The periodontal pocket, one of the definitive signs of periodontal disease, is the most common parameter to be assessed by dental clinicians. Periodontal probes have been the instruments most commonly used to locate and measure these pockets. Regular use of periodontal probes in routine dental practice facilitates and increases the accuracy of the process of diagnosing the condition, formulating the treatment, and predicting the outcome of therapy. Advances in the field of periodontal probing have led to the development of probes that may help reduce errors in determining this parameter used to define the state of active periodontal disease. One such advance is the emergence of probes that purportedly assess periodontal disease activity noninvasively. The selection of periodontal probe depends on the type of dental practice: a general dental practitioner would require first- or second-generation probes, while third- through fifth-generation probes generally are used in academic and research institutions as well as specialty practices.