This document discusses hemostasis (stopping bleeding) and hemostasis disorders. It notes that hemostasis has three main steps: vasoconstriction, formation of a platelet plug, and formation of a fibrin clot. Hemostasis disorders can be caused by deficiencies in coagulation factors, platelet disorders, vascular disorders, or fibrinolytic defects. The document also discusses antiplatelet medications, which are used to prevent and treat arterial thrombosis by altering platelet activation. Antiplatelet medications like aspirin and clopidogrel can increase bleeding time but may still be within normal limits, and generally do not need to be stopped before routine dental procedures. Dentists must be aware of bleeding risks and properly evaluate patients,

1. Dr. Dineshwarran Rajendran
Klinik Pergigian Besar Kota
Bharu

2. Haemostasis
A process which causes bleeding to stop, meaning to keep
blood within a damaged blood vessel.
Hemostasis has three major steps:
1) vasoconstriction
2) temporary blockage of a break by a platelet plug
3) blood coagulation, or formation of a fibrin clot
Haemostasis disorder
A disorder which affects the normal heamostasis process
which can lead to abnormal bleeding.

3. Steps in
Haemostas
is

4. 1. Coagulation factor deficiencies
2. Platelet disorders
• Quantitative disorder (thrombocytopenia)
• Idiopathic
• Drug-induced (Antiplatelet medication)
• Collagen vascular disease
• Sarcoidosis
• Disseminated intravascular coagulation
• Leukemia
• Qualitative disorder
• Glanzmann thrombasthenia
• von Willebrand’s disease
• Drug-induced (Antiplatelet medication)
• Liver disease
3. Vascular disorders
4. Fibrinolytic defects
Types of Heamostasis Disorders

5. Definition
A group of drugs that that decrease platelet aggregation and
inhibit thrombus formation.
Uses
Prevention and treatment of arterial thrombosis
Treatment of established arterial thrombosis includes the use of
antiplatelet drugs and thrombolytic therapy. Antiplatelet drugs
alter the platelet activation at the site of vascular damage crucial
to the development of arterial thrombosis.
Example of Antiplatelet drugs
• Aspirin and Triflusal
• Dipyridamole
• Clopidogrel
• Epoprostenol

6. How do antiplatelet medications affect
bleeding time?
The effect on primary haemostasis is minimal in patients
without additional risk factors for impaired clotting.
Antiplatelet medications can double the baseline bleeding
time but this may still be within or just outside the normal
range. It has been reported that only 20% to 25% of
patients using aspirin have an abnormal bleeding time.

7. Antiplatelet medications DO NOT have to be stopped
before primary care dental surgical procedures
Patients taking
• low-dose aspirin (75mg-300mg daily)
• clopidogrel
• dipyridamole
should not have their medications stopped or altered prior
to dental surgical procedures in primary care.

8. Dentists must be aware of the impact of bleeding disorders
on the management of their patients. Proper dental and
medical evaluation of patients is therefore necessary
before treatment, especially invasive treatment. Patients
should be queried about any previous unusual bleeding
episode after surgery or injury, spontaneous bleeding and
easy or frequent bruising.
A clinically significant bleeding episode is when:
• continues beyond 12 hours
• causes the patient to call or return to the dental
practitioner or to seek medical treatment or
emergency care
• results in the development of hematoma or
ecchymosis within the soft tissues or
• requires blood transfusion

15. Patients taking antiplatelet medications will have a
prolonged bleeding time but this may not be clinically
relevant.
Postoperative bleeding after dental procedures can be
controlled using local haemostatic measures
Bleeding complications, while inconvenient, do not carry
the same risks as thromboembolic complications.
Patients are more at risk of permanent disability or death if
they stop antiplatelet medications prior to a surgical
procedure than if they continue it.
Published reviews of the available literature advise that
aspirin should not be stopped prior to dental surgical
procedures.