Clinical and Histological Evaluation of Tissue Healing in Beveled or Perpendicular Vertical Releasing Incision

ObjectivesThe aim of this investigation was to evaluate the clinical and histological differences in wound healing between beveled and perpendicular vertical releasing incisions in dogs.Material and MethodsFour male mongrel dogs were used in this investigation. In each quadrant, a vertical releasing incision was made on either the mesial or the distal aspect of the cuspid teeth of each animal all on the same day. The sites were randomly selected to either receive a beveled incision or a perpendicular incision. A sulcular muco-periosteal flap was raised, reapproximated, and then sutured using 3-0 Vicryl. The animals were evaluated daily for the first week, and then at different time intervals during this investigation. One animal was killed at each time interval of 9, 14, 21, and 28 days after surgery. One animal was killed at each time interval, and a bone block consisting of the cuspid teeth and their surrounding bone and soft tissues was harvested, formalin fixed, and paraffin embedded. Samples were sectioned serially and stained with hematoxylin-eosin. Specimens were evaluated using a microscope with magnification ranging from ×10 to ×400 by a histopathologist. Four indices were used for histologic evaluation.ResultsAt day 9 after surgery, a visible groove was seen in the marginal tissues of both perpendicular and beveled incisions. At day 9, both of the histologic sections showed less organized connective tissue and capillary networks with no significant difference in inflammation. In the 14-day samples, a depression was still present at the perpendicular incision sites, but not in the beveled incision group, where the groove was not visualized at all.In the 21- and 28-day samples, irregular capillary arrangements were seen in the connective tissue of the perpendicular incision groups with completely healed epithelium. There were no statistically significant differences noted histologically between the beveled and perpendicular incision groups noted at 9, 14, 21, or 28 days (P > .05).ConclusionBased on these findings, it appears that clinical and histologic healing of beveled or perpendicular releasing incisions are similar 28 days after surgery.