The purpose of this study was to investigate the characteristic multidetector computed tomography (MDCT) findings of maxillofacial fractures resulting from falls in the elderly. A prospective study was performed in 38 patients over 64 years of age with maxillofacial fractures resulting from falls underwent 64-MDCT. Maxillofacial fractures were classified into eight types: mandibular median, paramedian, angle, condylar, Le Fort (I-III), isolated anterior maxillary, isolated zygomatic arch and zygomaticomaxillary complex. Statistical analysis of the relationship between gender and maxillofacial fracture locations was performed using χ^2 test with Fisherʼs exact test. A P value less than 0.05 was considered statistically significant. The prevalence of male and female were 40.7% and 59.3% of condylar type (p=0.288), and 80.0% and 20.0% of zygomaticomaxillary complex type (p=0.170), respectively. In conclusion, regarding to elderly patients, the condylar type was considered more frequency in female with maxillofacial fractures resulting from falls, and the zygomaticomaxillary complex type was considered more frequency in male with those.

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Dysfunction of salivary glands and decrease in saliva are serious problems in clinical dentistry since saliva maintains oral health. Tissue injuries caused by γ-irradiation or autoimmune syndromes induce atrophy of salivary acinar cells. We have previously reported that cell isolation processes from rat parotid glands by digestion with enzymes mimic tissue injuries and result in decrease of expression of amylase, which indicates dysfunction of acinar cells. In this study, we found that a non-selective PKC inhibitor,　Ro31-8220, and an inhibitor of MEK1/2, U0126, suppressed the decrease of amylase activity caused by cell isolation. Gö6983, an inhibitor for novel PKC, also suppressed its decrease although Gö6976, a specific inhibitor for conventional PKC, did not. Time-dependent increase in phosphorylation of novel PKCs during culture was detected. Their phosphorylation was inhibited by addition of Ro31-8220 or Gö6983, but not by Gö6976. Phosphorylation of novel PKC was inhibited by U0126 while Erk1/2 activation was not suppressed by Ro31-8220, which suggests that activation of Erk1/2 is upstream of phosphorylation of novel PKCs. Addition of diphenyleneiodonium suppressed the activation of Erk1/2. Therefore, tissue injury during cell isolation generates reactive oxygen species,　which causes dysfunction of parotid acinar cells via activation of Erk1/2 and novel PKCs.

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To fabricate optimum prostheses, the quality of working model, especially the surface is critical. When impression is taken by laminate alginate impression, the surface property of the model is crucial since itʼs amount of water increases than that of standard W/P ratios. This study examined the model surface quantitatively and qualitatively to identify their optimum thickness of the secondary laminated impression. The thickness of the secondary impression was set to 0.4mm (A0.4), 0.6mm (A0.6), and 0.8mm (A0.8). The surface roughness of A0.4, A0.6, and A0.8 andcontrol was quantitatively assessed by scanning laser microscope, measuring Ra, Ry, Rz, analyzed with ANOVA and Dunnettʼs multiple comparison post hoc test. Qualitative observation of the surface was done by scanning electron microscope (SEM), and crystal structure was assessed by X-ray diffraction. A0.4 significantly showed roughness surface compared to control in Ra andRz (p<0.01). Also Ry was significantly high with A0.4 and A0.6 compared to the control (p<0.05). From SEM observation, the size of crystal column was prominent with A0.4 among the samples, which exhibited a different image from the control. TheX-ray diffraction detect dental stone hardened body, gypsum (CaSO₄·2H₂O), and unhardened, anhydrite (γ-CaSO₄). A0.4 detected strong peak of anhydrite that indicate unhardened characteristic of dental stone. From above optimum thickness of the secondary laminated impression was suggested at 0.8mm to keep comparable surface quality and surface texture of the single impression.

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In this study, a principal component analysis of event-related potential (ERP) waveforms was performed and patterns of waveform component extraction were examined for close investigation of the information-processing modes generated in tooth, script, and hand differentiation. Subjects were 17 fifth-year dentistry students undergoing bedside training. The task was to differentiate a tooth, script, or hand in each of a series of line drawings presented at random using the oddball paradigm with a target-to-non-target ratio of 2:8, by pressing a button only on observation of the target stimulus. ERP waveforms were analyzed by obtaining the average and grand-average Pz waveforms and subjecting them to principal component analysis. A clear difference was found between the ERP waveform component of the script differentiation and those of the tooth and hand differentiations, with a large proportion of the information-processing components representing the pattern-matching and attention-orienting modes in script differentiation, rather than the cognitive-judgment processing andaction-execution modes in tooth andhanddifferentiations. A salient difference was also found between the information-processing modes of tooth and hand differentiations, as evidenced by the independent extraction of P3a in the former, but not in the latter. The observation of differing patterns of ERP waveform component emergence thus enabled extraction of differences among the information processing modes of tooth, script, and hand differentiation.

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Mucormycosis is a rapidly progressive disease with an acute course, and represents a classic nosocomial condition. The prognosis is usually poor, with high mortality rates that are influenced by the timeliness of diagnosis and, above all, by the underlying status of the patient. This fungal infection commonly occurs in diabetics, immunocompromised hosts, patients with leukemia, lymphoma, multiple myeloma, septicemia, hepatitis, cirrhosis, or renal failure, as well as patients receiving chemotherapy or steroids. Intravenous drug abusers are also at risk. Early detection and treatment are key elements for patient survival. This article describes a case of mucormycosis affecting the palate in an elderly patient with uncontrolled diabetes mellitus.

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