Decayed, filled and missing teeth as a forensic-odontologic aid for determining the age above 18 years: A radiographic study of orthopantomograms from a group of teenagers and young adults

The human teeth are a valuable source of information concerning identification and age calculation in forensic sciences. Dental treatment often causes permanent alteration of the teeth, which is visible on radiographs. The correlation of decayed, missing or filled teeth and chronological age has not yet been used for determining the accomplished 18th year of life in teenagers and young adults, e. g. for legal and anthropological purposes. The aim of this study was to determine whether the evaluation of these findings on radiographs correlates with the chronological age in teenagers and young adults. MATERIAL AND METHODS: The dental X-rays (orthopantomograms, OPG) of 1053 outpatients (age: 14 to 24 years) were evaluated. The values "decayed", "missing", or "filled" were recorded for each tooth present. The data were then calculated using statistical tools. RESULTS: The correlation between the number of missing teeth and the chronological age is low. However, the positive predictive value of determining the age of 18 years for certain types of teeth proved to be very high, even up to 100 %. Further, high numbers of filled teeth gave reasonable positive predictive values for an age of 18 years. The number of decayed teeth did not correlate with age. DISCUSSION: This study provides for the first time predictive values for the estimation whether a person is 18 years of age, based on the evaluation of decayed, missing or filled teeth on OPGs only. Whereas the number of patients with such findings is generally low in this age group, some of the positive findings can be used for age estimation as an adjunct to other sources of age calculation. The sole application of these items is not recommended, as sanitary conditions of the teeth depend on both social and individual circumstances. Therefore, the calculated values also reflect the culture of the sample studied. Finally, they are time-dependent and have to be compared to data from other populations. These results have some bearing on the field of forensic odontology.     

Third molar root development in relation to chronological age: a large sample sized retrospective study

The aim of the present investigation, which is a continuation and extension of a previous published pilot study [Forensic Sci. Int. 129 (2002) 110], was to calculate the chronological age of an individual based on the dental developmental stages of third molars (so-called wisdom teeth). The evaluated material consisted of 2513 orthopantomograms (OPG's) of patients all of Belgian Caucasian origin between 15.7 and 23.3 years. The sample of OPG's was scored by two observers who were calibrated for intra- and interobserver reliability by means of kappa statistics. The kappa statistics revealed a strong agreement between the intra- and interobserver measurements. Further statistical analysis was performed in order to obtain multiple regression formulae for dental age calculation with the chronological age as the independent variable and the third molar developmental stages as dependent variables. Both for males and females a significant Pearson correlation coefficient was noticed for contralateral third molars, a smaller less significant one for the antimeres. For the application of the regression formulae one has to take into consideration the gender, the location and number of wisdom teeth. Probabilities for an individual to be older than 18 years were also calculated in case of fully developed wisdom teeth.     

Estimating Age of Majority on Third Molars Developmental Stages in Young Adults from Thailand Using a Modified Scoring Technique*

Abstract: The aim of this study was to achieve a referral database for dental age estimation of unaccompanied minors of Thai nationality. A total of 1199 orthopantomograms were collected from original Thai women and men equally divided in age categories between 15 and 24 years. On the radiographs, the developmental stage of the third molars was scored applying a modified scoring technique. Inter- and intra-observer reliabilities were tested using kappa statistics. Correlation between the scores of all four wisdom teeth and left–right symmetry were evaluated with Pearson’s correlation coefficient. Student’s t-test on asymmetry was performed and regression formulas were calculated. The present database was the first to assemble third molar developmental scores on radiographs of Thai individuals and provides more appropriate dental age estimation of unaccompanied Thai minors. Future research on similar databases of different nationalities worldwide may expose ethnical influences on dental development.     

Radiographic survey of third molar development in relation to chronological age among Japanese juveniles

The aim of the present study was to establish Japanese reference material on the third molar development of Japanese juveniles for forensic application. Observations were performed on the orthopantomograms of 1282 Japanese patients between the ages of 14.0 and 24.0 years. Demirjian formation stages of the maxillary and mandibular third molars were recorded for chronological evaluation of wisdom teeth and applied for further statistical analysis. Statistically significant differences were noted between the upper and lower jaws and genders. Accordingly, males achieved root developmental grades earlier than females. We assessed the mean ages for all formation grades and predicted the probability that a Japanese juvenile would be older than the relevant ages of 14, 16, and 20 as defined by Japanese Juvenile Law. We determined the likelihood that a Japanese youth is older than the relevant age of 18 as defined by legislation in the United States.     

Prosthetic restorations, dental root fillings and periodontal bone resorptions as a forensic-odontologic aid for determining the age above 18 years: A radiographic study of orthopantomograms from a group of teenagers and yount adults

The human teeth are a valuable source of information concerning identification and age calculation in forensic sciences. Dental treatment often causes permanent alteration of the teeth, which is visible on radiographs. The correlation of prosthetic restorations, root canal fillings and periodontal bone loss with chronological age has not yet been used for determining the completed 18th year of life in teenagers and young adults, e. g. for legal and anthropological purposes. The aim of this study was to determine whether the evaluation of such findings on radiographs correlates with the chronological age in teenagers and young adults. MATERIAL AND METHODS: The dental X-rays (orthopantomogram, OPG) of 1053 outpatients (age: 14 to 24 years) were avaluated. The values "prosthetically restored", "filled dental root", or "periodontal bone loss" were recorded for each tooth present. The data were then evaluated using statistical tools. RESULTS: The correlation between the number of prosthetically restored teeth and the chronological age is high. The positive predictive value of determining an age of at least 18 years proved to be very high. However, these findings are rarely present in this age group. The number of endodontically treated teeth correlated less exactly with age. On the other hand, the determination of periodontal bone loss gave reasonable positive predictive values for the threshold value "chronological age of 18 years or more". DISCUSSION: This study provides for the first time predictive values for the estimation whether a person is 18 years of age, based on the evaluation of teeth with prosthetic restorations, root canal fillings or periodontal bone loss on OPGs only. Whereas the number of patients with such findings is generally low in this age group, some of the positive findings can be used for age estimation as an adjunct to other sources of age calculation. The sole application of these criteria is not recommended, as sanitary conditions of the teeth depend on both social and individual circumstances. Therefore, the calculated values also reflect the culture of the sample studied. Finally, they are time-dependent and have to be compared to data from other populations. These results have some bearing on the field of forensic odontology.     

Studies of the chronological course of wisdom tooth eruption in a Black African population

The importance of forensic age estimation in living subjects has grown over the last few years. In dental age estimation, tooth eruption is a parameter of developmental morphology that can be analyzed by either clinical examination or by evaluation of dental X-rays. In the present study, we determined the stage of wisdom tooth eruption in 410 male and 106 female Black South African subjects of known age (12-26 years) based on radiological evidence from 516 conventional orthopantomograms. Four eruption stages were determined (no emergence, alveolar emergence, gingival emergence, complete emergence). Statistical scores were determined for the individual stages separately for both sexes. The data presented here can be utilized for forensic estimation of the minimum and most probable ages of investigated persons.     

Application of a modified stage classification in evaluating wisdom tooth eruption in a German population

The evaluation of the eruption status of the wisdom teeth constitutes a significant component of the spectrum of dental methods available for purposes of forensic age diagnostics. In the present study, the status of wisdom tooth eruption was identified in 606 conventionally created orthopantomograms of 515 female and 91 male Germans, divided by sex and tooth, using a modified classification comprising four stages. Instead of the original stage C (gingival eruption) which cannot always be reliably identified on X-ray images of suboptimal quality, stage C of the modified classification was considered reached when the erupting wisdom tooth had reached at least half the length of the crown of the adjacent second molar, without however having yet reached the occlusal plane. The new stage classification is especially recommended for age estimation based on X-ray images in which a conclusive delimitation of the gingiva is not possible.     

Measuring the distance of the wisdom teeth from the occlusal plane as forensic-odontological method for chronological age determination

As part of an epidemiological study on tooth eruption it was attempted to define easily accessible criteria for age estimation in living human beings based on the distance of the wisdom teeth from the occlusal plane. 253 cast models of 149 female and 104 male patients were used for evaluation. Due to the great variability observed in the eruption of the wisdom teeth, only a small fraction of the total number of 10,924 cast models was suitable for investigation. Only teeth with the axis being perpendicular to the plane of occlusion during eruption according to radiological and clinical findings were included. After defining these inclusion criteria, the distance of the wisdom teeth from the plane of occlusion was determined and correlated to the age of the subjects. The results confirmed the known large variability concerning wisdom tooth eruption and did not show any reliable relation between age and distance values. Nevertheless, a remarkable finding that may be relevant for forensic odontostomatology was seen in one case where the lower wisdom teeth were taller than the occlusal plane, although the female patient was younger than 14 years. The upper molars were retained and root development was incomplete.     

Radiologically determined DMF index variations for forensic age estimation of young adults

The eruption and mineralization of third molars are the main criteria for dental age estimation of living people involved in criminal proceedings. Since the development of third molars is usually completed by the age of 19 or 20 years, this feature cannot be used to ascertain whether a person has attained the forensically relevant age of 21 years. This study examined whether the DMFT index or the third molar DFT index could supply reliable information enabling conclusions to be drawn about whether a person has reached the age of 21. To this end, 650 conventional orthopantomograms of German subjects aged 18 to 30 years were evaluated. The DMF index variations considered were found to be unsuitable for determining whether a person is over 21 because they displayed a weak correlation with age and considerable individual scatter. A high indicative value can only be attributed to a third molar DFT index of 4, although this is rarely observed in the relevant age group. An X-ray examination of the medial clavicular epiphyseal cartilage is, therefore, strongly recommended when assessing whether a person has attained 21 years of age.     

Studies of the chronological course of wisdom tooth eruption in a Japanese population

The importance of forensic age estimation in living subjects has grown over the last few years. In dental age estimation, tooth eruption is a parameter of developmental morphology that can be analyzed by either clinical examination or by evaluation of dental X-rays. In the present study, we determined the stage of wisdom tooth eruption in 549 male and 751 female Japanese subjects aged 14-26 years based on radiological evidence from 1300 conventional orthopantomograms. The results presented here provide useful data on the age of alveolar, gingival, and complete emergence of the third molars in the occlusal plane that can be utilized for forensic estimation of the minimum and most probable ages of investigated persons.     

陕西省6～15岁汉族未成年人牙龄的研究

目的运用全口曲面断层影像技术,研究陕西省6-15岁汉族未成年人牙齿钙化规律,建立利用牙齿钙化程度推断陕西汉族6-15岁未成年人年龄的方法。方法按照中国汉族儿童及青少年牙齿钙化分级标准,对1997名（男934名,女1063名）陕西省6-15岁汉族未成年人的全口曲面断层影像中下颌恒牙钙化程度进行分级评分;将所得评分值及对应的年龄输入SPSS软件并进行统计分析,最终建立年龄推断的方程。结果下颌同名牙钙化评分值侧别间非参数检验结果 P〉0.05,而性别间非参数独立样本检验结果 P〈0.05;下颌左侧各颗恒牙钙化程度与年龄相关分析结果 r〉0.59;方程拟合优度检验所得校正决定系数均大于0.76,估计值标准误男性在0.85-1.05岁之间、女性在0.83-0.97岁之间。结论本研究建立的方法合理可靠,可用于陕西省汉族6-15岁未成年人年龄的推断。     

重庆地区汉族未成年人牙龄推断的研究

目的运用牙齿曲面断层影像技术,研究6周岁～15周岁重庆市未成年人牙齿钙化的规律,从而建立根据牙齿钙化程度推断年龄的方法。方法依据牙齿钙化分级标准对1321名（男性577名,女性744名）重庆市6周岁～15周岁未成年人牙齿曲面断层片上的牙齿钙化程度进行分级评分;将评分值与对应的性别和年龄分别输入SPSS13.0软件进行统计分析,最终建立推断年龄的方程。结果左右侧同名牙齿钙化程度无统计学差异（P〉0.05）,但性别间有统计学差异（P〈0.05）;下颌左右侧8颗牙齿的钙化程度与年龄相关系数均大于0.58;所建利用不同牙齿组合推断年龄的线性回归模型调整拟合优度均大于0.67,估计值标准误男性为0.95周岁～1.11周岁、女性为1.02周岁～1.12周岁。结论该方法可用于法庭科学领域中推断重庆市6周岁～15周岁未成年人活体以及尸体的年龄。     

Dental age estimation and third molars: a preliminary study

The aim of the present investigation was to reconstruct the chronological age based on the dental developmental stages of third molars evaluated on orthopantomograms. A total of 1175 orthopantomograms were assembled from patients of Caucasian origin between 16 and 22 years of age. Each third molar present was scored by two observers according to a 10-stage developmental scale. The kappa statistics measured the intra- and inter-observer reliability. The general statistical analysis was based on multiple regression analysis in order to obtain multiple regression formulas for dental age estimation based on the number of third molars present on the evaluated orthopantomogram. No regression models were statistically significant when there was only one-third molar present because of the relatively small number of orthopantomograms that fitted this criterion. A strong agreement was found between the intra- and inter-observer measurements. The statistical analysis revealed both for males and females high Pearson correlation coefficients between contralateral third molars and smaller coefficients between antimeres. The obtained multiple regression formulas are only applicable in certain specified conditions, for instance when four third molars are present the following formulas should be used in a Caucasian male "age=10.2000+0.5122UL+0.5273LL" (developmental stage of upper and lower left third molars) or in case of a female "age=13.6206+0.1933UR+0.5080LR" (developmental stage of upper and lower right third molars). This investigation revealed that the chronological age of a Caucasian individual may be estimated based on regression formulas with a S.D. of 1.52 or 1.56 years for males and females, respectively, when all four third molars are present.     

Age estimation from root development of mandibular third molars in comparison with skeletal age of wrist joint

Identification of the living person and the dead is of paramount importance for variety of reasons in forensic practice routinely. Age estimation is one of the prime factors employed to establish identity. Estimating age from teeth is generally reliable as they are naturally preserved long after all the tissues and even bones have disintegrated. A study was done to determine the age by root developmental changes, using the intraoral periapical radiographs of the mandibular third molars, adopting the Leif Kullman et al method. Three hundred forty-six girls and 389 boys of the age range 15-25 years, among the South Indian population of young adults from various schools and colleges in the vicinity of Dakshina Kannada and Udupi Districts and also among the patients visiting the outpatient department of Oral Medicine and Radiology, College of Dental Surgery, Manipal, were considered for this study. The subjects were roentgenographically examined to determine the age from the 7 stages of root development of the left mandibular third molar. Depending on the exact stage of root development as seen in the radiograph, the chronologic age was determined. This method sheds a new light on determining the ages of 15, 16, and 18 years, which has an immense medicolegal bearing.     

Age estimation of Korean children based on dental maturity

The aim of this study was to evaluate the relationship between age and dental maturity and to establish the standard database of dental maturity based on the Demirjian's stages, which can be used for the age estimation of Korean children. For this purpose, dental maturity was measured by the Demirjian's stages on a randomly selected sample of panoramic radiographs taken from 2706 patients between 1 and 20 years of age and analyzed by multiple linear regression analysis based on the method of least squares. The results showed that, except for the third molars, the development of permanent teeth in Korean children was more advanced in females. The Demirjian's stage G of the second molar appeared last in both male and female subjects by age 18, showing 95th percentile at age in the male and female subjects between 16.7-17.4 years and 17.1-17.3 years, respectively. Coefficients of determination (r(2)) of the Demirjian's stages relative to age in regression analysis were 0.9721 in male and 0.9740 in female subjects. The standard error was 0.63 years in male and 0.62 years in female subjects. The estimated age according to regression analysis was within +/-1.0 year of the actual age in 92.0% of male and 92.5% of female subjects. Collectively, the data of the present study can be used as a reference for dental maturity and a standard for age estimation of Korean children.     

Age estimation by pulp/tooth ratio in lower premolars by orthopantomography

Accurate age estimation has always been a problem for forensic scientists, and apposition of secondary dentine is often used as an indicator of age. Since 2004, in order to examine patterns of secondary dentine apposition, Cameriere et al. have been extensively studying the pulp/tooth area ratio of the canines by panoramic and peri-apical X-ray images. The main aim of this paper is to examine the relationship between age and age-related changes in the pulp/tooth area ratio in monoradicular teeth, with the exception of canines, by orthopantomography. A total of 606 orthopantomograms of Spanish white Caucasian patients (289 women and 317 men), aged between 18 and 75 years and coming from Bilbao and Granada (Spain), was analysed. Regression analysis of age of monoradicular teeth indicated that the lower premolars were the most closely correlated with age. An ANCOVA did not show significant differences between men and women. Multiple regression analysis, with age as dependent variable and pulp/tooth area ratio as predictor, yielded several formulae. R(2) ranged from 0.69 to 0.75 for a single lower premolar tooth and from 0.79 to 0.86 for multiple lower premolar teeth. Depending on the available number of premolar teeth, the mean of the absolute values of residual standard error, at 95% confidence interval, ranged between 4.34 and 6.02 years, showing that the pulp/tooth area ratio is a useful variable for assessing age with reasonable accuracy.     

Morphologic analysis of third-molar mineralization for eastern Turkish children and youth

To date, there has been no chronological age estimation according to third-molar mineralization in eastern Turkish children and adolescents. The aim of this study was to analyze the development of the mandibular third molar and its relationship to chronological age in subjects aged 7-22 years according to Demirjian's stages. The final sample consisted of 1348 [622 males (mean age, 12.72 ± 3.14) and 726 females (mean age, 12.92 ± 2.89)] conventional orthopantomograms from eastern Turkish youths. An independent t-test was performed to evaluate the difference between sexes. Regression analysis was performed to obtain regression formulae for dental age calculation with chronological age. In males, there was a difference between males and females only at stage C (p = 0.03); females were advanced 0.37 years compared with males at the stage C. Third-molar development among eastern Turkish children and youths occurs at a more advanced age than other populations for almost all stages.