(This phrase acts like a noun. It is the direct object of the verb stopped. This phrase is a gerund phrase.) I stopped believing in Santa Claus when my mother took me to see him in a department store, and he asked for my autograph. (This phrase acts like a noun. It is the subject of the adverbial clause when my mother took me to see him in a department store.) I stopped believing in Santa Claus when my mother took me to see him in a department store, and he asked for my autograph.  It is the object of the preposition for.)
Ive googled 'white in extraction site'(!) and had some conflicting info: 'The white material is the blood clot; your rinsing has merely washed away the red blood cells and left the clotted fibrin material, which is white. This is normal, and is of no concern'. The second: 'White color in the extraction cavity...
As a natural way of cleansing the tooth socket, the body will send more blood to the wound site, triggering bleeding after the performed surgery. Depending on how difficult was, the amount of blood secreted may vary. However, blood clot should be promoted within 24 hours after the surgery. Your dentist will ask you to bite a cotton pad on gently within first few hours to promote blood clot. On the first day, swelling and pain might still be excruciating, causing extreme discomfort while eating, even talking and opening the mouth.