Accuracy and reliability of cone beam computed tomography of the jaws for comparative forensic identification: a preliminary study

Conventional computed tomography is an emerging modality in forensic identification but is not sufficiently accurate for use in dental identification primarily because of problems with metallic dental restoration-induced streak artifact. In this study, the accuracy and reliability of recording forensic information from cone beam computed tomography (CBCT) scans of the jaws when compared to conventional panoramic radiographs has been analyzed under experimental conditions. Information could be recorded with near-perfect repeatability and reproducibility. Information could also be recorded accurately, the sensitivity being 96.6% (95% CI, 95.1-98.1) and specificity being 98.4% (95% CI, 96.2-100). The metal dental restoration-induced streak artifact was at a level that permitted, in most cases, accurate observations. This is considered an important step in validating CBCT as a tool in comparative dental identification of bodies. It may have a role in mass fatalities and in chemical, biological, radiological, and nuclear incidents, but further studies are required to assess the feasibility of this.     

中国汉族6～18周岁人群下颌恒牙钙化的性别差异研究

目的通过对中国汉族男女6～18周岁人群全口曲面断层影像上所显示的下颌左侧牙齿钙化程度进行比较研究,探究牙齿生长发育的性别差异,为建立用牙齿推断中国汉族儿童及青少年年龄的线性回归模型提供理论依据。方法通过对13491张(男6568张,女6923张)中国汉族6～18周岁儿童及青少年全口曲面断层影像的牙齿钙化规律进行研究,建立牙齿钙化的分级标准,并对下颌恒牙进行分级评分;数据用SPSS 13.0软件处理。结果非参数检验结果显示大部分年龄组下颌左侧8颗恒牙钙化分级值性别间的差异有统计学意义(P0.05);在8颗恒牙发育程度同等条件下,女性年龄比男性小0.303岁。结论中国汉族6～18周岁人群牙齿发育存在着性别差异;在利用牙齿钙化程度建立推断中国汉族儿童及青少年年龄的方程模型时,应分性别建模。     

Radiographic Recognition of Dental Implants as an Aid to Identifying the Deceased

Abstract:  This study was undertaken to determine if dental implants can be radiographically differentiated by company type to aid forensic identification of the deceased. Recognition of dental implants on intraoral radiographic images was assessed in a blind study using a radiographic examination guide to highlight differences between dental implants. Inter- and intra-examiner comparisons were conducted and a computer program (Implant Recognition System^®) was evaluated to see whether it improved the accuracy of implant recognition. The study found that dental implants could be radiographically differentiated by company type. The Implant Recognition System^® in its current form was of little benefit for radiographic assessment of dental implants for forensic odontologists. Prior knowledge of implant types, with a McNemar's statistical value of 92.9, proved to be most significant in identification.     

Study of Chilean Children’s Dental Maturation*

Abstract: In forensic science, determining a person’s chronological age has become a challenge for researchers. Determining age using dental calcification is becoming increasingly important. The objective of this study is to estimate the dental age of the children’s population in Region VIII, Chile. The sample was randomly taken from children under the care of the Faculty of Dentistry at the Universidad de Concepción in Chile. The study encompasses 159 children between 3 and 14 years of age. The dental age was determined following the Demirjian method. The Bland–Altman method was applied to establish the correlation. It was determined that the range between chronological and dental age is similar, and the degree of correlation between both ages is nearly perfect. In conclusion, the degree of correlation between the chronological and dental ages for each gender is also very good although it is slightly higher for females.     

关于增设消除犯罪记录型缓刑之立法建议的置疑

伴随着对前科消灭制度关注度的日益升高,在刑法领域内盲目套用前科消灭理论的不正确做法逐渐增多,关于增设＂消除犯罪记录型缓刑＂的观点就是表现之一。此种学说的关键理论依据在于：缓刑考验期满后,保留犯罪记录会对缓刑犯产生标签效应,不利于其社会复归。对于此种学说的规模化出现应当加以系统的反思和批判,清晰地区分国内外刑事立法体系的差异,确立正确的缓刑观,坚持用审慎的眼光去分析缓刑制度与前科消灭理论的相互界限和各自相互独立的立法初衷,防止类似不正确观点的进一步扩大化。     

A Comparison of US and Japanese Dental Restorative Care Present on Service Members Recovered from the WWII Era

The documentation of dental materials used in the USA during the WWII era is readily available, while references for the Japanese are minimal. It was therefore important to build a photographic database of Japanese restorative care which could be utilized as a comparison tool for the deployed odontologist. The dental restorative care of approximately 400 US and 100 Japanese sets of remains was evaluated. Both countries share many similar restorative techniques to include collared crowns, full‐coverage restorations, cantilever bridge/pontics to close spaces; restorative materials such as amalgam, gold, and zinc phosphate (temporary) restorations; and removable prostheses. The dental restorative materials most commonly used by US dentists include the amalgam and silicate cement, while the full‐coverage crown was the type of restoration most frequently seen on the Japanese remains. Silicates, porcelain and replaceable crowns, and partial‐coverage prepared crowns were not observed on the recovered Japanese remains.     

不同离体时间对非血管化游离骨移植同期种植血供建立的影响

目的:观察不同离体时间对非血管化游离骨块同期种植在体内血管形成的情况,了解非血管化游离骨块离体后时间的长短对其植入体内后成活的影响。方法:截除狗下颌骨的无牙颌骨段,取自体非血管化的髂骨块,在离体10、20和80分钟内植入纯钛金属种植体,修复下颌骨的节段性缺损处,恢复下颌骨的连续性,分别在术后1,2,4周处死动物取材前用墨汁灌注和八因子抗原染色进行血管标记。结果:在术后1、2、4周的时间点,可见非血管化的骨块内墨汁灌注的血管数逐渐增多,标志血管的内皮细胞由团块状,同心圆状,逐渐向中空的血管样演变,离体10分钟和20分钟组之间有所差别,但没有统计学的意义,P>0.05;80分种组墨汁灌注血管较少,八因子标记的血管出现较晚,计数较少,与离体10和20分钟组之间有着显著的差异,P<0.05。结论:非血管化游离骨块同期种植体修复颌骨节段性缺损时,游离骨块的离体时间是影响血管生成的因素之一,离体时间越短越有利于血管的生成和移植骨的成活。