A pair of studies differed on the dental consequences of sports drinks.

A published study of more than 300 Ohio State University athletes showed no connection between the use of sports drinks and dental erosion. The level of dental erosion in athletes regularly using sports drinks was 36% versus 40% erosion in non-users.

The study, which was published in late 2002 in the journal Caries Research, disputes the idea that acidity in sports drinks contributes to dental erosion and contradicts the findings of a new study which appears in the January/February issue of General Dentistry.

"The results of the OSU study seem to disprove a misinformed belief," says Dr. Paul Casamassimo, one of the lead researchers for the Ohio State study. "The fact is, sports drinks are not by definition a cause of dental erosion."

The Ohio State study, the most comprehensive of its kind to-date, seemingly confirms previous scientific opinion that there is no link between sports drinks and dental erosion. Conducted in "real world" conditions with 304 male and female athletes, from a variety of ethnic backgrounds and high-intensity sports such as football and soccer, the study offers information not provided in past studies or in the other recently published study.

"This new study which attempts to link sports drinks to dental erosion has several limitations and should be taken with a grain of salt," said Casamassimo. "The primary limitation is that it does not replicate a real-world scenario. The teeth were studied outside of the mouth, so the study does not take into account the protective effect of saliva and the natural biological system."

"In contrast, the study conducted at OSU was conducted on real athletes and included more than 300 participants. It is the most comprehensive study of its kind to-date, and it hands-down demonstrated no link between sports drinks and dental erosion," he added.

Dental erosion is tooth wear that can occur for some people when acids interact with tooth enamel and, for as-yet-unexplained reasons, the enamel wears away. Causes of dental erosion include genetic factors, limited saliva production, acid reflux, a diet high in acidic foods or an eating disorder.

"It is also important to remember that dental erosion is usually caused by a variety of factors," added Casamassimo, a dentist at Children's Hospital in Columbus, Ohio. "Any attempt to link it to one food or beverage is misleading."

Tooth decay is different from dental erosion. Also called dental caries, tooth decay occurs as the result of acids produced by bacteria in the mouth. These bacteria use sugars for their acid production. However, practicing proper dental care -- regular brushing, flossing and dental visits -- is believed to be the best way to avoid dental caries.

The study published in General Dentistry found that these beverages may cause irreversible damage to dental enamel, potentially resulting in severe tooth decay.

"This study revealed that the enamel damage caused by non-cola and sports beverages was three to 11 times greater than cola-based drinks, with energy drinks and bottled lemonades causing the most harm to dental enamel," said J. Anthony von Fraunhofer, FRSC, FADM, lead author, professor of biomaterials science at the University of Maryland Dental School. "A previous study in the July/August issue of General Dentistry, the Academy of General Dentistry's (AGD) clinical, peer-reviewed journal, demonstrated that non-cola and canned iced teas can more aggressively harm dental enamel than cola."

The study continuously exposed enamel from cavity-free molars and premolars to a variety of popular sports beverages, including energy drinks, fitness water and sports drinks, as well as non-cola beverages such as lemonade and ice tea for a period of 14 days (336 hours). The exposure time was comparable to approximately 13 years of normal beverage consumption.

The study findings revealed that there was significant enamel damage associated with all beverages tested. Results, listed from greatest to least damage to dental enamel, include the following: lemonade, energy drinks, sports drinks, fitness water, ice tea and cola. Most cola-based drinks may contain one or more acids, commonly phosphoric and citric acids; however, sports beverages contain other additives and organic acids that can advance dental erosion. These organic acids are potentially very erosive to dental enamel because of their ability to break down calcium, which is needed to strengthen teeth and prevent gum disease.

"These findings are important and suggest that caution should be exercised when consuming popular sports beverages over long periods of time," said AGD spokesperson and president-elect Bruce DeGinder, DDS, MAGD. "We recommend altering or limiting the intake of soda and sports drinks and choosing water or low-fat milk instead, to preserve tooth enamel and ultimately protect teeth from decay."