2012, Vol.25, No.1

Anatomy & Biological Anthropology 2023 KCI Impact Factor : 0.33

pISSN : 2671-5651 / eISSN : 2671-566X
https://journal.kci.go.kr/aba

This study was undertaken to investigate the morphological changes of scalp hair according to weathering after burial and to offer basic data for forensic science. To examine the effect of weathering degree, the 51 human scalp hairs buried after death were taken from deceased individuals in tombs in Korea. The morphological changes in weathering hair shafts of the scalp were investigated using the transmission electron microscopes (TEM). There were little morphological differences of weathering depending on the burial period. The weathering changes includes detachment of cuticle layer, aggregation of macrofibril and hollow formation in the cortex according to the burial period. These results could provide basic data to the field of forensic medicine.

The aim of this study was to propose new more reliable peripheral nerve transection model to overcome the defect of the traditional sciatic axotomy model by specifically transecting L5 spinal nerve just after emerging from the intervertebral foramen and confining analysis area to the L5 spinal segment. The adult male Sprague-Dawley rats, weighing 300~350 g at the time of surgery, were used for the experiments. Four different experimental groups were used. 1. Sciatic nerve transection (Sc-Tx) group: transect the sciatic nerve in the popliteal fossa where it divided into the common peroneal nerve and tibial nerve. 2. L5spinal nerve transection (L5-Tx) group: L5 spinal nerve was specifically transected. 3. Suture (Su) group: L5spinal nerve was transected and immediately sutured. 4. Control group: the same surgical procedure with L5spinal nerve transection group was performed except for the excision of L5 spinal nerve. To distinguish L5motoneurons from the other level ones, the animals were received the retrograde tracer, FluoroGold into the axotomized proximal nerve stump. Serial coronal frozen sections at 40 μm thick through the L4 to L6 spinal segment was performed and the resultant total number of sections was about 180. Approximate serial 50 sections (approximately 2 mm) could be considered as the L5 segment based on the number of the fluorescent signals (above 20). L5 spinal segment could be differentiated from L4 and L6 segment based on their morphological characteristics under Cresyl violet stain. In L5-Tx group, at 2 and 4 weeks post-transection, the number of L5 spinal motoneurons was reduced by 8%. Meanwhile, Sc-Tx and Su groups showed no statistically notable changes. In this study, the authors could propose more reliable peripheral nerve axotomy model than the conventional sciatic nerve axotomy model by specifically transecting L5 spinal nerve and confining the investigating area within the L5 spinal segment.

The main aim of dental implant placement on the anterior region is to recover the function and esthetics. Therefore, this study examined the angulation between the long axis of the anterior teeth and the alveolar process, and thickness of the alveolar bone on the anterior region. Twenty-five cadaver heads (18 maxillae and 23 mandibles) were examined (16 male and 9 female, mean: 56.7years). The angulation between the long axis of the anterior teeth and the alveolar process was measured, and the alveolar bone thickness was measured in the three levels (crest; C, middle; M, apex; A) on the labial and lingual sides. All data was analyzed statistically using one-way ANOVA. The maxillary anterior teeth showed two to three times more lingual inclination than the mandibular teeth. The difference in maxillary alveolar bone thickness on the labial and lingual sides was significant in all levels,particularly in the apex. The mandibular alveolar bone thickness on the labial and lingual side was significantly different only in the apex. In conclusion, the alveolar bone thickness on the anterior region was too thin, and the long axis of the maxillary anterior teeth showed more lingual inclination than the alveolar process. Therefore, clinicians need to be a detailed assessment of the labial alveolar bone for dental implant placement.