Periodontal disease is a chronic inflammatory condition affecting the gums and the underlying structures supporting the teeth. Caused by a bacterial infection from plaque and tartar buildup, it leads to the progressive destruction of soft tissue and bone. This process is often silent, meaning a person may have the disease without pain. Understanding its progression across distinct stages is important for timely intervention and preventing irreversible damage.
Stage 1 The Reversible Phase (Gingivitis)
The initial phase is gingivitis, which occurs when bacterial plaque accumulates near the gum line. If this sticky film is not removed by regular brushing and flossing, it hardens into calculus (tartar), which provides a rougher surface for more bacteria. The body’s immune response causes inflammation limited entirely to the gum tissue.
This inflammation manifests as gums that appear red, swollen, or puffy, often bleeding easily. A dental professional confirms this stage by noting inflammation without any measurable loss of the connective tissue attachment. Because the underlying bone and ligaments remain undamaged, gingivitis is the only stage that is fully reversible with professional cleaning and consistent home hygiene.
Stage 2 Early Periodontitis (Initial Bone Loss)
If gingivitis is left untreated, the bacterial infection and inflammation extend deeper below the gum line, marking the transition to early periodontitis. This stage is defined by the start of irreversible attachment loss, where the fibers connecting the gum to the tooth root are destroyed. As the gum tissue detaches, shallow periodontal pockets begin to form, typically measuring 3 to 5 millimeters in depth.
These pockets create an environment where plaque and calculus accumulate further, sheltering destructive bacteria. The infection begins to erode the alveolar bone that anchors the tooth. While this initial bone loss, which may be up to 15% of the root length, is usually not visible, it can be confirmed through dental X-rays.
Stage 3 Moderate Periodontitis (Deepening Pockets)
The progression to moderate periodontitis involves an escalation of tissue destruction and bone loss. At this stage, periodontal pockets deepen significantly, often measuring 4 to 6 millimeters. This increased depth allows bacteria to colonize further down the tooth root surface, making the infection more difficult to manage with routine cleaning.
Bone loss becomes more pronounced, potentially reaching up to 30% of the tooth root support. Patients may start to notice symptoms such as gum recession, where the teeth appear longer, and slight tooth mobility. Treatment often involves a non-surgical deep cleaning procedure called scaling and root planing, which removes the calculus and infected tissue from the deepened pockets.
Stages 4 and 5 Severe Destruction and End-Stage Outcomes
Stages 4 and 5 represent the most advanced and destructive forms of the disease, often grouped as severe periodontitis, which compromises the teeth’s long-term survival. These stages are characterized by extensive bone loss, frequently exceeding 50% of the root support, and periodontal pockets that are 6 millimeters or deeper. The severe loss of supporting bone leads to significant tooth mobility, and teeth may visibly shift or fan out.
At this end-stage, the bacterial infection can lead to painful periodontal abscesses, and the stability of the bite can be compromised. Managing severe periodontitis often necessitates complex surgical interventions performed by a specialist. These procedures can include flap surgery, bone grafting, or guided tissue regeneration to attempt to rebuild lost supporting structures. The advanced destruction often results in a poor prognosis, leading to extractions to eliminate the chronic infection.