PERIODONTAL PROGNOSIS A comprehensive approach Various authors have recently been interested in shining light on the problem of scientific evidence-based periodontal prognosis. Dr.Pedro Martínez-Canut is one of the leading current exponents, and the manuel now in your hands is a contribution towards the development of modern periodontology. This book is the result of the enthusiasm that, throughout his professional life, the author has shown for unravelling the mysterries whereby some patients, and in them some teeth, resist the ravages of time and periodontal disease, yet others do not. After analysing an enormous amount of data over 25 years, his conclusions contribute towards a greater precision in establishing the prognosis of patients teeth, with a higher empirical than was available before now. The text introduces the LTOP system for assigning comprehensive periodontal prognosis by integrating overall prognosis and individual tooth prognosis. This approach is based on data gathered during moran than 25 years of research on periodontal prognosis and includes the following contributions: development of Perioproject, a prediction model of tooth loss due to periodontitis; development of the LTO index ( Long-term outcome index ) to identify, at baseline, the reduced percentage of patients with the highest risk of tooth loss, as well as identifying the two different profiles of patients ( Type 1 and Type 2 ) associated with bruxism and risk of losing more teeth; last but no least, development of the LTOP system to assign periodontal prognosis by integrating the LTO index and the estimated survival time assigned to periodontally involved teeth with Perioproject.