At 12months , recession reduction as well as mean root coverage were significantly better at CT-grafted sites treated in the TUN group ( 1.94 mm and 98.4 % respectively ) compared to the non-augmented sites of the CAF group ( 1.17 mm and 71.8 % respectively ) and statistical analysis revealed a positive correlation of THK ( 1.63 mm TUN versus 0.91 mm CAF , p < 0.0001 ) to both these variables .