Comparison of the Effects of Warfarin and Heparin on Bleeding Caused by Dental Extraction: A Clinical Study

Purpose: Replacement of warfarin with heparin for dental extractions in patients on long-term warfarin therapy is associated with wasted time, consumed labor, and increased treatment expenses. The aim of this study was to evaluate the safety of dental extraction without altering the warfarin regimen in patients with an international normalized ratio from 1 to 4. Patients and Methods: Forty patients who underwent tooth extraction were divided into 4 groups: continuation of warfarin without interruption (group 1), warfarin bridged with low-molecular-weight heparin (group 2), warfarin bridged with unfractionated heparin (group 3), and a control group of healthy individuals (group 4). Total amount of bleeding (milligrams) was measured for 20 minutes after tooth extraction. International normalized ratio values on the operative day and number of extra gauze swabs used for bleeding control in the first 48 hours were recorded for each patient. Results were statistically analyzed by analysis of variance, Fisher least-significant difference post hoc test, Pearson correlation, chi(2) test, and Student t test. Results: Mean amounts of bleeding were 2,486 +/- 1,408; 999 +/- 425; 1,288 +/- 982; and 1,736 +/- 876 mg for groups 1, 2, 3, and 4, respectively. There was no severe postoperative bleeding in any patient and the number of used extra gauze swabs did not differ significantly among groups. Conclusion: With the aid of local hemostatic agents, dental extraction in patients receiving warfarin who have an international normalized ratio from 1 to 4 could be carried out without a significant risk of bleeding and without altering the anticoagulant regimen. (C) 2011 American Association of Oral and Maxillofacial Surgeons J Oral Maxillofac Surg 69:2500-2507, 2011