This document discusses advances in periodontal diagnostic techniques. It begins by describing traditional diagnostic methods based on physical examination and signs/symptoms. It then explores developments in clinical diagnosis including methods to evaluate inflammation like gingival bleeding and crevicular fluid flow. The document also examines advances in imaging technologies and characterization of host response. Advances in probing devices are covered, moving from manual probes to computerized probes that provide precise, standardized measurements with controlled probing force.