Observation of the mitochondria of the sulcular epithelium of clinically inflamed and clinically healthy gingiva.

Ten human males with an average age of 22 years, free from any known systemic disease, were selected for this study. Each subject had a mild gingivitis around at least one lower incisor tooth. This was confirmed by the color, contour, and consistency of the tissue. The area was probed for gingival sulcus depth and a radiograph confirmed that there was no interproximal bone involvement. A specimen was excised from the inflamed area and examined histologically for inflammatory cell density and an inflammatory index number was assigned to the tissue. The gingivitis was treated and personal oral hygiene instructions were explained to the subjects. Healing continued uneventfully for ten to twelve weeks. A second specimen was excised from near the original area, examined histologically, and an inflammatory index number was assigned to the tissue. The ultrastructure of the sulcular epithelium and the connective tissue adjacent to the sulcular epithelium of all specimens was examined at powers varying from 3,500 to 70,000. The sulcular epithelium showed no positively recognizable mitochondria. Mitochondria in the connective tissue adjacent to the basal layer of the sulcular epithelium were abundant and well formed. There was no correlation between the number and morphology of mitochondria in the treated and untreated specimens.