Ranly D M, Thomas H F, Chen J, MacDougall M
Department of Pediatric Dentistry, University of Texas Health Science Center at San Antonio 78284, USA.
J Endod. 1997 Jun;23(6):374-7. doi: 10.1016/S0099-2399(97)80186-0.
Dental pulps were obtained from third molars of young adults (17-25 yr) or from molar teeth of individuals > 50 yr of age and examined for the expression of osteocalcin (OC) mRNA by RT-PCR. OC was selected as a determinant of pulp vitality, because it has long been associated with the production of hard tissue matrix in teeth and bone. For comparative purposes, the expression of OC in each pulp was normalized relative to its housekeeping gene-product GAPDH by the establishment of a OC/GAPDH ratio. This study demonstrated that OC expression, presumably by cells of odontoblast lineage, does not diminish relative to the extant cell population. Our findings suggest, despite a reduction in volume and cell numbers, that the pulps of aging teeth retain a capacity for dentin deposition and a potential for caries and trauma resistance.
从年轻成年人（17 - 25岁）的第三磨牙或50岁以上个体的磨牙获取牙髓，并通过逆转录聚合酶链反应（RT-PCR）检测骨钙素（OC）mRNA的表达。选择OC作为牙髓活力的一个决定因素，因为长期以来它一直与牙齿和骨骼中硬组织基质的产生有关。为了进行比较，通过建立OC/GAPDH比值，将每个牙髓中OC的表达相对于其管家基因产物甘油醛-3-磷酸脱氢酶（GAPDH）进行标准化。这项研究表明，推测由成牙本质细胞谱系的细胞表达的OC，相对于现存细胞群体而言并未减少。我们的研究结果表明，尽管牙髓体积和细胞数量减少，但老龄牙齿的牙髓仍保留牙本质沉积能力以及抗龋和抗创伤的潜力。
