Frequently-asked Questions
Blood thinners are Aspirin, Clopidogrel, Warfarin, Coumadin, Heparin etc
Blood thinners are given to prevent blood clots in certain medical conditions like
- Deep Vein Thrombosis
- Pulmonary Embolism
- Cerebral Embolism
- Unstable Angina
- Heart Attack
- Atrial Fibrillation
- Disseminated Intravascular Coagulation
- Dialysis
- Prosthetic Heart Valves
- Angioplasty
- Stent Placement
Blood Laboratory Tests that Evaluate Hemostasis and Bleeding Disorders
| Laboratory Tests | Measures Normal Function | *Normal Values/Ranges | Importance in Diagnosing Bleeding Disorders | *Abnormal Values/Ranges |
| Platelet Count | Adequate platelet numbers | 150,000 to 450,000/mm3 | Assess thrombocytopenia or inadequate numbers of platelets | 100,000 cells/mm3 |
| Ivy Bleeding Time | Adequate platelet function | 2-10 minutes | Screening test for thrombocytopathy; von Willebrand’s disease | Prolonged time: >9-10 minutes |
| Platelet Function Tests | Assess function of platelets: attachment, activation, and aggregation | Discriminates between normal and abnormal function of platelets | ||
| Prothrombin Time (PT) | Assess the time it takes to form a fibrin clot when calcium and tissue factor are added to the plasma (extrinsic pathway: coagulation function of factor VII; common pathway: factors V, X, prothrombin and fibrinogen) | 11 to 15 seconds | Assess defects in the extrinsic pathway of the coagulation system: anticoagulant therapy (warfarin); Prothrombin deficiency, vitamin K deficiency; liver disease; antiplatelet drugs | Prolonged time: >30 seconds |
| International Normalized Ratio (INR) | Coagulation function of the extrinsic pathway: Factors V, VII, X, prothrombin and fibrinogen | 1.0 | Monitors oral anticoagulation therapy: warfarin | INR greater than 1.2 in patients not on anticoagulation therapy. In patients on anticoagulants, therapeutic range is between 2.0 and 3.5 |
| Partial Thromboplastin Time (activated aPTT) | Assess the time it takes to form a fibrin clot when calcium and partial thromboplastin containing phospholipids are added to the plasma (intrinsic pathway: coagulation function of factors VIII, IX, XI and XII | 25 to 40 seconds | Assess defects in the intrinsic pathway of the coagulation system: anticoagulant therapy (heparin); von Willebrand’s disease; hemophilia A and B | Prolonged time: 45 to 50 seconds |
| Thrombin Time | Thrombin is added to blood to convert fibrinogen to fibrin | 24 to 35 seconds | Assess defects in the conversion of fibrinogen to fibrin | Prolonged or beyond normal |
| *Normal values or ranges may vary among different laboratories | ||||
The therapeutic INR should be between 2.0 and less than 4.0 for most dental treatments. It depends on kind of procedure or treatment you will be requiring.. Some procedures might require us to consult your physician regarding your anticoagulation therapy. We might also advise you to stop your blood thinners based on invasiveness of the surgery after consulting your physician.
The INR should be done 24 hours before or on the morning of the surgery or dental appointment and let the lab fax the results to our office or email our office.
No you don’t need INR for all the dental procedures. You need to get INR test results for all the dental surgeries( Extractions, Periodontal Gum Surgeries, other oral surgeries like Biopsy, dento alveolar surgeries like Alveoplasty, vestibuloplasty, Dental Implants and Bone Grafting Procedures).
No. You can stop your blood thinners only at the advice of your physician. If you do not have recommendation from your physician then please do not stop your blood thinner. Some of the procedures can be done even when you are taking blood thinners. It depends upon the discretion of your Dental treatment Provider.