These numbers reflect the depth of your gum. Along with the numbers mentioned with respect to pockets, there will be a correlated number referring to which tooth is affected. That way, it's easy for the attending dental hygienist to note where the problem pocket is located. The numbers you hear are the depths of the cavities around the teeth in millimeters.
Smaller, tighter pockets often mean healthier gums. We measure this distance in millimeters. As a patient, you'll want to hear a smaller number. This means that you have a smaller space between the tooth and the gum, a sign of a healthy mouth.
A higher or higher number indicates that you have gum problems, such as plaque and tartar buildup.