Division of Orthodontics and Dentofacial Deformities, Centre for Dental Education and Research, All India Institute of Medical Sciences, New Delhi, 110029, India.
Dr CG Pandit National Chair of Indian Council of Medical Research, New Delhi, India.
Prog Orthod. 2021 Oct 18;22(1):33. doi: 10.1186/s40510-021-00378-0.
Literature shows that the expression of various biomarkers in peri-miniscrew crevicular fluid (PMICF) is related to the stability of miniscrew implants (MSIs). The present study investigated the role and alterations in levels of circulating cell-free nucleic acids (cfNAs) in PMICF before and after orthodontic loading.
This prospective study consisted of forty-six MSIs placed between the second premolar and first molar in the maxillary and mandibular arches. Direct loading was done after 3 weeks of MSI insertion with nickel-titanium closed coil spring exerting a force of 200 g. The PMICF sample was collected at various time intervals, and the level of cfNA was determined. Clinical parameters, including implant mobility and gingival health, were also assessed. Pre-loading and post-loading parameters were assessed using Wilcoxon's rank-sum test.
Among 46 MSIs, 36 were stable during the study and 10 MSIs showed peri-implant inflammation and increased mobility. There was a significant rise in the cfNA concentration 24 h after implant insertion (0.4 ± 0.86 ng/μl). The level of cfNAs significantly decreased over 3 weeks and reached the baseline level (0.2 ± 0.31 ng/μl). There was also a significant rise in the levels of cfNA (0.8 ± 0.70 ng/μl) at 24 h after loading MSIs, which gradually decreased to 0.2 ± 0.24 ng/μl after 63 days. The expression of cfNAs was on the average 0.32 units more in the cases with failed implants (P = 0.05).
cfNA levels in PMICF showed an upward trend 24 h after MSI insertion and 24 h after orthodontic loading. The expression of cfNA was more in cases with failed MSIs. Hence, the cfNAs can be considered as a prognostic biomarker of MSI stability.
文献表明，各种生物标志物在微螺钉周围龈沟液（PMICF）中的表达与微螺钉植入物（MSI）的稳定性有关。本研究探讨了正畸加载前后 PMICF 中循环无细胞核酸（cfNAs）水平的变化及其作用。
本前瞻性研究共纳入 46 例上颌和下颌第二前磨牙与第一磨牙之间放置的 MSI。在 MSI 插入后 3 周，用镍钛封闭线圈弹簧施加 200g 的力直接加载。在不同时间间隔采集 PMICF 样本，并测定 cfNA 水平。还评估了临床参数，包括种植体动度和牙龈健康状况。使用 Wilcoxon 秩和检验评估加载前和加载后的参数。
在 46 个 MSI 中，36 个在研究期间稳定，10 个 MSI 出现种植体周围炎症和动度增加。植入后 24 小时 cfNA 浓度显著升高（0.4±0.86ng/μl）。3 周后，cfNAs 水平显著下降并达到基线水平（0.2±0.31ng/μl）。加载 MSI 后 24 小时，cfNA 水平也显著升高（0.8±0.70ng/μl），63 天后逐渐降至 0.2±0.24ng/μl。失败植入物的 cfNAs 表达平均高出 0.32 个单位（P=0.05）。
PMICF 中的 cfNA 水平在 MSI 插入后 24 小时和正畸加载后 24 小时呈上升趋势。cfNA 在失败的 MSI 病例中表达更高。因此，cfNAs 可被视为 MSI 稳定性的预后生物标志物。
