Piercing is a hot fashion trend but you may not be smiling pretty for long if you get one in your mouth. A new study shows oral piercing -- such as on the tongue or lip -- may cause tooth loss.

'Wearing oral piercing ornaments, even over relatively short periods, may result in significant deformities to gingival tissue (gums) that might not respond satisfactorily to surgery and, in fact, may lead to tooth loss,' says lead researcher John K. Brooks, DDS, associate professor at the University of Maryland Dental School in a news release.

His study appears in the July issue of the Journal of the American Dental Association.

The damage to the gum line comes from the constant contact between the oral jewelry and the gums. The results can be permanent. They include:

Receding gums

Chipped or fractured teeth

Nerve damage or inflammation at piercing site

Periodontitis (when the inner layer of the gum and bone pull away from the teeth and form pockets) resulting in loose teeth or tooth loss

The researchers discussed five cases of young adults with oral piercing jewelry and the health of the gums near it. In each case, the patient had some degree of receding gums and injury near the piercing site. Three of them had signs of severe periodontitis.

In one case, a 19-year-old woman showed significant signs of receding gums in just five months. This type of fast-acting damage means it's critical for people with oral piercings to get regular dental checkups, Brooks says.

The article reports the most commonly pierced oral sites are the tongue and the lip. Tongue-piercing may damage gum tissue behind the lower front teeth, while lip-piercing may injure gum tissue in front of the lower teeth.