Acharya Aditya, Lekha K P, Chodankar Raisa, Alpesh Zawar Yash, Patil Konark, Rao Adithi
Department of Prosthodontics, KLE Academy of Higher Education and Research, Deemed-to-be-University, Belagavi, Karnataka, India.
Department of Prosthodontics, SDM College and Hospital, Dharwad, Karnataka, India.
J Oral Biol Craniofac Res. 2025 Sep-Oct;15(5):1103-1107. doi: 10.1016/j.jobcr.2025.07.016. Epub 2025 Jul 26.
Every tooth in the arch and the soft tissues around the prepared tooth need to be replicated in the impression. To prevent tearing during impression removal, it is essential to ensure sufficient sulcus width. To date, mechanical, chemico-mechanical, electrosurgical, surgical, and laser methods have been used to accomplish gingival retraction. The purpose of both clinical and laboratory analysis of the efficacies of chemically impregnated retraction cord and polyvinyl siloxane foam retraction systems is based on the relative amount of vertical and horizontal gingival displacement, time of placement, and the presence or absence of bleeding.
A total of 30 participants aged 20-40 years were enrolled in a randomized controlled trial and quality assessment was conducted according to the CONSORT checklist (CTRI/2022/10/046181). In a split-mouth design, retraction was done using 25 % aluminium sulfate-impregnated retraction cords and Magic FoamCord (MFC). The Mann-Whitney and T-tests were used for data analysis.
Mann-Whitney Test concluded that for vertical gingival retraction cord and Magic foam at 2nd M are statistically insignificant in all three sites (p > 0.05). The mean horizontal displacement achieved at the second molar and second premolar for retraction cord was 0.36 ± 0.07 mm, which was greater than MFC, 0.24 ± 0.06 mm (p = 0.001; 95 % CI). The T-test used for the time of placement between retraction cord and magic foam cord was significant (p < 0.001). The gingiva was observed for presence or absence of bleeding soon after retrieval of the retraction cord and the MFC.
Retraction cords provide greater horizontal displacement but are more time-consuming and traumatic compared to MFC, which is more time-efficient and less invasive. This highlights the need to balance efficacy and efficiency in clinical practice.
牙弓中的每颗牙齿以及预备牙周围的软组织都需要在印模中复制出来。为防止取印模时撕裂，确保足够的龈沟宽度至关重要。迄今为止，已使用机械、化学机械、电外科、外科和激光方法来实现牙龈退缩。对化学浸渍退缩线和聚硅氧烷泡沫退缩系统的疗效进行临床和实验室分析的目的，是基于垂直和水平牙龈移位的相对量、放置时间以及有无出血情况。
共有30名年龄在20至40岁之间的参与者被纳入一项随机对照试验，并根据CONSORT清单（CTRI/2022/10/046181）进行质量评估。采用分口设计，使用25%硫酸铝浸渍退缩线和魔术泡沫线（MFC）进行退缩。数据分析采用曼-惠特尼检验和T检验。
曼-惠特尼检验得出，在所有三个部位，第二磨牙处垂直牙龈退缩线和魔术泡沫在统计学上均无显著差异（p>0.05）。退缩线在第二磨牙和第二前磨牙处实现的平均水平位移为0.36±0.07毫米，大于MFC的0.24±0.06毫米（p = 0.001；95%置信区间）。用于比较退缩线和魔术泡沫线放置时间的T检验具有显著性（p<0.001）。在取出退缩线和MFC后，立即观察牙龈有无出血情况。
退缩线提供更大的水平位移，但与MFC相比更耗时且创伤更大，MFC更省时且侵入性更小。这凸显了在临床实践中平衡疗效和效率的必要性。
