Periodontal disease affects the gums and bone that support the teeth. To diagnose and manage it, dental professionals utilize a standardized classification system. This framework allows dentists and hygienists to communicate clearly about a patient’s condition and create a predictable and effective treatment plan.
The Spectrum of Gum Health
The condition of the gums exists on a spectrum, from health to disease. Healthy gums are firm, pale pink, and fit snugly around the teeth without bleeding during brushing or flossing. Maintaining this state requires consistent oral hygiene to manage the buildup of dental plaque.
Gingivitis represents the initial stage of gum disease and is characterized by inflammation. This condition is caused by plaque accumulation along the gumline, leading to redness, swelling, and bleeding. A characteristic of gingivitis is that it is reversible, as the inflammation is confined to the gum tissue and does not involve loss of the underlying bone.
When inflammation is left unaddressed, it can progress to periodontitis. This is an irreversible condition where inflammation extends below the gumline, causing destruction of the tissues and bone that support the teeth. Dental professionals diagnose these conditions by measuring the pocket between the tooth and gum with a periodontal probe. In periodontitis, these pockets become deeper as supporting structures are lost.
Staging Periodontitis
To define the severity of periodontitis, dental professionals use a system of staging. This method, updated at the 2017 World Workshop on the Classification of Periodontal and Peri-Implant Diseases and Conditions, classifies the extent and seriousness of the disease at the time of diagnosis. Staging provides a snapshot of how much tissue damage has occurred and helps determine the complexity of treatment. The system categorizes periodontitis into four distinct stages.
Stage I, or initial periodontitis, represents the earliest form of the disease. There has been a small amount of bone loss, and the pockets between the teeth and gums have started to deepen slightly. The clinical attachment loss (CAL), which is the measurement of tissue destruction, is minimal. The disease is manageable with non-surgical treatments like professional cleanings and improved home care.
Stage II signifies moderate periodontitis. The bone loss is more apparent on dental x-rays, and probing depths have increased further. The damage is more established, but the condition can still be controlled without surgical intervention. The primary goal of treatment is to halt the disease’s progression.
When the disease reaches Stage III, it is classified as severe periodontitis. There is significant loss of bone and tissue support, which can lead to loosening of the teeth. The pocket depths are considerable, often 6mm or greater, and there may be bone loss that has advanced vertically down the root of the tooth. Treatment is more complex and often requires surgical procedures to clean the deep pockets.
Stage IV represents the most advanced form of the disease. There is extensive bone loss, and many teeth may have already been lost or are in jeopardy. The condition significantly impacts the patient’s ability to chew. Managing Stage IV periodontitis is highly complex, often involving periodontal therapies and advanced restorative work like dental implants or dentures.
Grading the Progression of Disease
While staging defines the current severity of periodontitis, grading is used to estimate the future risk of disease progression. This part of the diagnosis addresses how quickly the disease is likely to advance if left untreated. Grading provides insight into the biological nature of the disease in an individual, helping to personalize the treatment approach.
The grading system is divided into three categories: A, B, and C. Grade A indicates a low rate of progression. This is assigned when there is evidence that bone loss has occurred slowly over a long period. A patient with Grade A periodontitis has a lower risk of future breakdown with appropriate care.
Grade B represents a moderate rate of progression and is the default rate for most individuals. Clinicians initially assume a patient has Grade B disease unless specific factors suggest a different progression. This grade implies that the rate of bone loss is consistent with the amount of plaque present.
A diagnosis of Grade C signifies rapid progression. This grade is assigned when tissue and bone destruction is advancing quickly, at a rate greater than expected based on the amount of plaque present. Risk factors that influence this are smoking and the level of glycemic control in patients with diabetes. A Grade C classification requires more intensive management.
Classifying Other Periodontal and Peri-Implant Conditions
The 2017 classification system is comprehensive, extending beyond periodontitis to other conditions affecting the supporting structures of the teeth. This framework allows for the classification of issues such as mucogingival deformities. These are conditions like gum recession, which exposes the root surfaces, or an inadequate amount of attached gum tissue.
As dental implants are a common solution for tooth replacement, the system also classifies the health and diseases related to them. Just as natural teeth have a periodontium, implants have peri-implant tissues. The classification defines peri-implant health, which is characterized by the absence of inflammation and bleeding when probed.
The system also identifies diseases that can affect implants. Peri-implant mucositis is the implant equivalent of gingivitis and is a reversible inflammatory condition confined to the soft tissues. If this progresses, it can lead to peri-implantitis, which is analogous to periodontitis and involves progressive loss of the bone supporting the implant.