Age estimation is one of the major components of forensic identification. Cranial suture closure has long been used as indicator for age estimation. Maxillary sutures have been less studied for estimation of age at death because they vary in their timing of closure with age. The purpose of this study was to estimate age by examining 190 Thai skulls with age ranging between 15-93 years from Forensic Osteology Research Center, Faculty of Medicine, and Chiang Mai University. Four parts of maxillary suture (incisive, anterior, transverse, and posterior sutures) were investigated the suture obliteration of each suture by computerizing from photograph. The suture were measured by pixel counting.The prediction model which based on the support vector machine (SVM) for regression or support vector regression (SVR) was utilized for data analysis. The results showed high correlation (R2 = 0.9086) between the predicted age and actual age. Plot between actual age group and predicted age in seven groups also revealed high correlation (R2 = 0.9434). These can be implied that we are able to use this SVR model to predict age at death using maxillary suture information.The interesting issue is to further apply this model in more cases to ensure the generalization of the finding. This study is the first attempt to estimate age at death using a new method based on novel analysis which considers a characteristic of relationship between maxillary suture closures with age that are not in linear form. The present study may contribute as a basis knowledge and method for further study of age estimation in archaeological and forensic anthropological contexts, especially when only skull or base of skull are found.
Sex estimation is one of the crucial procedures in the biological profile identification of human skeletal remains. Knowing sex of unknown case can lead to accurate and appropriate methods for predicting age, stature, ancestry, or even personal identification. Skull is one of the most reliable one among other skeletons and it is usually retained for both archaeological and forensic contexts. Although many morphological features and metric measurements of skull have been studied for sexing, but to the best of our knowledge is no study on maxillary suture length for sex estimation. Therefore, this study aims to develop a new sex estimation method for a Thai population by determining three maxillary suture lengths: anterior, transverse, and posterior maxillary suture, by computerizing amount of pixel obtained from photographs of these sutures. The present study was conducted on 190 Thai bone samples of which 96 were males and 94 were females. Independent t test revealed statistically significant difference (P<0.01) between males and females in all maxillary suture measurements. Equations derived from prediction model, which required three maxillary suture lengths gave 76.8421% accuracy from the leave-one-out cross validation in estimating sex percentage accuracies in predicting sex from these equations, which were relatively moderate. This study provides a novel and objective sex estimation method for Thais. It suggests that maxillary suture length can be applied for sex estimation. The new computerized technique will contribute basis knowledge and method for sex estimation, especially when only base of skull is available in forensic circumstance.