Clear aligners are a common way to straighten teeth discreetly. Treatment involves wearing a series of clear, removable trays that gradually shift the teeth into a desired position. Gum recession is the loss of gum tissue around the teeth, which exposes the root surface and makes teeth appear longer. While aligners themselves are not typically the direct cause of recession, the combination of orthodontic force, pre-existing conditions, or patient habits can accelerate the problem.
The Mechanics of Aligner-Induced Tissue Change
Orthodontic treatment works by applying controlled pressure to move teeth through the jawbone. This force triggers a biological process where bone tissue is removed on one side of the tooth root and rebuilt on the other, allowing the tooth to shift. This movement is a delicate balance, and excessive force or speed can lead to recession if not carefully managed.
Recession can occur if a tooth is moved too far outward, beyond the supportive alveolar bone. When the root is pushed past the thin outer layer of bone, that bone can resorb, removing the underlying support for the gum tissue. This loss of bone leads to subsequent recession of the gumline.
A mechanical cause of recession relates to the aligner tray itself. If an aligner is poorly manufactured or inadequately trimmed, its edge may rub against the gingival margin. This constant irritation and pressure can cause localized inflammation and trauma, leading the gum tissue to pull away from the tooth surface. A proper fit of the clear tray is important for protecting the gum tissue during treatment.
Primary Patient Factors That Increase Recession Risk
While mechanics play a role, recession often results from pre-existing patient factors and habits. One significant factor is the patient’s natural gum tissue thickness, known as the gingival biotype. Patients with a thin biotype are more susceptible to recession because their tissue is fragile and prone to breakdown during orthodontic movement or inflammation.
Pre-existing periodontal disease is another accelerator of recession. If a patient has active gum disease, tissues are already inflamed and compromised. The combination of bacterial infection and orthodontic force can lead to rapid bone loss and subsequent gum recession. Therefore, a periodontal screening is recommended before starting tooth movement.
Poor oral hygiene practices are common indirect causes of recession while wearing aligners. Aligners trap food particles and plaque against the teeth and gums, creating an ideal environment for bacterial growth. If the teeth and aligners are not meticulously cleaned, plaque accumulation causes gingivitis. This inflammation, combined with the pressure of tooth movement, can accelerate gum recession.
Aggressive brushing technique is also a factor, often worsening existing issues. Brushing too hard, especially with a hard-bristled toothbrush, physically wears away the gum tissue over time. When aligners are worn, the gum tissue may be slightly more vulnerable. The trauma from aggressive brushing can accelerate recession, unmasking or worsening a problem already present.
Recognizing and Managing Gum Recession
Recognizing the early signs of gum recession is important for timely intervention. The most common visual indicator is that the teeth begin to appear longer than usual, as more of the tooth surface becomes visible. Patients may also notice a change in the gumline, which may look visibly shrunken or pulled back.
A frequent symptom accompanying recession is increased tooth sensitivity, particularly when consuming hot, cold, or sweet foods and drinks. This sensitivity occurs because the protective enamel ends at the gumline. The newly exposed root surface underneath is much more vulnerable. Any persistent gum discomfort, soreness, or bleeding during routine brushing should be reported immediately to the dental provider.
If recession is noticed, the first step involves determining the exact cause, requiring an assessment of brushing technique and aligner fit. Patients should switch to a soft-bristled toothbrush and use a gentle, circular motion to clean the teeth and gums. Meticulous cleaning of the aligners is equally important to minimize bacterial buildup. The orthodontist may need to temporarily pause tooth movement, adjust the treatment plan, or modify the aligner trays to reduce pressure.