Wise Gary E, He Hongzhi, Gutierrez Dina L, Ring Sherry, Yao Shaomian
Department of Comparative Biomedical Sciences, School of Veterinary Medicine, Louisiana State University, Baton Rouge, USA.
Eur J Oral Sci. 2011 Oct;119(5):333-8. doi: 10.1111/j.1600-0722.2011.00854.x.
Tooth eruption is a localized event that requires a dental follicle (DF) to regulate the resorption of alveolar bone to form an eruption pathway. During the intra-osseous phase of eruption, the tooth moves through this pathway. The mechanism or motive force that propels the tooth through this pathway is controversial but many studies have shown that alveolar bone growth at the base of the crypt occurs during eruption. To determine if this bone growth (osteogenesis) was causal, experiments were designed in which the expression of an osteogenic gene in the DF, bone morphogenetic protein-6 (Bmp6), was inhibited by injection of the first mandibular molar of the rat with a small interfering RNA (siRNA) targeted against Bmp6. The injection was followed by electroporation to promote uptake of the siRNA. In 45 first molars injected, eruption was either delayed or completely inhibited (seven molars). In the impacted molars, an eruption pathway formed but bone growth at the base of the crypt was greatly reduced compared with the erupted first-molar controls. These studies show that alveolar bone growth at the base of the crypt is required for tooth eruption and that Bmp6 may be essential for promoting this growth.
牙齿萌出是一个局部性事件，需要牙囊（DF）调节牙槽骨的吸收以形成萌出通道。在萌出的骨内阶段，牙齿通过该通道移动。推动牙齿通过该通道的机制或动力存在争议，但许多研究表明，在萌出过程中，隐窝底部的牙槽骨会生长。为了确定这种骨生长（成骨作用）是否具有因果关系，设计了实验，通过向大鼠的第一下颌磨牙注射针对骨形态发生蛋白-6（Bmp6）的小干扰RNA（siRNA）来抑制DF中成骨基因的表达。注射后进行电穿孔以促进siRNA的摄取。在45颗注射的第一磨牙中，萌出要么延迟要么完全被抑制（7颗磨牙）。在阻生磨牙中，形成了萌出通道，但与已萌出的第一磨牙对照相比，隐窝底部的骨生长大大减少。这些研究表明，隐窝底部的牙槽骨生长是牙齿萌出所必需的，并且Bmp6可能对促进这种生长至关重要。
