Inflammation-mediated bone loss is a major feature of various bone diseases, including chronic periodontitis, rheumatoid arthritis, and osteoarthritis, and is due to an imbalance in bone remodeling that favors resorption. This imbalance is caused by increased cytokine levels in the inflamed tissue. Interleukin (IL)-17 is secreted primarily by activated Th17 cells, and IL-17s and IL-17 receptors play an important role in many autoimmune and inflammatory diseases. The aim of this paper is to review the differences between the indirect effect of IL-17A via osteoblasts and the direct effect of IL-17A on differentiation of osteoclast precursors into osteoclasts and the function of mature osteoclasts in the presence of receptor activator of nuclear factor êâ ligand (RANKL). IL-17A stimulates the production of bone resorption-related inflammatory cytokines through an autocrine mechanism involving celecoxib-blocked prostaglandins (PGs), mainly PGE₂, in osteoblasts. Furthermore, IL-17A induces the differentiation of osteoclast precursors into osteoclasts and the function of mature osteoclasts via PGE₂ in osteoblasts. On direct effect of IL-17 to osteoclast precursors in the absence of RANKL, IL-17 induces the differentiation as well as indirect effect via osteoblasts. However, the differentiation and function of osteoclasts are suppressed by stimulating osteoclast precursors directly with IL-17A in the presence of RANKL. In conclusion, the effect of IL-17A on RANKL-induced osteoclastogenesis may conflict with the direct action on osteoclast precursors and the indirect action through osteoblasts.

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To elucidate the effect of local bFGF administration, we administered a total of 0.3μg rhbFGF was to the left mandibular condyle by three injections of 0.1μl bFGF solution for 3 days after birth. The contralateral condyles with three injections of 0.1μl physiologic saline served as controls. Serial sections including the widest condyle were evaluated with H-E staining and immunostaining for PCNA. The maximum width of condyle, proliferative zone thickness, proliferative zone thickness ratio and proliferating index were analyzed using image analysis software after digital image capture of H-E stained sections. All condyles were composed of fibrous, proliferative, maturation and hypertrophic cell zones without significant abnormal findings. Experimental condyles demonstrated a markedly thickened proliferative zone compared with that of the controls at 1 day after the injection. At 4 and 7 days, chondrocytes and hypertrophic chondrocytes of the experiments increased in thickness. However, at 14 days after the injection, both the controls and experiments showed similar features with an upward shift of ossification front and active formation of bone trabeculae. Morphometrically, all values of experiments were significantly higher than those of the controls. Especially at 4 days after the final injection, proliferative zone thickness and proliferative index values of the experiment reached a peak and were nearly 1.6-fold higher than those of the control, which were statistically significant compared to other experimental groups. Despite the short half-life of rhbFGF, its effect seems to be prolonged by synergic actions of growth factors such as bFGF or TGF beta1. In conclusion, we showed that local administration of bFGF was feasible for accelerating mesenchymal cell proliferation of mandibular condyles of newborn mice in the lactation period after birth.

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The effects of postmenopausal osteoporosis for bone defect healing processes have already been reported, but not for senile osteoporosis caused by low-turnover metabolism. Low-Intensity-Pulsed Ultrasound (LIPUS) is known to promote bone defect healing in high-turnover osteoporosis an animal model. The aim of this study was to investigate the effect of LIPUS on the bone-healing process in a low-turnover osteoporosis model using the Senescence-Accelerated Mouse Prone 6 (SAMP6) strain of mice. Twenty-week-old SAMP6 and Senescence-Accelerated Mouse Resistant (SAMR1) mice were used as senile osteoporosis and normal aging models, respectively. Bone defects (diameter, 0.9 mm) were created in the both SAMP6 and SAMR1 femurs. At 7days after surgery, the LIPUS irradiation groups of SAMR1 (R1LG) and SAMP6 (P6LG) were exposed to LIPUS (1.0 MHz, 320 mW, 15 min/day) for 6 days. The non-irradiation groups of SAMR1 (R1CG) and SAMP6 (P6CG) were used as controls. All groups were sacrificed at 14 days after creation of bone defects. Radiological analysis, histological evaluation and immunohistochemical staining for osteocalcin (OC) were performed. From the radiological evaluation, the new bone of defected area in SAMR1 group showed cortical bone-like structure, but that in the SAMP6 group showed trabecular bone-like structures. The increase in bone area in P6LG was greater than that in P6CG according to chronological change analysis using X-ray micro-CT (p < 0.01). Histological analysis revealed outward new bone formation originating in the periosteum in P6LG. Positive reaction for OC was localized on the surface of new bone in P6CG, whereas that in P6LG was observed over the whole region of new bone, from the outer to the bone marrow side.
These results showed that LIPUS accelerates healing on low-turnover osteoporosis by promoting bone formation from periosteum and supplementing reduced bone formation from bone marrow.

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To improve the osteogenic and anti-bacterial activity for the hydroxyapatite coated titanium substrate Zn containing HA biological coating was prepared on commercially pure Ti via the sol-gel method after treatment by oxidation which produced a porous titania coating on the titanium. The phase structures of the coatings were characterized by X-ray diffraction. The release concentration of zinc was measured by an inductively coupled plasma spectrometer. In vitro co-culture assays were performed to evaluate the cell morphology and attachment of MG-63 cells to the coated titanium. The anti-bacterial effect of the ZnHA/TiO₂ coating was evaluated on Porphyromonas gingivalis w83. The cell micro morphology on the ZnHA/TiO₂ coatings was more polygonal than that of HA/TiO₂ coatings when viewed by SEM. It was confirmed by fluorescence microscopy observations that the MG-63 cells on the hybrid coating layer were favorably adhered. Compared with the HA/TiO₂ coating, the ZnHA/TiO₂ coating significantly inhibited the growth of Porphyromonas gingivalis. The results suggest that the ZnHA/TiO₂ hybrid coatings on titanium implants should possess better mechanical binding properties and biocompatibility.

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Preventing xerostomia (dry mouth) can be a major challenge for some patients. The aims of this study were to evaluate the rheological properties of seven commercially available oral moisturizers in terms of their G’ and tan δ values and to investigate the relationship between the G’ values and sensory evaluations of the smoothness, spreadability, moistness, and substantivity. All of the samples had lower G’ values and higher tan δ values when the shear strain was increased. A negative correlation was observed between the G’ value and the smoothness and spreadability. These correlations will help us to understand the characteristics of various oral moisturizers.

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Research into halitosis (commonly referred to as “bad breath”) has been increased recent years. Public awareness of halitosis has also increased, as a result of improved attention to hygiene, and the number of dental patients being treated for halitosis is increasing globally. Halitosis is known to be caused by volatile sulfur compounds (VSCs), formed by decomposition of sulfur-containing amino acids, and these can lead to infection of periodontal tissue. Previous studies have shown that zinc chloride and citric acid effectively suppress VSC release. In this study, we compared the VSC-inhibiting effects of zinc chloride alone, and of a zinc chloride/citric acid combination, in artificial saliva and in distilled water, each containing hydrogen sulfide. Our results showed that the inhibition of VSC release from distilled water achieved using citric acid/zinc chloride (18%) was less than that obtained using zinc chloride alone (27%). However, 100% inhibition was achieved in artificial saliva using the combined solutions, compared with 18% using zinc chloride alone. We believe that at the pH of the artificial saliva, some hydrogen sulfide is present as bisulfide ions, which readily react with zinc ions. Also, zinc ions form a chelate with citric acid, preventing formation of insoluble, unreactive zinc hydroxide. Our results suggest that a zinc chloride/citric acid combination would be an effective treatment for halitosis.

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As a non-degradable material showing excellent biological compatibility and mechanical properties, the titanium fiber web (TW) scaffold has been applied in bone regeneration. It is generally accepted that hydroxyapatite (HA) coating accelerates osteoblast maturation and functional activity on the titanium surface. Recently, a thin HA coating using the molecular precursor method was developed, and sufficient apatite coating was achieved inside TW. The aim of the present study was to evaluate the bone-forming capacity using HA-coated TW (HA-TW) in external augmentation. Sintered titanium fiber mesh was processed into a three-dimensional scaffold structure with a fiber diameter of approximately 20 μm. The external and internal diameters of TW were 8.0 and 3.7 mm, respectively. The molecular precursor solution was made by mixing Ca-EDTA/ amine ethanol solution and metaphosphate salt, and the Ca/P ratio was adjusted to 1.67. After immersing TW in the solution, it was heated at 600 °C for 2 hours. Six rabbits were assigned randomly to receive either HA-TW scaffold or TW on each side of the posterior mandible. The 3-mm-long toroidal titanium scaffolds were fitted into the osseous implant. Both TW- and HA-TW-fixed implants were then placed bilaterally with a transverse orientation. The animals were sacrificed at 12 weeks post-surgery, and new bone formation into the porous structure of TW and HA-TW was observed in non-decalcified sections. The newly formed bone rate in the HA-TW was significantly greater than that in the non-coated group (8.33±1.21 vs. 3.43±0.45 %, respectively). Furthermore, the rate of vertical bone regeneration was also significantly different between HA-TW and TW (63±15 vs. 33±8 %). Since the thin HA coating improved bone formation in externally placed TW, HA-TW is potentially useful for external bone augmentation.

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Unidirectional porous hydroxyapatite (UDPHAp) is a material whose microstructure consists of cross-sectional oval pores with a pore diameter in the range of 100-300 μm that penetrate through the material. UDPHAp has proven suitable for osteogenesis and angiogenesis. The present study was designed to evaluate the osteogenic effect of a newly developed UDPHAp as a carrier of recombinant human bone morphogenetic protein-2 (rhBMP-2) in a rat onlay graft model. UDPHAp was implanted beneath the calvarial periosteum of rats to simulate alveolar bone augmentation in a clinical condition. At 2 weeks after implantation, UDPHAp with rhBMP-2 resulted in active bone formation, and the augmented bone was connected directly with the original bone, whereas commercialized porous hydroxyapatite (PHAp) with rhBMP-2 showed little bone formation. These results suggest that UDPHAp in this model is suitable for onlay graft and is an effective biomaterial for the rhBMP-2 delivery system.

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Numerous disorders and types of injuries require bone tissue regeneration for the repair of bone defects. Previous attempts have been made to apply bone morphogenetic protein (BMP), a bioactive growth factor, to the defect site for bone reconstruction in various animal models. However, many of these studies evaluated the efficacy of BMP using texture and soft X-ray imaging performed after the laboratory animal was euthanized. As such, any attempts to observe the induction of new bone formation over a continuous time scale within the same laboratory animal has been difficult. Accordingly, a setup in which BMP-induced ectopic bone formation is assessed over the long term has become extremely important. To date, there are no reports to verify the long-term preservation of BMP-induced bone formation at sites of repair. In this study, we performed a long-term and continuous observation of new bone formation after the addition of BMP using a new three-dimensional micro X-ray computed tomography technology, R_mCT. BMP was implanted into a gap in the fascia of the femur in a mouse, and scanning using this new technology was continued for 320 days. The following tests were performed: (1) observation using 3-dimensional construction imaging; (2) measurement of the mean ratio of new bone volume to total volume, and (3) measurement of the density of new bone formation. From these tests, we observed that BMP-induced ectopic bone persists for up to 320 days, with minimal losses in bone volume or density, unlike previously accepted notions. We also present details of the structural changes in this ectopic bone.

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Current dental implant research aims at seeking an innovative surface able to promote a more favorable biological response to the cells and tissues at the bone-implant interface and to accelerate osseointegration. Anodic oxidation is a promising method for acquiring nanotube structures on the implant surface. In this paper, we modified the titanium surface using anodic oxidation to form nanotube structures on the surface and observed the surface by scanning electron microscopy (SEM). The bioactivity of the Ti implants was evaluated by simulated body fluid soaking test. We further sought to characterize the cellular and molecular responses of murine preosteoblast MC3T3-E1 cells to anodic oxidation modified titanium surface with a nanotube-texture. Gene expression of osteoprotegrin (OPG) was also evaluated by reverse transcription-polymerase chain reaction (RT-PCR) and quantitative real-time PCR. SEM showed that the inner diameter of the nanotubes was about 70nm, the wall thickness was around 20nm, and the depth was about 200nm. The simulated body fluid soaking test displayed that bone-like apatite was formed on the nanotube-textured Ti surface after immersion in simulated body fluid for two weeks, but not on the smooth surface Ti surface. The biocompatibility was investigated by an in vitro cell culture test. Cell morphology exhibited a more differentiated characteristic, and gene expression of osteogenic markers OPG was also remarkably upregulated by anodic oxidation modification. Based on these results, it can be concluded that bioactivity and osteogenic responses to the nanotube-structured Ti surface were better than to the smooth surface, and gene expression indicates that OPG activation may be responsible for this increased osteogenic differentiation.

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This study reported a 42-year-old male who suered a maxilla multiple fractures with additional complicating injuries. In this case, a maxillary contraction appliance was used as an alternative treatment with good results. This method provided fracture healing and functional occlusion. No facial surgery scar was left after treatment. Besides, the s, speaking allowing, chewing function returned to normal.

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Objective: To observe the effect of a fixed appliance with maxillary protraction in the treatment of skeletal Class III malocclusion, and to analyze soft and hard tissue variations. Material and methods: The study consisted of 78 cases with concave profile of skeletal Class III malocclusion, including 44 males and 34 females (aged 8-15years, mean 13.7years). According to the dental age, all cases were divided into four categories: Group A (n=14, mixed dentition); Group B (n=40, early permanent dentition, without mandibular second molar eruption); Group C (n=26, early permanent dentition, with mandibular second molars’ eruption) ; and Group D (n=24, permanent dentition). Cephalometric and hand-wrist radiographs were taken before treatment, while other cephalometric radiographs were taken after treatment. Statistical analysis was performed by software using SPSS 17.0. Results: The maxillary sagittal variation could be significantly affected by growth (ANS-Ptm) and forward movement of the maxilla (A-y, ANS-y). The direction of mandibular growth had been changed after treatment. The profile of soft tissue had also been remodeled. Conclusion: A fixed appliance with maxillary protraction was effective for patients with skeletal III malocclusion. The appliance could stimulate maxillary growth and inhibit mandibular protrusion in mixed dentition, early permanent dentition and some permanent dentition.

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The purpose of this study was to evaluate the surgical impact on the quality of life in 37 cases of patients who had resections of tongue cancer and reconstruction with a Radial Forearm Free Flap (RFFF). QOL was assessed by FACT-H&N and UW-QOL questionnaires prior to surgical treatment (Group 1) and twelve months postoperatively (Group 2). Thirty-seven of the forty-five questionnaires (82.2%) were returned. Tongue cancer impact QOL on patients’ physical, functional, social, and emotional well-being (PWB, SWB, EWB and FWB, respectively) were evaluated using the FACT-H&N questionnaire. Pain, followed by taste and saliva, were considered the most important factors by patients in both groups. In the UW-QOL, mood and shoulder were rated highest in Group 1, compared to pain and anxiety in Group 2. Despite some functional impairment, QOL was preserved after RFFF reconstruction following ablative surgery in patients with tongue cancer. RFFF for reconstruction of defects of tongue significantly influenced QOL.

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Malignant tumors arising from dentigerous cysts are classified as primary squamous cell carcinoma derived from an odontogenic cyst or as odontogenic carcinoma according to the 2005 WHO classification and are extremely rare. We report a malignant tumor arising from a dentigerous cyst in the right maxillary anterior teeth , together with a literature review. The patient was a 75-year-old man who visited a hospital with complaining of discomfort in the lingual part of the right maxillary anterior teeth. On panoramic radiography and plain computed tomography (CT), dentigerous cyst, keratocystic odontogenic tumor or ameloblastoma was suspected. The extirpated material was histopathologically diagnosed as an odontogenic carcinoma (in situ) arising from the dentigerous cyst. Postoperative ultrasonography (US) and contrast enhanced CT revealed no metastasis to the cervical lymph nodes. The patient is currently being followed up without resection or anticancer drug administration. Neither local recurrence nor metastases were observed 18 month after surgery.

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Odontogenic fibroma (OF) is a relatively rare benign tumor derived from odontogenic ectodermal mesenchymal tissue. It is divided into central (COF) or peripheral OF (POF) based on the affected area. Regarding its pathological features, OF can also be classified as epithelium-rich (WHO type) or epithelium-poor (simple type), depending on the amount of odontogenic epithelium in the tumor. There is limited information available about the latter type because of its low incidence. We report case of simple type COF apparently like POF. A 52-year-old Japanese male was suffering from tenderness at the right posterior maxilla during occlusion with his removable partial denture. The lesion was diagnosed as a simple type OF arising at the edentulous region around the right molar site of the maxilla. A tumor resection was performed, and there was no evidence of recurrence at his 18-month follow-up examination. In addition, we provide a review of the literature with the most up-to-date information about this lesion so that it can be diagnosed correctly.

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