Liñares Antonio, Tan Hong Jin, Muñoz Fernando, Rakasevic Dragana, Leira Yago, Blanco Juan
Periodontology Unit, Faculty of Odontology, University of Santiago de Compostela and Medical-Surgical Dentistry Research Group (GI-2117), Health Research Institute of Santiago de Compostela, Santiago de Compostela, Spain.
Periodontology Unit, Eastman Dental Institute, University College London, London, UK.
J Clin Periodontol. 2025 Jun;52(6):920-928. doi: 10.1111/jcpe.14140. Epub 2025 Apr 15.
To evaluate early buccal bone resorption (BBR) in areas with or without buccal keratinized tissue (KT), and different mucosal thickness (MT) following implant placement at healed sites.
In 9 beagle dogs, three months following the hemimaxilla third and fourth premolars extraction, full-thickness flaps were elevated and two tissue-level implants were inserted. Before suturing, each dog was randomly assigned into 3 groups (control, non-keratinized tissue, NKT and non-keratinized tissue plus connective tissue graft, NKT-CTG). In both experimental groups (NKT and NKT-CTG), buccal KT was excised. In the NKT-CTG group, a CTG was sutured to the buccal alveolar mucosa flap (BF) and coronally repositioned around the implant neck, while in the NKT group, only the BF was repositioned. BF with a 2 mm KT band was repositioned around the implants in the control group. Buccal bone thickness (BBT), MT and KT width were measured clinically at baseline. Three months later, BBR and MT were analysed histologically.
Mucosal thickness at surgery was similar in NKT and control groups (1.33 ± 0.26 mm and 1.67 ± 0.52 mm, respectively). In the NKT-CTG group, MT was 2.50 ± 0.45. The mean BBT measured at the mid-buccal region was about 1 mm in the 3 groups. Three months later, early BBR was observed in all groups, with mean values of 0.91 mm ± 0.62 (control), 1.11 mm ± 0.69 (NKT) and 1.10 mm ± 0.58 (NKT-CTG). The mean values of MT at a 1.5 mm distance from the marginal mucosa were 1.20 mm ± 0.69 (control), 2.18 mm ± 0.53 (NKT) and 3.45 mm ± 1.33 (NKT-CTG).
Within the limitations of the present investigation, the presence or absence of KT did not affect early BBR. CTG placed in the zones without KT did not prevent early BBR.
评估在愈合部位植入种植体后，有或无颊侧角化组织（KT）以及不同黏膜厚度（MT）区域的早期颊侧骨吸收（BBR）情况。
在9只比格犬中，上颌第三和第四前磨牙拔除3个月后，掀起全厚瓣并植入两枚组织水平种植体。缝合前，每只犬被随机分为3组（对照组、非角化组织组，NKT组和非角化组织加结缔组织移植组，NKT - CTG组）。在两个实验组（NKT组和NKT - CTG组）中，切除颊侧KT。在NKT - CTG组中，将结缔组织移植片缝合到颊侧牙槽黏膜瓣（BF）上，并围绕种植体颈部进行冠向复位，而在NKT组中，仅对BF进行复位。对照组在种植体周围复位带有2mm KT带的BF。在基线时临床测量颊侧骨厚度（BBT）、MT和KT宽度。3个月后，组织学分析BBR和MT。
NKT组和对照组手术时的黏膜厚度相似（分别为1.33±0.26mm和1.67±0.52mm）。在NKT - CTG组中，MT为2.50±0.45。3组在颊侧中部区域测量的平均BBT约为1mm。3个月后，所有组均观察到早期BBR，平均值分别为0.91mm±0.62（对照组）、1.11mm±0.69（NKT组）和1.10mm±0.58（NKT - CTG组）。距边缘黏膜1.5mm处MT的平均值分别为1.20mm±0.69（对照组）、2.18mm±0.53（NKT组）和3.45mm±1.33（NKT - CTG组）。
在本研究的局限性范围内，KT的有无不影响早期BBR。在无KT区域植入结缔组织移植片并不能防止早期BBR。
