Data from: Methodological validation and inter-site analysis in Late Bronze and Early Iron Age cremations using tooth cementum annulation

Most TCA studies have been conducted on contemporary materials from individuals of known calendar age and sex who underwent tooth extraction in dental clinics. Only a few studies have been undertaken on archaeological human skeletal remains and occasionally on cremated remains. 62 cremated tooth roots from 60 individuals from eight Lusatian Urnfield Culture cemeteries from SW Poland were studied. Based on analyses of 292 undecalcified slides with an average thickness of 36.1 µm embedded in methyl methacrylate resin, tests were carried out to estimate the age at death of individuals using the tooth cementum annulation (TCA) technique and, for slides with insufficient incremental lines of Salter counts (ILSc) identification, the incremental lines of Salter width (ILSw) parameter and the of acellular extrinsic fiber cementum thickness to line width (AEFCt/ILSw) ratio were introduced. The intra-observer error of repeatability of ILSc was 18.3%, while the inter-observer error was 29.6%. The expected statistically significant differences in AEFCt (P=0.0027) and an increase in ILSc (P=0.0068) with the ageing of individuals were shown. The TCA age corresponded with the individuals’ morphological age and with the age estimated based on AEFCt/ILSw ratio. The phenomenon of partial multiplication of the number of ILS was identified in two individuals. No differences in the ILSw were found within different parts of the dental root or between individuals of various ages and sexes. Differences in ILSw between individuals from different cemeteries proved to be statistically significant (P<0.001). Considering the absence of analogous studies, the explanation for this variation is multifaceted and may relate to genetic, ecological, nutritional and disease differences.绝大多数牙骨质环纹（tooth cementum annulation, TCA）相关研究均以牙科诊所中拔除的当代已知年龄与性别的人类牙齿为研究对象。仅有少量研究以考古出土的人类骨骼遗骸为对象，偶有针对火化遗骸开展的相关探索。本研究针对波兰西南部8座卢萨蒂亚瓮棺文化墓地出土的60名个体的62个经火化处理的牙根样本开展了分析。基于292张经甲基丙烯酸甲酯树脂包埋、平均厚度为36.1 μm的未脱钙切片，本研究采用牙骨质环纹法估算个体的死亡年龄；对于无法有效识别萨尔特增量线计数（incremental lines of Salter counts, ILSc）的切片，引入了萨尔特增量线宽度（incremental lines of Salter width, ILSw）参数以及无细胞外源性纤维牙骨质厚度与增量线宽度的比值（AEFCt/ILSw）作为辅助评估指标。ILSc的观察者内重复误差为18.3%，观察者间误差则为29.6%。研究证实，随着个体年龄增长，无细胞外源性纤维牙骨质厚度（acellular extrinsic fiber cementum thickness, AEFCt）存在统计学意义上的显著差异（P=0.0027），且ILSc呈上升趋势（P=0.0068）。TCA估算年龄与个体的形态学年龄以及基于AEFCt/ILSw比值得到的估算年龄具有一致性。本研究在2名个体中观察到了增量线数量部分倍增的现象。未发现牙根部不同区域的ILSw存在差异，亦未发现不同年龄、性别个体的ILSw存在显著区别。但不同墓地个体的ILSw差异具有统计学意义（P<0.001）。鉴于目前尚无同类研究，该差异的成因具有多面性，可能与遗传、生态环境、营养状况以及疾病差异相关。