Platelet-rich fibrin (PRF) is the focus of research on the efficacy of regeneration of soft tissue and hard tissue in the dental field. PRF includes vascular endothelium growth factor (VEGF), platelet-derived growth factor (PDGF), insulin-like growth factor (IGF) and transforming growth factor-beta1 (TGF-beta 1). It is essential to quantitate the growth factors in PRF to evaluate its efficacy. In the present preliminary study, we quantitate TGF-beta1, VEGF and IGF-1 in PRF. Blood was collected from 10 healthy volunteers ranging in age from 25 to 51 years. The 10 ml blood samples were collected from the peripheral vein. After immediate centrifugation at 2,750 rpm for 10 minutes with 1000G, the platelet-poor plasma (PPP), which accumulated at the top, was collected. PRF was collected approximately 2 mm below its connection to the red corpuscle. The PPP and PRF were stored in tubes, and the quantity of TGF-beta1, VEGF and IGF-1 were quantified by ELISA. There were no significant differences in the level of IGF-1 in the PPP and PRF. However, the levels of TGF-beta1 and VEGF in PRF were significantly higher than in PPP. These results suggest that PRF has some ability to stimulate soft tissue healing and bone regeneration.

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The mandible is a unique bone with a two-layered structure comprising the alveolar area that holds the teeth and the base of the mandible. When teeth are lost, the alveolar area is quickly resorbed, and the internal structure of the mandible changes greatly. Quantitative assessment of changes in the bone microarchitecture that occur with tooth loss is thus imperative. We therefore quantitatively assessed bone mineral density (BMD) and biological apatite (BAp) crystalline orientation in human edentulous mandibles and elucidated the structural characteristics of human edentulous mandibles. Japanese edentulous mandibles were divided into samples with a high and well-rounded alveolar area and thin cortical bone in the alveolar area (α-type), thick cortical bone (β-type), and those with a low and flat alveolar area (γ-type). BMD and BAp crystalline orientation were measured in the alveolar area and base of the mandible of the site corresponding to the first molar (the region of interest). Although BMD did not differ by site, comparisons of the different types revealed that BMD was high in the α-type and low in the β- and γ-types. BAp crystalline orientation in the alveolar area was observed in the vertical direction to the virtual occlusal plane (Y-axis) and buccalingual direction (Z-axis) in the α-type, whereas weak preferential orientation in the mesiodistal direction (X-axis) was observed in the β- and γ-types. BAp crystals in the base of the mandible showed uniaxial preferential alignment along the X-axis in all three sample types (p < 0.05). These findings demonstrate that most of the human edentulous mandible develops long bone-like characteristics with resorption of the alveolar area and that orientation in the alveolar area varies with morphological changes in the alveolar bone.

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The aim of this study was to determine the maxillary expansion index (MEI) for Pakistani population. Also to determine the sexual disparities in sum of incisors perimeter, arch width and expansion indices of maxillary arch. Hirox digital stereomicroscope was used for the fabrication of the digital models. The estimated sample size was 128 Pakistanis (64 females and 64 males; age range from18 -24 years). The perimeters of the maxillary permanent incisors, as well as intercanine, interpremolar, and intermolar arch widths, were measured on digital dental models. Significant sexual disparities were observed (***p < 0.001). There was significant difference observed in arch length and arch perimeter group of maxilla. For the prediction of ideal arch width in intercanine, interpremolar, and intermolar region to be achieved at the finishing stage, orthodontist can forecast the arch width before the initiation of orthodontic treatment. The new formula and the new indexes of arch width can be a helpful adjunct in the orthodontic treatment.

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In the present study, collagen (Coll) or fibronectin (FN) was immobilized onto poly(lactic acid)/ε-caprolactone (PLCL) copolymer surface and the attachment and proliferation of osteoblast-like cells on Coll or FN immobilized PLCL (Coll-PLCL, FN-PLCL) were evaluated. Coll or FN immobilized PLCL was prepared through a condensation reaction between the carboxylic acid groups on the hydrolyzed PLCL (PLCL-COOH) surface and the amino groups of Coll or FN using water soluble carbodiimide. The contact angle of the PLCL-COOH, Coll-PLCL and FN-PLCL surfaces with respect to double distilled water significantly decreased compared with PLCL (p<0.05). Number of attached cells onto Coll-PLCL or FN-PLCL films was significantly greater than on PLCL films from at the time of 90 min to 7days (p<0.05). The morphological differences of attached osteoblast-like cells were observed between PLCL films and Coll-PLCL or FN-PLCL films at the early stage of cell assay. The cell attached on Coll-PLCL and FN-PLCL films appeared more flat than on PLCL films. Additionally, many actin filaments and stress fibers were observed on Coll-PLCL or FN-PLCL films during 3 and 7 days of cell assay. Actin filaments and stress fibers were few on PLCL films. These data demonstrated the effectiveness of collagen and fibronectin immobilization of PLCL for cell attachment and proliferation. This indicates that collagen or fibronectin immobilization of PLCL films was effective for biological activities of osteoblast-like cells.

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Our previous research reports that NaOH treatment leads to the formation of a Ti-O-Na titanate layer on the titanium-6-aluminium-4-vanadium (Ti6Al4V) surface. However, this titanium nanosheets (TNS) hydrogel layer is so brittle that it easily detaches from the implant and can cause many problems, including degradation in the living body due to inhomogeneous composition distribution. The aims of the present study were to investigate combined alkali-treatment of Ti6Al4V alloy and then heated and evaluate the ability of this modified surface to affect osteogenic differentiation of rat bone marrow (RBM) cells, to increase the success rate of titanium implants. We fabricated TNS on titanium alloy surfaces by NaOH treatment prior to heat treatment at 600 °C, and determined RBM cell properties and differentiation potential on the surface in comparison to untreated control surfaces. The nanoscale network structures formed by alkali etching markedly enhanced RBM cell adhesion and osteogenic-related gene expression. Other cell behaviors, such as proliferation, alkaline phosphatase activity, osteocalcin deposition and mineralization, were markedly increased on the TNS-modified Ti6Al4V with heat treatment. Our results suggest that titanium implants modified with nanostructures promote osteogenic differentiation, which may improve the biointegration of these implants into the alveolar bone.

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The aim of this study was to investigate the influence of ultrasonic surgical method (piezoelectric surgery) on invasions of bone structure in early stages and the subsequent healing process of bone defects of rat calvaria as compared with that of rotary cutting using an appropriate rotation speed. Thirteen-week-old male Sprague-Dawley rats were used in this study. Bone defects were prepared in rat calvaria using either an ultrasonic surgical instrument with an ultrasonic insert tip (Ui) or a handpiece with a round bur (Rb) as a rotary cutting instrument (control). Morphological evaluations of the cutting surfaces in the bone defects were assessed by scanning electron microscope (SEM) and confocal laser microscope (CLM) observation. The degree of invasions of the bone structure in the early stages after bone defects were made was assessed by the ratio of empty osteocyte lacunae relative to the total number of osteocytes. The process of bone healing was analyzed by histological observation, immunohistochemical staining with proliferating cell nuclear antigen (PCNA) and osteocalcin (OC), and ratio of PCNA-positive cells. Many fine, parallel streaky cutting traces were observed in the Ui groove surfaces, whereas the Rb groove surfaces were flat and no parallel cutting traces were observed. The arithmetic average roughness of the Ui group (10.06 ± 1.96 µm) was significantly higher than that of the Rb group (2.52 ± 0.16 µm) (p < 0.05). During the entire observation period, no differences in histological observation and immunohistochemical staining were observed between the Ui and Rb groups. No significant differences were recognized in the ratio of empty lacunae and PCNA-positive cells between the Ui and Rb groups. In the present study, there were no appreciable differences in the invasions of bone structure in the early stages and the subsequent healing process of the bone defects of rat calvaria between ultrasonic surgical method and rotary cutting method.

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To observe the effects of reduced glutathione on promoting osseointegration of titanium implants in New Zealand rabbits with type I diabetes mellitus and to provide novel evidence for improving implants osseointegration. Diabetes mellitus models were established by injecting alloxan (80 mg/kg) into New Zealand rabbits. Success was verified by the blood glucose level. Titanium implants were then placed in the rabbits’ femoral epiphysis. Intravenous glutathione (GSH, 30 mg/kg) or saline, respectively, was started. The rabbits were divided into four groups: GSH-treated diabetes mellitus (GSH+DM), diabetes mellitus (DM), GSH-treated normal rabbits (GSH), normal control rabbits (NC). Four weeks after surgery, the rabbits were evaluated via general observation, micro-computed tomography (micro-CT), H&E staining and bone morphogenetic protein 2 (BMP-2) immumohistochemical staining. In results, general observation and micro-CT showed that wounds had healed, no implants had loosened, and there was good synostosis in all groups. Micro-CT also revealed that peri-implant threaded bone density was higher than that in peri-implant cancellous bone and was similar to that in femoral cortical bone. The implants tightly fused with surrounding bone tissue. HE staining revealed that large numbers of bone trabeculaes, osteoblasts, and chondrocytes in the GSH+DM group and granulation tissue, mononuclear macrophages, and multinucleated giant cells in the DM group. New bone trabecular formation was rare. There was greater expression of BMP-2 in the GSH+DM group than in the GM group. The results suggest that GSH promotes new peri-implant bone formation and osseointegration in diabetic rabbits.

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Our goal was to compare clinical and functional results of the infrahyoid myocutaneous flap (IMF) with those of the radial forearm free flap (RFFF) for partial tongue reconstruction. Between January 2005 and June 2012, patients who had received an IMF or a RFFF reconstruction for cT1-2 tongue carcinoma were included, their medical records were reviewed, and they were asked to complete the University of Washington Quality of Life (UW-QoL) version 4 questionnaire at least 12 months postoperatively. Compared to patients with a RFFF reconstruction, patients treated with an IMF had significantly shorter operation time (p<0.001), less hospital cost (p<0.001) and shorter postoperative stay (p<0.001). There were no apparent differences in other scales between the two groups. The mean composite score for the two groups was 88.4 (SD: 14.9) and 86.4 (SD: 15.3), respectively, the finding was not significant (p=0.784). Patients with an IMF reconstruction had significantly better shoulder function, there were no significant differences regarding other domains between the two groups. Compared to RFFF, IMF was a reliable procedure for partial tongue reconstruction.

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The purpose of this study was to investigate buccolingual and diagonal crown dimensions of the maxillary and mandibular arch in relation to arch perimeter, arch length and arch width groups. The sample consisted of 128 subjects ranging in age from 18 to 24 years. A Hirox digital stereomicroscope (SM) (HIROX KH7700 Japan) was used to construct digital models. A total of 10,752 variables were measured. Sex differences in the buccolingual and diagonal crown dimensions were explored. Analysis of variance (ANOVA) was applied to evaluate the differences between arch length, arch perimeter and arch width groups. Males had significantly larger mean values for buccolingual and diagonal crown dimension with than females (p d” 0.05) for both maxillary and mandibular arches. There were significant differences observed in large vs. small, average vs. small and average vs. large arch length groups (p d” 0.05) in both maxilla and mandible in relation to buccolingual and diagonal crown dimension. Our results indicate the buccolingual and diagonal crown dimension difference in relation to various arch length, arch perimeter and arch width group of maxilla and mandible. Thus it may be helpful for orthodontic case investigation and treatment.

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We demonstrated some different contrasts of cat mandibular squamous cell carcinoma using parametric X-ray radiation at the Laboratory for Electron Beam Research and Application at Nihon University (LEBRA-PXR). A conventional X-ray image revealed a bone tumorous lesion in the mandible. LEBRA-PXR images (20, 25 and 30KeVs) showed some contrasts related to the wavelengths. LEBRA-PXR displayed contrasts which differed from those of conventional X-ray images, suggesting LEBRA-PXR may be useful for diagnostic imaging as a new X-ray source.

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