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

Validity of the Demirjian Method for Dental Age Estimation in Romanian Children

Dental age assessment is useful in various medical fields. The Demirjian method for dental age estimation is one of the most widely used in the field of pediatric dentistry. The aim of this study was to verify the accuracy of the Demirjian method in determining age in a sample of girls and boys from Oradea, Romania. This retrospective and radiographic study was based on the evaluation of 1006 panoramic radiographs, belonging to 1006 patients (431 boys and 575 girls) with ages between 3 and 13.9 years from the city of Oradea, Romania. They were collected from three private dental practices from Oradea and were analyzed between 1 September 2021, and 10 November 2021. The patients were distributed into 11 age groups, each group spanning over one year (e.g., 3−3.9, 4−4.9). For the assessment of dental age, the Demirjian method was used, which is based on the evaluation of the developmental stages of the lower left permanent teeth. The mean chronological age of the patients was 9.496 ± 2.218 years, and the mean dental age was 10.934 ± 2.585 years. The overestimation of dental age was obtained in all age groups for the entire sample. As such, dental age was higher than chronological age, with values varying from 0.34 years in the 3−3.9 years age group to 1.7 years in the 10−10.9 years age group. In girls, dental age was higher than chronological age, with values varying from 0.46 years in the 3−3.9 years age group to 1.73 years in the 11−11.9 years age group, while in boys, the values varied from 0.15 years in the first age group to 2.02 years in the 10−10.9 years age group. The comparison of the differences between chronological age and dental age according to the gender of the patients revealed that the distribution of the differences was nonparametric in both groups according to the Shapiro−Wilk test (p < 0.05). The differences between the groups were not significant according to the Mann−Whitney U test. However, larger differences were identified for boys (1.46 years) than girls (1.417 years), with an overestimation of the dental age. The Demirjian method overestimated the age of the children included in the investigated sample, with different values for the different age groups investigated, and requires adaptations.

Assessment of dental age estimation methods applied to Brazilian children: a systematic review and meta-analysis

OBJECTIVES

To review the scientific literature of studies on dental age estimation methods applied to Brazilian children.

METHODS

A systematic literature review was designed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines and registered in PROSPERO (CRD42020136170). Six scientific databases were used as primary search sources (PubMed, Scopus, LILACS, SciELO, Embase and Web of Science) and two databases (Open Grey and Open Thesis) were searched to partially select the "grey literature." Only cross-sectional studies were included. The risk of bias was assessed by means of Joanna Briggs Institute Critical Appraisal Tools for Systematic Reviews. The standardized mean difference (SMD) between the estimated dental and chronological ages was meta-analysed via random effects model.

RESULTS

The search resulted in 2,527 studies, from which 13 met the eligibility criteria. Out of the eligible studies, 76.92% had low risk of bias and high methodological quality. Ten studies provided proper information to be included in the meta-analysis.The methods and their SMD between estimated and chronological ages were: Willems'=0.05, Lilequist and Lundberg's = -0.11, Nolla's = 0.22, Mornstad's = 0.27, Cameriere's = -0.31, Demirjian's = 0.74 and Haavikko's = -0.87.

CONCLUSION

Although originally trained in populations worldwide, most of the international methods for radiographical dental age estimation had optimal performance in Brazilian children.

Mandibular Measurements for Sex and Age Estimation in Brazilian Sampling

Objective

The present study aimed to evaluate the possibility of sex and age estimation in a Brazilian sample, using the following five mandibular measurements: coronoid height, gonial angle, bigonial distance, ramus height, maximum length.

Materials and methods

In total, 103 mandibles were measured, 53 female and 50 male, grouped according to the age in 5 different groups. Two different observers performed all these measurements. For statistical analysis, one-way ANOVA was used with a significance level of 5% to verify if the mandibular measurements were related to age. The Student t-test was used for comparisons between the sex samples. Eighty three samples were used to develop a logistic regression model. The intra-observer and inter-observer differences were evaluated using the Kappa coefficient.

Results

The sex differences were statistically significant in all the variables, and all of them were larger in men, apart from the variable related to the gonial angle (GA), which was larger in women. For the logistic regression formula, the variables used were: bigonial distance and mandibular ramus, with 90% accuracy. For age, the measurements did not show a pattern. The inter and intra-observer values were greater than 0.85.

Conclusion

In conclusion, it is possible to estimate sex using mandibular measurements, but it is not recommended to use these measurements for age estimation.

Dental development in patients with and without unilateral cleft lip and palate (UCLP): a case control study

OBJECTIVE

To evaluate if the presence of unilateral cleft lip and palate (UCLP) causes delay in dental age and tooth development.

MATERIALS AND METHODS

Panoramic radiographs of 189 non-syndromic UCLP patients, aged from 6 to 20 years, were collected. Two measures of tooth development were examined: dental maturity scale for the seven left mandibular teeth (dental age-DA) and the degree of each tooth development (developmental score-DS). All the teeth except third molars were staged according to the Demirjian's method. The data of the cleft group were compared with a control group matched for age and gender, based on the findings observed in other 189 panoramic radiographs.

RESULTS

At all ages, DA was lower in the UCLP group, but not always significantly; the highest difference was - 1.411 for females at 13 years old and - 0.776 for males at 12 years old. DS of all teeth was significantly lower in the UCLP group, at all ages under 17 in females, and at all ages under 18 in males. In UCLP group, tooth development was more delayed in the maxilla compared with the mandible. No evidence of a slower development at the cleft side compared with the non-cleft side was highlighted.

CONCLUSIONS

Significant lower dental development was observed in UCLP patients compared with control ones by using DS and DA indexes.

CLINICAL RELEVANCE

These findings can help the clinicians in establishing a proper orthodontic and surgical diagnosis and treatment planning in UCLP patients and for forensic age estimation's purposes.

A new model of classification of third molars development and its correlation with chronological age in a Brazilian subpopulation

The present study correlated the mineralization of third molars to chronological age using a modified classification based on Demirjian's stages in a Brazilian subpopulation and compared with the original classification. A total of 1082 patients with age ranging from 6 to 26 years were included in the sample, with at least one third molar on panoramic radiographs. The third molars were classified according to the original Demirjian classification (8 stages) and a new model based on the Demirjian method, where the original stages were grouped into four stages: AB-enamel mineralization; CD-crown dentin mineralization; EFG-root formation; and H-complete development. Statistical analyses were performed by Kruskal-Wallis/Dunn tests (α = 0.05) and the multinomial logistic regression model. Data were analyzed according to percentiles for the probability of an individual being over 18 years old. The mean ages of the stages in both classifications did not present a significant difference between superior and inferior arches (p < 0.05). The differences in mean ages between all the stages of mineralization were statistically significant (p < 0.001) only for the 4-stage classification. Males attained root formation and complete formation earlier than females (p < 0.05) in the 4-stage classification. The modified classification system showed dependence between chronological age and mineralization stages of third molars, simplifying the age estimation process. At stage H, females present a 95.7% chance of being over 18, while for males, this probability is 89.6%. This modified classification system simplifies the dental age estimation process based on third molars and can be used as a reference for future studies.

A method of estimating age of undocumented children and young adults of different socioeconomic status in Cambodia

A growing number of Cambodian children without legal documentary evidence of date of birth are vulnerable to exploitation. This study aimed to evaluate the applicability of southern Chinese reference dataset for dental age estimation on Cambodian children and young adults of different socioeconomic status. Dental panoramic tomographs (DPT) of 371 Cambodian children and young adults belonging to lower and higher socioeconomic status (SES) groups were analyzed. All the left maxillary and mandibular permanent teeth including the third molars were scored based on Demirjian's classification of tooth development stages. Chronological age (CA) was calculated from the date of birth and date of exposure of radiograph. The mean age of attainment for each stage of development was obtained from the southern Chinese reference dataset. Dental age (DA) was calculated by averaging the mean age scores for all the teeth. Paired t-test and correlation analysis were conducted to measure associations between the chronological age and the dental age for males and females in the lower and higher socio-economic status groups. Underestimation of age was observed in both SES groups using the southern Chinese reference dataset. For the higher SES group, the difference between the chronological and dental age (CA-DA) was 0.26 years for females and 0.11 years for males. The difference was statistically significant only in females (p < 0.05). In the low SES group, the results showed a difference of 0.07 years in females and 0.01 years in males; the differences were not statistically significant in both sexes (p > 0.05). A strong correlation was observed between the CA and DA in both sex and SES groups ranging from 0.969 to 0.988 (p < 0.05). The southern Chinese dental reference dataset can be used to estimate the age of undocumented Cambodian male and female children and young adults of both higher and lower SES.

Age and sex estimation based on pulp cavity volume using cone beam computed tomography: development and validation of formulas in a Brazilian sample

OBJECTIVES

To develop and validate formulas for age and sex estimation based on the pulp cavity volume of teeth using cone beam CT.

METHODS

The sample was composed of 116 cone beam CT scans from Brazilian individuals of both sexes, ranging in age from 13 to 70 years. A total of 232 teeth (upper central incisors and canines) were evaluated. Two calibrated examiners determined pulp cavity volumes using the ITK-SNAP software. Pearson's correlation test was used to assess the correlation between chronological age and pulp volume. Linear and logistic regression models were developed for age and sex estimation, respectively, and were validated in another sample of 72 teeth.

RESULTS

Pearson's correlation coefficients between age and pulp volume were negative and significant (p < 0.0001) for both teeth (r = -0.8782 for central incisors and r = -0.8738 for canines). The age estimation formulas showed good determination coefficients (adjusted R² = 0.7614 to 0.8367). For sex estimation, when the age was known, the coefficients were also good (adjusted R² = 0.649 to 0.812). However, when the age was unknown, the coefficients of the sex estimation formulas were low (adjusted R² = 0.047 to 0.393). Validation showed high accuracy of age estimation in individuals older than 35 years, as well as high accuracy of sex estimation when the age was known.

CONCLUSIONS

Our formulas provided excellent results and can be applied to the Brazilian population. The best results were observed for age estimation in females and for sex estimation when the age was known.

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.

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.

Northern Chinese dental ages estimated from southern Chinese reference datasets closely correlate with chronological age

While northern and southern Chinese are genetically correlated, there exists notable environmental differences in their living conditions. This study aimed to evaluate validity of the southern Chinese reference dataset for dental age estimation applied to northern Chinese. Dental panoramic tomographs of 437 northern Chinese aged 3 to 21 years were analysed. All the left maxillary and mandibular permanent teeth plus the 2 third molars on the right side were scored based on Demirjian's classification of tooth development stages. Mean and standard error of dental age were obtained for each tooth development stage, followed by random effect meta-analysis for mean dental age estimation. Validity of the method was examined through measures of agreement (95% limits of agreement, standard error of measurement, and Lin's concordance correlation coefficient) and measure of reliability (Intraclass correlation coefficient). On average, the estimated dental age overestimated chronological age by only around 1 month in both females and males. The Intraclass correlation coefficient values were 0.99 for both sexes, suggesting excellent reliability of the method. Reference dataset for dental age estimation developed on the basis of southern Chinese was applicable for use among the northern Chinese.