Educational Practices Regarding Anticoagulation and Dental ...

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Educational Practices Regarding Anticoagulation and Dental Procedures in U.S. Dental Schools Sunny A. Linnebur, Pharm.D.; Samuel L. Ellis, Pharm.D.; Jeffrey D. Astroth, D.D.S., M.S.P.H. Abstract: Evidence suggests that stopping oral anticoagulation with warfarin is not necessary in patients requiring low-risk dental procedures and may actually increase thrombosis risk. However, widespread belief remains among dentists that stopping oral anticoagulation for dental procedures is necessary. The purpose of this study was to investigate the teaching practice of U.S. dental faculty responsible for providing education to dental students about anticoagulation. Surveys were mailed in 2003 and 2004 to fifty-five U.S. dental faculties to assess their teaching practice regarding anticoagulation and dental procedures. Twenty-eight (50.9 percent) of the schools returned surveys. Contrary to evidence indicating anticoagulation does not need to be altered, many dental faculty responded that they teach dental students to discuss with medical providers/patients about altering warfarin therapy for several routine procedures: 21.4 percent (cleaning), 14.3 percent (restorative treatment), 46.4 percent (single simple extraction), 64.3 percent (multiple simple extractions), and 17.9 percent (root canal). However, 67.9 percent stated an International Normalized Ratio (INR) of 2.0-3.0 would be acceptable prior to dental procedures. A discrepancy was also found between the number of faculty recommending altering warfarin in intermediate- to high-risk individuals compared to those recommending heparin bridging for the same patients. Overall, this study identified inconsistencies between teaching practices in U.S. dental schools and medical evidence. Dental faculty should consider comparing their teaching material with evidence regarding anticoagulation and dental procedures. Continuing education may be necessary for practicing dentists regarding this topic. Dr. Linnebur is Assistant Professor, Department of Clinical Pharmacy; Dr. Ellis is Assistant Professor, Department of Clinical Pharmacy; and Dr. Astroth is Associate Professor, Department of Applied Dentistry—all at the University of Colorado at Denver and Health Sciences Center. Direct correspondence and requests for reprints to Dr. Sunny A. Linnebur, Department of Clinical Pharmacy, University of Colorado at Denver and Health Sciences Center, 4200 E. Ninth Ave., Campus Box C238, Denver, CO 80262; 303-315-1561 phone; 303-315-4630 fax; [email protected]. This research was supported by an investigator-initiated clinical research grant from Bristol-Myers Squibb. Key words: dentistry, dentists, education, school dentistry, dental education, dental continuing education, anticoagulants, hemorrhage Submitted for publication 7/6/06; accepted 9/21/06

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ral anticoagulation with warfarin is widely prescribed for various medical conditions. Many patients, such as those with atrial fibrillation, multiple venous thromboembolisms, and artificial heart valves, are recommended to continue warfarin therapy indefinitely. Consequently, dental procedures in patients who are taking warfarin are common. Some controversy regarding continuing or discontinuing anticoagulation therapy prior to dental procedures existed in the 1980s and 1990s. However, a plethora of data1-11 and expert opinions12-20 now exist to support that patients with therapeutic levels of warfarin can continue their therapy through routine dental procedures without major bleeding complications. Moreover, anticoagulation guidelines 21,22 recommend that warfarin be continued through most dental procedures. Unfortunately, there is still a

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general belief among practicing dentists that anticoagulation must be stopped prior to dental procedures to prevent bleeding.12,23,24 This belief and practice potentially put anticoagulated patients at an unnecessary risk of thromboembolic events.16 In fact, in 1998 Wahl found that five serious thromboembolic events (including four deaths) had been reported in patients who stopped anticoagulation for dental procedures.16 At this time, it is unknown if the practice of stopping warfarin therapy prior to dental procedures is due to pressure from physicians and other providers to discontinue anticoagulation before dental procedures or due to a lack of understanding among dentists as a result of inadequate continuing education or deficiencies in dental training. Thus, the purpose of this study was to determine the characteristics of U.S. dental school teaching practices regarding anticoagulation management during dental procedures.

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Methods The study was approved by the Colorado Multiple Institutional Review Board in September 2003. Fifty-five U.S. dental schools were surveyed in November 2003 regarding teaching practices related to anticoagulation and dental procedures. Surveys were mailed to the faculty member(s) at each institution identified as responsible for teaching in this area. A follow-up survey was mailed in February 2004 to schools that had not yet responded. The survey collected both demographic information and information regarding teaching practices. Demographic information collected included dental school name, primary field of practice, practice setting, hours per week spent in direct patient care, and years of teaching the topic of anticoagulation and dentistry. The survey consisted of seven questions designed to collect information regarding teaching practices related to anticoagulation and dental procedures (Figure 1). Several of the survey questions were based on a previously published anticoagulation/dental survey.25 Survey responses were received by regular mail, fax, or email. Descriptive statistics (percent) were performed for demographic information and survey responses. An analysis based on years spent teaching anticoagulation (fifteen years or less compared to greater than fifteen years) was also completed using Microsoft Excel 2003 (Redmond, WA).

Results Of the fifty-five surveys mailed to U.S. dental schools, twenty-eight (50.9 percent) were returned, representing most geographic areas of the United States. Table 1 describes the characteristics of the survey respondents. The majority of the faculty members completing the survey were associated with a Department of Oral and Maxillofacial Surgery and indicated they were full-time faculty. Slightly over 40 percent of the respondents indicated they spend greater than thirty hours per week providing direct patient care, while 18 percent indicated they provide patient care for ten or fewer hours per week. Of the faculty responding, many stated they have been teaching the topic of anticoagulation and dentistry for longer than fifteen years. Only two respondents stated they have been teaching the topic for two years or less.

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Table 1. Characteristics of survey respondents* Academic department Oral and Maxillofacial Surgery General Dentistry Oral Medicine

24 (85.7) 2 (7.1) 2 (7.1)

Primary practice setting+ Full-time academic Part-time academic Private practice Community Other

23 (82.1) 4 (14.3) 2 (7.1) 1 (3.6) 4 (14.3)

Time spent in patient care (hours) Less than 5 6-10 11-20 21-30 Greater than 30

2 3 5 6 12

(7.1) (10.7) (17.9) (21.4) (42.9)

Time spent teaching anticoagulation (years) 1-2 2 3-5 6 6-10 3 11-15 4 Greater than 15 13

(7.1) (21.4) (10.7) (14.3) (46.5)

*Survey responses are presented as N (%) out of a total of 28 responses. + Respondents could indicate more than one practice area, so the total percentage is greater than 100 percent.

Table 2 provides a summary of responses to the survey questions regarding teaching practices and anticoagulation. A few surveys did not include responses to all questions or they included text in their responses, so these responses could not be utilized. Percentage response was calculated from a total of twenty-eight responses. In the analysis based on time spent teaching anticoagulation, no responses were statistically different between groups. However, in general, more faculty who reported teaching for greater than fifteen years responded that they do not teach students to recommend holding warfarin for low-risk dental procedures (e.g., professional cleaning, restorative treatment, simple extractions, and root canal) or with high-risk indications (e.g., artificial valve replacement, systemic emboli, history of stroke/transient ischemic attack). On the other hand, more faculty who reported teaching for fifteen years or less responded that they teach students to recommend heparin or low-molecular weight heparin (LMWH) for the same high-risk indications and also responded that

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Anticoagulation Survey 1.

For the following dental procedures, do you teach dental students to discuss the need to change warfarin (Coumadin®) therapy to lower the INR value and/or prevent bleeding? (Please circle one answer for EACH procedure.) a. Professional cleaning Yes No b. Restorative treatment Yes No c. Simple extraction: single Yes No d. Simple extraction: multiple Yes No e. Deep periodontal scaling Yes No f. Gingival periodontal surgery Yes No g. Surgical extraction and alveolar surgery Yes No h. Conventional root canal therapy Yes No

2.

If you circled “Yes” to any answer above, which INR range do you teach that the patient’s INR value be in prior to that dental procedure? If you circled “Yes” multiple times, please choose the most general answer. (Please circle one answer.) a. 1.0 c. 1.5-1.9 e. 3.1-4.0 b. 4.0

3.

For the following medical conditions, do you teach dental students to discuss the need to change warfarin therapy prior to performing dental procedures in a patient with the specified medical condition? (Please circle one answer for EACH condition.) a. Atrial fibrillation without stroke or TIA history Yes No b. Artificial heart valve Yes No c. Valvular heart disease Yes No d. Left ventricular dysfunction or thrombosis Yes No e. History of systemic embolism Yes No f. History of transient ischemic attack or stroke Yes No

4.

When teaching dental students to discuss changing warfarin therapy prior to any procedure, how do you recommend changing it? (Please circle one answer.) a. I do not recommend changing it d. Hold 5-7 days warfarin prior to procedure b. Hold 1-2 days warfarin prior to procedure e. Hold >7 days warfarin prior to procedure c. Hold 3-4 days warfarin prior to procedure f. Reduce warfarin dose prior to procedure

5.

When recommending a change in warfarin therapy prior to a dental procedure, for each medical condition below do you teach that it is necessary to use a bridge of heparin or low-molecular weight heparin in place of warfarin to prevent thromboembolism? (Please circle one answer for EACH condition.) a. Atrial fibrillation without stroke or TIA history Yes No b. Artificial heart valve Yes No c. Valvular heart disease Yes No d. Left ventricular dysfunction or thrombosis Yes No e. History of systemic embolism Yes No f. History of transient ischemic attack or stroke Yes No g. Bridge with for all medical conditions Yes No h. I do not recommend changing warfarin Yes No

6.

What is the primary resource you use to teach your lecture(s) about dental procedures and anticoagulation? (Please circle one answer.) a. Clinical experience d. CHEST supplement g. Discussions with colleagues b. Your lecture notes e. Medical literature h. Other __________________ c. JADA recommendations f. Continuing education

7.

When you teach anticoagulation and dental procedures, which clinician do you state should be MOST responsible for managing warfarin therapy? (Please circle one answer.) a. Dentist d. Nurse b. Physician/Primary care provider e. Other _________________ c. Pharmacist

Figure 1. Survey instrument

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Table 2. Responses to survey questions* Question 1. Respondents stating they teach dental students to discuss changing warfarin therapy for the following procedures

Professional cleaning Restorative treatment Simple single extraction Simple multiple extraction Deep periodontal scaling Gingival periodontal surgery Surgical extraction and alveolar surgery Conventional root canal therapy

6 4 13 18 12 15 21 5

(21.4) (14.3) (46.4) (64.3) (42.9) (53.6) (75.0) (17.9)

Question 2. International normalized ratio (INR) range taught to achieve prior to dental procedures INR 1.0 0 (0.0) INR 4.0 0 (0.0) Question 3. Respondents stating they teach dental students to discuss changing warfarin therapy for the following medical conditions Atrial fibrillation without stroke or transient ischemic attack history 12 (42.9) Artificial heart valve 16 (57.1) Valvular heart disease 14 (50.0) Left ventricular dysfunction or thrombosis 16 (57.1) History of systemic embolism 14 (50.0) History of transient ischemic attack or stroke 14 (50.0) Question 4. Recommendations taught to dental students regarding how to change warfarin therapy prior to a procedure Changing warfarin not recommended 8 (28.6) Hold 1-2 days of warfarin 6 (21.4) Hold 3-4 days of warfarin 10 (35.7) Hold 5-7 days of warfarin 0 (0.0) Hold >7 days of warfarin 0 (0.0) Reduce warfarin dose 1 (3.6) Question 5. Respondents stating they teach dental students to also recommend bridging with heparin or low-molecular weight heparin when recommending a change in warfarin therapy for the following medical conditions Changing warfarin not recommended 6 (21.4) Bridge for all medical conditions 1 (3.6) Atrial fibrillation without stroke or transient ischemic attack history 1 (3.6) Artificial heart valve 6 (21.4) Valvular heart disease 3 (10.7) Left ventricular dysfunction or thrombosis 5 (17.9) History of systemic embolism 4 (14.3) History of transient ischemic attack or stroke 3 (10.7) Question 6. Primary resource used to teach lecture(s) about dental procedures and anticoagulation+ Clinical experience 8 (28.6) Lecture notes 2 (7.1) JADA recommendations 4 (14.3) CHEST supplement 1 (3.6) Medical literature 13 (46.4) Continuing education 2 (7.1) Discussions with colleagues 2 (7.1) Other 1 (3.6) Question 7. Clinician most responsible for managing warfarin therapy Dentist Physician Pharmacist Nurse Other

4 21 1 0 2

(14.3) (75.0) (3.6) (0.0) (7.1)

*Survey responses are presented as N (%) out of a total of 28 responses. + Some respondents indicated more than one resource so the total percentage is greater than 100 percent.

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they utilize Journal of the American Dental Association (JADA) or CHEST (American College of Chest Physicians) guidelines as the primary resource for teaching anticoagulation.

Discussion Overall, many dental faculty responded that they teach dental students to discuss with medical providers/patients about changing warfarin for a variety of dental procedures. Some of these procedures, such as professional cleanings, restorative treatment, single simple extractions, multiple simple extractions, and conventional endodontic therapy, are considered to be low-risk procedures that should not require anticoagulation alteration prior to the procedure.12-20 Multiple studies have shown that dental extractions (both single and multiple) can be performed with International Normalized Ratios (INRs) ranging from 2.0 to 4.0 without major bleeding complications.1-11 Current anticoagulation guidelines recommend INR goals within this range: 2.0-3.0 for most patients taking warfarin and possibly higher ranges up to 3.5 or 4.0 for patients with mechanical heart valves, acute myocardial infarction, or antiphospholipid syndrome.21 Evidence supports that alteration of warfarin therapy is not necessary for low-risk dental procedures. Zanon et al. prospectively studied dental extractions and bleeding in 250 patients stabilized on warfarin and 250 non-anticoagulated patients (control group).10 Single or multiple extractions of varying degrees of complexity were performed, with a total of 525 extractions in the anticoagulated patients and 513 extractions in the control group. After extraction, a piece of oxidized cellulose was inserted into the wound, and a silk suture was applied in all anticoagulated patients and in most of the control patients. Gauze saturated with tranexamic acid was also kept in place for thirty to sixty minutes in the anticoagulated patients. Bleeding and other complications were evaluated on the third and eighth days following the procedure. The number of bleeding complications in the anticoagulated patients (n=4) was not significantly different from the number in the control patients (n=3), p=0.7. No significant differences in bleeding were seen based on different INR values: 1.2 percent with INR 1.8-2.0; 1.3 percent with INR 2.0-3.0; and 4.8 percent with INR 3.0-4.0. No patients required alteration of anticoagulant therapy, hospitalization, or transfusion. This

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and other studies support that patients can continue their anticoagulation therapy during both single and multiple extractions when simple local measures are instituted. However, we found in our study that 46.4 percent and 64.3 percent of faculty stated they teach dental students to discuss with medical providers/patients altering warfarin for simple single and multiple extractions, respectively. In another study by Blinder et al., 249 anticoagulated patients had 543 simple single and multiple dental extractions without interruption of their warfarin therapy.7 All patients received local hemostatic measures of gelatin sponges and silk sutures. INRs were measured on the day of the extraction. For results purposes, patients were divided into groups based on their INR values: 1.5-1.99, 2-2.49, 2.52.99, 3-3.49, and >3.5. Overall thirty (12 percent) patients presented with minor postoperative bleeding. Although slightly less bleeding (5 percent) occurred in the group with the lowest INR range compared to the other groups (range 12.8 percent to 16.6 percent), the incidence of bleeding was not significantly different between groups. In addition, the INR value did not significantly affect the incidence of bleeding. In those patients with minor postoperative bleeding, additional curettage, gelatin sponges, sutures, or gauze soaked in tranexamic acid provided hemostasis. These data indicate that the INR range prior to extraction does not significantly affect bleeding rates in anticoagulated patients when local hemostatic measures are employed. In our survey, 67.9 percent of dental faculty responded that they teach students to achieve an INR within 2.0 to 3.0, which is the therapeutic range for most anticoagulated patients. However, 17.9 percent of dental faculty responded that they teach students that INRs should be in the range of 1.5-1.9 prior to dental procedures. Many dentists may fear that local measures are not effective at controlling bleeding in anticoagulated patients. However, numerous studies indicate that tranexamic acid-soaked gauze, tranexamic acid mouthwash, histoacryl glue, fibrin glue, gelatin sponges, and plasma gel are effective.8-10,26-32 Blinder et al. compared three local measures to stop bleeding in anticoagulated patients undergoing dental extractions.26 A total of 150 patients who had 359 extractions were treated with either 1) gelatin sponge and silk sutures; 2) gelatin sponge, silk sutures, and 500mg tranexamic acid mouthwash (repeated four times daily for four days); or 3) gelatin sponge, silk sutures, and fibrin glue. In total, thirteen (8.6 percent) of the patients presented with postoperative bleed-

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ing: three patients from group 1, four patients from group 2, and six patients from group 3. A comparison of the bleeding rates between the groups indicated no significant differences. Local measures were effective at stopping bleeding in all patients, as none required acrylic splint or systemic treatment. Thus, standard and additional local measures are effective for hemostasis in anticoagulated patients undergoing dental extractions. In our survey we also assessed teaching practices concerning indications for warfarin and their effect on anticoagulation management around dental procedures. Interestingly, one-half of faculty indicated they teach students to consider altering warfarin around moderate- to high-risk conditions, such as in patients with an artificial heart valve, history of systemic embolism, and history of transient ischemic attack or stroke. However, only a low number of faculty (21.4 percent, artificial heart valves; 14.3 percent, history of systemic embolism; and 10.7 percent, history of transient ischemic attack or stroke) indicated they teach dental students about bridging with heparin or LMWH when changing warfarin in moderate- to highrisk patients. This disparity in teaching is concerning, as altering warfarin therapy in high-risk individuals without bridging with heparin or LMWH could place the patient at high risk of thrombosis. Anticoagulation guidelines suggest that, in patients at intermediate to high risk of thrombosis, heparin or LMWH should be utilized when holding warfarin therapy for procedures.21 This practice minimizes the time the patient is not adequately anticoagulated from approximately one week (when holding warfarin) to less than one day (when bridging with heparin or LMWH). Although heparin bridging is primarily the responsibility of the primary care provider, many patients may not let their physicians know about the procedure and may proceed through the dental work without adequate protection for thrombosis. Thus, practicing dentists should be aware that stopping warfarin prior to dental procedures in some patients necessitates additional anticoagulation coverage with a heparin product. In addition, weighing the risk of bleeding versus thrombosis is extremely important as heparin and LMWH can be costly, time-consuming, and difficult for some patients to manage. Thus, avoiding the need for heparin products by continuing warfarin therapy through dental procedures is less complicated in general than stopping warfarin. Since many studies and review articles are available on the topic of anticoagulation and dental

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procedures, it is not surprising that we found 64.3 percent of dental faculty utilize medical literature, recommendations from JADA, or recommendations from CHEST as the primary resource for their lectures on the topic. However, 28.6 percent of faculty stated they rely on clinical experience rather than evidence-based medicine to teach on this topic. It is possible that those unfamiliar with anticoagulation data and guidelines are the faculty teaching students that holding warfarin for low-risk dental procedures is appropriate. In our analysis based on years spent teaching anticoagulation, those with a shorter teaching history indicated they utilize recommendations from JADA and CHEST in their teaching more so than those with a longer teaching history. This is a positive finding; however, it did not translate into the junior faculty teaching to alter warfarin less often for low-risk dental procedures. Our survey results also indicate that the majority of dental faculty stated the physician is the primary clinician responsible for managing warfarin therapy. Thus, physicians also need to be educated with data and guidelines pertaining to dental procedures in anticoagulated patients. This study has several limitations. First, the results relied upon survey responses, which were only received by approximately one-half of dental schools in the United States. In addition, some surveys were only partially completed or had text instead of a marked reply, so the replies could not be counted. Next, the survey was mailed in late 2003 and early 2004, so the faculty may have already updated their teaching practices in subsequent years to reflect more current guidelines and data. Finally, the survey was limited to questions regarding warfarin and did not include questions about other antiplatelet agents like aspirin or clopidogrel. It is possible that some respondents may have responded differently to the survey if they were asked about both warfarin and antiplatelet agents. However, evidence also supports that antiplatelet agents do not need to be stopped prior to dental procedures.12,33

Conclusions Inconsistencies were found between teaching practices in U.S. dental schools and medical evidence regarding 1) changing warfarin therapy prior to lowrisk dental procedures and 2) heparin bridging for intermediate- to high-risk patients. Dentists should be aware that changing warfarin therapy prior to routine, low-risk dental procedures, including simple

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single and multiple extractions, is not necessary and that local measures are effective at controlling bleeding. Dental faculty should consider comparing their teaching material with available evidence on this topic and updating their material if necessary. Continuing education in the area of anticoagulation may also be warranted for practicing dentists.

Acknowledgments

The authors would like to acknowledge the assistance of Michele Ensign, dental hygienist, for her help with data collection and analysis.

REFERENCES 1. Evans IL, Sayers MS, Gibbons AJ, Price G, Snooks H, Sugar AW. Can warfarin be continued during dental extraction? Results of a randomized controlled trial. Br J Oral Maxillofac Surg 2002;40(3):248-52. 2. Campbell JH, Alvarado F, Murray RA. Anticoagulation and minor oral surgery: should the anticoagulation regimen be altered? J Oral Maxillofac Surg 2000;58(2):131-5. 3. Devani P, Lavery KM, Howell CJT. Dental extractions in patients on warfarin: is alteration of anticoagulant regime necessary? Br J Oral Maxillofac Surg 1998;36(2):107-11. 4. Bailey BMW, Fordyce AM. Complications of dental extractions in patients receiving warfarin anticoagulant therapy: a controlled clinical trial. Br Dent J 1983;155(9):308-10. 5. Al-Mubarak S, Rass MA, Alsuwyed A, Alabdulaaly A, Ciancio S. Thromboembolic risk and bleeding in patients maintaining or stopping oral anticoagulant therapy during dental extraction [letter]. J Thromb Haemost 2006;4(3):68991. 6. Sacco R, Sacco M, Carpenedo M, Moia M. Oral surgery in patients on oral anticoagulant therapy: a randomized comparison of different INR targets [letter]. J Thromb Haemost 2006;4(3):688-9. 7. Blinder D, Manor Y, Martinowitz U, Taicher S. Dental extractions in patients maintained on oral anticoagulant therapy: comparison of INR value with occurrence of postoperative bleeding. Int J Oral Maxillofac Surg 2001;30(6):518-21. 8. Vicente Barrero M, Knezevic M, Tapia Martin M, Viejo Llorente A, Orengo Valverde JC, Garcia Jimenez F, et al. Oral surgery in patients undergoing oral anticoagulant therapy. Med Oral 2002;7(1):63-70. 9. Souto JC, Oliver A, Zuazu-Jausoro I, Vives A, Fontcuberta J. Oral surgery in anticoagulated patients without reducing the dose of oral anticoagulant: a prospective randomized study. J Oral Maxillofac Surg 1996;54(1):27-32. 10. Zanon E, Martinelli F, Bacci C, Cordioli GP, Girolami A. Safety of dental extraction among consecutive patients on oral anticoagulant treatment managed using a specific dental management protocol. Blood Coagul Fibrinolysis 2003;14(1):27-30. 11. Cannon PD, Dharmar VT. Minor oral surgical procedures in patients on oral anticoagulants: a controlled study. Aust Dent J 2003;48(2):115-8.

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12. Jeske AH, Suchko GD. Lack of a scientific basis for routine discontinuation of oral anticoagulation therapy before dental treatment. J Am Dent Assoc 2003;134(11):1492-7. 13. Wahl MJ. Myths of dental surgery in patients receiving anticoagulant therapy. J Am Dent Assoc 2000;131(1): 77-81. 14. Herman WW, Konzelman JL, Sutley SH. Current perspectives on dental patients receiving coumarin anticoagulant therapy. J Am Dent Assoc 1997;128(3):327-35. 15. Weibert RT. Oral anticoagulant therapy in patients undergoing dental surgery. Clin Pharmacol 1992;11(10): 857-64. 16. Wahl MJ. Dental surgery in anticoagulated patients. Arch Intern Med 1998;158(15):1610-6. 17. Scully C, Wolff A. Oral surgery in patients on anticoagulant therapy. Oral Surg Oral Med Oral Pathol Oral Radiol Endod 2002;94(1):57-64. 18. Muzyka BC. Atrial fibrillation and its relationship to dental care. J Am Dent Assoc 1999;130(7):1080-5. 19. Carter G, Goss AN, Lloyd J, Tocchetti R. Current concepts in the management of dental extractions for patients taking warfarin. Aust Dent J 2003;48(2):89-96. 20. Lockhart PB, Gibson J, Pond SH, Leitch J. Dental management considerations for the patient with an acquired coagulopathy. Part 2: Coagulopathies from drugs. Br Dent J 2003;195(9):495-501. 21. Ansell J, Hirsh J, Poller L, Bussey H, Jacobson A, Hylek E. The pharmacology and management of the vitamin K antagonists. The Seventh ACCP Conference on Antithrombotic and Thrombolytic Therapy. CHEST 2004;126(3):204S-233S. 22. Baker RI, Coughlin PB, Gallus AS, Harper PL, Salem HH, Wood EM: the Warfarin Reversal Consensus Group. Warfarin reversal: consensus guidelines, on behalf of the Australasian Society of Thrombosis and Haemostasis. Med J Aust 2004;181(9):492-7. 23. Ellis SL, Linnebur SA, Astroth JD, Valuck RJ. Differences between physician, dentist, and pharmacist recommendation for anticoagulation management in patients undergoing dental procedures [abstract]. Pharmacotherapy 2004;24(10):1438. 24. Muthukrishnan A, Bishop K. An assessment of the management of patients on warfarin by general dental practitioners in South West Wales. Br Dent J 2003;195(10):567-70. 25. Wahl MJ. Altering anticoagulation therapy: a survey of physicians. J Am Dent Assoc 1996;127(5):625-38. 26. Blinder D, Manor Y, Martinowitz U, Taicher S. Dental extractions in patients maintained on continued oral anticoagulant: comparison of local hemostatic modalities. Oral Surg Oral Med Oral Pathol Oral Radiol Endod 1999;88(2):137-40. 27. Sindet-Pedersen S, Ramstrom G, Bernvil S, Blomback M. Hemostatic effect of tranexamic acid mouthwash in anticoagulant-treated patients undergoing oral surgery. N Engl J Med 1989;320(13):840-3. 28. Ramstrom G, Sindet-Pedersen S, Hall G, Blomback M, Alander U. Prevention of postsurgical bleeding in oral surgery using tranexamic acid without dose modification of oral anticoagulants. J Oral Maxillofac Surg 1993; 51(11):1211-6.

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29. Al-Belasy FA, Amer MZ. Hemostatic effect of n-butyl2-cyanoacrylate (histoacryl) glue in warfarin-treated patients undergoing oral surgery. J Oral Maxillofac Surg 2003;61(12):1405-9. 30. Carter G, Goss A. Tranexamic acid mouthwash: a prospective randomized study of a 2-day regimen vs. 5-day regimen to prevent postoperative bleeding in anticoagulated patients requiring dental extractions. Int J Oral Maxillofac Surg 2003;32(5):504-7. 31. Carter G, Goss A, Lloyd J. Tranexamic acid mouthwash versus autologous fibrin glue in patients taking warfarin

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undergoing dental extractions: a randomized prospective clinical study. J Oral Maxillofac Surg 2003;61(12): 1432-5. 32. Della Valle A, Sammartino G, Marenzi G, Tia M, Espedito di Lauro A, Ferrari F, et al. Prevention of postoperative bleeding in anticoagulated patients undergoing oral surgery: use of platelet-rich plasma gel. J Oral Maxillofac Surg 2003;61(11):1275-8. 33. Ardekian L, Gaspar R, Peled M, Brener B, Laufer D. Does low-dose aspirin therapy complicate oral surgical procedures? J Am Dent Assoc 2000;131(3):331-5.

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