Coronally Advanced Flap Procedure for Root Coverage. Flap With Tension Versus Flap Without Tension: A Randomized Controlled Clinical Study

Abstract
This clinical controlled study was designed to measure the tension of coronally advanced flaps (CAF) performed to treat shallow gingival recessions and to compare the recession reduction (Rec Red) achieved in a test group (flaps with tension) and in a control group (flaps without tension) 3 months after surgery. Eleven patients, aged 22 to 41 years, with high levels of oral hygiene (full mouth plaque score <20%) were selected for the study. Each patient showed 2 bilateral Miller Class I maxillary or mandibular gingival recessions located on homologous teeth. A total of 22 recessions were treated. The recession depth at the right site was similar to that at the left site (difference < or =1 mm). For each patient, the 2 recessions underwent CAF procedure in the same surgical session. Before suturing, the residual tension (FTens) of both right and left flaps was measured with a dynamometer. Then, one site was randomly assigned to the test group and the contralateral site to the control group. In the test site the flap was sutured. In the control site the flap was further relaxed, the tension was measured again, and the flap was sutured. In the test group (with tension) the initial mean recession depth was 2.82 +/- 0.64 mm and mean FTens was 6.5 g, while in the control group (without tension) the initial mean recession depth was 2.68 +/- 0.81 mm and mean FTens was 0.4 g. Three months later, the test group showed a mean recession reduction of 2.18 +/- 0.60 mm, a mean percent root coverage of 78 +/- 15%, and complete root coverage was achieved on 2 teeth (18%). In the control group the mean recession reduction was 2.32 +/- 0.81 mm and mean percent root coverage was 87 +/- 13%. Complete root coverage was obtained on 5 teeth (45%). The difference of recession reduction between the test and control group was not statistically significant (P = 0.3911). In the test group, linear regression analysis showed a statistically significant association between recession reduction and both recession depth at baseline (P= 0.0001) and mean of the 3 tensions recorded on the test side (MFTens) (P = 0.0009). This study shows that minimal flap tension does not influence recession reduction after 3 months when shallow recessions are treated by means of CAF. In the test group (with tension), the statistical analysis suggests that the higher the flap tension, the lower the recession reduction.