应用数字图像识别系统研究正畸治疗前后腭皱形态变化

目的利用腭皱数字图像识别系统对正畸治疗前后腭皱形态匹配正确率的分析研究,为法医学中同一认定提供理论依据。方法利用正畸患者治疗前后腭皱形态数字图像,通过腭皱数字图像识别系统对图像的特征进行提取并收录到腭皱数字库,运用Matlab软件完成对腭皱形态数字图像的信息匹配处理。结果正畸治疗前后,个体性检测匹配正确率各自都达到100%。正畸治疗前后腭皱形态匹配正确率为95.67%,配对检验结果 P0.05,具有统计学意义。结论腭皱形态具有高度的个体特异性,正畸治疗后腭皱形态会发生多种变化,但对同一认定的影响不大。腭皱形态识别为法医学同一认定提供一种新的方法和途径。     

利用腭皱特征进行同一认定的指标体系构建

目的根据腭皱的形态图特征,进行口腔腭皱在法医学同一认定的指标体系构建。方法收集100例成年人腭皱模型,依据腭皱的形状、数量、位置分布等特征对腭皱形态图进行全面系统的编码。编码顺序采用英文字母按照先右侧再左侧,先前部再后部的顺序编码,并且右、左侧编码以破折号连接。最后依据编码,统计分析腭皱形态分布特征。结果 100例腭皱形态图中,个体间未见完全一致者,每个个体不论男性与女性均表现有独特的腭皱形态图;且同一个体左右侧单条腭皱的形态及分布亦不同。波浪形腭皱所占比例最大（23.03%）,三分叉形出现比例最小（0.74%）,不同性别的波浪形及曲线形腭皱所占比例均较大,女性波浪形（22.7%）及曲线形（18.28%）;男性波浪形（24.11%）及曲线形（21.43%）。结论口腔腭皱法医学同一认定的指标体系构建,将为法医学的同一认定提供一种新的方法。     

人牙咬痕同一认定数字化分析的盲法评定

目的评定人牙咬痕同一认定数字化分析方法的精确性。方法 采用数字化分析法对人牙咬痕及8名“疑犯”牙列模型进行双盲法分析实验,用Photoshop 5.5将获得的咬痕扫描图像生成overlay,用AutoCAD Rl4工程测量软件分析各项参数,比较人牙咬痕和“疑犯”牙列参数的匹配性。结果人牙咬痕及“疑犯”牙列模型数据化分析的各项参数分析结果一致。结论对于试验性咬痕,数字化分析是一种可行的认定方法,对法医学实践具有可行性及良好的应用前景。     

正畸治疗前后腭皱的法医同一认定研究

目的利用腭皱模型分析法评价腭皱形态的个体独特性及正畸治疗前后腭皱形态的稳定性,探索腭皱形态在法医齿科学个体识别应用中的可靠性。方法分别收集70例正畸治疗前、后的上颌模型。通过模型测量分析对腭皱形态及个体识别进行检测,包括数量、方向、形状及长度的变化和近、远中侧端点分别在近远中向及前后方向上的位移。同时对正畸治疗前、后及正畸治疗后与其复制后腭皱模型进行配对检测,计算其平均正确配对率(%)。结果 (1)正畸治疗后腭皱数量、方向、形状及长度均有变化,表现为长度变化(28.6%);分裂(4.3%);联合(2.9%);方向变化(1.4%);形状变化(1.4%)。并且治疗后腭皱远中端点的前后向位移变化占45.7%,近远中向位移占40%;而腭皱近中端在在前后向和在近远中向上位移变化分别为32.9%和17.1%。(2)正畸治疗前组及正畸治疗后组不同个体均未发现相同的腭皱模式。(3)正畸治疗前、后模型的腭皱平均正确配对率为92.19%。而治疗后模型与复制后模型的腭皱平均正确配对率是99.05%。结论腭皱形态具有高度的个体特异性,尽管正畸治疗后腭皱的形态有一定变化,但仍可作为一种新的方法应用于法医齿科的同一认定。     

成人腭皱三维数字模型特征与性别相关性研究

目的 建立成人腭皱三维数字模型并研究其特征与性别的相关性.方法 本研究收集102名成人的上颌三维数字模型,男女各51名;记录腭皱型及两侧第一条腭皱的位置,并对其进行统计分析,以评价腭皱特征与性别的关系.结果 在不同性别人群中共观察到共850条腭皱,其中男性420条(49.41％),女性430条(50.59％).直线形腭...     

放射影像学在法医学同一认定中的应用

应用放射影像学进行同一认定是法医放射学重要的研究方向之一。本文通过阐述放射影像学在法医学同一认定中的应用范围、历史性回顾、可用于同一认定标志的类型、注意事项和今后发展方向，为进一步完善放射影像学在法医学同一认定中的应用提供参考。     

数字全口牙位曲面体层片的法医学同一认定指标

目的采用颌面全口牙位曲面体层片,针对牙齿无病变者筛选简洁实用的法医学同一认定识别指标并进行编码、统计分析及评估。方法随机选取170例牙齿无病变者的颌面数字全口牙位曲面体层片进行观测．根据牙齿的生理变异特征和牙齿的排列特征分别筛选全口牙型和牙列型识别指标。按设计的编码标准对全口牙型、牙列型逐一编码,统计分析编码的多样性,以评估两类识别指标的应用价值。结果170例中共有74种全口牙型编码,多样性为43．53％：170例中共有129种牙列型编码,多样性为75．88％;170例同时进行全口牙型和牙列型编码．则共有150种全口牙型／牙列型编码,多样性为88．24％。结论全口牙型编码多样性较低,单独使用尚不能满足法医学同一认定的要求。牙列型编码的多样性比较高,具有一定的法医学同一认定价值。如果同时进行全口牙型和牙列型编码,多样性明显提高,有较高的法医学同一认定价值。     

北京汉族群体9个STR位点的频率分布及法医学应用

提供北京汉族群体9个STR基因座的频率分布资料，了解其在法医学中的应用价值。应用PCR技术对9个STR基因座分3组进行复合扩增，经PAG电泳分离、银染，扫描仪扫描，计算机判读并保存结果，对北京地区汉族无关个体9个基因座的基因频率分布进行调查。结果显示，上述9个基因座的杂合度为0．6419～0．8092，多态性信息总量为0．9999，鉴别机率为0．9999，匹配机率为2．0×10-9和非父排除率为0．9985。STR3组9个基因座的综合检验可应用于法医学个体识别和亲子鉴定，并达到同一认定的标准。     

医疗纠纷法医学鉴定质量评价模型的建立

目的建立医疗纠纷法医学鉴定质量评价模型。方法收集同济医学院法医学系近10年410例涉及医疗纠纷的法医学鉴定的案例,对影响医疗纠纷法医学鉴定质量的10个关键指标,运用SAS软件进行了主成分分析。结果通过统计学分析,筛选出6个能反映所有原指标变量主要信息的主成分,并依此结果推算出评价法医学系医疗纠纷的鉴定质量评价模型。结论在建立“医疗纠纷鉴定质量管理体系”时,应按影响鉴定质量的主成分设计相应的对策。     

放射影像资料的法医临床学同一认定14例分析

放射影像学在法医学中主要是应用X线、CT和MRI等技术方法,识别身体异物、判断有无损伤、推断损伤时间及损伤机制,同时还可以用于同一认定,特别是对于重大灾祸如空难、海难及刑事案件中肢解、碎尸、白骨化、高度腐败等无法辨认的尸体的认定。法医临床学鉴定实践中则会遇到需要对不同时期的放射影像资料进行同一认定的案例。本文就法医临床学鉴定实践中对放射影像学资料进行同一认定的报告,结合有关文献,探讨法医临床学中对放射影像学资料进行同一性鉴定的原则及注意事项。1材料和方法从1995年至2004年10年间四川华西法医学鉴定中心法医临…     

Stability of Palatal Rugae as a Forensic Marker in Orthodontically Treated Cases

The palatal rugae have been used as a reference landmark and identification marker by orthodontists and forensic analysts. However, the reliability of palatal rugae as a forensic marker remains questionable once an individual is subjected to orthodontic treatment. This study aimed at evaluating the changes in the rugae pattern after nonextraction, extraction, and maxillary expansion orthodontic treatment. The lengths and shapes of palatal rugae were evaluated on the pretreatment and post‐treatment dental casts of 168 subjects using the Thomas and Kotze classification. Extraction treatment significantly reduced the second and third rugae lengths (p < 0.05), whereas the third rugae length was significantly increased after palatal expansion (p < 0.05). The shape of rugae remained consistent in all the study groups which may be used as a reliable forensic marker in subjects undergoing orthodontic treatment. However, the use of the lengths of palatal rugae in forensic odontology must be made with caution.     

The Heritability of Palatal Rugae Morphology Among Siblings*†

Although there is clinical applicability of the palatal rugae as an identification tool in forensic odontology, controversy exists whether the palatal rugae patterns are stable or variable. The greater the genetic component, the higher the probability that palatal rugae patterns are stable. The aim of this study was to compare the palatal rugae morphology between full siblings and the proportion of variability due to genetic component. This cross-sectional study was conducted on digital models of 162 siblings aged 15–30 years old. The palatal rugae patterns were assessed with Thomas and Kotze (1983) classification using Geomagic Studio software (3D Systems, Rock Hill, SC). The palatal rugae morphology between siblings showed significantly similar characteristics for total number of left rugae (p = 0.001), left primary rugae (p = 0.017), secondary rugae for right (p = 0.024) and left sides (p = 0.001), right straight rugae (p = 0.010), and right convergent rugae (p = 0.005) accounting for at least 6.25%-12.8% of the variability due to heredity. Despite the similarities found, the palatal rugae patterns showed significant differences between siblings of at least 46.9% (p = 0.001). Zero heritability was found in 9 of the 14 rugae patterns. Meanwhile, total number of rugae, primary, backward, and convergent rugae showed moderate heritability (h² > 0.3) and total number of secondary rugae showed high heritability (h² > 0.6). In conclusion, despite the individuality characteristics, an appreciable hereditary component is observed with significant similarities found between sibling pairs and the palatal rugae patterns were both environmentally and genetically influenced.     

Rugoscopy: Predominant Pattern,Uniqueness, and Stability Assessment in the Indian Goan Population

The palatine rugae possess unique characteristics that could be used when it is difficult to identify a dead person according to fingerprints or dental records. They are permanent and unique to each person. The rugae are surrounded by cheeks, lips, tongue, and buccal pad of fat; hence, they remain protected in trauma, incineration, or mass disasters. Their pattern of orientation is formed by the 12th to 14th week of gestation and remains stable throughout life. In this study, dental casts of 120 patients were analyzed for individual rugae characteristics and strength and subsequent individual codes were given. No two individuals were having exactly matching rugae codes. Dimensions of rugae pattern, incisive papilla, and midpalatal raphe were also noted. Rugae were reevaluated after one year to check its stability, which showed no significant difference. The coding system followed can be adopted as a good and simple technique to achieve electronic transfer of the records of the palatal rugae.     

法医学鉴定标准的现状与问题

司法鉴定标准化是一个世界性的司法话题,伴随我国司法改革的实施和政府对标准化工作的重视,我国将迎来建立法医学鉴定标准体系的黄金时代。然而当前我国法医学鉴定标准却存在标准少、质量参差不齐、更新缓慢、标准制定的科学性不足等问题,导致司法鉴定工作与实践脱轨,很多鉴定项目缺乏鉴定标准。为此,作者建议,正确认识法医学鉴定标准的法律地位和存在的错误,致力于法医学鉴定标准化。     

Palatal rugae pattern in a Portuguese population: a preliminary analysis

Palatal rugae have been related with specific racial groups and are said to be useful in sex discrimination. This work aimed to characterize the palatal rugae patterns in a Portuguese population. Fifty plaster casts were examined for first and third rugae shape evaluation; shape, frequency, and association with sex were studied. In females, the most prevalent first rugae were the straight type on the right and the curve type on the left; in males, the straight type was the most prevalent on both sides. The most frequent third rugae type was sinuous on both sides, in both sexes. No significant sexual dimorphism in rugae shape was found (p > 0.05). When comparing these results with those from other investigations, it was clear that a particular rugae pattern could be established for different ethnic groups. However, the small sample size justifies further work in larger samples to validate these findings.     

Morphological pattern of palatal rugae in children of Davangere

The aim of this study was to identify and compare the rugae pattern between males and females of two different communities in the city of Davangere, Karnataka, India, which may be an additional method of identification in cases of crimes or communal riots. Elastomeric impressions of the maxillary arch of 100 selected children were made; casts were poured in Type IV stone. The method of identification of rugae pattern followed was that of Lysell and Thomas and Kotze, which includes the number, shape, direction, and unification of rugae. The study revealed no significant difference in the total number or length of rugae between the two communities and sexes. However, with regard to shape and unification, females showed a significantly higher diverging rugae type while males had a significant number of circular and converging type of rugae. Also, discrimination function analysis allowed a moderate differentiation of the population. Hence, the rugae pattern can be an additional method of differentiation in conjunction with the other methods such as visual, fingerprints, and dental characteristics in forensic sciences.     

Indication and limitations of using palatal rugae for personal identification in edentulous cases

To explore the availability and the limitations of using the palatal rugae pattern in forensic practice for personal identification in edentulous cases, we set up an experiment, which involved 48 patients who had both old and new complete dentures and we observed their rugae. First, we made 48 pairs of maxillary casts from their old and new dentures and a further 50 maxillary casts from complete dentures at random, to use as variables. All the initial impressions taken from the mucosal surfaces of complete dentures were made from alginate impression materials, and the maxillary casts were made from hard dental plaster. Secondly, all 146 casts were trimmed so that all the areas except for the rugae area were removed. Subsequently, 50 examiners were given the 48 casts from the old dentures and were then asked to compare them with the other 98 casts for possible matches. The case numbers, which matched correctly, were recorded. The median percentage of correct matches among the 50 examiners was 94%, despite variations in their experience with forensic identification, and this accuracy does not differ significantly from that in dentate cases, as described in previous publications. The median percentage of correct matches among the 48 cases was 90%. Analyzing the incidence of obtaining a correct match in each case revealed that there were three major misleading shapes that could give rise to a low rate of correct matches; (1) severely low and poorly demarcated eminences of rugae, (2) change of palatal height, and (3) non-complex rugae pattern. These features are mainly due to the shape of the edentulous palate itself and rarely due to the dentures, and could lead to difficulties in finding unique points for use in matching rugae patterns. The results suggest that an appropriate selection of cases, taking into consideration the above misleading shapes, may establish an increased rate of accuracy for identification with this method, thereby bringing the percentage of correct matches closer to 100% in edentulous cases, which is also the percentage of correct matches previously reported in dentate cases.