Although the teeth may be perfectly formed and in good health, they may be lost because their supporting structures (gingivae and bone) are diseased. Periodontal disease is a chronic inflammatory disease which occurs most often in the middle age group, but its early beginnings may be detected in the form of early gingival trouble in children. The habits of modern man do not lead to periodontal health. Soft foods, inadequate hygiene, and the absence of chewing exercise all lead to soft, bleeding gums and poor bone support.
Gingivitis is an inflammation of the local gingival tissue surrounding the tooth. Poor hygiene is often the cause for gingivitis. Bacteria, chemical irritants from smoking, poorly fitting dental restorations, and improper contacts between teeth may also lead to inflammatory changes. Vitamin deficiencies may be factors favoring gingivitis.
If the inflammatory condition of the gingivae (gingivitis) is allowed to continue and advance without proper treatment, the underlying bone is affected and gradually destroyed. The resulting condition is called periodontitis.
One of the key clinical features of periodontitis is the presence of periodontal pockets. A periodontal pocket is a pathologically deepened gingival sulcus. Pocket formation is usually painless. The presence of periodontal pockets can be detected by use of a thin periodontal probe.
If causative factors are not eliminated, progressive proliferation and ulceration of epithelium results in a continued deepening of the pocket. Increased bone loss and destruction of the periodontal ligament cause the tooth to become mobile. Drifting of the teeth may serve to open contacts between the teeth.
Recession is a pathological condition in which the gingivae and underlying bore recede from the cementoenamel junction of the tooth. It may be caused by gingival inflammation from failure of the patient to remove bacterial plaque or by trauma from improper toothbrushing methods. The surgical treatment for pocket elimination in periodontal treatment may also produce areas of recession on teeth.
The exposed cement and dentin in areas of recession are sometimes sensitive to heat, cold, air, and acid-type foods. This condition is known as hypersensitive dentin or hypersensitive cement. The dentin of the tooth crown may also be exposed on the occlusal surface by wear or by caries and become hypersensitive to saliva, air, and sweet and sour foods.