The effect of enamel matrix protein on gingival tissue thickness in vivo.

The enamel matrix derivative (EMD) has been used extensively as an adjunct to root coverage procedures to achieve periodontal regeneration. However, its effect on gingival tissues has not been elucidated. The aim of this investigation was to evaluate histometrically the change in gingival soft tissue thickness around dehiscence-type defects treated with EMD. Five adult female beagle dogs were used. Buccal osseous dehiscences were surgically created on the maxillary canines and the second and fourth premolars. Thirty defect sites were randomly assigned to test and control groups (15 defect sites for each group). The test group received EMD application, whereas the control group did not. After 4 months of healing, the dogs were killed and tissue blocks were prepared. Histometric analysis showed that the mean thickness of gingival tissue was 1.76 ± 0.23 mm in EMD-treated sites compared to 0.72 ± 0.11 mm for control sites. The difference between the test and control groups was statistically significant (P < 0.0001). It appears that EMD has a positive influence on the increase in gingival tissue thickness when used in dehiscence-type defects in the beagle dog.