On the increasing fragility of human teeth with age: A deep-UV resonance Raman study
On the increasing fragility of human teeth with age: A deep-UV resonance Raman study
复制标题
DOI：
10.1359/jbmr.060816
复制
发表时间：
2006-12-01
影响因子：
6.2
通讯作者：
Ritchie, Robert O.
中科院分区：
文献类型：
--
作者：
Ager, Joel W., III;Nalla, Ravi K.;Ritchie, Robert O.
使用244 nm激发的紫外共振拉曼光谱（UVRRS）来研究老化对人类牙本质的影响。胶原蛋白中的肽键的光谱特征的强度随着组织年龄的增加而增加，类似于以前报道的人皮质bone.Introduction：结构的变化，导致损害的机械性能与年龄的牙本质和骨正在紧张的研究。材料与方法：35颗磨牙分为3组：年轻组和正常组，年轻组和正常组，年轻组和正常组的牙体牙髓组织中的无机相含量和分布均高于正常组（23.3 +/- 3.8岁）;老化/透明（74.3 +/- 6.0岁），由于矿物质沉积物填充小管腔而变得透明;和老年/非转臂（73.3 +/- 5.7岁）。结果：观察到酰胺主链和共振增强侧链振动引起的光谱特征。这一发现与报告的拉曼光谱的蛋白质在溶液中激发类似的紫外波长，侧链振动，但没有强酰胺功能，观察。从牙本质观察到的酰胺特征的强强度归因于牙本质中胶原分子的环境引起的酰胺pi -> pi* 跃迁的共振分布的加宽。随着年龄的增长，一个特定的酰胺振动（酰胺1）的高度变得显着更高时，比较牙齿的平均年龄为23岁，73岁（p < 0.001）。酰胺I峰高随年龄增加的趋势与先前报告的人皮质骨相似。酰胺我的功能也增加了牙本质，已脱矿和dehydrant.Conclusions：随着年龄的增长，在UVRR光谱的牙齿和骨骼的酰胺我的峰高增加的类似趋势是令人惊讶的，因为只有骨进行重塑。然而，通过将这些观察结果与脱矿/脱水牙本质的本研究以及我们先前对用极性溶剂脱水的牙本质的研究一起考虑，可以开发UVRR光谱变化与组织中胶原蛋白环境之间的一致关系。
UV resonance Raman spectroscopy (UVRRS) using 244-nm excitation was used to study the impact of aging on human dentin. The intensity of a spectroscopic feature from the peptide bonds in the collagen increases with tissue age, similar to a finding reported previously for human cortical bone.Introduction: The structural changes that lead to compromised mechanical properties with age in dentin and bone are under intense study. However, in situ analyses of the content and distribution of the mineral phase are more highly developed at present than equivalent probes of the organic phase.Materials and Methods: Thirty-five human molars were divided into three groups: young/normal (23.3 +/- 3.8 years); aged/transparent (74.3 +/- 6.0 years), which had become transparent because of filling of the tubule lumens with mineral deposits; and aged/nontransparem (73.3 +/- 5.7 years). Control experiments were performed by demineralizing normal dentin.Results: Spectral features caused by both the amide backbone and resonance-enhanced side-chain vibrations were observed. This finding contrasts with reported Raman spectra of proteins in solution excited with similar UV wavelengths, where side chain vibrations, but not strong amide features, are observed. The strong intensity of the amide features observed from dentin is attributed to broadening of the resonance profile for the amide pi -> pi* transition caused by the environment of the collagen molecules in dentin. With increasing age, the height of one specific amide vibration (amide 1) becomes significantly higher when comparing teeth from donors with an average age of 23 years to those of 73 years (p < 0.001). This trend of increasing amide I peak height with age is similar to that previously reported for human cortical bone. The amide I feature also increased in dentin that had been demineralized and dehydrated.Conclusions: The similar trend of increasing amide I peak height with age in the UVRR spectra of both teeth and bone is surprising, given that only bone undergoes remodeling. However, by considering those observations together with this study of demineralized/dehydrated dentin and our prior work on dentin dehydrated with polar solvents, a consistent relationship between changes in the UVRR spectra and the collagen environment in the tissue can be developed.