RESUMO
国家自然科学基金项目(11932012、81400536),上海申康医院发展中心临床创新三年行动计划(SHDC2020CR3009A),上海交通大学医工(理)交叉基金(JYJC202130)
RESUMO
Objective@#To investgate the effect of Herbst appliance on the growth and remodeling of the temporomandibular joint (TMJ) in class Ⅱ patients with mandibular retrusion by using MRI.@*Methods@#Between December 2010 and October 2014, 12 class Ⅱ patients (11-16 years old) with mandibular retrusion were chosen. The patients were divided into two groups. The control group included 7 patients (14 joints) with normal disc condyle relationship and the anterior disc displacement (ADD) group included 5 patients (10 joints) with anterior disc displacement. The MRI images of TMJ were measured, including condylar height, joint space index and disc position ratio, before and after the treatment.@*Results@#The condylar height of the patients in the control group was significantly increased (P<0.001) after treatment, and no significant difference in joint space index (P=0.821) and disc position ratio (P=0.146) was found. The joint space index of the patients ([-14.70±8.82]% and [4.90±11.35]%) in ADD group changed significantly (P<0.001) after treatment, and no significant difference in condylar height (P=0.294) and disc position ratio (P=0.120) was found.@*Conclusions@#The normal disc condyle relationship was beneficial to the reconstruction of the condylar process, and the increase of the condylar height. The condyle moved forward in patients with anterior disc displacement after treatment.
RESUMO
<p><b>OBJECTIVE</b>To test the hypothesis that the CCL2/CCR2 signaling pathway plays an important role in pain induced by experimental tooth movement.</p><p><b>METHODS</b>Male Sprague- Dawley rats weighing between 200 and 300 g were used in this study. Expression of CCL2/CCR2 in the trigeminal ganglion (TG) was determined by Western blotting 0 h, 4 h, 1 d, 3 d, 5 d, 7 d after tooth movement. Localization of the CCL2 was revealed by immunohistochemistry. Changes in body weight, nocifensive behaviors, and the effects of CCL2/CCR2 antagonists on these changes in pain behaviors were evaluated. Exogenous CCL2 was injected into periodontal tissues and added to TG neurons in culture and the resulting c-fos expression and pain responses were detected. In addition, the expression and cellular localization of CCL2 in the medullary dorsal horn (MDH) was determined by immunohistochemistry 3 d and 14 d after tooth movement.</p><p><b>RESULTS</b>Experimental tooth movement led to a statistically significant increase in CCL2/CCR2 expression at the protein level from day 3 to 7 after application of force initiating tooth movement.When compared with control group (1.000 ± 0.000), CCL2 increased to (2.620 ± 0.128), (3.300 ± 0.197) and (1.740 ± 1.290) at day 3, 5 and 7 respectively, which were statistically significant (P < 0.05). CCR2 expression levels were (1.636 ± 0.061) and (1.766 ± 0.126) compared with that in control group (1.000 ± 0.000) at day 3 and 5 respectively with statistical significance (P < 0.05). Both of them peaked on day 5 (3.3 and 1.8 time compared to control group). Application of recombinant CCL2 led to the up-regulation of c-fos expression in vivo and in vitro, and triggered a corresponding nocifensive behavior in rats. The magnitude of the nocifensive behavior could be reduced by a CCR2 antagonist, and by CCL2 neutralizing antibody. Furthermore, we found a significant increase in the expression of CCL2, corresponding well to the up-regulation of the time spent on nocifensive behaviors after ETM. In addition, CCL2 was up-regulated in TG neurons and astrocytes in Vc.</p><p><b>CONCLUSIONS</b>The CCL2/CCR2 axis was modulated by experimental tooth movement and involved in the development of tooth movement pain, and thus palyed an important role in orthodontic pain mechanism.</p>