Kansas City, Mo. ? The makers of Greenies, one of the nation’s best-selling dog treats, have settled a class-action lawsuit claiming the teeth-cleaning product injured or killed close to a dozen dogs.

U.S. District Judge Gary Fenner on Monday agreed with a joint request to dismiss the case.

Alan Sash, who represented 10 dog owners against Kansas City-based manufacturer S&M NuTec, said the case was settled but the terms were confidential.

An attorney for S&M NuTec, which was acquired last year by McLean, Va.-based candy conglomerate Mars Inc., also declined further comment.

Greenies are hard, dark green treats shaped like a bone on one end and a toothbrush on the other. Designed to scrub dogs’ teeth while being chewed, the treats have become extremely popular in recent years, with pet owners snapping up more than 300 million annually.

But beginning in 2005, media outlets began carrying stories of pet owners claiming their dogs either choked on pieces of Greenies or suffered medical problems when undigested pieces became trapped in their intestines.