Age Estimation using Cephalometrics-A Cross-Sectional Study among Teenagers of Salem District, Tamil Nadu.

Background: Age estimation is important not only in identifying dead body of a person but also in living persons since there is an increasing rate of juvenile delinquencies recorded every year. To avoid foul play by age fabrication, legal age estimation becomes important. Facial growth alteration takes place in the jawbones as age advances which can be observed with lateral cephalometry. Thus, the aim of the study is to create a regression formula for age estimation using cephalometrics of teenagers in Salem population. Materials and Methods: A cross-sectional study was done using 770 lateral cephalometrics of teenagers (13-19 yrs) in Salem population. Nine cephalometric points with two linear hard tissue measurements (condylion to mandibular plane (AFH) and palatal plane to menton (PFH)) and one angular soft tissue measurement (z angle) were recorded as predictor variables using a digital lateral cephalometric software (Carestream CS8100 SC) which were subjected to regression analysis using SPSS version 21.0 to develop a formula for age estimation. Results: Significant association on age was obtained for the two linear measurements. The regression formula generated for estimating the age was Age = 7.146 + 0.044 (AFH) + 0.146 (PFH) with R2 value = 0.674. Conclusion: Within the limitations of the present study, age estimation of teenagers in Salem population can be estimated. The predictability of the age can be increased by taking more cephalometric variables in generating the formula with increase in sample size.

Bacterial Diversity Patterns Differ in Soils Developing in Sub-tropical and Cool-Temperate Ecosystems.

Microbial diversity patterns have been surveyed in many different soils and ecosystems, but we are unaware of studies comparing similar soils developing from similar parent materials in contrasting climates. In 2008, developmental chronosequences with ages ranging from 105 to 500,000 years across Georgia (GA) and Michigan (MI) were studied to investigate how bacterial community composition and diversity change as a result of local environmental gradients that develop during pedogenesis. Geographic factors were studied between and within locations spanning two scales: (1) regionally between 0.1 and 50 and (2) ∼1700 km apart. The diversity was surveyed using high-throughput pyrosequencing, and variance partitioning was used to describe the effects of spatial, environmental, and spatio-environmental factors on bacterial community composition. At the local scale, variation in bacterial communities was most closely related to environmental factors (rM = 0.59, p = 0.0001). There were differences in bacterial communities between the two locations, indicating spatial biogeography. Estimates of bacterial diversity were much greater in MI (numbers of OTU, ACE, and Chao1) and remained 2-3× greater in MI than GA after removing the effect of soil properties. The large differences in diversity between geographically separated bacterial communities in different climates need further investigation. It is not known if the rare members of the community, which contributed to greater bacterial diversity in GA relative to MI, play an important role in ecosystem function but has been hypothesized to play a role in ecosystem resiliency, resistance, and stability. Further research on the link between bacterial diversity and spatial variability related to climate needs further investigation.

Knowledge, attitude, and perception of mothers towards emergency management of dental trauma in Salem district, Tamil Nadu: a questionnaire study.

BACKGROUND: Dental trauma is one of the main oral health problems in childhood, and can cause pain and distress. It is important to provide emergency care to combat the aftermaths of trauma. AIM: The aim of the study is to assess the knowledge and attitude of mothers regarding dental trauma and its management. MATERIALS AND METHODS: A questionnaire consisting of 33 closed-ended questions were used to interview 150 mothers who participated in the study. The questions assessed the knowledge and attitude of mothers towards their child's dental visit, dental trauma, and its management. Statistical analysis was performed using Statistical Package for Social Sciences (SPSS) version 17.0. RESULTS: Mother's previous experience of dental trauma when associated with the preservation of avulsed tooth of the child, those mothers who had the experience of dental trauma reported that they would discard the tooth which was found to be statistically significant (P < 0.05) when compared to the mothers with no experience of trauma. The education status of the study population when associated with the knowledge variables of avulsion, it was found that most of the variables had statistically significant association with P < 0.05. CONCLUSION: This study reveals that there is a lack of awareness among the mothers regarding the emergency management of dental trauma. This warrants the need of an effective communication between dental professionals and mothers for better handling of dental emergencies.

Palatal rugae in population differentiation between South and North Indians: A discriminant function analysis.

AIM: The present study is aimed at delineation of different types of rugae in two different populations and developing a discriminant function for the same. MATERIALS AND METHODS: A total of 940 subjects were included in the present study. The sample consisted of 466 subjects from South Indian population and 474 from North Indian population in the age group of 18-23 years. Neo colloid Easy flow((™)) alginate impressions of maxillary arch were made and casts were immediately poured with Type IV dental stone. A sharp graphite pencil was used to delineate the rugae and patterns were recorded according to the classification given by Kapali et al. The association between different population and different sexes was analyzed with chi-square test and a stepwise discriminant function analysis was also performed to develop a discriminant formula. RESULTS: Wavy, curved and straight rugae were the most common forms in both groups. Chi-square analysis for association between rugae shape and population groups showed significant differences among all the rugae patterns at the P < 5%. Chi-square analysis for assessing sex differences in the rugae shapes showed significant difference in straight, unification and circular type. Five rugae shapes - curved, wavy, nonspecific, unification and circular - were selected for discriminant function. CONCLUSION: The discriminant function equation obtained from the different rugae shapes in the present study was highly accurate enough to distinguish the Southern and Northern Indian population with the classification accuracy of 87.8%. Thus to identify a specific population, separate discriminant function formulae have to be developed. Hence, the study of palatal rugae is one of the simple and reliable tools for population identification in forensic science.