Conventionally, the protrusive check bite method has often been used clinically to measure inclination of the sagittal condylar path on an articulator. This method, however, involves several problems such as instability in determining the inclination. We assessed the ability of a digital six-degrees of freedom mandibular movement analyzing system to measure sagittal condylar path inclination, and compared the results with data generated using two other methods, the protrusive check bite method and the Gnatho-Hexagraph method. We found that the Gnatho-Hexagarph provided a useful means of measuring sagittal condylar path inclination in patients with a large number of missing teeth. We also found that use of the Gnatho-Hexagraph facilitated measurement of the sagittal condylar path inclination simply on the basis of the mouth-opening movement, without requiring measurements during anterior movement. This method is not affected by various problems known to be associated with the conventional protrusive check bite method.

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Osteoporosis is caused by a decrease in bone mass resulting from estrogen deficiency. We hypothesized that taking selective estrogen receptor modulator (SERM) with dietary intake of isoflavones could have a mutually potentiating effect in postmenopausal women with osteoporosis. The purpose of this study was to investigate the effect on osteoblasts of the combined use of daidzein (Dz), which is a phytoestrogen derived from soy isoflavone, and raloxifene (Ral), which acts on different antiresorptive agents. Osteoblastic KUSA-A1 cells were grown in culture medium with Dz and/or Ral. The differentiation and mineralization of osteoblasts were determined using alkaline phosphatase (ALP) activity and von Kossa staining. Production in culture supernatant of osteocalcin, receptor activator for nuclear factor κB ligand (RANKL), interleukin-6 (IL-6) and osteoprotegerin (OPG) was evaluated by enzyme-linked immuno sorbent assay (ELISA). The ALP activity was expressed significantly in the presence of Dz (10^-6M) and Ral (10^-7M) at 14 days. RANKL expression decreased significantly in the presence of Dz and Ral at 14 days. There were no significant differences in the production of IL-6 in the presence of the various conditioned media. These findings indicate that concomitant treatment of osteoporosis with daidzein and raloxifene may inhibit bone loss.

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We designed a questionnaire to study how oral surgeons and general practitioners prescribe antibiotics for infection control during oral surgery. The results suggested that the criteria for administration of antibiotics are not well understood by all dentists. This problem could be improved by making free use of communication networks to provide antimicrobial prophylaxis information. Further, the criteria for antibiotic administration should be updated in dental school curriculums.

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Salicylates such as sodium salicylate and aspirin (acetylsalicylic acid) have been widely used for various inflammatory diseases including rheumatoid arthritis and periodontitis. However, the effects of salicylates on bone metabolism remain unclear. We investigated whether salicylates affect differentiation of mouse monocytic RAW264 cells into osteoclast-like cells. Both sodium salicylate and aspirin slightly induced differentiation of RAW264 cells into tartrate-resistant acid phosphatase (TRAP)-positive osteoclasts, and enhanced osteoclast differentiation induced by a low concentration of receptor activator of nuclear factor-κB ligand (RANKL). Other nonsteroidal anti-inflammatory drugs (NSAIDs) without salicylic structure including ibuprofen, meloxicam, and celecoxib did not affect osteoclast differentiation. Since it has been reported that mitogen-activated protein kinase (MAPK) signaling plays a crucial role in RANKL-induced osteoclast differentiation, we examined the effects of salicylates on extracellular signal-regulated kinase (ERK) and p38 MAPK. Although phosphorylation of p38 was augmented by both aspirin and sodium salicylate, ERK phosphorylation was suppressed. Furthermore, osteoclast differentiation induced by RANKL and salicylates was suppressed by SB203580, a specific inhibitor of p38 MAPK. These results were consistent with the previous report which found that although RANKL-induced osteoclast differentiation was suppressed by inhibition of p38, it was enhanced by ERK inhibition. This suggests that salicylates induce osteoclast differentiation via MAPK signaling.

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We investigated the vertical relation between the skeletal and alveolar components of the Japanese face using a simple assessment of vertical proportions of the face. We analyzed 114 lateral cephalometric radiographs of subjects judged to have attractive profiles. Subjects were selected who had upper and lower lips within the soft tissue E-line. They were divided into five groups based on FMA. The principal measurement items used in this analysis were the N-Me line, the S-Go line, the distance of Me perpendicular to the palatal plane, the distance from Ar to Go, and the FMA. We used the ratio of S-Go to N-Me to assess the skeletal component and the ratio of Ar-Go to the distance of Me perpendicular to the palatal plane to assess the alveolar component. We also investigated how FMA correlates with these two components.
We found that the ratio of the distance of Ar-Go to the distance of Me perpendicular to the palatal plane was correlated with FMA and with the ratio of S-Go to N-Me in all groups. The most acceptable ratio of the alveolar component occurred for an FMA between 25 and 32 degrees.
For an FMA between 25 and 32 degrees, 72% was the best ratio of for the alveolar component in order to present was best good balance in the profile. These findings suggest that we can use both FMA and the ratio of the distance of Ar-Go to the distance of Me perpendicular to palatal plane when determining individualized treatment targets.

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Natural killer (NK) cells play a key role in inflammation and tumor regression through their ability to migrate into tissues. The two major subsets in NK cells are CD56^bright CD16^dim/- and CD56^dim CD16⁺. The cytotoxic activity of CD56^dim NK cells is significantly greater than that of CD56^bright cells. Regarding cytokine production, the situation is inverted. CD56^bright NK cells are the most efficient cytokine producers. The role of CD56^bright CD16^- cells is not clear. CXCL12 is a chemokine that promotes Iymphocyte invasion and migration into tissues; however, the mechanism for this process remains incompletely understood. This study demonstrated that the NK92 cell population, which is the human NK cell line, was CD56^bright CD16^-. We examined the production of pro-matrix metalloproteinase (MMP) 1 induced by CXCL12 stimulation on NK92 cells. Pro-MMP 1 production was significantly enhanced by CXCL12 stimulation. In addition, the production of pro-MMP 1 was markedly inhibited by SB203580 (p38 inhibitor). These results suggest that p38, which is the family of mitogen activated protein kinases (MAPKs), was involved in the production of pro-MMP 1 from CXCL12-stimulated CD56^bright CD16^- NK92 cells.

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We studied longitudinal changes in the mandibular alveolar ridges of edentulous patients by comparing the relative position of the mental foramen over time in panoramic radiographs of patients visiting Osaka Dental University Hospital. We examined the panoramic radiographs of 73 patients (25 males and 48 females) with edentulous mandibles, who had full dentures fabricated two or more times from 1976 to 2003. The average age at initial examination was 66 years. During the investigation period, the mandiblar full dentures were fabricated twice for 68 subjects and 3 times for 5 subjects. The interval between fabrications ranged from 1 to 17 years with an average of 5.4 years.
Regression analysis showed that the mandible of the edentulous patients resorbed over time. We found that the length of time wearing the denture had a greater influence on resorption of the alveolar ridge than age, gender or side (left or right). Although wearing a full denture promoted resorption of the mandible, the resorption was less in patients who had been using the full denture for a long time.

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Periodontal disease is an inflammatory condition caused by periodontal bacteria. Its development and progression are related not only to bacterial pathogenicity, but also to the host response in the inflamed periodontal tissue. Recent studies have clarified the relationship between periodontal and systemic diseases. In this study, we measured the plasma levels of the proinflammatory cytokines interferon gamma (IFN-γ) and monocyte chemoattractant protein-1 (MCP-1), and the anti-inflammatory cytokine interleukin-10 (IL-10) in rats with spontaneous periodontal disease (ODUS/Odu), an animal model of periodontal disease developed and maintained in our laboratory. These rats are prone to marked plaque formation on the mandibular incisors, and develop gingivitis and periodontal pockets.
Plasma cytokine levels were measured in ODUS/Odu and control rats (Res) at 0 (5 weeks of birth), 1, 3, 6, 9, and 12 months after the start of the experiment using an enzyme-linked immunosorbent assay (ELISA) kit. The plasma levels of the proinflammatory cytokines IFN-γ and MCP-1 were significantly greater in ODUS/Odu than in Res throughout the experimental period (p<0.001). However, the plasma level of the anti-inflammatory cytokine IL-10 was significantly lower in ODUS/Odu than in Res throughout the experimental period (p<0.001). These results, similar to those obtained in patients with periodontal disease, suggest that the ODUS/Odu are a useful animal model of human periodontal disease.

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The Long-Term Care Insurance Law of 2000 authorizes dental services in health care facilities for the elderly. We investigated the use of drugs by residents in health care facilities for the elderly and compared it with the use by outpatients at our dental clinic for the elderly. The subjects were 98 residents (21 males and 77 females) with a mean age of 86 years who were in health care facilities for the elderly in May 2005, and 178 patients (67 males and 111 females) with a mean age of 77 years who visited the Dental Clinic for the Elderly at Osaka Dental University Hospital between May and July 2005. Based on records at each facility we investigated the underlying diseases, drugs in use, degree of independence of each patient, and the level of care each needed. At our dental clinic for the elderly, the underlying diseases and drugs in use were surveyed by a medical interview and by reviewing package inserts accompanying the drugs.
The number of underlying diseases was greater in the health care facilities for the elderly than in our dental clinic for the elderly for all age groups. Cardiovascular diseases accounted for the greatest percentage, and neurological diseases were more common in the health care facilities than in our dental clinic. The mean number of drugs in use was similar among the age groups: about 3.3 in the Dental Clinic for the Elderly and 4.1 in the health care facilities. The percentages of gastrointestinal drugs and neurological drugs were greater in the health facilities than at our clinic. Fifty percent of the cardiovascular medications were for hypertension, and more than half of the hypotensive medications were calcium antagonists.

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