1. Periodontics;Grant,1979
2. The association of posterior tooth irregularity and periodontal disease;Beagrie;Br Dent J,1962
3. The prevalence and possible role of non-working contacts in periodontal disease;Yuodelis;Periodontics,1965
4. The dynamic relationship between pathologically migrating teeth and inflammatory tissue in periodontal pockets: a clinical study;Hirshfeld;J Periodontol,1933
5. Glickman's clinical periodontology;Carranza,1979