PROGRESSIVE TISSUE CHANGES. 



185 



tablish hyperemia and in some cases slight inflammation ac- 

 companied by a serous exudation and a leucocytic immigration. 

 The hemorrhagic extravasate is gradually disintegrated and re- 

 moved by phagocytes and at the same time, there is enlarge- 

 ment and extension by multiplication of the marginal tissue 

 cells of the wound into the coagulum which serves as a support 

 for the regenerating- tissue. 



Vascularization accompanied by fibrous formation initiates 

 the process of regeneration in the healing of a wound 

 by primary union. Vascularization is visuall3r limited because 

 of the small size of the wounds. The newljr formed vessels 

 are capillaries and supplv the regenerating tissue. Fibrous 

 tissue is produced in sufficient quantities to replace all tissues 

 destroyed. 



Diisintegration of the coagulum and regeneration of new tis- 

 sue thus proceed xintil the newly formed tissue has entireh^ re- 

 placed the extravasate. IHie scab is finulv held upon the wound 



-a 



a. Fibrinous exudaL 



b. Regeneration of epithelium. 



Fig. 106. — Wound Healing by first intention. 



Ui Mruliifralion of vessels. *-'■ Bottom 



Leucocytes- 



