Abstract：
OBJECTIVE: The objective of this study was to analyze the impact of the abutment width on early marginal bone loss (MBL).
METHODS: A balanced, randomized, double-blind clinical trial with two parallel experimental arms was conducted without a control group. The arms were \"cylindrical\" abutment and \"concave\" abutment. Eighty hexagonal internal connection implants, each with a diameter of 4 × 10 mm, were placed in healed mature bone. The main variable was the peri-implant tissue stability, which was measured as MBL at 8 weeks and 6 months.
RESULTS: The final sample consisted of 77 implants that were placed in 25 patients. 38 (49.4%) were placed using the cylindrical abutment, and the other 39 (50.6%) were placed using the concave abutment. The early global MBL of -0.6 ± 0.7 mm in the cylindrical abutment group was significantly higher than it was in the concave abutment group, in which the early global MBL was -0.4 ± 0.6 mm (p = .030). The estimated effect size (ES) was negative for the cylindrical abutment (ES = -1.3730, CI -2.5919 to -0.1327; t-value = -2.4893; p = .0139), therefore implying a loss of mean bone level, and it was positive for the concave abutment (ES = 2.8231; CI: 1.4379 to 4.2083; t-value = 4.0957; p = .0002), therefore implying an increase in the average bone level.
CONCLUSIONS: The concave abutments presented significantly less early MBL at 6 months post-loading than classical cylindrical abutments did.
METHODS: A balanced, randomized, double-blind clinical trial with two parallel experimental arms was conducted without a control group. The arms were \"cylindrical\" abutment and \"concave\" abutment. Eighty hexagonal internal connection implants, each with a diameter of 4 × 10 mm, were placed in healed mature bone. The main variable was the peri-implant tissue stability, which was measured as MBL at 8 weeks and 6 months.
RESULTS: The final sample consisted of 77 implants that were placed in 25 patients. 38 (49.4%) were placed using the cylindrical abutment, and the other 39 (50.6%) were placed using the concave abutment. The early global MBL of -0.6 ± 0.7 mm in the cylindrical abutment group was significantly higher than it was in the concave abutment group, in which the early global MBL was -0.4 ± 0.6 mm (p = .030). The estimated effect size (ES) was negative for the cylindrical abutment (ES = -1.3730, CI -2.5919 to -0.1327; t-value = -2.4893; p = .0139), therefore implying a loss of mean bone level, and it was positive for the concave abutment (ES = 2.8231; CI: 1.4379 to 4.2083; t-value = 4.0957; p = .0002), therefore implying an increase in the average bone level.
CONCLUSIONS: The concave abutments presented significantly less early MBL at 6 months post-loading than classical cylindrical abutments did.
摘要：
目的：本研究的目的是分析基台宽度对早期边缘骨丢失（MBL）的影响。
方法：平衡，随机化，在没有对照组的情况下,采用两个平行实验组进行双盲临床试验.臂为“圆柱形”基台和“凹形”基台。八十个内六角连接植入物，每个直径为4×10毫米，被放置在愈合的成熟骨中。主要变量是种植体周围组织的稳定性，在8周和6个月时测量为MBL。
结果：最终样品由放置在25名患者中的77个植入物组成。38（49.4%）使用圆柱形基台放置，和其他39（50.6％）使用凹基台放置。圆柱形基牙组的早期整体MBL为-0.6±0.7mm，明显高于凹形基牙组，其中早期全球MBL为-0.4±0.6mm(p=.030)。圆柱形基台的估计效应大小（ES）为负（ES=-1.3730，CI-2.5919至-0.1327；t值=-2.4893；p=.0139），因此意味着平均骨骼水平的损失，并且对凹基台为正（ES=2.8231；CI：1.4379至4.2083；t值=4.0957；p=.0002），因此意味着平均骨骼水平的增加。
结论：在加载后6个月，凹面基台的早期MBL明显少于经典的圆柱形基台。
方法：平衡，随机化，在没有对照组的情况下,采用两个平行实验组进行双盲临床试验.臂为“圆柱形”基台和“凹形”基台。八十个内六角连接植入物，每个直径为4×10毫米，被放置在愈合的成熟骨中。主要变量是种植体周围组织的稳定性，在8周和6个月时测量为MBL。
结果：最终样品由放置在25名患者中的77个植入物组成。38（49.4%）使用圆柱形基台放置，和其他39（50.6％）使用凹基台放置。圆柱形基牙组的早期整体MBL为-0.6±0.7mm，明显高于凹形基牙组，其中早期全球MBL为-0.4±0.6mm(p=.030)。圆柱形基台的估计效应大小（ES）为负（ES=-1.3730，CI-2.5919至-0.1327；t值=-2.4893；p=.0139），因此意味着平均骨骼水平的损失，并且对凹基台为正（ES=2.8231；CI：1.4379至4.2083；t值=4.0957；p=.0002），因此意味着平均骨骼水平的增加。
结论：在加载后6个月，凹面基台的早期MBL明显少于经典的圆柱形基台。
