Assessment of sexual dimorphism using digital orthopantomographs in South Indians.

INTRODUCTION: The identification of human skeletal remains plays a crucial role in forensic investigation and its accuracy depends on the available parts of the skeleton. The mandible is the hardest and strongest bone of the skull, which exhibits a high degree of sexual dimorphism and helps to identify the sex in human remains. The aim of this study was to develop discriminant function to determine sex from the mandibular radiographs in a South Indian (Visakhapatnam) population. MATERIALS AND METHODS: This retrospective study consisted of 384 (192 males and 192 females) digital orthopantomographs (OPGs) divided into five groups according to age. Ten mandibular variables were measured using Planmeca Romexis software. The data were tabulated and subjected to discriminant function analyses using Statistical Package for the Social Sciences (SPSS) software (version 20.0) package. RESULTS: All the parameters showed a significant sexual dimorphism (P < 0.001) except for the gonial angle. An overall accuracy of 75.8% was achieved and coronoid height (CrH) was the single best parameter providing an accuracy of 74.1%. CONCLUSION: All the mandibular variables except for the gonial angle (GA) were found to be reliable in determining the sex in South Indians for forensic purposes.

Accuracy of four dental age estimation methods in southern Indian children.

INTRODUCTION: For various forensic investigations of both living and dead individuals, the knowledge of the actual age or date of birth of the subject is of utmost importance. In recent years, age estimation has gained importance for a variety of reasons, including identifying criminal and legal responsibility, and for many other social events such as birth certificate, marriage, beginning a job, joining the army and retirement. Developing teeth are used to assess maturity and estimate age in number of disciplines; however the accuracy of different methods has not been assessed systematically. The aim of this study was to determine the accuracy of four dental age estimation methods. MATERIALS AND METHODS: Digital Orthopantomographs (OPGS) of South Indian children between the ages of 6 and 16 y who visited the department of Department of Oral medicine and Radiology of GITAM Dental College, Visakhapatnam, Andhra Pradesh, India with similar ethnic origin were assessed. Dental age was calculated using Demirjian, Willems, Nolla, and adopted Haavikko methods and the difference between estimated dental age and chronological age were compared with paired t-test and Wilcoxon signed rank test. RESULTS: An overestimation of the dental age was observed by using Demirjian and Nolla methods (0.1±1.63, 0.47±0.83 years in total sample respectively) and an underestimation of dental age was observed by using Willems and Haavikko methods (-0.4±1.53, -2.9±1.41 years respectively in total sample). CONCLUSION: Nolla's method was more accurate in estimating dental age compared to other methods. Moreover, all the four methods were found to be reliable in estimating age of individuals of unknown chronological age in South Indian children.

Accuracy of Demirjian's 8 teeth method for age prediction in South Indian children: A comparative study.

INTRODUCTION: Demirjian's method of tooth development is most commonly used to assess age in individuals with emerging teeth. However, its application on numerous populations has resulted in wide variations in age estimates and consequent suggestions for the method's adaptation to the local sample. Original Demirjian's method utilized seven mandibular teeth, to which recently third molar is added so that the method can be applied on a wider age group. Furthermore, the revised method developed regression formulas for assessing age. In Indians, as these formulas resulted in underestimation, India-specific regression formulas were developed recently. The purpose of this cross-sectional study was to evaluate the accuracy and applicability of original regression formulas (Chaillet and Demirjian 2004) and India-specific regression formulas (Acharya 2010) using Demirjian's 8 teeth method in South Indian children of age groups 9-20 years. METHODS: The present study consisted of 660 randomly selected subjects (330 males and 330 females) were in the aged ranging from 9 to 20 years divided into 11 groups according to their age. Demirjian's 8 teeth method was used for staging of teeth. RESULTS: Demirjian's method underestimated the dental age (DA) by 1.66 years for boys and 1.55 years for girls and 1.61 years in total. Acharya's method over estimated DA by 0.21 years for boys and 0.85 years for girls and 0.53 years in total. The absolute accuracy was better for Acharya's method compared with Demirjian method. CONCLUSION: This study concluded that both the Demirjian and Indian regression formulas were reliable in assessing age making Demirjian's 8 teeth method applicable for South Indians.

Dental age estimation using Willems method: A digital orthopantomographic study.

UNLABELLED: In recent years, age estimation has become increasingly important in living people for a variety of reasons, including identifying criminal and legal responsibility, and for many other social events such as a birth certificate, marriage, beginning a job, joining the army, and retirement. OBJECTIVES: The aim of this study was to assess the developmental stages of left seven mandibular teeth for estimation of dental age (DA) in different age groups and to evaluate the possible correlation between DA and chronological age (CA) in South Indian population using Willems method. MATERIALS AND METHODS: Digital Orthopantomogram of 332 subjects (166 males, 166 females) who fit the study and the criteria were obtained. Assessment of mandibular teeth (from central incisor to the second molar on left quadrant) development was undertaken and DA was assessed using Willems method. RESULTS AND DISCUSSION: The present study showed a significant correlation between DA and CA in both males (r = 0.71 and females (r = 0.88). The overall mean difference between the estimated DA and CA for males was 0.69 ± 2.14 years (P < 0.001) while for females, it was 0.08 ± 1.34 years (P > 0.05). Willems method underestimated the mean age of males by 0.69 years and females by 0.08 years and showed that females mature earlier than males in selected population. The mean difference between DA and CA according to Willems method was 0.39 years and is statistically significant (P < 0.05). CONCLUSION: This study showed significant relation between DA and CA. Thus, digital radiographic assessment of mandibular teeth development can be used to generate mean DA using Willems method and also the estimated age range for an individual of unknown CA.

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.