{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,27]],"date-time":"2026-08-27T00:03:44Z","timestamp":1787789024279,"version":"build-2784847793"},"reference-count":40,"publisher":"MDPI AG","issue":"8","license":[{"start":{"date-parts":[[2025,7,30]],"date-time":"2025-07-30T00:00:00Z","timestamp":1753833600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Bioengineering"],"abstract":"<jats:p>Background: Gingival recession is a common condition involving apical displacement of the gingival margin, leading to root surface exposure and associated complications such as dentin hypersensitivity and root caries. Among the most effective treatment options are the tunneling technique (TUN) and the coronally advanced flap (CAF), both combined with connective tissue grafts (CTGs). This study aimed to evaluate and compare the clinical outcomes of TUN + CTG and CAF + CTG in terms of root coverage and keratinized tissue width (KTW) over a 6\u201312-month follow-up. Methods: A randomized, double-blind clinical trial was conducted following CONSORT guidelines (ClinicalTrials.gov ID: NCT06228534). Participants were randomly assigned to receive either TUN + CTG or CAF + CTG. Clinical parameters, including gingival recession depth (REC) and KTW, were assessed at baseline as well as 6 months and 12 months postoperatively using a calibrated periodontal probe. Statistical analysis was performed using descriptive statistics and linear mixed models to compare outcomes over time, with a significance level set at 5%. Results: Both techniques demonstrated significant clinical improvements. At 6 months, mean root coverage was 100% in CAF + CTG cases and 97% in TUN + CTG cases, while complete root coverage (REC = 0) was observed in 100% and 89% of cases, respectively. At 12 months, root coverage remained stable, at 99% in the CAF + CTG group and 97% in the TUN + CTG group. KTW increased in both groups, with higher values observed in the CAF + CTG group (3.53 mm vs. 3.11 mm in TUN + CTG at 12 months). No significant postoperative complications were reported. Conclusions: Both TUN + CTG and CAF + CTG are safe and effective techniques for treating RT1 and RT2 gingival recession, offering high percentages of root coverage and increased KTW. While CAF + CTG achieved slightly superior coverage and tissue gain, the TUN was associated with better aesthetic outcomes and faster recovery, making it a valuable alternative in clinical practice.<\/jats:p>","DOI":"10.3390\/bioengineering12080824","type":"journal-article","created":{"date-parts":[[2025,7,30]],"date-time":"2025-07-30T14:00:41Z","timestamp":1753884041000},"page":"824","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":4,"title":["Comparative Effectiveness of Tunneling vs. Coronally Advanced Flap Techniques for Root Coverage: A 6\u201312-Month Randomized Clinical Trial"],"prefix":"10.3390","volume":"12","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-8713-951X","authenticated-orcid":false,"given":"Luis","family":"Chauca-Baja\u00f1a","sequence":"first","affiliation":[{"name":"College Dentistry, University of Guayaquil, Guayas 090101, Ecuador"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Pedro Samuel","family":"V\u00e1squez Gonz\u00e1lez","sequence":"additional","affiliation":[{"name":"Periodontics and Implantology Oral Research, University of Guayaquil, Guayas 090101, Ecuador"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Mar\u00eda Jos\u00e9","family":"Alban Guijarro","sequence":"additional","affiliation":[{"name":"Specialist in Forensic Medicine, University of Guayaquil, Guayas 090101, Ecuador"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Carlos Andr\u00e9s","family":"Guim Mart\u00ednez","sequence":"additional","affiliation":[{"name":"School of Dentistry, Universidad Cat\u00f3lica de Santiago de Guayaquil (UCSG), Guayas 090101, Ecuador"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5660-3941","authenticated-orcid":false,"given":"Byron","family":"Vel\u00e1squez Ron","sequence":"additional","affiliation":[{"name":"Dental Prosthesis Department Research, College Dentistry, University of the Americas, UDLA, Av, Colon y 6 de Diciembre, Campus Col\u00f3n, Quito 170102, Ecuador"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Patricio","family":"Proa\u00f1o Yela","sequence":"additional","affiliation":[{"name":"College Dentistry, University of Guayaquil, Guayas 090101, Ecuador"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9180-4703","authenticated-orcid":false,"given":"Alejandro Ismael","family":"Lorenzo-Pouso","sequence":"additional","affiliation":[{"name":"Oral Medicine, Oral Surgery and Implantology Unit (MedOralRes), Faculty of Medicine and Dentistry, University of Santiago de Compostela, 15782 Santiago de Compostela, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5174-8922","authenticated-orcid":false,"given":"Alba","family":"P\u00e9rez-Jard\u00f3n","sequence":"additional","affiliation":[{"name":"Oral Medicine, Oral Surgery and Implantology Unit (MedOralRes), Faculty of Medicine and Dentistry, University of Santiago de Compostela, 15782 Santiago de Compostela, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Andrea","family":"Ordo\u00f1ez Balladares","sequence":"additional","affiliation":[{"name":"College Dentistry, University of Guayaquil, Guayas 090101, Ecuador"},{"name":"College Dentistry, University Bolivariana del Ecuador, Dur\u00e1n 092406, Ecuador"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2025,7,30]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"178","DOI":"10.1111\/idj.12617","article-title":"Treatment of Gingival Recession: When and How?","volume":"71","author":"Imber","year":"2021","journal-title":"Int. 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