Background: Connective tissue grafts (CTGs) and coronally advanced flaps (CAFs) do not regenerate periodontal attachment apparatus when used to treat gingival recessions (GRs). Instead of generating new bone, cementum, and inserting periodontal ligament fibers, CTG+CAF repairs through a long epithelial junction and connective tissue attachment. Enamel matrix derivatives (EMDs) have demonstrated proof-of-principle that periodontal regeneration can be achieved, although data are limited.
Methods: Three patients, each requiring extraction of four premolars before orthodontic treatment, were enrolled in a randomized, open-label study. Two months after induction of Miller Class I and II GR, each patient received EMD+CAF for three teeth and CTG+CAF for one tooth for root coverage. Nine months after root coverage, all four premolars from each of the three patients were surgically extracted en bloc for histologic and microcomputed tomography (micro-CT) analysis, looking for evidence of periodontal regeneration. Standard clinical measurements, radiographs, and intraoral photographs were taken over prescribed time points.
Results: Seven of the nine teeth treated with EMD+CAF demonstrated varying degrees of periodontal regeneration, detailed through histology with new bone, cementum, and inserting fibers. Micro-CT corroborated these findings. None of the three teeth treated with CTG+CAF showed periodontal regeneration. Clinical measurements were comparable for both treatments. One instance of root resorption and ankylosis was noted with EMD+CAF.
Conclusions: EMD+CAF continues to show histologic evidence of periodontal regeneration via human histology, this being the largest study (nine teeth) examining its effect when treating GR. The mechanism of action, ideal patient profile, and criteria leading to predictable regeneration are in need of further exploration.
Keywords: Alveolar bone; biomimetics; dental cementum; gingival recession; histology; periodontal regeneration.