Mirhashemi Amir Hossein, Akhoundi Mohammad Sadegh Ahmad, Ghazanfari Rezvaneh, Etemad-Moghadam Shahroo, Alaeddini Mojgan, Khorshidian Azam, Dehpour Ahmad Reza, Momeni Nafiseh
Associate Professor, Dental Research Center, Dentistry Research Institute, Tehran University of Medical Sciences, Tehran, Iran; Department of Orthodontics, School of Dentistry, Tehran University of Medical Sciences, Tehran, Iran.
Professor, Laser Research Center, Dentistry Research Institute, Tehran University of Medical Sciences, Tehran, Iran; Department of Orthodontics, School of Dentistry, Tehran University of Medical Sciences, Tehran, Iran.
J Dent (Tehran). 2016 Nov;13(6):388-393.
Nitric oxide (NO) is a signaling molecule that mediates mechanical bone loading. Cyclic guanosine 3', 5' monophosphate (cGMP) is a NO-induced effector molecule. The aim of this study was to assess the effect of NO-cGMP pathway on orthodontic tooth movement (OTM) in rats by use of two phosphodiesterase 5 (PDE5) inhibitors namely sildenafil and tadalafil as chemical tools.
Forty-five male Wistar rats were divided into three equal groups (n=15) based on the substance they received. The first group received daily injections of tadalafil; the second group received daily injections of sildenafil and the third group received daily injections of normal saline. The orthodontic appliances consisted of nickel-titanium closed-coil spring ligated between the maxillary right incisor and the first molar of the animals for 21 days. The amount of tooth movement was measured in all three groups at the end of this period. Histological analysis was performed to assess root resorption lacunae, osteoclast number and periodontal ligament (PDL) thickness.
All appliance-treated molars in the experimental and control groups showed evidence of tooth movement. The mean OTM was calculated to be 0.39±0.16, 0.32±0.16 and 0.26±0.16mm in tadalafil, sildenafil and control groups, respectively and there were no significant differences in OTM among the study groups (P>0.05). In the tadalafil group, significantly greater root resorption on the tension side was seen when compared with controls (P≤0.05).
Tadalafil and sildenafil PDE-5 inhibitors affecting the NO-cGMP pathway did not affect OTM in rats.
一氧化氮（NO）是一种介导机械性骨负荷的信号分子。环磷酸鸟苷（cGMP）是一种由NO诱导产生的效应分子。本研究旨在使用两种磷酸二酯酶5（PDE5）抑制剂西地那非和他达拉非作为化学工具，评估NO-cGMP通路对大鼠正畸牙移动（OTM）的影响。
45只雄性Wistar大鼠根据所接受的物质分为三组，每组15只。第一组每日注射他达拉非；第二组每日注射西地那非；第三组每日注射生理盐水。正畸矫治器由镍钛闭合回形弹簧组成，结扎在动物上颌右侧切牙和第一磨牙之间，持续21天。在此期间结束时，测量三组的牙齿移动量。进行组织学分析以评估牙根吸收陷窝、破骨细胞数量和牙周膜（PDL）厚度。
实验组和对照组中所有接受矫治器处理的磨牙均显示出牙齿移动的迹象。他达拉非组、西地那非组和对照组的平均OTM分别计算为0.39±0.16、0.32±0.16和0.26±0.16mm，研究组之间的OTM无显著差异（P>0.05）。与对照组相比，他达拉非组张力侧的牙根吸收明显更严重（P≤0.05）。
影响NO-cGMP通路的他达拉非和西地那非PDE-5抑制剂不影响大鼠的OTM。
