This book provides a concise account of the pathological processes involved in periodontal disease. The first chapter gives a broad overview of periodontal disease and is followed by accounts of the periodontum in health and disease. The book then deals with the micro-organisms implicated in periodontal disease and evaluates their significance. The host responses to factors present in dental plaque are discussed, and an account of the interactions between bacteria and the host which cause tissue damage is included. This leads to a consideration of the different clinical manifestations of the disease, including those associated with HIV infection. In the final chapter, a rational approach to treatment is presented, based on an understanding of the disease mechanisms discussed in the book. This volume will be valuable for dental students and dentists who wish to update their knowledge of this important subject.