A pocket is our dental name for the space that naturally exists between the gum and the tooth. Another name for a pocket is a sulcus. This is part of our normal anatomy. The gum does not attach to the tooth where our eyes tell us it does. Instead, it folds in and attaches lower on the tooth at a point that we cannot see. Thus, it forms a trough that goes all the way around the tooth.
Because this trough is an actual physical space, even though it is very narrow, we can measure its depth with a periodontal probe. This is a ruler that has millimeter markings on it. In health, the pocket is usually one to three millimeters deep. When periodontal infection is or was present, the space can measure four to ten millimeters and beyond.
So measuring pocket depths around the teeth is like measuring blood pressure, i.e., there are good readings and bad. Just like with blood pressure readings, we want these pocket depth readings to generally be as low as possible.
We all start with pocket depth readings of one to three millimeters. They generally become deeper due to only one cause – periodontal disease or infection in the gum that leads to bone loss around the teeth. Thus, if you have pocket depth readings over 3 millimeters, it means you are losing bone around your teeth. This is obviously not a good thing since we need to preserve the bone around the teeth if we want to keep them for a lifetime.
There are other reasons why deep pocket depth readings (over 3 millimeters) are a problem. It tells us that bacterial plaque is growing down the roots of the teeth and causing the destruction of the bone that supports the teeth and holds them in place. An equally big concern is that none of our homecare tools, i.e., toothbrush, floss, rinses, etc., reach below 3 millimeters. So, the harmful bacteria at the bottom of the deep pockets remain unaffected by our best efforts and continues to cause damage to the underlying bone.
In the same way, your dental professional can’t do a great job removing the plaque bacteria that you have missed when you come for your regular cleaning when the pockets are deeper than 3 millimeters, especially in the back of the mouth. Remember, when you come for a regular cleaning, you are expecting a comfortable visit in a relatively short period of time. For that to work, the spaces need to be shallow (1-3 millimeters).
So measuring pocket depths is something that should be done regularly, both by the periodontist and your general dentist. This is the only way to carefully and accurately measure the health of the gum and bone that supports your teeth.
If an examination shows that you have pocket depths deeper than 3 millimeters, then, depending on the depth, they can be managed in a number of ways ranging from careful monitoring, deep cleaning under local anesthetic, or surgery to reduce the size of the pocket.