Merzel José, Salmon Cristiane R
Department of Morphology, Faculdade de Odontologia de Piracicaba, State University of Campinas -UNICAMP, SP, Brazil.
Anat Rec (Hoboken). 2008 Jul;291(7):827-34. doi: 10.1002/ar.20703.
The modeling and remodeling of the rat incisor alveolar bone was followed as the animals grew. The weight of the hemimandible, the length of the socket, and the width of the lower incisor were measured. Osteoclasts and resorption areas were identified by tartrate-resistant acid phosphatase staining. Fluorochrome markers were used to detect and measure osteogenic activities. In the socket related to the periodontal ligament, osteoclasts appeared in scattered sites as well as isolated sites of osteogenic activity, apparently without any variation related to the age of the animals. At the socket facing the dental follicle of young rats, the inner surface was lined with osteoclasts. The number of osteoclasts decreased steadily as the rats grew. In 1-year-old rats, in addition to a few scattered osteoclasts, the internal aspect of the labial wall showed some sites lined with osteoblasts and cement lines indicative of prior bone formation. In young rats, there was a continuous osteogenic activity at the external surface of this wall. The thickness of the labial wall of the socket remained apparently constant; therefore, bone resorption must have occurred at the internal side of the wall. Such osteogenic activity was not observed in old rats. The main forces acting on rat incisors, biting and eruption, are continuous through the life of the animals. Thus, these results indicate that the modeling of the alveolar bone related to the dental follicle, in young rats, can only be associated with another force, specifically, the growth of the incisor.
随着动物生长，对大鼠切牙牙槽骨的建模和重塑过程进行了跟踪。测量了半侧下颌骨的重量、牙槽窝的长度以及下切牙的宽度。通过抗酒石酸酸性磷酸酶染色鉴定破骨细胞和吸收区域。使用荧光染料标记物来检测和测量成骨活性。在与牙周韧带相关的牙槽窝中，破骨细胞出现在散在部位以及孤立的成骨活性部位，显然与动物年龄无关。在幼鼠面向牙囊的牙槽窝处，内表面衬有破骨细胞。随着大鼠生长，破骨细胞数量稳步减少。在1岁大鼠中，除了一些散在的破骨细胞外，唇侧骨壁内侧显示出一些衬有成骨细胞的部位以及表明先前有骨形成的黏合线。在幼鼠中，该骨壁外表面存在持续的成骨活性。牙槽窝唇侧骨壁的厚度显然保持恒定；因此，骨吸收一定发生在骨壁内侧。在老年大鼠中未观察到这种成骨活性。作用于大鼠切牙的主要力量，即咬合力和萌出力，在动物的一生中持续存在。因此，这些结果表明，幼鼠中与牙囊相关的牙槽骨建模只能与另一种力量相关，具体而言，是切牙的生长。
