In most cases, potentially precancerous oral lesions caused by use of dip or chewing tobacco heal completely 6 weeks after quitting, researchers report.
'This finding was valid even for the subjects who had used smokeless tobacco for as long as 10 to 12 years and had severe lesions,' add researchers led by Lieutenant Colonel Gary Chad Martin, DDS, of the US Air Force Dental Corps. Their findings are published in the July issue of the Journal of the American Dental Association.
The popularity of 'dip' (tobacco placed between lip and gum) and 'chew' (chewed tobacco) has greatly increased over the past decade, especially among young white males. According to a 1997 US survey, one out of every five young male high school students reported using smokeless tobacco at least once within the past 30 days.
The researchers note that many teenagers turn to smokeless tobacco in the erroneous belief that it is a 'healthier alternative' to smoking cigarettes. However, numerous studies have linked chew and dip with cancers of the mouth and throat, which have a 5-year survival rate of just 50%. Over 30,000 new cases of mouth and throat cancer occur in the US each year, with 8,200 patients dying from the disease.
A large percentage of smokeless tobacco users develop leukoplakia -- oral lesions that are viewed by experts as potential precursors to cancer.
In their study, Martin's team examined whether these lesions would heal once users kicked the chew/dip habit. To do so, they followed the oral health of over 300 young US Air Force trainees who had used these products for an average of 3 years.
Nearly half of the chew/dip users (119) displayed evidence of leukoplakic lesions, according to the authors, with the severity of lesions increasing with rising levels of tobacco use and duration of habit.
'Men who use snuff (dip) are much more likely to have a leukoplakic lesion than are those who use chewing tobacco,' the authors add. Compared with nonusers, risks for oral lesions rose 48 and 3.4 times among dip and chew users, respectively.
However, the good news is that these lesions resolved completely in over 97% of cases when the men stopped chewing or dipping for just 6 weeks. 'Some lesions may resolve even more quickly,' the investigators add.
A number of leading health organizations, including the US Surgeon General's Office, the UN's World Health Organization, and the US National Institutes of Health, have concluded that long-term smokeless tobacco use raises risks for cancer. And last year the US National Toxicology Program took final steps toward adding smokeless tobacco products to its official list of carcinogens.
SOURCE: The Journal of the American Dental Association 1999;130:945-954.