Abstract：
OBJECTIVE: Free gingival graft (FGG) is the most effective way to increase the apico-coronal width of the keratinized mucosa. In case of limited donor tissue, the accordion technique can be used. This study compared FGG for dimensional and clinical changes using accordion and conventional methods.
METHODS: Ninety-four implants with keratinized tissue deficiency (<2 mm) were randomly assigned to treatment with accordion (49 implants) and conventional (45 implants) FGG. Endpoints including apico-coronal keratinized tissue width, vertical shrinkage, vestibular depth, probing depth, bleeding on probing, and plaque index were measured. The graft harvesting and recipient bed preparation method were similar in the two groups, and the only difference was the graft length. FGG was harvested with a length 40% shorter than the mesiodistal length of the recipient area in the accordion method and as much as the recipient area in the conventional method.
RESULTS: vertical graft shrinkage 1, 3, and 6 months following conventional graft placement was 12.04 ± 14.99, 17.12 ± 20.40, and 23.29 ± 24.63 percent, respectively. In the accordion graft group, the shrinkage was significantly greater with 30.10 ± 16.12, 36.99 ± 15.51, and 43.75 ± 18.78 percent at 1, 3, and 6 months, respectively (p-value < .001). Other factors did not show a clinically significant difference between the two groups.
CONCLUSIONS: Comparison of vertical shrinkage changes shows that the shrinkage rate in the accordion group is significantly higher than the conventional group.
BACKGROUND: IRCT20190721044296N1 (Evaluation of dimensional changes of peri-implant attached mucosa following the treatment of free gingival graft by conventional and accordion methods; randomized clinical trial two-arm parallel).
METHODS: Ninety-four implants with keratinized tissue deficiency (<2 mm) were randomly assigned to treatment with accordion (49 implants) and conventional (45 implants) FGG. Endpoints including apico-coronal keratinized tissue width, vertical shrinkage, vestibular depth, probing depth, bleeding on probing, and plaque index were measured. The graft harvesting and recipient bed preparation method were similar in the two groups, and the only difference was the graft length. FGG was harvested with a length 40% shorter than the mesiodistal length of the recipient area in the accordion method and as much as the recipient area in the conventional method.
RESULTS: vertical graft shrinkage 1, 3, and 6 months following conventional graft placement was 12.04 ± 14.99, 17.12 ± 20.40, and 23.29 ± 24.63 percent, respectively. In the accordion graft group, the shrinkage was significantly greater with 30.10 ± 16.12, 36.99 ± 15.51, and 43.75 ± 18.78 percent at 1, 3, and 6 months, respectively (p-value < .001). Other factors did not show a clinically significant difference between the two groups.
CONCLUSIONS: Comparison of vertical shrinkage changes shows that the shrinkage rate in the accordion group is significantly higher than the conventional group.
BACKGROUND: IRCT20190721044296N1 (Evaluation of dimensional changes of peri-implant attached mucosa following the treatment of free gingival graft by conventional and accordion methods; randomized clinical trial two-arm parallel).
摘要：
目的：游离牙龈移植（FGG）是增加角化粘膜冠状宽度的最有效方法。如果供体组织有限，可以使用手风琴技术。本研究使用手风琴和常规方法比较了FGG的尺寸和临床变化。
方法：将94个角化组织缺损（<2mm）的植入物随机分配到手风琴（49个植入物）和常规（45个植入物）FGG治疗中。终点包括冠状角化组织宽度，垂直收缩，前庭深度,探测深度,探查时出血,并测量菌斑指数。两组的移植物收获和受体床准备方法相似，唯一的区别是移植物的长度。在手风琴方法中，FGG的收获长度比受体区域的近端长度短40％，而在常规方法中，FGG的收获长度比受体区域短40％。
结果：常规移植物放置后1、3和6个月的垂直移植物收缩率分别为12.04±14.99、17.12±20.40和23.29±24.63%，分别。在手风琴移植组中，在1、3和6个月时，收缩率明显更大，分别为30.10±16.12、36.99±15.51和43.75±18.78%，分别（p值<.001）。其他因素在两组之间没有显示出临床上的显着差异。
结论：垂直收缩变化的比较表明，手风琴组的收缩率明显高于常规组。
背景：IRCT20190721044296N1（通过常规和手风琴方法治疗游离牙龈移植物后，评估种植体周围附着粘膜的尺寸变化；随机临床试验双臂平行）。
方法：将94个角化组织缺损（<2mm）的植入物随机分配到手风琴（49个植入物）和常规（45个植入物）FGG治疗中。终点包括冠状角化组织宽度，垂直收缩，前庭深度,探测深度,探查时出血,并测量菌斑指数。两组的移植物收获和受体床准备方法相似，唯一的区别是移植物的长度。在手风琴方法中，FGG的收获长度比受体区域的近端长度短40％，而在常规方法中，FGG的收获长度比受体区域短40％。
结果：常规移植物放置后1、3和6个月的垂直移植物收缩率分别为12.04±14.99、17.12±20.40和23.29±24.63%，分别。在手风琴移植组中，在1、3和6个月时，收缩率明显更大，分别为30.10±16.12、36.99±15.51和43.75±18.78%，分别（p值<.001）。其他因素在两组之间没有显示出临床上的显着差异。
结论：垂直收缩变化的比较表明，手风琴组的收缩率明显高于常规组。
背景：IRCT20190721044296N1（通过常规和手风琴方法治疗游离牙龈移植物后，评估种植体周围附着粘膜的尺寸变化；随机临床试验双臂平行）。
