ABSTRACT
Aim: to evaluate the clinical efficacy of an acetaminophen analgesic by comparing its prescription in fixed versus ondemand schedules after periodontal surgery. The hypothesis of the study was that the fixed regimen would be more effective than the on-demand regimen for postoperative analgesics following periodontal surgery. Methods: An open randomized clinical trial was conducted. The 68 patients who needed total flap surgery to restore supracrestal tissue attachment or surgical treatment of periodontitis were randomized". Visual Analogue Scale was used to assess pain. The fixed group (n = 34) received 500 mg of acetaminophen every 4 hours for 2 days. The on-demand group (n = 34) was instructed to use the acetaminophen "as needed," at intervals of no less than 4 hours between doses. Ibuprofen was the rescue medication for both groups. Pain scores and medication use were recorded 2, 6, 12, 24 and 48 hours after the surgical procedure. The study was registered at the Brazilian Registry of Clinical Trials under RBR-7wv259. Results: The two groups did not differ in relation to the frequency or the intensity of pain in a 48-hour period (n=20 in the fixed group, and n=22 in the on-demand group), or even in the intention-to-treat (n=34 in each group). Individuals who experienced moderate to severe pain used rescue medication more frequently in both groups. No adverse events were reported. Conclusion: Both regimens were effective in controlling postoperative pain after periodontal surgery