title: A further look at the role of radiographs in trials of caries-prophylactic agents.
abstract: To determine the role of bitewing radiographs in clinical trials of caries prophylactic procedures, data from the Chatham flossing study 26 were reanalyzed. The final examination records after 20 months of 147 second grade children were used to assess and compare the separate and combined results from clinical and radiographic examinations. Analysis of paired approximal surfaces from contralateral  test and control quadrants revealed that the addition of radiographic findings to clinical data changed the mean increment reduction from 22 to 26 percent. This slight increase was further supported by the results of similar studies which reported either separate or combined radiographic and clinical findings or both. Although the magnitude of the increase of the mean increment reduction remains uncertain, data from these studies indicate that the use of combined radiographic and clinical data might be justified when testing a particular prophylactic procedure which is expected to incur a significant caries reduction to approximal surfaces. Furthermore, findings suggest that clinical trials of certain prophylactic agents that are particularly beneficial to approximal surfaces, but which fail to include radiographic examinations, might actually underestimate the preventive effect of the agent.
mesh_terms: D002648:Child; D002986:Clinical Trials as Topic; D003731:Dental Caries / Q000000981:diagnostic imaging* / Q000517:prevention & control; D003742:Dental Devices, Home Care; D005069:Evaluation Studies as Topic; D005459:Fluorides / Q000627:therapeutic use; D006801:Humans; D009910:Oral Hygiene; D011859:Radiography; D012189:Retrospective Studies
chemical_list: D005459:Fluorides