Age estimation from skeletal remains is an important step in forensic biological identification. The main objective of this study is to develop an age estimation equation for the Thai population from vertebral osteophytes. Each vertebra in the cervical, thoracic and lumbar segments was scored for degree of osteophyte formation. Classification was carried out in accordance with the criteria established by Snodgrass and Watanabe, and used a new modified score of the length of vertebral osteophyte for age estimation. The sample included 400 individuals (262 males, 138 females) ranging in age from 22 to 97 years. A sample of Thai vertebral columns was used, the columns being divided into the following groups of vertebrae: cervical (C2–C7), thoracic (T1–T12), and lumbar (L1–L5). Each vertebra was scored for the degree of osteophyte formation and the accumulated data was analyzed statistically. Correlation coefficients and R-squared from mean in lumbar vertebrae for females of criteria established by the method of Snodgrass and Watanabe, the new modified score by length of vertebral osteophytes were 0.801 and 0.642 (P<0.01); 0.755 and 0.57 (P<0.01); 0.786 and 0.618 (P<0.01), respectively. This study presents all 23 subcategories (C2–L5) of the vertebrae to apply in real situations, showing all age estimation equations for males, females and combined sexes of unknown sex. One application of this study is age estimation when dealing with forensic cases in the Thai population.
Asian Continental Ancestry Group ; Classification ; Female ; Forensic Anthropology ; Forensic Sciences ; Humans ; Lumbar Vertebrae ; Male ; Methods ; Osteophyte ; Research Design ; Spine ; Thailand

Sex determination is an important step in biological identification from skeletal remains, especially in forensic circumstances. Many authors suggested that the morphological study was more subjective than the metric. There are various craniometric studies in different populations. They revealed that there was population-specific for the sex discriminant equation derived from each population. Thus, the present study aimed to evaluate sexual dimorphism and develop the discriminant function from 200 Thai skulls. Twenty-five standard cranial measurements were examined. The results revealed that males' cranium were statistically significant larger than females' in all measurements (P<0.05), except for minimum breadth of nasal bone. Sexual dimorphism index also expressed relatively high male/female ratio indicating great sexual dimorphism. The best practical equation for sex determination with six measurements (maximum cranial length, bizygomatic breadth, biauricular breadth, nasal height, biorbital breadth and right mastoid length) was derived from a stepwise discriminant method. This equation with 90.6% accuracy (91.1% in male and 90.0% in female) can provide valuable application utilizing in sex determination from skull in a Thai population.
Asian Continental Ancestry Group* ; Cephalometry ; Humans ; Male ; Mastoid ; Nasal Bone ; Skull

Stature is an essential component of biological profile analysis since it determines an individual’s physical identity. Long bone dimensions are generally used to estimate the stature of skeletal remains; however, non-long bones such as the sternum, cranium, and sacrum may be necessary for some forensic situations. This study aimed to generate a regression equation for stature estimation of the skeletal remains in the Thai population. Ten measurements of the sacrum were measured from 200 dry sacra. The results revealed that the maximum anterior breadth (MAB) provided the most accurate stature prediction model among males (correlation coefficient [r]=0.53), standard error of estimation (SEE=5.94 cm), and females (r=0.48, SEE=6.34 cm). For the multiple regression model, the best multiple regression models were stature equals 41.2+0.374 (right auricular surface height [RASH])+1.072 (anterior-posterior outer diameter of S 1 vertebra corpus [APOD])+0.256 (dorsal height [DH])+0.417 (transverse inner diameter of S 1 vertebra corpus [TranID])+0.2 (MAB) with a SEE of 6.42 cm for combined sex. For males, stature equals 63.639+0.478 (MAB)+0.299 (DH)+0.508 (APOD) with a SEE of 5.35, and stature equals 75.181+0.362 (MAB)+0.441 (RASH)+0.132 (maximum anterior height [MAH]) with a SEE of 5.88 cm for females. This study suggests that regression equations derived from the sacrum can be used to estimate the stature of the Thai population, especially when a long bone is unavailable.

The estimation of sex is an essential component of forensic osteological analyses, and the potential of an incomplete radius for sex determination of human remains is investigated. The present study was conducted on 200 left-right pairs of radial bone from a northern Thai population (100 males and 100 females). The most dimorphic single parameter was maximum head diameter (MDH) with accuracies 92.0% for the right side and 90.5% for the left side. At the distal part of radius, the distal end width of the radius (RDEW) was the best sex indicator, in which the sex classification accuracies were 91.5% and 89.0%, for the right and left sides, respectively. Stepwise discriminant function analysis was performed for all measurements and specified separately to the proximal and distal radius. The circumference of the radial neck, headtuberosity length, MDH, and RDEW were selected for the stepwise procedure as these parameters produced the best correct classification results for both sides. The use of proximal radius for sex estimation was examined, with accuracies of 95.0% and 93.0% for the right and left sides, respectively. The sex classification functions for distal radius provided the accuracies of 92.5% and 89.5%, for the right and left sides, respectively. In summary, the fragments of radius indicated a high ability to estimate sex in the Northern Thai population.

The estimation of sex is an essential component of forensic osteological analyses, and the potential of an incomplete radius for sex determination of human remains is investigated. The present study was conducted on 200 left-right pairs of radial bone from a northern Thai population (100 males and 100 females). The most dimorphic single parameter was maximum head diameter (MDH) with accuracies 92.0% for the right side and 90.5% for the left side. At the distal part of radius, the distal end width of the radius (RDEW) was the best sex indicator, in which the sex classification accuracies were 91.5% and 89.0%, for the right and left sides, respectively. Stepwise discriminant function analysis was performed for all measurements and specified separately to the proximal and distal radius. The circumference of the radial neck, headtuberosity length, MDH, and RDEW were selected for the stepwise procedure as these parameters produced the best correct classification results for both sides. The use of proximal radius for sex estimation was examined, with accuracies of 95.0% and 93.0% for the right and left sides, respectively. The sex classification functions for distal radius provided the accuracies of 92.5% and 89.5%, for the right and left sides, respectively. In summary, the fragments of radius indicated a high ability to estimate sex in the Northern Thai population.

Image analysis has an increasing role in the identification of individuals in forensic application. Beside the bones, microstructural of arteries can be used in age estimation study. Aorta is the largest elastic artery which consists of many elastic fibers. Elastin in arterial wall highly resist to chemical and physical influence. The purposes of the study were to quantify elastic fibers in tunica media in each location of the aorta and examine the correlation between elastic fibers and age by using image analysis program. A total of 36 human aortas were dissected in 4 locations. The aortas were obtained from cadavers with an age range of 20 to 90 years. Specimens were stained with Elastic Van Gieson staining. Histological images were investigated about elastic fibers using light microscope with cellSens program and aorta image analysis was used for the evaluation of data. The results showed that the mean percentage density of elastic fibers in the ascending aorta and the aortic arch increased. However, the mean percentage density of elastic fibers decreased in the 31 to 40 years age group in the thoracic aorta and the abdominal aorta and decreased in each location of aorta continuously until 81 to 90 years. The abdominal aorta showed the highest correlation with age (r=0.732) followed by the thoracic aorta, the aortic arch and the ascending aorta, respectively. Changes in the percentage density of elastic fibers in the tunica media of the aortic wall can be used to add information to age estimation for identification purposes.