Turner's Syndrome is a representative sex chromosome abnormality in women (designated as 45,X females). These women have a fundamental karyotype of 44 autosomes and a single X chromosome. The purpose of this study was to perform a morphometric analysis of the pulp chambers of the upper and lower molars in 45,X females using orthopantomograms. We examined 40 Finnish 45,X females and 24 of their sisters. The mean age of the 45,X females was 15.6 years and that of their female relatives was 15.3 years. We measured six parameters of the pulp chamber, including the root canals, and calculated six indices using these items. The results of these measurements and indices showed that thepulp height, root length, crown size, and cervical width in the molars of 45,X females were shorter than those in their sisters Conversely, the pulp width in the teeth of 45,X females was expanded in the mesiodistal direction. The upper and lower molars of 45,X females had low and wide pulp chambers.

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The ablation effect of laser treatment of dental tissues is mainly determined by : i) wavelength, ii) power fluence, and iii) pulse structure. To evaluate the effect of pulse structure, the 2.94 μm free electron laser (FEL) and the Er:YAG laser were used to irradiate human tooth enamel and dentin. A 2.94 μm FEL of 8-10 μsec excision with 2 Hz was generated by the 80 MeV LINAC-undulater system at LEBRA, Nihon University, with the macro-pulse structure of 20 μsec and with less than 1 pico-second micro-pulses at 350 pico-sec interval. Size and depth of the pits formed by laser irradiation were measured using a profilometer. Only a 3 mJ LEBRA-FEL was sufficient to form a crater in the enamel and dentin, and the depth of the pit formed by laser irradiation was dependent upon the power of laser. Even when the higher-powered FEL was applied, the craters showed no signs of scorching. Conversely, craters with scorching were evident when the Er : YAG laser was used on dentin. In conclusion, heat damage of dental hard tissues can be avoided using a micro-pulse structured laser.

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In this in vitro study, electron spin resonance (ESR) and nuclear magnetic resonance (NMR) were used to evaluate free radical generation and chemical structural changes of amino acids in the Carisolv system. In the ESR study, hydroxyl radical (•OH), carbon radical (•C) and 5,5-dimethyl-1-pyrrolidone-(2)-oxyl-(1) (DMPO-X) were detected in the Carisolv system. •OH was detected in a 0.25 % NaClO and 0.25% glutamic acid reaction mixture, •OH and •C were detected in a 0.25% lysine and 0.25% NaClO reaction mixture, and a DMPO-X like signal was detected in a 0.25% leucine and 0.25% NaClO mixture. More •OH was detected when the Carisolv system was irradiated with plasma light than normal room light. The NMR study revealed that all the amino acids were completely degraded to smaller molecules by NaClO. These results indicate that the free radicals generated by the Carisolv system via NaClO attacked the amino acids. Then the generated •OH in particular attacked the collagen in carious dentin and brought about degradation of the dentin structure. In addition, this mechanism was enhanced by plasma-light irradiation.

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In 2001, we carried out a dental anthropological survey of two Chinese minorities in Yuen Jian, in Yunnan Province. The subjects were young adults of the Hani and the Dai tribes, who historically derive from Tibetan and Southeast Asian regions, respectively, and from whom dental impression models were collected. Tooth measurements were made, using a digital caliper with the precision of 0.01 mm, on the mesiodistal and buccolingual diameters. Sexual dimorphism was weak : sex differences were present in both the Hani and the Dai in the upper and lower canines, but not in other teeth. Also, male teeth were larger than female in the mesiodistal diameters, especially of the upper and lower incisors and premolars. There were some significant differences between the Hani and the Dai : for example, the buccolingual diameters of the lower I1 and the upper incisors were larger in the Hani, in both sexes, while the Dai had larger lateral teeth in both males and females. The measurements were compared with those in other Asian peoples. A principal components analysis showed, on a size factor, that teeth in the Hani and Dai were generally smaller than in other Asian racial sub-groups, such as the Japanese and Philippinos ; but in males only they were larger than those of Philippine Negritos. The Hani, both males and females, have intermediate sized teeth compared with other Asian sub-groups. Anthropological affinities between the Hani and Dai were suggested by position on two shape factors resulting from the analysis.

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We present a case of ethmoid sinus osteoma. A 66-year-old woman was referred with an asymptomatic mass of the nose. Radiographs showed a rounded homogeneous radiodense lesion in the right ethmoid sinus, suggesting an osseous lesion. Computed tomography demonstrated a multi-lobulated high density lesion (2.0×1.5 cm in size) occupying the ethmoid sinus. The lesion was attached to the nasal septum and extended to the posterior orbit. Total excision of the mass lesion was performed under general anesthesia via the oral vestibular approach with an operating microscope. Histopathological examination revealed eburneous-type osteoma. The postoperative course was uneventful.

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We report a case of a large calculus in the parotid duct. A 61-year-old man was referred to us with a painless buccal mucosal swelling. Oral examination showed a hemispheric buccal mucosa swelling around the orifice of the parotid duct in the right cheek. The patient denied intermittent swelling and pain of the right parotid gland at mealtime. Salivary secretion was smooth from the orifice and there was no salivary fistula. An oblique radiograph of the right cheek revealed a single, well-defined, homogenous radiopaque mass. Computed tomography scanning showed a high-density mass, round with a 1-cm diameter. The calculus was removed by an oral approach under local anesthesia. The calculus was an irregular globule in shape, 1×1×1 cm in size, and yellowish white in color. Follow-up examination one year later was uneventful.

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In the current study, we used the modified ion dilution method to evaluate the influence of the circadian rhythm on the salivary volume in response to varying sour concentrations. We found that the salivary volume changed depending on when the sample was taken and on the sour concentration. Specifically, there was a definite trend for the salivary volume to be low in the morning and to increase from around lunchtime to evening. In addition, the influence of the circadian rhythm on salivary volume tended to be reduced by a strong taste stimulation (high sour concentration). These results suggest that the greater the amount of stimulation (sour stimulation), the smaller the effect of circadian rhythm on the salivary volume.

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In this study, we assessed the roles of postnatal lymphotoxin (LT)-α mediated signaling in the maintenance of the microarchitecture of the fully developed spleen. To investigate the role of postnatal LT-α-mediated signals in the organization of splenic microarchitecture, wild-type (LTα^+/+) mice were lethally irradiated and then reconstituted with LT-α deficient (LTα^-/-) bone marrow. The transfer of LTα^-/- bone marrow to those mice resulted in the disruption of splenic microarchitecture, including the segregation of T and B cell areas, and the formation of germinal centers and follicular dendritic cell clusters. In contrast, adoptive transfer of LTα^+/+ bone marrow to LTα^-/- mice restored the segregation of T and B cell areas and the formation of the germinal center and follicular dendritic cell cluster in the spleen. These results suggest that the maintenance of splenic microarchitecture is not programmed during development but is dependent on constant stimuli provided by LTα.

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In nitric oxide (NO)-generating cells, the citrulline/NO cycle is an important pathway in controlling the arginine supply because NO is generated from arginine by the activation of NO synthase. Argininosuccinate synthetase (AS ; EC 6.3.4.5) is a rate-limiting enzyme in the citrulline/NO cycle, which catalyses the condensation of citrulline and aspartate to form argininosuccinate, the immediate precursor of arginine. In this report, we examined AS activity in the parotid glands of rat, rabbit, mouse, and guinea pig. AS activity was detected in all species, and, in the rabbit parotid gland, most of the activity was observed in the cytosolic fraction. In the parotid glands of postnatal rabbits, AS activity increased prior to NOS activity. These results suggest that AS contributes to NO generation in the parotid gland.

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