The vestibular and geniculate ganglia of the ear in experimental animals carry both of the tyrosine hydroxylase (TH)-positive sympathetic neurons and the neuronal nitric oxide synthase (nNOS)-positive parasympathetic neurons. With an aid of immunohistochemistry, we examined these ganglia as well as the horizontal part of the facial nerve using specimens from 10 formalin-fixed elderly cadavers. The submandibular ganglion from the same cadavers was used for the positive control for both markers. Although there was a nonspecific reaction in nuclei for the present antibody of nNOS, these ganglia were unlikely to contain either nNOS- or TH-positive neurons. However, we did not deny a possibility that the absence was a result of degeneration with aging. In contrast, the facial nerve horizontal part consistently contained both of TH-positive- and nNOS-positive fibers. These fibers might regulate blood supply to the facial nerve and the dysregulation leads to edema to elevate pressure on the nerve within its osseous canal.
The posterior superior alveolar canal (PSAC) composed of several canals which contains vessels and nerve in molar region of the maxilla of Japanese macaque. The PSAC of maxilla run to the maxillary sinus. However, the PSAC and accessory canal (AC) of the maxilla in the Japanese macaque (JM) is unknown in morphological features in the maxilla. The purpose of this study was to describe the PSAC of the primates and to determine whether this structure could be used as a model for the human clinical condition. In this study, we showed the course of PSAC structure of the 23 JMs (male: n = 15; female: n = 8) using a cone-beam computed tomography apparatus. In the results, we classified a type to have one AC toward, a type to have two ACs toward, and three ACs in a type to have in PSAC. The main canal have some bony branch canals (BBCs) composed of 3 types (no BBC, one BBC, two BBCs). These canals and they run downward and supply to MS, these roots of maxillary molar region of the craniofacial skeleton in contrast to numerous small accessory canals with no nerve and vessels observed in the posterior regions in maxilla. These morphology features may give useful information about MS in dental treatment human model.
In comparative anatomy, the musculocutaneous nerve is hypothesized to pass between the superficial and deep muscle bellies of the coracobrachialis muscle. The superficial belly is supplied by nerve branches of the lateral cord of the brachial plexus, while the deep belly by the musculocutaneous nerve. Observations of longitudinal sections of ten human embryonic arms (7 weeks; crown-rump length 26-32 mm) demonstrated that the coracobrachialis muscle was always continuous with the short head of the biceps muscle. If the aforementioned hypothesis was applied, the deep belly behind the musculocutaneous nerve course was continuous with the biceps. However, such a close relation between the coracobrachialis and biceps was not known in supplying nerves in adults. A further study using embryos of some apes without the deep belly of the coracobrachialis would be necessary for the comparison between a pattern of the embryonic muscle division and the muscle classification in comparative anatomy.
In this paper, using full-body CT images of elderly and advanced elderly Japanese cadavers, we measure maxillary and other paranasal sinus volumes in order to examine the effects of age, sex, presence or absence of maxillary molars, and other factors on changes to maxillary sinus volume. The research subjects consisted of 77 of 95 cadavers donated to the Kanagawa Dental University between 2012 and 2014, which average age was 82.6 ± 10 years (33 were male, average age 79.3 ± 8.3 years, and 44 were female, average age 85.1 ± 11.7 years). Sinus volume was measured from full-body CT images on the horizontal plane and computed using the 3D volume rendering software. The average maxillary sinus volume was 31.3 ± 13.2 cm3 (average value ± one standard deviation; hereafter the same), with values of 32.9 ± 13.2 cm3 (6.7 cm3 ～ 55.7 cm3) for males and 29.6 ± 12.5 cm3 (5.5 cm3 ～ 52.9 cm3) for females. In this report, we studied the effects of aging, sex, and state of remaining molars on changes to paranasal sinus volume in the maxillary sinus. These results give additional information about maxillary sinus volume of Japanese oldest-old peoples.