Aim: The aim of this study was to compare the analgesic efficacy of two combinations of opioid and non-opioid analgesics for acute periradicular abscesses.

Methodology: This study included 24 patients who sought emergency care in a Brazilian dental school. The patients were randomly divided into two groups: Codeine/Acetaminophen - oral prescription of codeine (30 mg) plus acetaminophen (500 mg), every 4 h, for 3 days or Tramadol/Acetaminophen - oral prescription of tramadol hydrochloride (37.5 mg) plus acetaminophen (500 mg) on the same schedule. Patients recorded pain scores in a pain diary 6, 12, 24, 48, and 72 h after treatment, using the Visual Analogue Scale.

Inclusion Criteria:

• Clinical diagnosis of Acute Periradicular Abscess
• Age greater than 18 years
• Spontaneous pain greater than 40 mm measured in Visual Analogue Scale (moderate to severe pain).

Exclusion Criteria:

• Intake of analgesics or antibiotics within 4 hours prior to emergency surgery
• Allergy to the drugs used in this study
• Gastric ulcer, liver or kidney disease
• Uncontrolled diabetes mellitus or epilepsy
• Pregnancy or lactation