Influence of Amoxicillin Dosage and Time of Administration on Postoperative Complications After Impacted Third Molar Surgery: A Randomized, Double-Blind, Controlled Clinical Trial

<b>Background/objective:</b> The objective of this research was to evaluate how different antibiotic prophylaxis protocols influence the development of postoperative complications after the extraction of impacted mandibular third molars. <b>Methods:</b> This investigation was designed as a double-blind, randomized controlled trial. A total of eighty patients who fulfilled the inclusion criteria were randomly allocated to one of three treatment groups. Group 1 (<i>n</i> = 27) was administered 2 g of oral amoxicillin one hour prior to the procedure; Group 2 (<i>n</i> = 27) received 500 mg of oral amoxicillin every eight hours for five days following the surgery; and Group 3 (<i>n</i> = 26) was given 750 mg of oral amoxicillin every eight hours for the same postoperative period. The outcome variables measured were infectious complications, postoperative pain, postoperative inflammation, and others such as the rescue medication taken by the patient. <b>Results:</b> Two patients in each group showed signs of infection after the extraction of the impacted third molar (<i>p</i> = 0.412). No significant differences were observed in pain intensity between the different study groups, nor in the intensity of inflammation. No statistically significant differences were observed in the consumption or non-consumption of rescue analgesics. <b>Conclusions:</b> The results of the present study suggest that the preoperative administration of 2 g of amoxicillin in the extraction of impacted third molars in healthy patients could be sufficient to prevent infectious complications. The administration of postoperative doses of 500 mg every 8 h or 750 mg every 8 h does not generate benefits in patients in terms of postoperative pain or inflammation.