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Published on: February 10, 2020
Twenty-year results after connective tissue grafts and guided tissue regeneration for root coverage
Hari Petsos1,2, Peter Eickholz1, Petra Ratka-Krüger3
1Department of Periodontology, Center for Dentistry and Oral Medicine (Carolinum), Johann Wolfgang Goethe-University Frankfurt/Main, Frankfurt, Germany.
Background:
Evaluation of clinical long-term results 20 years after connective tissue grafting (CTG) or guided tissue regeneration (GTR) using bioabsorbable barriers for root coverage therapy.
Methods:
Initially, 15 patients with 38 Miller Class I and II recession defects underwent CTG or GTR according to random assignment. At baseline, 3, 120 ± 12, and 240 ± 12 months after surgery, data on probing depth, clinical attachment level, recession depth and width, amount of keratinized tissue, and bleeding on probing were obtained. Additionally, patients' smoking habits and participation in supportive periodontal therapy were investigated.
Results:
Eight patients contributing 23 recessions were available at the 240 ± 12 months follow-up. Three and 120 ± 12 months after therapy with CTG, significantly better root coverage was observed compared with baseline (3 months: 3.01 ± 1.74 mm; P = 0.003; 120 ± 12 months: 2.11 ± 1.86 mm; P < 0.024). GTR resulted in significantly better root coverage compared with baseline after 3 months (2.25 ± 1.89 mm; P < 0.012). Although there were no significant changes in the recession depth between 3 and 240 ± 12 months in both groups (CTG: P = 0.097; GTR: P = 0.190), 1.57 ± 2.12 mm (CTG) and 1.19 ± 2.31 mm (GTR) of the achieved coverage after 3 months were lost. CTG showed significantly better relative root coverage percentage than GTR after 3 (P = 0.026) and 120 (P = 0.038) months. This study failed to detect a significant difference in the stability of root coverage after 240 ± 12 months between CTG and GTR (P = 0.448) and patients' assessments of their treatment outcomes (P = 0.503).
Conclusion:
Long-term stability of root coverage and patient-perceived esthetic outcomes failed to show significant differences between CTG and GTR at 20 years post-surgery.
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