Changes in gingival dimensions following connective tissue grafts for root coverage: comparison of two procedures

The purpose of this study was to investigate the changes in gingival dimensions and root coverage using the same surgical procedure but varying the amount of the connective tissue graft left uncovered.

Twenty-five Class I or II recession defects in 20 healthy subjects were randomly assigned to test (exposed connective tissue group; E group) or control (fully covered connective tissue group; FC group) groups and treated with a connective tissue graft procedure. In the E group, 1 to 2 mm of the graft was left uncovered at the completion of the surgery, whereas the FC group had the graft completely covered by the flap. Clinical parameters assessed included probing depth, recession depth, clinical attachment level, width of keratinized tissue, mobility, and plaque score.

At 12 weeks, the mean root coverage percentages for FC and E groups were 93% and 88%, respectively. The difference between the groups was not statistically significant (P=0.48). Complete root coverage was observed in 79% and 64% of the subjects in FC and E groups, respectively. There was greater increase in the width of keratinized tissue in the E group (1.5+/-1.1 mm) than the FC group (0.9+/-0.9 mm), although this difference did not reach statistical significance (P=0.16). There were no statistically significant differences between the groups for the changes in other parameters.

Both procedures resulted in successful root coverage with an increase in the width of keratinized tissue. Leaving a portion of the graft exposed resulted in a greater increase of keratinized tissue, and complete coverage of the graft resulted in greater root coverage. However, these differences did not reach statistical significance.