healing by primary intention, secondary intention explained in flowcharts and videos are added. healing of fracture and extraction sockets are also added in the form of flowcharts for better understanding

1. WOUND
HEALING
PRESENTED BY :
Dr. Priyanka Madhavan

2. CONTENTS :
• Introduction
• Types of wound
• What is Healing ?
• Phase of healing
• Types of healing
a) Primary intention
b) Secondary intention
• Fracture healing
• Socket healing
• Factors affecting wound healing
• Complication
• Conclusion
• References

3. INTRODUCTION
What is a wound ??

4. WOUND :
• It is a circumscribed injury which is caused by external force and it can involve any
tissue and organ.
• A cut or break in the continuity of any tissue, caused by injury or operation.
-(Baillière’s 23rd Ed)

5. CLASSIFICATION OF WOUND

6. BASED ON TYPE OF WOUND
• Clean incised wound
• ii. Lacerated wound
• iii. Bruising and contusion
• iv. Haematoma
• v. Puncture wound
• vi. Abrasion
• vii. Crush injury
• viii. Injuries to bone and joint (maybe open or closed)
• ix. Injuries to nerve (either clean cut or crush)
• x. Injuries to arteries and veins
• xi. Penetrating wounds

7. CLASSIFICATION OF SURGICAL WOUNDS
• a) Clean wound
• b) Clean contaminated wound
• c) Contaminated wound
• d) Dirty infected wound

8. CLASSIFICATION BASED ON THICKNESS OF
WOUND
• Superficial wound
• Partial thickness
• Full thickness
• Deep wounds
• Complicated wounds
• Penetrating wound

9. WHAT IS HEALING ?

10. HEALING
• Healing is the body’s response to injury in an attempt to restore normal structure
and function.
• The process of healing involves 2 distinct processes:
A. REGENERATION
B. REPAIR

11. REGENERATION & REPAIR
• Regeneration is when healing takes place by proliferation of parenchymal cells and
usually results in complete restoration of the original tissues.
• Repair: It is a healing outcome in which tissues do not return to their normal
architecture and function.

12. PHASE OF WOUND HEALING

13. THREE PHASE OF WOUND HEALING
• The inflammatory phase (1-3days)
• The proliferative phase (3days – 3weeks)
• The remodeling phase (3weeks – 2years)
Granulation tissue formation
neovascularisation
wound contraction
epithelialization

14. TYPES OF WOUND HEALING
a) Primary intention
b) Secondary intention

15. PRIMARY INTENTION
Healing of wound with following characteristics:
• Clean and uninfected
• Surgically incised
• Without much loss of cells and tissue
• Edges of wound are approximated by surgical sutures.

16. SECONDARY INTENTION
Healing of wound with following characteristics:
• Infected wound
• Not surgically incised
• Loss of cells and tissue
• Edges of wound cannot be approximated by surgical sutures.
• Wounds with unopposable edges

17. STAGES OF WOUND HEALING

18. STAGES OF PRIMARY WOUND HEALING
1) Initial hemorrhage inflammatory phase
2) Acute inflammatory response
3) Epithelial changes proliferative phase
4) Organization maturation & remodeling phase
5) Suture tracks

19. INITIAL HEMORRHAGE
Injury
Bleeding fills the wound
Clot formation
(prevents wound from dehydration and infection)

20. INITIAL HEMORRHAGE

21. ACUTE INFLAMMATORY RESPONSE
After 24 hours
Appearance of neutrophils
Replacement of neutrophils by macrophage
By 3rd day

22. ACUTE INFLAMMATORY RESPONSE

23. EPITHELIAL CHANGES
Basal cells from cut surface
Proliferate & migrate to incisional space
Forms epithelial spur
In 48 hrs, wound is covered by layer of epithelium
Scab formed is cast off
Basal cell divides & by 5th day, multiple layer of epithelium is formed.

24. EPITHELIAL CHANGES

25. ORGANIZATION
By 3rd day, fibroblast appear.
Invade to wound area
By 5th day, collagen fibrils starts forming
In 4 weeks, scar tissue with scanty cellular & vascular elements is formed
Few inflammatory cells are also seen

26. ORGANIZATION

27. SUTURE TRACT
Each suture tract is a separate wound & heals in the same way like other wounds
Sutures removed at 7th day
Scar formed is neat due to close apposition of wound

28. H/P OF PRIMARY HEALING

29. STAGES OF SECONDARY WOUND HEALING
1) Initial hemorrhage inflammatory phase
2) Acute inflammatory response
3) Epithelial changes proliferative phase
4) Granulation tissue formation maturation & remodeling phase
5) Wound contraction

30. GRANULATION TISSUE FORMATION
Main bulk formed due to granulation tissue
Excessive proliferation of fibroblast & neovascularization occurs
Initially, granulation tissue – red, fragile & granular
Later, upon maturation & increased collagen – pale
Tissue like hair follicle and sweat glands are not replaced

31. GRANULATION TISSUE FORMATION

32. WOUND CONTRACTION
Wound contraction – important step
Myofibroblast plays an important role
Wound contracts to 1/3rd to 1/4th of its original size
Occurs together with granulation tissue formation

33. WOUND CONTRACTION

34. H/P OF SECONDARY HEALING

35. FRACTURE HEALING
Primary & secondary union

36. STAGES OF FRACTURE HEALING
• PROCALLUS FORMATION
i. Hemorrhage
ii. Local inflammatory response
iii. Ingrowth of granulation tissue
iv. Callus composed of woven bone and cartilage
• OSSEOUS CALLUS FORMATION
• REMODELLING

37. PROCALLUS FORMATION - CALLUS COMPOSED
OF WOVEN BONE AND CARTILAGE
Cells of inner layer of periosteum lay down collagen & osteoid in granulation tissue
Osteoid  calcification = woven bone callus
Woven bone callus, unites the gap and forms fusiform shape to the union
This callus contains – woven bone & cartilage
This stage is also called as provisional callus formation.
(external, intermediate & internal callus)

38. OSSEOUS CALLUS FORMATION
Procallus acts as scaffold
Osseous callus (lamellar bone) formed over the procallus
Woven bone  cleared by osteoclast ; cartilage  disintegrate
Osteoblast invade and lay down osteoid, neovascularization
Haversian system is formed

39. REMODELING
Osteoblastic and osteoclastic functions together
Remodelling  remodels the united bone
New bone formed resembles the old bone
External callus clears
Intermediate callus  cortex
Internal callus  bone marrow

40. HEALING OF EXTRACTION SOCKET

41. STAGES OF EXTRACTION SOCKET HEALING
• Immediately after extraction
• First week wound
• Second week wound
• Third week wound
• Fourth week wound

42. IMMEDIATELY AFTER EXTRACTION
Extraction of tooth
Bleeding and clot formation in socket
24-48hours hemodynamic changes and inflammatory reaction takes place

43. FIRST WEEK WOUND
Proliferation of fibroblast in connective tissue
Clot starts to replace by  granulation tissue
Crest of alveolar bone  osteoclastic activity
Endothelial cell proliferation of PDL occurs

44. SECOND WEEK WOUND
Neovascularisation in the centre of clot
Wall of the socket appears frayed  degeneration of PDL
Trabeculae of osteoid can be seen
Epithelial proliferation occurs over the surface of wound

45. THIRD WEEK WOUND
Clot  granulation tissue
Young trabeculae of osteoid is formed around entire periphery of socket
Crest of alveolar bone gets rounded off  osteoclastic activity
Complete epithelialization of surface

46. FOURTH WEEK WOUND
Continuous deposition and remodeling resorption of bone
This activity fills the entire socket space
roentgenographic evidence
of bone becomes prominent after 6th to 8th week.

47. FACTORS AFFECTING WOUND HEALING
Promotors & inhibitors of wound healing

48. FACTORS PROMOTING WOUND HEALING
LOCAL FACTOR :
• Ultraviolet radiation
SYSTEMIC FACTOR:
• AGE : Young age promotes wound healing

49. FACTORS INHIBITING WOUND HEALING
LOCAL FACTORS :
• Infection
• Poor blood supply
• Foreign bodies
• Ionizing Radiation
• Movement

50. FACTORS INHIBITING WOUND HEALING
SYSTEMIC FACTORS:
• Age
• Nutrition
• Generalized infection
• Administration of glucocorticoids
• Uncontrolled diabetes
• Hematological disturbances

51. COMPLICATIONS OF WOUND HEALING

52. COMPLICATIONS
• Infection
• Implantation
• Pigmentation
• Deficient scar formation
• Incisional hernia
• Hypertrophied scar & keloid formation
• Excessive contraction
• Neoplasia

53. COMPLICATION OF FRACTURE HEALING

54. COMPLICATION
• Fibrous union
• Non – union
• Delayed union

55. COMPLICATION OF EXTRACTION SOCKET

56. COMPLICATION
• Dry socket

57. CONCLUSION

59. REFERENCES
1. Mohan H. Textbook of pathology. Jaypee Brothers, Medical Publishers Pvt. Limited;
2018 Nov 30.
2. Robbins S. Textbook of pathology. The American Journal of the Medical Sciences.
1958 Jan 1;235(1).
3. Beldon P. Basic science of wound healing. Surgery (Oxford). 2010 Sep 1;28(9):409-12.
4. Hunt TK. The physiology of wound healing. Annals of emergency medicine. 1988 Dec
1;17(12):1265-73.
5. Young A, McNaught CE. The physiology of wound healing. Surgery (Oxford). 2011
Oct 1;29(10):475-9.