Plaque on its own is soft. Left alone for a few days, it hardens into tartar cement, a shell that locks onto the tooth and shelters the bacteria underneath. That's the smell you're noticing. Kelp enzymes in ProDenta penetrate that shell and break the calcium bonds holding it in place, one meal at a time. There's no scraping, no scrubbing, no fighting your dog for access to their mouth. You sprinkle it on, they eat like normal, and the breakdown happens on its own.