Blood investigations

2. BLOOD INVESTIGATIONS
IN
DENTAL PRACTICE
Presented by:
Dr.Ayesha Taha
JR I
Department of Pedodontics
and Preventive Dentistry
SPPGIDMS, Lucknow

3. CONTENT
INTRODUCTION
HAEMOSTASIS
SIGNIFICANCE OF BLOOD INVESTIGATION
COLLECTION OF BLOOD SAMPLE
TYPES OF HEMATOLOGICAL INVESTIGATIONS
•Complete Blood Count
•WBC count
•Differential Leukocyte count
•Hemoglobin
•Hematocrit
•Erythrocytes indices
•Platelets
•Bleeding time

4. •Capillary Fragility Test
•Clotting Time
•Erythrocyte Sedimentation Rate
HEMATOLOGICAL INVESTIGATIONS (not so
frequent in dentistry)
•Prothrombin Time
•Partial Thromboplastin Time
•INR
OTHER BLOOD TESTS
DENTAL MANAGEMENT OF BLEEDING DISORDER
CONCLUSION

5.  Various laboratory Investigations are sometimes required
for diagnosis and treatment planning of disorder related to
oral cavity.
 These can detect abnormalities such as
• Infection
• Anaemia
• Allergies
 Blood is also examined for grouping and cross-matching
INTRODUCTION

6. A NORMAL TEST result is just as significant as an abnormal
result.
A normal result does not mean that the test was unnecessary.
When a result is normal, it not only helps to rule out diseases,
but it also establishes a baseline for the clinician.

7. Either whole blood is used to count blood cells, or the blood cells
are separated from the fluid that contains them. This fluid is called
Plasma or Serum.
• Blood to be separated for serum
samples is collected in a plain clotting
tube (containing beads treated with a
clotting activator).
•Blood NOT to be separated for serum
samples is collected in a tube containing
lithium heparin (or beads treated with
lithium heparin).

8. 1. Vascular phase :Vasoconstriction, immediately
2. Platelet phase : Adhesion & aggregation,Platelet plug
formation.
3. Coagulation phase : later, contains extrinsic & intrinsic
pathways
4. Metabolic (fibrinolytic) phase: release antithrombotic
agents.
HAEMOSTASIS

10. SIGNIFICANCE OF BLOOD
INVESTIGATION
Blood investigation helps in diagnosing
• Leukopenia
• Thrombocytopenia
• Myeloma
• Anemia *Iron deficiency
*Aplastic
*Sickle cell anemia
• Thalassemia
• Acute and Chronic leukemia
• liver disease
• Myxedema
•Diabetes

11. COLLECTION OF BLOOD SAMPLE
•CAPILLARY BLOOD
SPECIMENS: The specimen is
obtained by pricking the patient`s
finger .
•VENOUS BLOOD SPECIMEN:
Most Commonly used method.
Venipuncture is usually performed
in ANTECUBITAL vein.

12. •WBC count
•Differential
Leukocyte count
•RBC count
•Hemoglobin
•Hematocrit
•Erythrocytes indices
•Platelet Count
•Bleeding time
•Capillary Fragility Test
•Clotting Time
•Erythrocyte Sedimentation Rate
TYPES OF HEMATOLOGICAL
INVESTIGATIONS
Complete
Blood Count

13. COMPLETE BLOOD COUNT
Complete blood count (CBC) is one of the most commonly ordered
blood tests.
The complete blood count is the calculation of the cellular (formed
elements) of blood.

14. What are the components of the complete blood count (CBC)?
The complete blood count, or CBC, lists a number of many
important values. Typically, it includes the following:
• White blood cell count (WBC or
leukocyte count)
• WBC differential count
WBC
• Red blood cell count (RBC or
erythrocyte count)
• Hematocrit (Hct)
• Hemoglobin (Hbg)
• Mean corpuscular volume (MCV)
• Mean corpuscular
hemoglobin (MCH)
• Mean corpuscular hemoglobin
concentration (MCHC)
RBC
• Platelet countPLATELET

15. •White blood cell count (WBC) is the number of white
blood cells in a volume of blood.
•This can also be referred to as the Leukocyte Count
•It can be expressed in international units =
4.3 to 10.8 x 109 cells per liter.
• Normal range of WBC=
4,500 - 10,000 cells/mm3 of blood.
•Number of cells are usually counted with the help of
Neubauer’s counting chamber
WBC/Leukocyte Count

17. A high white blood cell count usually indicates:
1. An increased production of white blood cells to fight an
infection
2. A reaction to a drug that increases white blood cell
production
3. A disease of bone marrow, causing abnormally high
production of white blood cells
4. An immune system disorder that increases white blood cell
production.

18. Specific causes of Leukocytosis:
1. Infection- Acute and Chronic
2. Leukaemia
3. Polycythemia
4. Trauma
5. Exercise , Stress and fear
6. After general anesthesia
7. Allergy
8. Drugs, such as corticosteroids and epinephrine
9. Rheumatoid arthritis
10. Smoking

19. Specific causes of Leukopenia:
1. Aplastic anaemia
2. Influenza, measles and Respiratory tract infection
3. Catarrhal Jaundice
4. Early Leukaemia
5. Depression of Bone marrow
6. Drug and chemical toxicity
7. Shock

20. WBC
Granulocytes
Neutrophils Eosinophils Basophils
Agranulocytes
Lymphocytes Monocytes
White blood cell (WBC) differential count:
White blood cells are comprised of several different types of
cells that are differentiated, or distinguished, based on their size
and shape.
Differential Count WBC

21. Normal values:
• Granulocytes (or polymorphonuclears)
Neutrophils:2.0–7.0×109/l (40–80%)
Eosinophils: 0.02–0.5×109/l (1–6%)
Basophils: 0.02–0.1×109/l (< 1–2%)
• Agranulocytes (or mononuclear)
Lymphocytes: 1.0–3.0×109/l (20–40%)
Monocytes: 0.2–1.0×109/l (2–10%)

22. CLINICAL SIGNIFICANCE
Neutrophils
INCREASES in: DECREASES in:
Inflammatory disease Aplastic Anaemia
Stress Cyclic Neutropenia
Exercise Malignant Neutropenia
Pregnancy Early Leukemia
Infection
Excitement
Eosinophils
INCEASES in: DECREASES in:
Parasitic infections Immune defect
Hypersensitivity/ Acute stress
Allergic responses Typhoid Fever
Scarlet Fever Aplastic Anaemia

23. Basophils
INCREASES in: DECREASES in:
Chronic leaukemia Acute Infection
Myelofibrosis Severe injury
Polycythemia
Lymphocytes
INCEASES in: DECREASES in:
Lymphocytic Leukemia Aplastic Anaemia
Mumps
Whooping Cough
Chronic Infection

24. •Monocytes
INCREASES in: DECREASES in:
Hodgkin disease Aplastic Anaemia
Monocytic Anaemia Acute Leukemia
Malaria – Kala Azar
SABE
TB

25. RBC Count
•Red Blood cell count (RBC) signifies the number of red blood
cells in a volume of blood.
• Normal range : 4.2 to 5.9 million cells/cmm.
• This can also be referred to as the Erythrocyte count
• It can be expressed in international units:4.2 to 5.9 x 1012 cells
per liter.

26. •An increase in red blood cell mass is known as Polycythemia.
•Polycythemia Vera is a disease of unknown origin that results in an
abnormal increase in red blood cells.
•CAUSES:
•Normal physiological increases in the RBC count occurs at high
altitudes or after strenuous physical training.
• Drugs: Gentamicin
Methyldopa
•Smokers also have a higher number of red blood cells than non-
smokers.
INCREASE in RBC Count

27. DECREASE in RBC Count
•Massive RBC loss, such as acute hemorrhage
• Abnormal destruction of red blood cells
• Lack of substances needed for RBC production
• Chemotherapy or radiation side effects from treatment of bone
marrow malignancies such as leukemia can result in bone marrow
suppression.

28. HEMOGLOBLIN
Hemoglobin is the protein molecule within red blood cells that
carries oxygen and gives blood its red color.
•Normal range =13-18 grams per dl for men and
12-16 grams per dl for women
•International units= 8.1 to 11.2 millimoles/L for men
7.4 to 9.9 milimoles/L for women

29. Increase in Hb
*Benign neoplasm of
brain and CNS
*Carcinoma of the
kidney
* Cholera
*Diarrhoea
*Pheochromocytoma
*Polycythemia vera
Decrease in Hb
*Aplastic anaemia
*Anti-retroviral drugs for HIV
infection Cirrhosis
*Hodgkin's lymphoma
*Hypothyroidism
*Kidney disease
*Lead poisoning
*Leukaemia
*Multiple myeloma
*Vitamin deficiency
anaemia

30. A low haemoglobin count can also be due to blood loss
Diseases and conditions that cause the body to destroy red
blood cells faster than they can be made:
• Enlarged spleen (splenomegaly)
• Sickle cell anemia
• Thalassemia
• Vasculitis

31. •It is a measure of volume percent of packed red blood cells to
that of whole blood.
•This is usually measured by spinning down a sample of blood
in a test tube, which causes the red blood cells to pack at the
bottom of the tube.
Normal results :
Male: 40.7 - 50.3%
Female: 36.1 - 44.3%
Hematocrit (Hct)

32. High Hematocrit may be due to:
•Congenital heart disease
•Cor pulmonale
•Dehydration
•Erythrocytosis
•Low blood oxygen levels (hypoxia)
•Pulmonary fibrosis
•Polycythemia vera
Low Hematocrit may be due to:
•Anaemia

33. Erthrocytes Indices
•To evaluate the nature of Anaemia, assistance is obtained by
calculating standard indices relating to the size of RBCs.
•By measuring these indices we can classify anaemia as
Microcytic, Macrocytic And Normocytic and Hypochromic
and Normochromic.
Types
MCH MCHC MCV

34. The Haemoglobin content of erythrocyte is referred to as the Mean
Corpuscular Haemoglobin(MCH) expressed in picogram of
haemoglobin per cell.
MCH = Haemoglobin concentration (g/dl) × 100
RBC in million/mm3
Mean Corpuscular Haemoglobin (MCH)

35. The concentration of Haemoglobin in the erythrocyte is referred to
as the Mean Corpuscular Haemoglobin Concentration.(MCHC)
expressed in picogram of haemoglobin per cell.
MCHC = Haemoglobin concentration (g/dl) × 100
Hematocrit
Mean Corpuscular
Haemoglobin Concentration (MCHC)

36. The average red cell volume is referred to as the Mean Corpuscular
Volume(MCV) .
It is expressed in cubic microns per cell.
MCHC = Hematocrit × 100
RBC in million /mm3
Mean Corpuscular Volume (MCV)

37. Different types of Anaemia and Indices
Types of
Anemia
MCV MCH MCHC
Microcytic
Hypochromic
Decreased Decreased Decreased
Macrocytic
Normochromic
Increased Increased Normal
Normocytic
Normochromic
Normal Normal Normal

38. The common causes of Microcytic & Hypochromic Anemia
(decreased MCV and MCH) are:
•Iron deficiency anemia
•Anemia of chronic disease
•Thalassemia
•Sideroblastic anemia
The common causes of Macrocytic Anemia (increased MCV
and MCH) are as follows:
•Folate or Vit B12 deficiency anemia
•Liver disease
•Hemolytic or Aplastic anemias
•Hypothyroidism
•Excessive alcohol intake
•Myelodysplastic syndrome

39. The common causes of Normocytic And Normochromic
Anemia (normal MCV, MCH and MCHC) are:
•Anemia of chronic disease
•Acute blood loss
•Hemolytic anemia, such as autoimmune hemolytic anemia,
hereditary spherocytosis, or nonspherocytic congenital hemolytic
anemia (G6PD deficiency, other)
•Anemia of renal diseases.

40. PLATELET/THROMBOCYTE COUNT
The number of platelets in a specified volume of blood.
Platelets play a vital role in Haemostasis.
Normal range (Adult) =150,000 to 400,000/ cmm of blood.
(150 to 400 x 109/ L)
Normal range(Children) =150,000-450,000 /cmm of blood.
(150-450 x 109/L)

41. Interpretation of Platelet count
THROMBOCYTOSIS:
Post operative phase
Pregnancy
Post partum phase
Haemolytic Anemia
Trauma
Polycythemia vera
Chronic myelocytic leukemia
THROMBOCYTOPENIA:
Acute leukemia
Idiopathic thrombocytopenic
purpura
Aplastic anemia
Effect of chemotherapy
Hypersplenism

42. It Measures the time required for hemostatic plug to form.
Lack of any clotting factor or platelet abnormalities will
prolong the bleeding time.
It is used to screen disorders of platelet function and
thrombocytopenia
Normal Bleeding Time: 2 - 6 minutes
Methods are: Duke method and Ivy’s method
Bleeding Time

43. An abnormal Bleeding time- It is usually the result of
abnormalities in the structure / abilities of capillaries to contract
or abnormalities in the number (Thrombocytopenia) and
functional integrity of platelets.
Interpretation of bleeding time

44. •It is the test of the ability of superficial capillaries of the skin
and forearm and hands to withstand an increased intraluminal
pressure and a certain degree of hypoxia.
•It is a clinical diagnostic method to determine hemorrhagic
tendency.
It is done by occluding the upper veins of the upper arm
with a blood pressure cuff for five minutes.
Also known as Tourniquet Test/ Rumpel Leede Test
Positive result: unequivocal petechiae seen distal to cuff.
Negative result: If only 1 or 2 petechiae seen distal to cuff.
Capillary Fragility Test

46. Time required for coagulation to occur in a sample of whole
blood outside the body is known as Clotting Time.
Normal time- 3 to 7 minutes
Method are:
• Capillary tube method
• Le and white’s test tube method
Clotting Time

47. An abnormal Clotting time- It is usually prolonged in diseases
affecting stages of coagulation.
It is also increased in:Cirrhosis
Hemophilia A and B
Factor XI deficiency,
Hypofibringenemia and
Heparin & Dicumarol therapy.
Interpretation of Clotting time

48. •It is the measure of the rate at which RBCs sediments in
a period of one hour.
•Also called as Sedimentation Rate or Westergren ESR
•It is a common haematology test.
•It is a non-specific measure of inflammation.
•Also helpful in following progress of some chronic
infections (TB and Osteomylelitis)
•Done in Westergren pipette
Normal ESR
Male: 2-5 mm per hr
Female: 10- 15 mm per hr
Erythrocyte Sedimentation Rate (ESR)

49. Interpretation of ESR
ESR increased:
Tuberculosis
Osteomyelitis
Rheumatic fever
Myocardial infarction
Rheumatoid arthritis
Chronic lung abscess
Hodgkin's disease
Leukaemia
ESR decreased:
Congestive cardiac failure
Polycythemia
Severe dehydration like cholera
Physiologic condition where
ESR is increased:
Pregnancy: After intake of full meal

50. HEMATOLOGICAL
INVESTIGATIONS
(not so frequent in dentistry)
•Prothrombin Time
•Partial Thromboplastin Time
•INR

51. It is the time in seconds that is required for fibrin threads to
form in citrated or oxalated plasma.
It is used to check the extrinsic pathway factor (F 7) and the
common pathway ( F 5, 10 , prothrombin and fibrinogen).
Normal range: 11 to 15 seconds
Prolonged time indicates abnormal or prolonged Prothrombin
time.
It gets prolonged when plasma level of any factor is below
10% of its normal value
PROTHROMBIN TIME

52. It is the time in seconds that is required for a clot to form in a
sample of oxalated plasma.
It is used to check the intrinsic system (8, 9, 11, 12) and the
common pathways (5, 10, prothrombin and fibrinogen).
Normal range: 25-35 seconds
If PTT is prolonged it indicates deficiency of factor 8 or 10
PARTIAL THROMBOPLASTIN TIME

53. INR:
INTERNATIONAL NORMALIZED RATIO
The International Normalised Ratio (INR) is a laboratory
measurement of how long it takes blood to form a clot. It is
used to determine the effects of oral anticoagulants on the
clotting system.
It is the ratio of Patient’s Prothrombin Time to that of normal
Prothrombin time.
INR= Patient`s PT
Normal PT

54.  It should be noted that INR is used to monitor Anti
coagulant therapy & NOT be used as coagulation screening
test
 INR values of 5.0 or greater indicate a serious risk of
spontaneous bleeding episodes.
NORMAL RANGE: 0.8-1.2 (No anticoagulant therapy)
02-03 (On anticoagulant therapy)
• Infiltration anesthesia , scaling and root
planning
INR <3
• Block anesthesia , minor surgery ,
extraction
INR <2
• Major surgeryINR <1.5

55. OTHER BLOOD TESTS

56. RENAL TEST
Creatinine is a chemical molecule that is present in the
serum of the blood.
It's produced from another molecule, Creatine, which is a
component of muscle.
The amount of Creatinine the body produces each day
depends on the person's muscle mass.
The normal serum Creatinine range for Men= 0.5-1.5 mg/dL.
Women is 0.6-1.2 mg/dL

57. SIGNIFICANCE:
When the kidneys are functioning normally, the amount of
Creatinine in the serum should remain even.
When they're not working properly, the serum Creatinine
level increases.

58. •Blood Urea Nitrogen (BUN) is another measure of wastes
(urea) in the blood.
•Urea is produced from the breakdown of protein already in
the body and protein in your diet.
The normal BUN level = 7-20 mg/dL in adults and
= 5-18 mg/dL in children.
Blood Urea Nitrogen (BUN)
SIGNIFICANCE:
•A high BUN usually means that kidney function is less than
normal, but other factors may affect the BUN level.
•Sometimes a low BUN may also mean that not enough intake
of protein.

59. BLOOD GLUCOSE
Normal Blood Sugars Level:
•A normal fasting (no food for eight hours) 70 and 99 mg/dL
•Post Prandial (two hours after eating) upto140 mg/dL
•Random Blood sugar level: 70-140mg/dl
Diabetes is diagnosed by any one of the following:
•Two consecutive fasting blood glucose tests that are equal to or
greater than 126 mg/dL
•Any random blood glucose that is greater than 200 mg/dL
•A 2-hr Oral glucose tolerance test value over 200 mg/dL

60. Complications of High Blood glucose level include:
•Poor wound healing
•Infection
•Electrolyte imbalance
•Diabetic ketoacidosis

61. Complications of Low Blood glucose level include:
•Loss of consciousness(syncope)
•Seizure

62. The most common HIV test, the Enzyme-Linked Immuno
Sorbent Assay, or ELISA (also called EIA), is used to detect
HIV antibodies in a sample of the blood.
HIV TEST

63. Although HIV tests are very sensitive, they can produce
false-positive results.
So ELISA HIV tests must be confirmed with another HIV
test, such as a Western blot or Indirect
immunofluorescence assay (IFA).

64. Antibodies won't show up in the blood or body fluid
immediately after infection.
There is a "window period" of six to 12 weeks, and
sometimes several months, before the body starts
producing antibodies to the virus. So even if tested
negative within a few weeks of being exposed to HIV, one
should get tested again at three months and six months.

65. TEST FOR HEPATITIS B
It is important to identify the type of hepatitis virus causing
infection to prevent its spread and choose the proper treatment
since it is transmitted through infected body fluids.
It also can be transmitted from a pregnant woman to her child
at or near the time of birth.
There are several different HBV tests
• Hepatitis B surface Antigen (HBsAg) - this tests is done
directly for the presence of virus. `
•Hepatitis B core Antibody (HBcAb or anti-HBc)
•Hepatitis B surface Antibody (HBsAb or anti-HBs)

66. Dental Management of
Bleeding Disorder

67. Haemostatic
agents
LOCAL
Mechanical Thermal Chemical
SYSTEMIC

68. LOCAL HAEMOSTATIC
MEASURES
MECHANICAL METHODS:
•Pressure
•Use of Haemostats
•Suture and Ligations
•Embolization of vessels using steel coils, polyvinyl
alcohol foam, gel foam, silicon spheres, and
methyl methacrylate.

69. THERMAL METHODS:
•Cautery
•Electrocautery
•Cryosurgery
•Argon beam coagulators
•Lasers
CHEMICAL METHODS:
•Astringent agents: Monsel solution and Tannic acid
•Bone wax
•Thrombin
•Gelfoam
•Oxycel
•Surgicel
•Fibrin glue
•Adrenaline

70. SYSTEMIC HAEMOSTATIC
MEASURES
•Whole Blood
•Platelet rich plasma: one unit can raise the platelet count
by 7000-10,000 cells/cmm of blood
•Fresh frozen plasma: It contain all the coagulation factors.
•Cryoprecipitate: Contain factor VIII, XIII and vWB
•Adrenochrome monosemicarbazon and ethamsylate

71. 90% of inherited haemostatic disorder consist of
Haemophilia A,B and Von Wilibrand’s disease.
MANAGEMENT OF HAEMOPHILIA A and B
PATIENTS:
Replacement therapy :
1. Platelet concentrate
2. Fresh frozen plasma
3. Factor VIII,IX concentrate : Hemophilia A
4. Factor IX concentrate : Hemophilia B
5. Desmopressin
 Antifibrinolytic therapy:
1. Epsilon-aminocaproic acid (EACA, Plaslloid)
2. Tranexamic acid (AMCA, Transamin)

72. MANAGEMENT OF PATIENTS WITH VON
WILLEBRAND DISEASE:
Desmopressin
Replacement therapy
1. Platelet concentrate
2. Fresh frozen plasma
 Antifibrinolytic therapy:
1. Epsilon-aminocaproic acid (EACA, Plaslloid)
2. Tranexamic acid (AMCA, Transamin)

73. CONCLUSION
Reviewing clinical laboratory test results about a
patient's condition can provide valuable information for
Diagnosis and management of orofacial conditions
Guidance on assessing the patient's ability to tolerate
the proposed dental treatment
A prognosis based on a particular treatment

74. REFRENCES:
•Ganong WF. Review of medical physiology. 21st Edition. Lange
medical publishers. 2004.
• Cyril KA, Eric N, Norman J. Samson wright’s applied
physiology. 13th Edition. Oxford university press. 2002.
• Chaudhary SK. Conscise medical physiology. 2nd Edition. New
central book agency private limited. 2003.
• Taylor JB. Physiological basis of medical practice. 12th Edition.
Wavery pvt ltd. 2001.
• Kumar CR. Basic pathology. 7th Edition. Elsevier publications.
2003
• Mohan H. Essential Pathology for Dental students. 2nd Edition.
Jaypee publications. 2005
• Tandon S. Textbook of Pedodontics. 1st Edition. Paras medical
publications. 2003.
•Textbook of Oral Medicine. 2nd edition. Paras Publications.2010