Department of Orthodontics, School of Dentistry, University of Geneva, Geneva, Switzerland.
Orthod Craniofac Res. 2013 Feb;16(1):20-7. doi: 10.1111/ocr.12000. Epub 2012 Sep 17.
The dental follicle plays an important role in tooth eruption by providing key regulators of osteogenesis and bone resorption. Patients with cleidocranial dysplasia (CCD) exhibit delayed tooth eruption in combination with increased bone density in the maxilla and mandible, suggesting disturbances in bone remodeling. The aim of this study was to determine the expression of genes relevant for tooth eruption and bone remodeling in the dental follicles of patients with CCD and normal subjects.
Thirteen dental follicles were isolated from five unrelated patients with CCD, and fourteen dental follicles were obtained from 10 healthy individuals. All teeth were in the intraosseous phase of eruption. The expression of RANK, RANKL, OPG, and CSF-1 was determined by quantitative RT-PCR.
In patients with CCD, the mRNA levels of RANK, OPG, and CSF-1 were significantly elevated compared with the control group. Accordingly, the ratios of RANKL/OPG and RANKL/RANK mRNAs were significantly decreased in patients with CCD.
The observed alterations in the expression and ratios of the aforementioned factors in the dental follicle of CCD individuals suggest a disturbed paracrine signaling for bone remodeling that could be responsible for the impaired tooth eruption seen in these patients.
齿槽突在牙齿萌出过程中起着重要作用，为成骨和骨吸收提供关键调节因子。患有颅锁骨发育不全症（CCD）的患者表现出牙齿萌出延迟，同时上颌骨和下颌骨骨密度增加，这表明骨重塑存在紊乱。本研究旨在确定 CCD 患者和正常个体的齿槽突中与牙齿萌出和骨重塑相关的基因表达。
从 5 名无关 CCD 患者中分离出 13 个齿槽突，从 10 名健康个体中获得 14 个齿槽突。所有牙齿均处于萌入骨内阶段。通过定量 RT-PCR 测定 RANK、RANKL、OPG 和 CSF-1 的表达。
与对照组相比，CCD 患者的 RANK、OPG 和 CSF-1 mRNA 水平显著升高。相应地，CCD 患者的 RANKL/OPG 和 RANKL/RANK mRNA 比值显著降低。
CCD 个体齿槽突中上述因子的表达和比值的改变表明，旁分泌信号对骨重塑的紊乱可能是这些患者牙齿萌出受损的原因。
