Modified coronally advanced tunnel technique with enamel matrix derivative in addition to subepithelial connective tissue graft compared with connective tissue graft alone for the treatment of multiple gingival recessions: prognostic parameters for clinical treatment outcomes

Objectives To investigate factors that influence 12-month outcomes after treatment of multiple gingival recessions (GR) with modified coronally advanced tunnel (MCAT) and subepithelial connective tissue graft (SCTG) with enamel matrix derivative (EMD) (tests) or without (controls). Materials and methods Twenty patients with 150 GR were treated. Logistic regression models were used to identify baseline parameters that could predict 12-month average root coverage (ARC), complete root coverage (CRC), root esthetic coverage score (RES), gain in keratinized tissue width (KTW), and gain in gingival thickness (GT). Results The likelihood of ARC > 85% increased sevenfold (odds ratio [OR] = 7.33; 95% confidence interval [CI] = 2.43-12.12), of achieving CRC: 21-fold (OR = 21.23; 95% CI = 10.21-45.32), and of gaining RES = 10: tenfold (OR = 10.23; 95% CI = 5.78-32.23) in favor of EMD-treated sites. With each 1-mm(2) increase in baseline avascular exposed root surface area (AERSA), the odds of failure (ARC <= 85%, not achieving CRC and postoperative GT <= 2 mm) increased almost fourfold (OR = 3.56; 95% CI = 1.98-10.19), fourfold (OR = 4.23; 95% CI = 1.11-9.02), and nearly sixfold (OR = 5.76; 95% CI = 2.43-12.87), respectively. The greater the baseline GT, the more likely the chance of achieving CRC (OR = 10.23; 95% CI = 8.37-16.23) and RES = 10 (OR = 5.50; 95% CI = 3.34-16.43). All models exhibited fair to excellent discrimination and satisfactory calibration. Conclusions Based on logistic regression, EMD application improved postoperative ARC, CRC and RES; baseline AERSA predicted 12-month ARC, CRC, and GT gain, whereas baseline GT was a predictor of achieving CRC and perfect RES.