Radiological diagnostics serves as a basic monitoring technique for alveolar bone loss which is a severe consequence of periodontal disease. To evaluate efficacy of Conventional Visual Radiography (CVR), and to assess a complete clinical status, we had used two more diagnostic systems. These are Digital Subtraction Radiography (DSR) and Probing Pocket Depth (PPD). Experimental Periodontitis was studied in 20 beagle dogs based on the measurements taken in the beginning (baseline), and before (11th month) and after the medical treatment (12th month). Data analyses pointed out the same clinical trend, i.e. a significant bone loss prior to medical treatment and its recovery to the initial state. Differences in metrics and measurement errors could be identified as causes for discrepancies between the systems, but a relationship between the CVR and PPD is worth of further research, as these systems do not appear to be entirely compatible, but rather complementary to each other.