that best for dental health?
We’ve gone through our lives hearing much advice on what to do and not to do, and what is good and bad for our teeth. Validating or debunking some of the common myths is Dr. Christopher Knight, DDS, Two Rivers Family Dental and Cosmetics, of Grangeville.
Myth: You must brush your teeth immediately after each meal.
No, said Knight, especially if you have had a menu item with high amounts of acid, such as lemon or lime, acidic drinks, Chinese candy, Mexican Lucas or Chimoy. These items cause immediate demineralization of enamel on contact, like an acid etch.
“If brushed immediately,” he said, “demineralized enamel will slough off like chalk,” which occurs at the microscopic level and can have a cumulative effect.
“Studies indicate and support that once you're done eating, don't brush your teeth immediately afterwards,” Knight said. “It sounds odd, but the abrasive materials in toothpaste can further damage tooth enamel weakened by acid.”
Instead, he recommends washing your mouth out with water, eating cheese or drinking milk to lower or neutralize the acid. Consuming dairy products after acidic foods or drinks also can reduce the possibility of dental erosion.
“In the meantime, wait at least an hour to brush,” he said, “and use a fluoride toothpaste to protect your teeth and reduce sensitivity."
Myth: Wisdom teeth serve no purpose.
“False,” said Knight, “They are like a spare gas tank...in reserve." His clinical opinion, he said, is based on 18 years of experience and reading several journals on the subject. Not all, but 90 percent of Homo sapiens develop third molars, and in most cases people function with them and without them.
“The problem is hygiene,” Knight clarified. “The back side of second molar is hard to keep clean if there is another tooth half-buried in the gum tissue behind it, which we do not use to chew with and collects huge amounts of food debris and plaque.” This harbors bacteria and causes infections known as pericoronitis (a swelling of gum tissue around tooth) and a cellulitis (or swelling) occurs.
Knight said, “95 percent of the time, it is prudent to extract them at 18-22 years of age, because younger peoples' bone is softer and less trauma is incurred on removal.” He said wisdom teeth can be used for bridge attachments and can be orthodontically moved forward to replace the second molar where actual mastication (or chewing) occurs.
“I have personally saved patients from having to wear partial dentures/ removable,” Knight said, “because that wisdom tooth is a good solid anchor for a bridge or implant-supported bridge.”
Another point: Wisdom teeth have no bearing on your front lower teeth getting crowded over time.
“Lower front tooth crowding is a natural aging occurrence without orthodontic intervention,” Knight said. “The lower front teeth are the smallest in the mouth. Gravity pulls down and forward in the dentition over time, and the entire dentition tends to move forward toward the smallest teeth; hence, lower crowding.
“This occurs in people born without wisdom teeth also,” he said, “hence, wisdom teeth do not cause anterior crowding.”
Myth: Toothpaste that contains fluoride is harmful and should be avoided
According to the American Academy of Pediatrics, 2017, fluoride is good for teeth, according to Knight.
“Fluoride is safe and effective at preventing decay,” he said. “There is no known scientific evidence that fluoride in small amounts causes any physical, mental or health disorders.”
The only proven issue with fluoride is in excess; it can cause faint white "streaks and/or spots" on the enamel called fluorosis, he said. Fluoride in toothpaste is in higher concentration than usually found in water, and parents with adolescent children must supervise brushing using the correct pea-size amount of paste.
“Fluoride strengthens the enamel on teeth, which combats the next round of acid attack from the bacteria, streptococcus mutans,” he said. “Fluoride is an important trace element/mineral for everyone, especially children.”