The accuracy of three methods of age estimation using radiographic measurements of developing teeth

Third Molar Eruption in Dental Panoramic Radiographs as a Feature for Forensic Age Assessment-Presentation of a New Non-Staging Method Based on Measurements

The evaluation of third molar eruption in dental panoramic radiographs (DPRs) constitutes an evidence-based approach for forensic age assessment in living individuals. Existing methodologies involve staging morphological radiographic findings and comparing them to reference populations. Conversely, the existing literature presents an alternative method where the distance between third molars and the occlusal plane is measured on dental plaster models. The aim of this study was to adapt this measurement principle for DPRs and to determine correlation between eruption and chronological age. A total of 423 DPRs, encompassing 220 females and 203 males aged 15 to 25 years, were examined, including teeth 38 [FDI] and 48. Two independent examiners conducted the measurements, with one examiner providing dual assessments. Ultimately, a quotient was derived by comparing orthogonal distances from the mesial cementoenamel junctions of the second and third molars to a simplified radiological occlusal plane. This quotient was subsequently correlated with the individual's age. We estimated correlations between age and quotients, as well as inter- and intra-rater reliability. Correlation coefficients (Spearman's rho) between measurements and individuals' ages ranged from 0.555 to 0.597, conditional on sex and tooth. Intra-rater agreement (Krippendorf's alpha) ranged from 0.932 to 0.991, varying according to the tooth and sex. Inter-rater agreement ranged from 0.984 to 0.992, with distinctions drawn for different teeth and sex. Notably, all observer agreement values fell within the "very good" range. In summary, assessing the distance of third molars from a simplified occlusal plane in DPRs emerges as a new and promising method for evaluating eruption status in forensic age assessment. Subsequent reference studies should validate these findings.

Age estimation of children based on open apex measurement in the developing permanent dentition: an Egyptian formula

Background

Cameriere’s original formula based on open apex measurements is a reliable, clinically applicable method for dental age estimation in different populations children. Dental development may differ between Egyptian children and other ethnic populations which may affect dental age accuracy using Cameriere’s formula.

Aim

Firstly, to verify Cameriere’s original formula on large Egyptian children sample, secondly, to develop an Egyptian-specific formula based on Cameriere’s method.

Material and methods

A prospective cross-sectional study of 762 good quality Orthopantomograms (OPGs) of 5–15 aged healthy Egyptian children selected from Nile Delta governorates between August 2020 and December 2021. Chronological age (CA) was calculated by subtracting birth date from radiograph date. OPGs were analyzed for N0, S, Xi morphologic variables using Sidexis program after that dental age was calculated using Cameriere’s formula then compared to CA. Multiple linear regression model was used to adapt Cameriere’s formula to construct an Egyptian formula. The same sample was used to verify the new formula accuracy.

Results

A total of 1093 OPGs were collected; 762 OPGs which met inclusion criteria were analyzed. Cameriere’s original formula revealed − 0.59- and − 0.53-year underestimation of females and males dental age (DA) respectively (p < 0.001). Regression analysis using the morphologic variables showed that X4, X7, N0 contributed significantly to CA yielding Egyptian-specific formula. New formula showed − 0.12-year male underestimation and 0.1-year female overestimation (p > 0.05).

Conclusion

Egyptian formula was more accurate than Cameriere’s formula in Egyptian children.

Clinical relevance

Egyptian-specific formula decreases the gap between CA and DA, so a relative approximate age is obtained that helps proper diagnosis and treatment planning for orthodontic and pediatric dentistry problems.

Children and Adolescent Dental Age Estimation by the Willems and Al Qahtani Methods in Surabaya, Indonesia

Objectives

Dental age estimation has been employed in a range of legal operations as well as catastrophe victim identification. Dental age estimation is regarded as an appropriate method for estimating a person's age because there is a high association between age and teeth. This study aims to assess the suitability of the Al Qahtani and Willems dental age estimation approaches for the Indonesian children and adolescent population.

Methods

A total of 150 panoramic radiographs of patients (75 boys and 75 girls, 6-17 years old) were obtained from the Department of Radiology, Airlangga University, Indonesia. One researcher analyzed estimated dental age (EDA) twice in a one-week time-lapse using the Willems and Al Qahtani methods. The statistical analysis of the present study was carried out using IBM® SPSS® Statistics version 25.0 (IBM, Armonk, NY, USA).

Results

The mean of this study's chronological age (CA) was 11.60 ± 3.41. Using the Willems method, the mean difference between CA and EDA for boys and girls was -0.41 ± 0.90. The mean difference between CA and EDA for boys and girls is 0.33 ± 0.61 using the Al Qahtani method.

Conclusions

According to the findings of this investigation, the dental age estimation method proposed by Al Qahtani and Willems can be applied to the population in Surabaya. However, a comprehensive study is required when using this method because the data revealed significant statistical disparities between the two methods.

Applicability of 2 Dental Age Estimation Methods to Taiwanese Population

The aim of this study is to assess the accuracy of Demirjian and Willems dental age estimation methods on a population of 8- to 15-year-old Taiwanese children. A total of 799 digital panoramic radiographs (404 boys, 395 girls) of children aged from 8.00 to 15.99 years are evaluated. All panoramic films are assessed by 2 examiners using Demirjian and Willems methods. We randomly select 48 panoramic films to evaluate the reproducibility of dental age measurements. The intraobserver and interobserver Cohen's kappa values are 0.733 and 0.762, respectively.The difference between chronological age and dental age is calculated for each individual using both methods. The result shows that Demirjian method slightly overestimates the chronological age of children. The mean age difference is 0.12 years for boys (standard deviation [SD], 0.80) and 0.21 years for girls (SD, 0.95). Willems method slightly underestimates the chronological age of children. The mean age difference is -0.22 years for boys (SD, 0.80) and -0.12 years for girls (SD, 0.92).In conclusion, Demirjian and Willems methods are both accurate for assessing dental age in the Taiwan region of China. The mean age differences of both methods are within ±1 year, which is acceptable at forensic odontology level. However, although the discrepancy between chronological age and dental age is frequently observed between -0.5 and 0.5 years in both methods, there is no guarantee it will be accurate for any particular individual, further modifications to both methods are suggested.

Dental age assessment by tooth emergence counts its chronological age predictive value in normal occlusion Bogotanians (mestizos)

Objective: (1) To test Hägg-Taranger's method of dental age assessment (DAA) in Bogotanian children comparing findings by sex with Swedishes' standards and (2) to investigate its chronological age predictive value for identification purposes.Material and methods: Dental age was assessed in 5-14-year-old Bogotanians, 2075 girls and 2032 boys and compared with the method's standards. For statistical analysis, matched-pair signed-rank tests were used, and a regression model was used for investigating value as chronological age predictor from dental age.Results: No significant difference was found between means of dental ages of Bogotanians and Swedishes, except for the lower central incisors' and second molars' emergences. Differences by sex between dental age means were seen at all stages especially, in mixed dentition (p<.01), being Bogotanian girls earlier maturers than boys. The established regression model as chronological age predictor, was tested by the coefficient of determination, which was found r²=0.979 for girls, and 0.957 for boys.Conclusions: Sexual dimorphism in dental age suggests Hägg-Taranger's method for identification by sex at mixed dentition. Additionally, high coefficients of determination show its reliability as chronological age predictor for ages from 5 to 12 years in girls, and to 13 years in boys.

Dental age assessment on panoramic radiographs: Comparison between two generations of young Finnish subjects

Objective

To analyse the accuracy of a meta-analysis-based dental age assessment (DAA) method in Finnish paediatric patients and to compare the dental development between two generations of Finnish children.

Methods

Panoramic radiographs of Finnish Caucasian healthy children from two generations (early: born 1981–1984; subsequent: born 1996–2008) were analysed. All developing teeth on the left maxilla and mandible as well as the third permanent molars were analysed following Demirjian’s classification. For each patient, dental age was calculated and compared with chronological age. Dental maturation patterns between the two groups were compared.

Results

The study included 200 Finnish Caucasian healthy children from two generations (early: aged 7–13 years; subsequent: aged 6–15 years). In the early generation, DAA underestimated the chronological age by a mean of 3.15 years. The underestimation was only 0.11 years in patients < 10 years, but 3.86 years in patients ≥ 10 years. In the subsequent generation, the dental age was overestimated by a mean of 0.34 years; by 0.40 years in patients < 10 years and by 0.08 years in patients ≥ 10 years.

Conclusions

The present DAA method is applicable to current Finnish children. Differences in dental development between two generations of Finnish children were detected.

A Reappraisal of Developing Deciduous Tooth Length as an Estimate of Age in Human Immature Skeletal Remains

This study provides an update on a quantitative method for immature age estimation based on postnatal deciduous mandibular tooth length. Two known sex and age skeletal collections from Western Europe were sampled (n = 97). Linear regression models for age estimated were calculated for each individual tooth, each sex, and sex combined sample using classical calibration. Prediction errors, residuals, and percentage of individuals whose real age fell within the 95% prediction interval were calculated. The teeth which develop earlier in life, the incisors and the first molar, showed the greatest precision, while the canine showed the least. This method has greater applicability to archeological skeletons or to children in developing countries than for use in North American or European forensic contexts. The method can be applied to incomplete or poorly preserved remains of unknown sex, particularly when dental radiographs are not an option or when teeth have been removed from the alveolus or crypt.

Validity and accuracy of three radiographic dental age estimation methods in Brazilians

OBJECTIVE

To validate, analyse accuracy, and construct multiple regression formulae of three age estimation methods - Liliequist and Lundberg, Haavikko, and Mornstad - using mineralization stages of permanent teeth in Brazilians.

METHODS

Panoramic radiographs of 1009 Brazilian children and adolescents (387 males and 622 females) aged 8-15.99 years were analysed using the aforementioned methodologies.

RESULTS

The overall accuracy (absolute difference=AD and dental age-chronological age=DA-CA) of the methods was as follows: Liliequist and Lundberg, AD=0.97 and DA-CA=-0.58; Haavikko, AD=1.42 and DA-CA=-1.35; and Mornstad, AD=2.48 and DA-CA=0.78. After sex-based stratification, the values for males were as follows: Liliequist and Lundberg, AD=0.91 and DA-CA=-0.45; Haavikko, AD=1.80 and DA-CA=-1.75; and Mornstad, AD=2.74 and DA-CA=1.17. In females, the values were as follows: Liliequist and Lundberg, DA=1.01 and DA-CA=-0.67; Haavikko, AD=1.17 and DA-CA=-1.09; and Mornstad, AD=2.31 and DA-CA=0.53. The Liliequist and Lundberg technique predominated, followed by Haavikko and Mornstad when distinction was present between sex and age. Multiple regression formulae were constructed from the data presented for the Liliequist and Lundberg, Haavikko and Mornstad methodologies.

CONCLUSIONS

The validation of the methodologies in the Brazilian population is possible. The Liliequist and Lundberg method most closely represented the Brazilian sample.

A Reappraisal of Developing Permanent Tooth Length as an Estimate of Age in Human Immature Skeletal Remains

This study expands on existing juvenile age prediction models from tooth length by increasing sample size and using classical calibration. A sample of 178 individuals from two European known sex and age skeletal samples was used to calculate prediction formulae for each tooth for each sex separately and combined. Prediction errors, residuals, and percentage of individuals whose real age fell within the 95% prediction interval were calculated. An ANCOVA was used to test sex and sample differences. Tooth length for age does not differ between the samples except for the canine and second premolar, and no statistically significant sex differences were detected. The least prediction error was found in the incisors and the first molar, and the highest prediction error was found in the third molar. Age prediction formulae provided here can be easily used in a variety of contexts where tooth length is measured from any isolated tooth.

Secular trend in the maturation of permanent teeth in a sample of Turkish children over the past 30 years

This study was performed to evaluate the influence of secular trends on dental maturation among Turkish children over the past 30 years. Orthopantomograms of 757 (385 boys, 372 girls) Turkish children born in the 1980s, 1990s, and 2000s were evaluated. Three groups were formed based on decade with five subgroups by age from 9 to 13 years old for each gender. The number of samples in each age group and gender were matched. The mandibular left seven permanent teeth were evaluated based on formation stage to determine the overall dental maturity score. The groups were compared based on decade and gender. The Bonferroni-corrected Mann-Whitney U test and Kruskal-Wallis tests were used for statistical evaluation. Among 11-, 12-, and 13-year-olds born in the 2000s, girls exhibited significantly more mature dentition than did boys (p<0.01, p<0.05, and p<0.05, respectively). Twelve-year-old girls born in the 1990s and 2000s exhibited significantly more mature dentition than did girls born in the 1980s (p<0.01). Girls generally exhibited more mature dentition than boys. No significant positive secular trends in dental maturity were observed from the 1980s through the 2000s. Dental maturation among Turkish children was not affected by a secular trend.

Dental age assessment on panoramic radiographs in a Swiss population: a validation study of two prediction models

OBJECTIVES

Dental age assessment methods are widely used for age estimation. This study aimed to analyse the accuracy of a meta-analysis method to estimate dental age in Swiss individuals and to detect potential limitations of the method. Precision of repeated tooth staging using Demirjian's classification on maxillary and mandibular teeth was also assessed.

METHODS

Panoramic radiographs of 50 Swiss white healthy children were analysed. Developing teeth on the left maxilla and mandible and all third permanent molars were staged following Demirjian's classification. Dental age was calculated for each subject, using a random effects model and a fixed effect model, and compared with chronological age.

RESULTS

The mean error of the dental age ranged between -3 and +1 months for both the calculation models. Dental age calculated with the fixed effect model overestimated the age of the subjects (average + 0.10 y, ranging from -1.95 y to +2.16 y) compared with their chronological age, whereas the random effects model underestimated the age (average -0.32 y, ranging from -2.24 y to +1.61 y).

CONCLUSIONS

Demirjian's method allowed a precise repeated staging of maxillary and mandibular developing teeth. For both calculation models, dental age correlated well, on average, with chronological age of Swiss subjects younger than 12 years. The random effects model showed a better accuracy for these subjects than the fixed effect model. However, both models underestimated the chronological age in subjects older than 12 years.

Forensic radiology in dentistry

Radiography can play an important part in forensic odontology, mainly to establish identification. This may take the precise form of comparison between antemortem and postmortem radiographs. Radiographs may also be taken to determine the age of a minor victim and even help in the assessment of the sex and ethnic group. Comparable radiographs are an essential factor to confirm identification in a mass disaster.

Estágio de mineralização dos terceiros molares e sua relação com a idade cronológica: uma amostra da população do Centro-Oeste do Brasil

INTRODUÇÃO: Nos últimos anos, alguns estudos foram conduzidos com o objetivo de avaliar a aplicabilidade da análise de desenvolvimento dos terceiros molares na estimativa da idade humana. No entanto, há escassez de trabalhos em amostras populacionais da região Centro-Oeste do Brasil.OBJETIVO: Avaliar a relação entre estágio de desenvolvimento dos terceiros molares inferiores e a idade cronológica de indivíduos da região Centro-Oeste do Brasil.MATERIAL E MÉTODO: Trata-se de um estudo observacional transversal, com uma amostra constituída por 120 prontuários de pacientes entre 5 e 22 anos de idade, dos gêneros masculino e feminino, atendidos entre os anos de 2007 e 2012 na nossa instituição. O estágio de desenvolvimento dos terceiros molares inferiores foi avaliado pelo método descrito por Nolla e relacionado à idade cronológica do indivíduo por meio de regressão linear, sendo considerados significantes valores de tendência linear entre 0 e 1.RESULTADO: Pode-se observar que tanto a amostra composta por pacientes do gênero masculino (R2 = 0,7495) quanto do feminino (R2 = 0,8507) apresentaram correlação linear entre o estágio de desenvolvimento dos terceiros molares inferiores e a idade cronológica. Notou-se, ainda, que os estágios de desenvolvimento coincidiram com idades semelhantes em ambos os gêneros.CONCLUSÃO: Há relação entre a idade cronológica e o estágio de desenvolvimento dos terceiros molares inferiores na amostra estudada. Estes dados sugerem que este tipo de análise deve ser individualizada, de acordo com as características populacionais da região.

Digital radiographic evaluation of hand-wrist bone maturation and prediction of age in South Indian adolescents

BACKGROUND

In the growing years, indicators of the level of maturational development of the individual provide the best means for evaluating biologic age and the associated timing of skeletal growth. The relative stage of maturity of a child may be determined by comparing the child's hand-wrist radiograph to the known standards of skeletal development.

AIMS AND OBJECTIVES

In this study, we assessed various levels of skeletal maturation and also identified the relationship between chronological age (CA) and maturation stage using the hand-wrist radiographs in adolescents of Indian origin.

MATERIALS AND METHODS

Three hundred and thirty hand-wrist digital radiographs of individuals aged 8 to 18 years were evaluated for skeletal maturity levels using Fishman's method. The data was analysed using the SPSS software package (version 12, SPSS Inc., Chicago, IL, USA). Regression analysis was performed for calculating bone age of both males and females. Spearman's rank-order correlation coefficients were estimated separately for males and females to assess the relation between CA and maturation level.

RESULTS

An association between skeletal maturation indicator stages and CA (r = 0.82) was significant. Interestingly, female subjects were observed to be advanced in skeletal maturity compared to males. Regression equations were derived to calculate bone age in males, females and the whole sample.

CONCLUSION

The results of this study showed significant association between hand-wrist skeletal maturation levels and CA. Digital radiographic assessment of hand-wrist skeletal maturation can be used as a better choice for predicting average bone age of an individual because of its simplicity, reliability and lesser radiation exposure.

Age assessment using the Greulich and Pyle method on a heterogeneous sample of 300 Italian healthy and pathologic subjects

The exponential growth of the illegal immigration phenomenon, the requests for asylum, and the increasing number of migrant settlements on Italian territory have strong repercussions on the legal system. One important aspect of this problem is age assessment. In the case of living individuals, identification may be focused on ascertaining their age, more directly if they can attest their age but are not registered (foreigners who claim to be minors or under 14 years of age). These have entered our country as illegal immigrants and have an interest in declaring a younger age (as a minor or under 14) rather than their true age because they can obtain the benefits specifically provided by Italian law for such categories. Since the most frequently used method in age assessment is the Greulich and Pyle Atlas, the objective of this study was to evaluate the consistency and accuracy of the method on a sample of Italian teenagers, in order to ascertain whether or not the Atlas is suitable for the purpose, especially in the critical threshold between 14 and 18 years of age. A total of 300 radiographs of the left wrist and hand of individuals between 10 and 20 years of age were obtained from the outpatient Pediatric Radiology Department of the Papa Giovanni XXIII Hospital in Bari. The results showed that the Greulich and Pyle Atlas, used on the Italian population, provide a good match with the chronological age, showing no statistically significant differences. The Greulich and Pyle Atlas is usable on the Italian population since there were no significant differences in skeletal age determination with this method as compared to the chronological age; however, one must allow for a possible standard deviation equal to more or less 13 months.

Medidas lineares dos estágios de desenvolvimento da dentição permanente humana usando Tomografia Computadorizada de Feixe Cônico: um estudo preliminar

OBJETIVO: determinar as medidas lineares dos estágios de desenvolvimento da dentição permanente humana, usando tomografia computadorizada de feixe cônico (TCFC). MÉTODOS: este estudo foi desenvolvido a partir de bancos de dados de clínicas radiológicas privadas, envolvendo 18 pacientes (13 do sexo masculino, 5 do sexo feminino, com idades variando entre 3 e 20 anos). As imagens das TCFC foram obtidas por meio do sistema i-CAT e medidas com uma função específica do programa desse mesmo sistema. Duzentos e trinta e oito dentes foram analisados, em diferentes estágios de desenvolvimento, nos planos coronal e sagital. O método foi baseado na delimitação e mensuração das distâncias entre pontos anatômicos correspondentes ao desenvolvimento das coroas e raízes dentárias. A partir dos valores obtidos, pôde-se desenvolver um modelo quantitativo para se avaliar os estágios inicial e final de desenvolvimento para todos os grupos dentários. RESULTADOS E CONCLUSÕES: as medidas obtidas dos diferentes grupos dentários estão de acordo com as estimativas das investigações publicadas previamente. As imagens por TCFC dos diferentes estágios de desenvolvimento podem contribuir no diagnóstico, planejamento e resultado dos tratamentos em diversas especialidades odontológicas. As dimensões das coroas e das raízes dentárias podem ter importantes aplicações clínicas e em pesquisas, constituindo uma técnica não invasiva que contribui com estudos in vivo. Entretanto, mais estudos são recomendados a fim de minimizar possíveis variáveis metodológicas.

Dental Age Assessment: a comparison of 4- to 24-year-olds in the United Kingdom and an Australian population

BACKGROUND

The physiological age of a person is determined by the degree of maturation of the different tissue systems. Children of the same chronological age (CA) can demonstrate different degrees of maturation. Dental age (DA) is based on the maturation of teeth. Tooth formation is a continuous process, where the developmental stages of the tooth can be sequenced and defined depending on the degree of mineralization. These stages can be visualized on a dental panoramic tomograph (DPT).

AIM

The aim of this study was to use a new method of Dental Age Assessment (DAA) to compare a United Kingdom (UK) and an Australian (AUS) population.

DESIGN

The DPTs used are from the archives of the Westmead Centre for Oral Health (Westmead, Australia) and the King's College London Dental Institute. From the preliminary sample of 89 DPTs from each population, 77 were suitable for use as matched pairs. The radiographic technique used was developed by Demirjian and describes eight stages of tooth development. This was used in combination with numerical data derived from a meta-analysis of a single UK subject.

RESULTS

A significant difference was shown between the CA and DA of the AUS patients. The AUS patients were also shown to have a significant 0.82 years delay in their DA compared to the UK patients. The findings indicate a difference in AUS compared to UK patients. These results indicate the need to develop a reference data set for the AUS population for DAA.

CONCLUSIONS

This research is of significance in a number of clinical disciplines and can also be used to assist in age determination of subjects of unknown birth date to assist in forensic dentistry or social deliberations.

Comparison of the three age estimation methods: which is more reliable for Turkish children?

BACKGROUND

Three atlases-the GOK, the Greulich-Pyle (GP), and the Tanner-Whitehouse (TW3)-are used frequently for age determination in Turkey. The purpose of this study was to evaluate the applicability of these three methods related to the skeletal age assessment for Turkish adolescents.

MATERIALS AND METHODS

The conventional roentgenograms of the left hands and wrists, elbows, shoulders, and pelvises of 333 healthy Caucasian children (164 females, 169 males) who fit the study and the criteria of each atlas were obtained. The mean differences (+/- standard deviation [S.D.] in years) between the chronologic age (CA) and the skeletal age (BA), which were obtained by using each age estimation method, were calculated and tested using t-test.

RESULTS

For girls, the most accurate method was the TW3 (mean differences (d): -0.21 (p<0.05)), following by the GP (d: 0.66 (p<0.001), and the GOK (d: 2.99 (p<0.001)). For boys, the most accurate method was the GP (d: -0.02 (p>0.05)), followed by the TW3 (d: -0.18 (p<0.05)) and GOK (d: 1.05 (p<0.001)).

DISCUSSION AND CONCLUSIONS

Results show that the TW3 (for girls) and the GP (for boys) methods are more appropriate than the GOK atlas for estimating the BA. GOK could be used for boys aged 11-14 years but it should not be used for girls.

Accuracy of age estimation in children using radiograph of developing teeth

The aims of this study were: first, to determine the accuracy of the Cameriere method for assessing chronological age in children based on the relationship between age and measurement of open apices in teeth and, second, to compare the accuracy of this method with the widely used Demirjian et al. method and with the method proposed by Willems et al. Orthopantomographs taken from white Italian, Spain and Croatian children (401 girls, 355 boys) aged between 5 and 15 years were analysed following the Cameriere, Demirjian and Willems methods. The difference between chronological and dental age was calculated for each individual and each method (residual). The accuracy of each method was assessed using the mean of the absolute values of the residuals (mean prediction error). Results showed that the Cameriere method slightly underestimated the real age of children. The median of the residuals was 0.081 years (interquartile range, IQR=0.668 years) for girls and 0.036 years for boys (interquartile range, IQR=0.732 years). The Willems method showed an overestimation of the real age of boys, with a median residual error of -0.247 years and an underestimation of the real age of girls (median residual error=0.073 years). Lastly, the Demirjian method overestimated the real age of both boys and girls, with a median residual error of -0.750 years for girls and -0.611 years for boys. The Cameriere method yielded a mean prediction error of 0.407 years for girls and 0.380 years for boys. Although the accuracy of this method was better for boys than for girls, the difference between the two mean prediction errors was not statistically significant (p=0.19). The Demirjian method was found to overestimate age for both boys and girls but the mean prediction error for girls was significantly greater than that for boys (p=0.024), and was significantly less accurate than the Cameriere method (p<0.001). The Willems method was better than that of Demirjian (p=0.0032), but was significantly less accurate than that of Cameriere (p<0.001).

Accuracy of developing tooth length as an estimate of age in human skeletal remains: The deciduous dentition

Dental age assessments are widely used to estimate age of immature skeletal remains. Most methods have relied on fractional stages of tooth emergence and formation, particularly of the permanent dentition, for predicting the age of infants and very young children. In this study, the accuracy of regression equations of developing deciduous tooth length for age estimation (Liversidge et al.) is tested on a sample of 30 Portuguese subadult skeletons of known age at death. Overall the method shows high accuracy and the average difference between estimated and chronological age is between 0.20 and -0.14 years when using single teeth, and 0.06 years, when using all available teeth. However, there is a tendency for the deciduous molars to provide overestimates of chronological age. Results show that age estimates can be obtained within +/-0.10 years with a 95% confidence interval when several teeth are used. Overall between-tooth agreement in age estimates decreases with increasing age but there is less variability of estimates with more teeth contributing to overall mean age. One seemingly limitation of this method may be the fact that it was developed by combining the maxillary and mandibular teeth. The other is related to the accuracy with which radiographic tooth length can be used as a valid surrogate for actual tooth length. Nevertheless, the advantages of this metric method surpass the limitations of chronologies based on stages of dental development.

The measurement of open apices of teeth to test chronological age of over 14-year olds in living subjects

Age determination in living subjects is a problem of increasing interest in our community, due to the increasing numbers of individuals without identification papers, who have immigrated illegally or committed crimes, and for whom it is necessary to verify whether they have reached the age of 14 years in order to be charged legally. Although the most widespread methods for age estimation refer to skeletal or dental analysis, these methods do present some drawbacks for identification of the age of 14. The aim of the present study is to discriminate between children who are or are not 14 years of age or older by measuring the open apices of teeth. We evaluated the OPGs of 447 persons aged between 12 and 16 years, of Italian, Croatian and Slovenian nationality. For each individual, dental maturity was estimated using the number of the seven left permanent mandibular teeth with root development complete, and normalized measurement of the open apices of the third molar. The results revealed that an individual is considered to be 14 years of age or older if all seven left permanent mandibular teeth have closed apices and the normalized measurement of open apices of the third molar is lower than 1.1.

A Test of the Differential Accuracy of the Maxillary Versus the Mandibular Dentition in Age Estimations of Immature Skeletal Remains Based on Developing Tooth Length

Liversidge and colleagues developed a method for predicting the age of immature skeletal remains based on the length of developing teeth. This quantitative method combines dental data from both jaws, except for the permanent lateral incisor, and because there are reasons to suspect that these two types of data are not identical and should not be combined, it raises concerns regarding the accuracy of the technique when applied differently to each jaw. In this study, the differential accuracy of the method was test when applied to the maxillary and mandibular dentition. The test sample is comprised of 57 Portuguese subadult skeletons of known age at death. Results suggest an overall high consistency between estimates obtained from both jaws, but for the permanent dentition only. In the deciduous dentition the age estimates obtained from the maxillary teeth tend to be greater than the age estimates obtained from the mandibular pair, and the differences are significant for the incisors and canine. Additionally, ages obtained from the maxillary deciduous canine also differ significantly from true chronological age. In the permanent dentition there were no differences between the ages provided by both jaws but both the maxillary and mandibular second molars show a significant tendency to underestimate true chronological age. Although this study cannot validate completely the method presented by Liversidge and colleagues, it does provide an important test to its accuracy and calls for further research into its overall performance, particularly with respect to the results obtained from both jaws.

Recommendations for the forensic diagnosis of sex and age from skeletons

In both diagnostic fields a two-stage strategy is recommended: to first use "field" methods that are quick and easy but more imprecise and then "laboratory" methods that are time consuming but more precise. In preparing skeletal work, individuality of a skeleton should be checked, traces of diseases sought and time since death assessed. For sexing non-adults, the field methods are tooth mineralisation, long bone length and a few morphological skull and pelvis characteristics, for adults it is the morphology of pelvis and skull, and for both age groups the advanced laboratory method is molecular biology. For ageing non-adults the methods are mineralisation of teeth, long bone length and epiphysis development. For ageing adults the advanced laboratory method is aspartic acid racemisation. Less accurate laboratory methods are cement ring counts and histology of bones and teeth. Quick morphological methods using the pubic symphysis and other traits in combinations follow. Finally, cranial sutures and tooth number give a quick and rough impression. For the selection of a method and the assessment of its value the stochastic error produced for the reference sample is the decisive criterion; it should also be used to assess the reliability of a single diagnosis. Prerequisites for all work with skeletons are not only a complete knowledge of the relevant biology as well as specific techniques but also initial detailed instructions and with forensic applications, personal experience.

Usefulness of Combining Clinical and Radiological Dental Findings for a More Accurate Noninvasive Age Estimation

The aim of this study was to establish correlations of clinical and radiological dental findings, alone or in combination, with chronological age in adults. Dental findings and orthopantomograms of 984 patients (aged 20-60 years; 524 females/460 males) were analyzed. DMF-T index and distance (alveolar bone level, ABL) between cemento-enamel junction and alveolar bone margin were recorded. Additionally, clinical and radiological findings at each tooth crown and root were collected according to the actual status of destruction and restoration, and a total score for each dentition (TSD) was calculated. After univariate correlation analysis, correlation coefficients for ABL and TSD were improved by using square root (sqrt). However, the determination accuracy was still not satisfactory; 90% of the residuals were in the range of about +/-10. The present study showed that clinical and radiological dental findings could not be used, not even in combination, for accurate age estimation as a single method, but that they could support other methods.

Epidermolysis bullosa and dental developmental age

OBJECTIVES

The dental development of permanent mandibular teeth in a small group of children with dystrophic epidermolysis bullosa (DEB) was assessed from radiographs and compared to a healthy, age-and-sex-matched control group.

METHODS

This was a retrospective radiographic cross-sectional study. The sample consisted of a group of 44 children aged between 4 and 15 years with DEB and healthy, age-and-sex-matched controls. Two quantitative methods of assessing tooth formation were used: (1) a combination of information about tooth length and apex width; and (2) the use of tooth length to predict age. Panoramic radiographs were digitized in order to determine tooth length and apex width. Dental age was calculated, and the difference with real age was tested with Student's t-test.

RESULTS

The dentition of both the DEB and control groups was slightly delayed. Using the first method, the delay was 0.34 +/- 0.87 years for the DEB group and 0.29 +/- 0.97 years for the control group. Using the second method, the delay was 0.49 +/- 1.18 years for the DEB group and 0.23 +/- 0.62 years for the control group. This delay was not statistically significant for either method.

CONCLUSIONS

The dental formation of permanent mandibular teeth in the group of children with DEB was not significantly different to that found in the control group.