Developmental Stages Of Third Molars Research Articles

Correlation of Left Mandibular Third Molar Development and Chronological Age

The aim of this study is to evaluate the development of the left mandibular third-molar development with modified Demirjian method and its relation to chronological age. A total of 1653 digital panoramic radiographs of healthy individuals aged between 7 and 23 years who visited Yonsei University Dental hospital were selected. The developmental status of the left mandibular third molars was assessed using dental maturity scoring proposed by Demirjian et al. The mean age of the first appearance of mineralization, complete crown formation, and complete root formation were around 9, 14, 21 years respectively. Statistically significant differences between males and females in the development stage of D and G were revealed that crown formation and root length completion were attained earlier in males than in females. There was significant positive relationship between age and third molar development in both sexes, and new formula was presented to estimate age of children and adolescents based on their developmental stages of third molars. In this study, the use of left mandibular third molar as a developmental marker is appropriate, and age estimation can be attained with dental maturity stage.

Age estimation in the living: Transition analysis on developing third molars

A radiographic assessment of third molar development is essential for differentiating between juveniles and adolescents in forensic age estimations. As the developmental stages of third molars are highly correlated, age estimates based on a combination of a full set of third molar scores are statistically complicated. Transition analysis (TA) is a statistical method developed for estimating age at death in skeletons, which combines several correlated developmental traits into one age estimate including a 95% prediction interval. The aim of this study was to evaluate the performance of TA in the living on a full set of third molar scores. A cross sectional sample of 854 panoramic radiographs, homogenously distributed by sex and age (15.0–24.0 years), were randomly split in two; a reference sample for obtaining age estimates including a 95% prediction interval according to TA; and a validation sample to test the age estimates against actual age. The mean inaccuracy of the age estimates was 1.82 years (±1.35) in males and 1.81 years (±1.44) in females. The mean bias was 0.55 years (±2.20) in males and 0.31 years (±2.30) in females. Of the actual ages, 93.7% of the males and 95.9% of the females (validation sample) fell within the 95% prediction interval. Moreover, at a sensitivity and specificity of 0.824 and 0.937 in males and 0.814 and 0.827 in females, TA performs well in differentiating between being a minor as opposed to an adult. Although accuracy does not outperform other methods, TA provides unbiased age estimates which minimize the risk of wrongly estimating minors as adults. Furthermore, when corrected ad hoc, TA produces appropriate prediction intervals. As TA allows expansion with additional traits, i.e. stages of development of the left hand-wrist and the clavicle, it has a great potential for future more accurate and reproducible age estimates, including an estimated probability of having attained the legal age limit of 18 years.

Developmental Stages of Third Molars in 16- to 22-year-old Patients Referred to a Clinic in Rafsanjan, Iran using Demirjian and Modified Gleiser and Hunt Methods

Developmental Stages of Third Molars in 16- to 22-year-old Patients Referred to a Clinic in Rafsanjan, Iran using Demirjian and Modified Gleiser and Hunt Methods

Radiographic evaluation of third molar development in 6- to 24-year-olds.

PurposeThis study investigated the developmental stages of third molars in relation to chronological age and compared third molar development according to location and gender.Materials and MethodsA retrospective analysis of panoramic radiographs of 2490 patients aged between 6 and 24 years was conducted, and the developmental stages of the third molars were evaluated using the modified Demirjian's classification. The mean age, standard deviation, minimal and maximal age, and percentile distributions were recorded for each stage of development. A Mann-Whitney U test was performed to test the developmental differences in the third molars between the maxillary and mandibular arches and between genders. A linear regression analysis was used for assessing the correlation between the third molar development and chronological age.ResultsThe developmental stages of the third molars were more advanced in the maxillary arch than the mandibular arch. Males reached the developmental stages earlier than females. The average age of the initial mineralization of the third molars was 8.57 years, and the average age at apex closure was 21.96 years. The mean age of crown completion was 14.52 and 15.04 years for the maxillary and the mandibular third molars, respectively.ConclusionThe developmental stages of the third molars clearly showed a strong correlation with age. The third molars developed earlier in the upper arch than the lower arch; further, they developed earlier in males than in females.

Radiographic Evaluation of Developmental Stages of Third Molar in Relation to Chronological Age as Applicability in Forensic Age Estimation

Objectives: The need for age estimation is increasing day by day; difficulty in human age estimation after 14 years of age has greatly shifted the focus on third molar. Radiographic evaluation of presence, position and degree of third molar formation can be utilized in forensic age estimation. The present study aimed to evaluate the development of third molar in relation to chronological age. Methods: The present study included sample of 479 subjects in the age range 5-30 years, for each subject,orthopantomograph was taken. To assess the developmental stages of third molars; the staging system described by Nolla [1] CM was used. Results: Overall, no significant differences were observed in mean ages at which the developmental stages were reached in all four third molars. The absence of crypt was observed more for maxillary third molars, contrarily, stages 1,2,3 were reached earlier in mandibular third molars. In case of presence of four completely developed third molars in a subject, the probability of an individual to be older than 18 years of age was 94.35% for females and 95.23% for males. Conclusion: Third molar teeth are well known for their variability in development, eruption pattern, size, contour and relative positions as compare to other teeth. In spite of variations, third molars are still at the centre of medicolegal interest; and its significance in age determination is justified as no other reliable age indicator is available to determine the age in adults. Besides, it will help to separate adolescents from adults as jurisprudence differs for juvenile detainees.

Radiographic correlation of dental and skeletal age: Third molar, an age indicator

Background:Age estimation plays a great role in forensic investigations, orthodontic and surgical treatment planning, and tooth transplantation. Teeth offer an excellent material for age determination by stages of development below the age of 25 years and by secondary changes after the age of 25 years. Third molar is often not included for this purpose due to its notorious developmental patterns. The aim of this study was to evaluate the development of third molar anlage in relation to skeletal maturities and the chronological age.Materials and Methods:One hundred and fifty-six young individuals, 78 males and 78 females, were selected. The stages of development of all the third molars in every individual were determined from panoramic radiographs. The skeletal development was assessed using hand wrist radiographs. Data were analyzed statistically for mean value, standard deviation and the relationship between the recorded characteristics.Results:A strong correlation was found between third molar development and skeletal maturity (in males: r=0.88, P<0.001; in females: r=0.77 for maxillary third molar and 0.89 for mandibular third molar, P<0.001).Conclusion:Hence, it is concluded that a strong correlation exists between chronological age, developmental stages of third molars and maturation of epiphyses of hand. Any of the three parameters could be used for the assessment of other maturities.

Third molar development in relation to chronological age in Romanian children and young adults

Examination of the developmental stage of third molars using orthopantomograms can be a useful tool for chronological age determination in the field of legal and forensic medicine. The aim of this study was to assess third molar third molar developmental stages in a sample of Romanian population, to determine chronologic age estimates based on developmental stages, to compare third molar development by sex, age and location. Orthopantomograms of 250 Romanian patients, from the Department of Orthodontics from Universitary Hospital “Sf. Spiridon” Iasi, aged between 11-25 years old, were examined and third-molar developmental stages were evaluated based on Nolla’s classification. Linear regression analysis was performed to correlate third molar development and chronological age, and other statistical analyses were performed to determine relation between sex, age and location. Results showed a strong correlation between age and molar development (r2 = 0.93 and r2 =0.95 for males in the upper and lower jaw and r2 = 0.92 and r2 = 0.94 for females). Males achieve third molar development earlier than females and upper third molars exhibit a greater degree of development than lower third molars at the same chronological age.

Orthopantomography and Age Determination Using Third Molar Mineralization in A Sample of Egyptians

In the last decade, the number of unidentified cadavers and cases lacking age documentation and therefore requiring age determination has increased. Dental age determination still represents today the most sensitive mean. In the age span of 15-26 years of age the wisdom teeth represent the only teeth still in development and thereby very important for dental age assessment. So, the aim of the present investigation was to detect the chronological age of an individual based on the dental developmental stages of third molars proposed by Demirjian et al. (1973). In this study 380 orthopantomograms of Egyptian patients (214 males and 166 females) with known age and sex were selected for the study. Patients' age ranged from 8 to 26 years. X rays were examined by the second author (N.A.A.), the developmental stage of third molars in both upper and lower arches were detected using method of Demirjian et al. (1973). Data were gathered and SPSS was used for statistical processing. The mean values and standard deviation (SD+) were determined for the ages of respective mineralization stages of each of the four wisdom teeth. Further statistical analysis was performed in order to obtain multiple regression formulae for dental age calculation. The results showed that the mean age at early developmental stages (A-D) was lower in males than in females in all wisdom teeth .On the other hand, the stages from E-G there was earlier development in females in maxillary molars but it was earlier in males in mandibular molars. The full eruption of third molar (H stage) was earlier in females in the four molars. The greatest correlation coefficient was found between the developmental stages of maxillary molars in females. A strong correlation was found between lower right and lower left molar in females, a similar correlation was found between upper left and lower left third molars in females. The lower correlation coefficient was noticed between antimeres such as upper right and lower right in males. The probability of an individual being older than 18 years in case of fully developed wisdom was 100% in females when one molar or more were found but it was 66.7% in males when one molar is present and 100% when two or more molars were present. Regression analysis was performed in order to obtain regression formulae for dental age prediction.

Radiographic evaluation of third molar development in relation to chronological age among Turkish children and youth

A sharp increase in forensic age estimation of living persons has been observed in recent years. However, ethnic populations residing in different countries have been insufficiently analyzed. According to 2004 data compiled by the Essen-based Turkey Research Center, there are 3.8 million Turkish people living abroad, and 3.2 million of them reside in European Union countries. Despite the high number of Turks living abroad, little is known about third-molar development for forensic application in this population. Hence, it was considered worthwhile to determine the developmental stages of the third molar in a group of Turkish population, to assess chronological age estimation based on the developmental stages, and to compare third molar development according to sex, age and location. Orthopantomograms of 1134 Turkish patients, ages 4–20 years were examined and third-molar developmental stages were evaluated based on Demirjian's classifications. Orthopantomograms were scored by two different observers, and Wilcoxon matched-pairs signed-ranks test used to test intra- and inter-observer reliability revealed a strong agreement between both intra- and inter-observer measurements. Linear regression analysis was performed to correlate third-molar development and chronological age, and further statistical analysis was performed to determine the relation between sex, age and location. Results showed a strong linear correlation between age and molar development (males: r 2 = 0.57; females: r 2 = 0.56). Mineralizations of left and right third molars were compared using Wilcoxon tests, and no statistical differences were found. No significant differences were found in third-molar development between males and females. Mandibular third molar crypt formation was observed in 2.4% of patients at age seven and maxillary third molar crypt formation was observed in 1.3% of patients at age seven. A strong correlation was found between third-molar development and chronological age. Among the Turkish population, third molar crypt formation is observable at as early as 7 years in both the mandible and maxilla. Agenesis can be determined conclusively if no radiolucent bud is present by age 14.

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 κ statistics. The κ 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.

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 κ 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.