A guide to common oral lesions

DESCRIPTION: Extension of gingival inflammation into the underlying bone and periodontal ligament is referred to as periodontitis. Since bone resorption is the outstanding feature, it is best seen on radiographs. Periodontitis is a silent disease with an occasional acute exacerbation in the form of local, painful abscesses. The gingiva is usually inflamed. The chief indicators of this disease are increased gingival sulcus depth as determined by gingival probing, and loss of alveolar bone as seen on radiographs. The conventional form of this disease starts in the teens or early adult years and without treatment shows gradual progression throughout life. It is the major cause of tooth loss in adults.

Three subtypes have been identified: (1) rapidly progressive periodontitis (RRP) affecting young adults; it resembles the conventional disease except that bone destruction is accelerated and occurs over a period of weeks or months rather than years; (2) juvenile periodontitis (JP) formerly known as periodontosis and typically affecting teenagers and characterized by destruction of alveolar bone around only first permanent molar teeth and incisor teeth; and, (3) prepubertal periodontitis (PP) affecting the deciduous teeth.

ETIOLOGY: Bacterial plaque is thought to be responsible for periodontitis. In the rapidly progressive type, there is evidence for increased activity of Bacteroides, Actinobacillus, Porphyromonas, and Prevotella organisms coupled with defects of leukocyte chemotaxis. In the juvenile (periodontosis) type, research has implicated a similar array of gram negative anaerobic rods as pathogens but there is no plausible explanation for the selective involvement of first molar and incisor teeth other than the “first erupted-first involved” theory. In the prepubertal form of periodontitis, genetically determined leukocyte adhesion molecule deficiency has been implicated. Disabling mutations in the gene for Cathepsin C account for the Papillon-Lefevre syndrome. From the above, it is obvious that alterations in plaque flora and reduced immunity are encountered in the subtypes of periodontitis.

TREATMENT: In conventional periodontitis, prevention is achieved through good dental hygiene. Unless treated, continued loss of alveolar bone eventually necessitates extraction of teeth. In those patients who still have adequate bone support, periodontal surgery to reduce the sulcus depth may be of benefit.

PROGNOSIS: The prognosis depends on the stage of the disease at the time treatment is instituted.