Food particles can easily build up between the tooth and gums because of insufficient or improper brushing. This build up is called tartar or plaque.
The plaque harbors bacteria that are harmful to the gum tissue. The body will mount it’s defense against these bacteria.
The defense includes increased blood supply to the gums so the blood cells can counter the bacteria and its toxins. This increased blood supply to the gums manifests as bleeding of gums from brushing. This inflammation and bleeding gums are a manifestation of gingivitis.
If the bacterial assault continues the body might not be able to counter sufficiently. The toxins from the bacteria will then start destruction of the gum attachemnt and bone tissue under it. This is called loss of periodontal/gum tissue support. At this stage the disease has progressed in to periodontitis. The loss of gum attachment results in gum tissue pockets around teeth. These are safe havens for the bacteria to further colonize and proliferate. The deep pockets become inaccessible to regular brushing and, can accumulate more tartar and bacteria which can cause bad breath.
A deep cleaning/scaling root planing are recommended at this stage to remove tartar and diseased tissue from under the gums. An escalated cleaning regimen might be recommended to prevent build up. In certain cases a gum surgery might be recommended to clean inaccessible areas, graft bone tissue and to get rid of the deep gum pocketing.