Haemostasis The haemostatic

methods for patients not receiving WF were chosen at the discretion of the dentist or oral surgeon performing the procedure. In patients on WF therapy, either absorbable oxidised cellulose or gelatin sponge was implanted into DAPT secretase Gamma-secretase inhibitor the alveolar socket, and wound margins were sutured. In both groups of patients, topical haemostatic agents other than epinephrine, systemic haemostatic agents and splints were prohibited until primary haemostasis was observed. In patients who had multiple teeth extracted in one session, possible postextraction bleeding was examined for each tooth. In a patient receiving WF, the postextraction procedure defined above was performed each time after a tooth was removed. Permitted drugs Use of local anaesthetics containing vasoconstrictors (eg, epinephrine and felypressin) was allowed at doses commonly given. In WF-treated patients, penicillins or cefems (eg, cefcapene pivoxil and cefditoren pivoxil) were the primary choice of prophylactic antibiotics for their minimal interaction with WF. For those who were allergic

to penicillins, clarithromycin was recommended. Use of analgaesics, such as acetaminophen, non-steroidal anti-inflammatory drugs and cyclo-oxygenase-2 inhibitors was allowed at ordinary doses. Confirmation of haemostasis All patients were asked to bite down on a roll of gauze for a maximum of 30 min for astriction of the wound. After release of the biting pressure, the wound was examined for haemostasis. Patients visited the hospital on the next day of surgery to check for possible bleeding, and were instructed to present at the hospital for treatment, if bleeding should occur later. The follow-up period was 7 days postoperatively. Follow-up of bleeding events If a patient had a bleeding event during the follow-up period, the severity of the haemorrhage and blood pressure were recorded. If the patient was on WF therapy, his or her PR-INR values were measured in addition. Evaluation of bleeding events In this study, bleeding events occurring in the follow-up period were classified into one of the following

5 grades: 0, no bleeding; 1, excessive blood clotting in the socket, no treatment required; 2-1, haemostasis achieved by compressing the wound longer than 30 min; 2-2, oozing haemorrhage observed on or after the next day of the procedure, in which haemostasis was achieved by simple Anacetrapib compression; 3, bleeding required treatments other than wound compression, such as application of compression brace and/or coagulation by electrotome was needed. Events of grade 2-2 and higher were regarded as clinically significant, and were defined as postextraction bleeds in this study. Statistical analysis Data were collected by a tooth, but not by a patient. This means that patients who had multiple teeth extraction were counted multiple times for the number of extracted teeth. Data were then sorted and analysed by the anatomical positions.