The guidelines on oral anticoagulation from the Haemostasis and Thrombosis Task Force for the British Committee for Standards in Haematology (1998) recommended that, after dental extractions, prevention of bleeding can be achieved with oral tranexamic acid mouth rinse (4·8%) without dose modification of oral anticoagulants. However, tranexamic acid does not have a product licence in the UK (Evans et al, 2001) and a letter from the North-west Medicines Information Centre to the Deans of UK dental schools clearly states that tranexamic acid mouth rinse should not be used in primary dental care (Randall, 2001).
To investigate whether warfarin can be continued during dental extractions, we performed a randomized controlled trial at Morriston Hospital in Swansea (Evans et al, 2002). The intervention group who continued on warfarin had a higher incidence of bleeding complications compared with the control group who stopped warfarin 2 days before extractions. However, this difference was not statistically significant. Furthermore, all but two patients controlled their minor post-operative bleeding by biting on gauze squares at home. In those two patients who attended hospital, the bleeding was stopped by local treatment of the extraction socket.
Our study supports the recommendations of the North-west Medicines Information Centre that warfarin does not need to be stopped before dental surgical procedures, providing the International Normalized Ratio of the patient is below 4. However, our study was performed in a hospital setting and it remains to be seen whether these findings can be translated to general dental practices.