Clinical Outcomes After Treatment of Non‐Contained Intrabony Defects With Enamel Matrix Derivative or Guided Tissue Regeneration: A 12‐Month Randomized Controlled Clinical Trial

Background: The purpose of this study is to compare the healing of deep, non‐contained intrabony defects (i.e., with a ≥80% 1‐wall component and a residual 2‐ to 3‐wall component in the most apical part) treated with either an enamel matrix derivative (EMD) or guided tissue regeneration (GTR) after 12 months. Methods: In this randomized, controlled clinical trial, 40 subjects with 40 defects affecting single‐rooted teeth were treated. The defects were treated with EMD alone or with a non‐resorbable titanium‐reinforced membrane. No grafting materials were used. At baseline and after 12 months, clinical parameters including probing depths (PDs) and clinical attachment levels (CAL) were recorded. The difference in CAL gain was the primary outcome. Results: At baseline, the intrabony component of the defects amounted to 8.5 ± 2.2 mm at EMD‐treated sites and 8.6 ± 1.7 mm at GTR‐treated sites (P = 0.47). The mean CAL gain at sites treated with GTR was significantly greater (P <0.001) than that at sites treated with EMD (4.1 ± 1.4 mm versus 2.4 ± 2.2 mm, respectively). GTR therapy, compared to EMD application alone, significantly (P = 0.01) increased the probability of CAL gain ≥4 mm (79.2% versus 11.3%, respectively) and significantly (P = 0.01) decreased the probability of residual PDs ≥6 mm (3% versus 79.3%, respectively). Conclusion: Although the outcomes of open‐flap debridement alone were not investigated, the application of EMD alone appeared to yield less PD reduction and CAL gain compared to GTR therapy in the treatment of deep, non‐contained intrabony defects.