RESUMEN
The present study was designed to evaluate the healing process of gingival recession defects treated with enamel matrix derivative [EMD] and to compare it to that obtained with 24% ethylenediamine tetra acetic acid [EDTA] and the laterally repositioned flapsalone. Gingival recessions were surgically created on the buccal surfaces of maxillary canines and fourth premolars and mandibular first molars of eight beagle dogs. Plaquewas allowed to accumulate for five weeks. Following apreparation period, the defects were randomly assigned to one of the three treatment groups [EMD, EDTA, and control groups]. Four dogs each were sacrificed at three and six months post-treatment. Clinical parameters which included the gingival recession depth and width were measured, and the length of the total epithelium and connective tissue attachment were histometrically evaluated. All three treatments resulted in a statistically significant decrease of the gingival recession depthand width when compared to the baseline [P < 0.05]. Three and six months following surgery, EMD and EDTA groups demonstrated significantly higher percentage of root coverage when compared to the control group. There was no statistically significant difference in the percentage of root coverage between EMD and EDTA groups. Histologically, all three treatment groups demonstrated a new connective tissue attachment. Histometrically, EMD treated sites showed a statistically significant increase of new connective tissue attachment when compared to the EDTA treated sites and controls at three and six months [P < 0.05]. The epithelium length was similar in the EMD and EDTA treated sites [P > 0.05] and it was significantly shorterin the EMD group when compared to the control group [P < 0.05] at three and six months. There were no statistically significant differences between the EDTA and control groups in the length of the epithelium and connective tissue attachment. EMD seemed to significantly improve the clinical and histological outcomes of gingival recessions treated by means of the laterally repositioned flapsurgery