Purpose: to evaluate the clinical and histological features of healing of three common types of surgical flap designs used in periapical surgery. \
•N= 6 pure bred female beagles (13-34 months in age)
•The dogs were anesthetized.
•A marker was placed on the buccal surface of tooth #25, 2 mm from the crest of the free marginal gingiva.
•Each surgical site was infiltrated with 1.8 ml of lidocaine with 1:50000 epinephrine.
•A semilunar incision, horizontal intrasulcular incision was made. (The distance from the composite marker to the crest of the alveolar bone was measured) and submarginal incision in the attached gingiva. The upper left quadrant was used as the control ( no surgical procedure).
•The time during the surgical flap retraction and bone exposure was from 5 to 7 minutes.
•No surgical pack postoperatively, no food on the day of surgery, Tylenol postoperatively.
•Photographs were taken preoperatively, immediately postoperatively and at was observed until 60 days after surgery.
•Tissue samples were removed immediately for histological examination.
Most highlighted Results:
•Inflammatory changes persisted longer in the semilunar and intrasulcular incisions (retarded healing).
•The semilunar and intrasulcular incisions demonstrated a delay in histologically observable mature collagen fibers and its realignment with adjacent tissues.
•Loss of alveolar bone occurred with the intrasuIcular incision.
•Visible scarring occurred in the submarginal and semilunar incisions.
The submarginal incision is the flap design of choice in periapical surgery when not contraindicated by the anatomical location of the lesion or by insufficient attached gingival tissue