The influence of anatomical features on the outcome of gingival recessions treated with coronally advanced flap and enamel matrix derivative : a 1-year prospective study

Background: Coronally advanced flap (CAF) is one of the most effective treatments of Miller Class I and II recessions. Even if excellent outcomes are reported in the literature, complete root coverage is not always predictable, since many surgical and host-related factors may affect the percentage of root coverage obtained. The aim of this clinical study was to evaluate if some anatomical features such as tissue thickness, papillae height and width, recession depth, and vestibular bone height may influence defect coverage of Miller Class I and II gingival recessions treated with CAF in combination with enamel matrix derivative (EMD). Methods: Thirty healthy, non-smoking patients (13 men and 17 women; mean age 32.8 (plus or minus) 6.2 years) were enrolled. Each patient was treated for one single recession using a CAF with the adjunct of EMD. Clinical parameters at baseline and 6 and 12 months were recorded and compared by using paired Student t test. Data were subdivided in two groups according to the baseline recession depth (REC): REC <4 mm (group 1) and REC (greater-than or equal to)4 mm (group 2). The relation between the anatomical parameters (papilla height, papilla width, crestal bone height, and flap thickness) and percent of root coverage was evaluated by multiple linear regression analysis. Results: At 12 months, 91.7% of root coverage was obtained with a mean attachment gain of 3.23 mm. Better results in terms of percentage of root coverage were obtained when the baseline REC was <4 mm compared to defects (greater-than or equal to)4 mm (96.5% versus 83.5%). Flap thickness was positively correlated to the percentage of root coverage. For gingival recessions (greater-than or equal to)4 mm, 100% root coverage was achieved only when tissue thickness was (greater-than or equal to)1 mm. Root coverage percentage was slightly related to papilla width in both groups, while it was associated with papilla height only in group 1 (P= 0.004). Only in patients in group 1 was the height of bone on the vestibular side related to the percentage of root coverage obtained (P= 0.003). Conclusions: The results of the present study suggest that baseline recession depth and flap thickness may influence the outcome of marginal tissue recession therapy with CAF plus EMD at 12 months. There is not a clear relation between root coverage and other anatomical features as papilla width, papilla height, and the amount of bone on the vestibular side.