Alsilq Mohamed Najati, Youssef Mohamed
Department of Orthodontics, Faculty of Dentistry, University of Damascus, Al-Mazzeh St, PO Box 30612, Damascus, Syria.
Department of Orthodontics, Faculty of Dentistry, University of Damascus, Damascus, Syria.
Sci Rep. 2025 Jan 13;15(1):1879. doi: 10.1038/s41598-025-86219-0.
Twin block appliances are commonly used to treat skeletal class II malocclusion. However, many adverse effects, such as lower incisor protrusion and a bulky nature, can be observed. To overcome these effects, a modified twin block was designed, which uses vacuum-formed hard plates (VFPs) instead of acrylic plates. This clinical trial evaluated the skeletal and dentoalveolar changes resulting from a modified twin block (aesthetic twin block) (ATB) in comparison with conventional twin block (CTB) in addition to levels of esthetics and discomfort. A two-arm parallel group randomized clinical trial was performed at the Department of Orthodontics, University of Damascus, Syria. Fifty-two patients (33 females and 19 males) aged 12.23 ± 0.77 years with skeletal class II division 1 malocclusion caused by mandibular retrognathism were included. The participants were randomly assigned to a study group according to a simple randomization method using a numbered and sealed envelope. The experimental group was treated with an aesthetic twin block, and the control group was treated with a conventional twin block. Sixteen angular variables and eleven seventeen linear variables (measured in millimeters) were evaluated before the treatment (T0) and at the end of the active phase of the treatment (T1) on lateral cephalometric radiographs and dental casts to study the skeletal and dentoalveolar changes, and a questionnaire was used to assess the levels of esthetic and discomfort. There was a statistically significant change in the ANB angle between the ATB group (-2.70 ± 0.84) and the CTB group (-1.92 ± 0.81°) (P = 0·002) and between the SNB angle of the ATB group (2.72 ± 1.54°) and the CTB group (1.72 ± 1.41°) (P = 0·02). The Jarabak ratio decreased significantly in the CTB group (-0.65 ± 1.37%) (P = 0.02) and increased significantly in the ATB group (0.84 ± 1.44%) (P = 0.007), with significant differences between the two groups (P = 0.000). The change in upper incisor angulation was statistically significant (-1.88 ± 1.48°) for the ATB group and (-3.5 ± 4.18°) for the CTB group (P = 0·001). The change in lower incisor angulation was 1.34 ± 2.08° for the ATB group and 3.88 ± 2.47° for the CTB group, which was statistically significant (P = 0·000). ATB had more control of vertical growth, lower incisor and upper incisor angulation and was more aesthetically acceptable.Trial registration: (NCT05418413) (14/06/2022).
双阻板矫治器常用于治疗骨性II类错牙合畸形。然而，可以观察到许多不良反应，如下前牙前突和体积较大。为了克服这些影响，设计了一种改良双阻板，它使用真空成型硬板（VFP）代替丙烯酸板。本临床试验评估了改良双阻板（美学双阻板）（ATB）与传统双阻板（CTB）相比所导致的骨骼和牙牙槽变化，以及美学和不适程度。在叙利亚大马士革大学正畸科进行了一项双臂平行组随机临床试验。纳入了52例年龄为12.23±0.77岁、因下颌后缩导致骨性II类1分类错牙合畸形的患者（33例女性和19例男性）。参与者通过使用编号并密封的信封的简单随机化方法随机分配到研究组。实验组采用美学双阻板治疗，对照组采用传统双阻板治疗。在治疗前（T0）和治疗活跃期结束时（T1），在头颅侧位片和石膏模型上评估16个角度变量和11个线性变量（以毫米为单位测量），以研究骨骼和牙牙槽变化，并使用问卷评估美学和不适程度。ATB组（-2.70±0.84）和CTB组（-1.92±0.81°）之间的ANB角有统计学显著变化（P = 0.002），ATB组（2.72±1.54°）和CTB组（1.72±1.41°）的SNB角之间也有统计学显著变化（P = 0.02）。Jarabak比率在CTB组显著降低（-百分之0.65±1.37）（P = 0.02），在ATB组显著升高（百分之0.84±1.44）（P = 0.007），两组之间有显著差异（P = 0.000）。ATB组上前牙角度变化有统计学显著意义（-1.88±1.48°），CTB组为（-3.5±4.18°）（P = 0.001）。ATB组下前牙角度变化为1.
