Signs, Symptoms, and Morphological Features of Idiopathic Condylar Resorption in Orthodontic Patients : A Survey-Based Study

Background: Idiopathic condylar resorption (ICR) is an aggressive degenerative disease of the temporomandibular joint that is most frequently observed in teenage girls. However, no specific cause of ICR has been identified. To explore the specific causes of the onset and progression of ICR, we performed a survey-based study on ICR in orthodontic patients and described its subjective symptoms, clinical signs, and condylar morphological features. Methods: A total of 1735 participants were recruited from 2193 orthodontic patients. For each participant, subjective symptoms and clinical signs of temporomandibular disorders (TMDs) were evaluated through clinical examination and a questionnaire. Furthermore, three-dimensional computed tomography (CT) was performed to diagnose ICR. Results: Among the 1735 patients evaluated, ICR was present in two male and ten female patients. All 12 patients had maxillary protrusion and an anterior open bite. Four patients with ICR underwent orthodontic treatment. Based on CT findings, patients with ICR had significantly different condylar sizes and shapes from patients with TMDs alone. Conclusions: The coexistence of intrinsic and extrinsic factors, such as sex-hormone imbalance and a history of orthodontic treatment, might lead to the onset of ICR. We suggest that growing patients suspected of having ICR should undergo CT evaluation because CT findings may precede clinical symptoms and signs

A Collaborative Educational Program Involving the Reuse of Timbers from the Old Farm Houses Damaged by the Earthquakes in Niigata

IACEE 11th World Conference on Continuing Engineering EducationIn this educational program, students, inhabitants and professionals worked together discussing the planning and design for wooden arcades, called locally Gangi, and actually built them together as a part of various town planning schemes. The Chuetsu area of Niigata JAPAN was struck by strong Earthquakes in 2004 and 2007. After the earthquakes, many damaged houses were demolished and a lot of materials like timbers were discarded. We kept a number of old timbers of damaged houses for re-use in the new wooden arcades. We tried to sustain the memory of the old buildings and to prevent these materials from being thrown away. Students measured the old timbers and made up a list of them as materials in the design of the Gangi. We requested that the students re-use the old timbers in their design. At the design presentation stage, we were able to find various ways of reusing the old timbers. One team created a design using the old timbers for the main structures like posts and beams. The other team used them as non-stressed timbers or for decorative use. The inhabitants evaluated the teams proposing the positive timber usage. We successfully built two new Gangi and 24 ornamental features re-using the old timbers. There were some practical problems in using the old timbers. They contained many nails and metals, and most of them were partially decayed. Moreover, we could not cut them into adequate sizes easily. Additionally the constructor misunderstood this idea and proposed to use only new materials instead of the old ones. In this educational program, we thought it was necessary to keep to the traditional landscape using natural materials with their essential qualities and shapes. A good way to solve these practical problems, was the collaboration with local professionals, and the sharing of ways of thinking with inhabitants, professionals, and students at every opportunity by discussion. Our educational program is has not been temporary but has been made up of various ongoing activities. This program has lasted for twelve years and we have successfully kept a good relationship going among the students, inhabitants and professionals involved.Distance Learning and Professional Education ; International Association for Continuing Engineering Educatio

Thread shape, cortical bone thickness, and magnitude and distribution of stress caused by the loading of orthodontic miniscrews : finite element analysis

Cortical bone thickness is assumed to be a major factor regulating miniscrew stability. We investigated stress distribution in two miniscrews with different thread shapes (type A and B) and in cortical bone of three different thicknesses using three-dimensional (3D) finite element (FE) models. More specifically, 3D FE models of two different miniscrews were created and placed obliquely or vertically into a cylindrical bone model representing different cortical bone thicknesses. When force was applied to the miniscrew, the stress distribution on the screw surface and in the peri-implant bone was assessed using FE methodology. Miniscrew safety was evaluated using a modified Soderberg safety factor. Screw head displacement increased with a decrease in cortical bone thickness, irrespective of screw type. The smallest minimum principal stresses on the screw surfaces remained constant in type A miniscrews on changes in cortical bone thickness. Minimum principal stresses also appeared on the cortical bone surface. Lower absolute values of minimum principal stresses were seen in type A miniscrews when placed vertically and with upward traction in obliquely placed type B miniscrews. Both miniscrews had acceptable safety factor values. Taken together, orthodontists should select and use the suitable miniscrew for each patient in consideration of bone properties

変形性顎関節症の進展におけるp21の免疫調節作用

Objective: We aimed to identify the immunoregulatory role of the cyclin-dependent kinase inhibitor p21 in the homeostasis of mandibular condylar cartilage affected by mechanical stress. Materials and Methods: Ten C57BL/6 wild-type (WT) and ten p21–/– mice aged 8 weeks were divided into the untreated and treated groups. In the treated groups, mechanical stress was applied to the temporomandibular joint (TMJ) through forced mouth opening for 3 h/day for 7 days. The dissected TMJs were assessed using micro-CT, histology, and immunohistochemistry. Results: Treated p21–/– condyles with mechanical stress revealed more severe subchondral bone destruction, with thinner cartilage layers and smaller proteoglycan area relative to treated WT condyles; untreated WT and p21–/– condyles had smoother surfaces. Immunohistochemistry revealed significant increases in the numbers of Caspase-3, interleukin-1β, matrix metalloprotease (MMP)-9, and MMP-13 positive cells, and few aggrecan positive cells, in treated p21–/– than in treated WT samples. Moreover, the number of TUNEL positive cells markedly increased in p21–/– condyles affected by mechanical stress. Conclusion: Our findings indicate that p21 in chondrocytes contributes to regulate matrix synthesis via the control of aggrecan and MMP-13 expression under mechanical stress. Thus, p21 might regulate the pathogenesis of osteoarthritis in the TMJ

Macrophage Motility in Wound Healing Is Regulated by HIF-1α via S1P Signaling

Accumulating evidence indicates that the molecular pathways mediating wound healing induce cell migration and localization of cytokines to sites of injury. Macrophages are immune cells that sense and actively respond to disturbances in tissue homeostasis by initiating, and subsequently resolving, inflammation. Hypoxic conditions generated at a wound site also strongly recruit macrophages and affect their function. Hypoxia inducible factor (HIF)-1α is a transcription factor that contributes to both glycolysis and the induction of inflammatory genes, while also being critical for macrophage activation. For the latter, HIF-1α regulates sphingosine 1-phosphate (S1P) to affect the migration, activation, differentiation, and polarization of macrophages. Recently, S1P and HIF-1α have received much attention, and various studies have been performed to investigate their roles in initiating and resolving inflammation via macrophages. It is hypothesized that the HIF-1α/S1P/S1P receptor axis is an important determinant of macrophage function under inflammatory conditions and during disease pathogenesis. Therefore, in this review, biological regulation of monocytes/macrophages in response to circulating HIF-1α is summarized, including signaling by S1P/S1P receptors, which have essential roles in wound healing

矯正治療中に歯肉退縮した下顎中切歯に対して結合組織移植を行った長期保定症例

歯肉退縮は，矯正治療中や治療後にしばしば生じるリスクのひとつであり，歯根面の露出により審美障害ならびに知覚過敏や根面う蝕などの問題を誘発する． 歯肉退縮の予防を目的とした，矯正治療前の歯周外科処置も報告されているが，現時点では一般的ではなく，実際に歯肉退縮が発生した後，結合組織移植術（CTG）などの歯周形成外科手術によって対応しているのが現状である． 今回我々は，歯性上顎前突患者の矯正治療中に下顎左側中切歯に生じた歯肉退縮に対して，1年10か月間の矯正治療終了後にCTGを施行し，術後6年経過した現在も歯肉退縮の再発を認めず，良好な状態が維持された症例を経験したため報告する．Gingival recession is one of the common risks in clinical orthodontics, and it results in dentinal hyperesthesia and root caries with esthetic problems. Periodontal surgical therapy including connective tissue graft (CTG) has not been routinely performed to prevent gingival recession before orthodontic treatment, and CTG has been conducted when causing gingival recession after orthodontic treatment. In this study, we report a case of dental maxillary protrusion who induced gingival recession in the left lower central incisor during orthodontic treatment. After 1-yesr 10-month orthodontic treatment, a subepithelial CTG procedure was performed. Healing was uneventful, and the grafted site showed a favorable outcome at 6 years postoperatively

Macrophage Motility in Wound Healing Is Regulated by HIF-1α via S1P Signaling

Accumulating evidence indicates that the molecular pathways mediating wound healing induce cell migration and localization of cytokines to sites of injury. Macrophages are immune cells that sense and actively respond to disturbances in tissue homeostasis by initiating, and subsequently resolving, inflammation. Hypoxic conditions generated at a wound site also strongly recruit macrophages and affect their function. Hypoxia inducible factor (HIF)-1α is a transcription factor that contributes to both glycolysis and the induction of inflammatory genes, while also being critical for macrophage activation. For the latter, HIF-1α regulates sphingosine 1-phosphate (S1P) to affect the migration, activation, differentiation, and polarization of macrophages. Recently, S1P and HIF-1α have received much attention, and various studies have been performed to investigate their roles in initiating and resolving inflammation via macrophages. It is hypothesized that the HIF-1α/S1P/S1P receptor axis is an important determinant of macrophage function under inflammatory conditions and during disease pathogenesis. Therefore, in this review, biological regulation of monocytes/macrophages in response to circulating HIF-1α is summarized, including signaling by S1P/S1P receptors, which have essential roles in wound healing

Macrophage Motility in Wound Healing Is Regulated by HIF-1α via S1P Signaling

Accumulating evidence indicates that the molecular pathways mediating wound healing induce cell migration and localization of cytokines to sites of injury. Macrophages are immune cells that sense and actively respond to disturbances in tissue homeostasis by initiating, and subsequently resolving, inflammation. Hypoxic conditions generated at a wound site also strongly recruit macrophages and affect their function. Hypoxia inducible factor (HIF)-1α is a transcription factor that contributes to both glycolysis and the induction of inflammatory genes, while also being critical for macrophage activation. For the latter, HIF-1α regulates sphingosine 1-phosphate (S1P) to affect the migration, activation, differentiation, and polarization of macrophages. Recently, S1P and HIF-1α have received much attention, and various studies have been performed to investigate their roles in initiating and resolving inflammation via macrophages. It is hypothesized that the HIF-1α/S1P/S1P receptor axis is an important determinant of macrophage function under inflammatory conditions and during disease pathogenesis. Therefore, in this review, biological regulation of monocytes/macrophages in response to circulating HIF-1α is summarized, including signaling by S1P/S1P receptors, which have essential roles in wound healing

Macrophage Motility in Wound Healing Is Regulated by HIF-1 alpha via S1P Signaling

Accumulating evidence indicates that the molecular pathways mediating wound healing induce cell migration and localization of cytokines to sites of injury. Macrophages are immune cells that sense and actively respond to disturbances in tissue homeostasis by initiating, and subsequently resolving, inflammation. Hypoxic conditions generated at a wound site also strongly recruit macrophages and affect their function. Hypoxia inducible factor (HIF)-1 alpha is a transcription factor that contributes to both glycolysis and the induction of inflammatory genes, while also being critical for macrophage activation. For the latter, HIF-1 alpha regulates sphingosine 1-phosphate (S1P) to affect the migration, activation, differentiation, and polarization of macrophages. Recently, S1P and HIF-1 alpha have received much attention, and various studies have been performed to investigate their roles in initiating and resolving inflammation via macrophages. It is hypothesized that the HIF-1 alpha/S1P/S1P receptor axis is an important determinant of macrophage function under inflammatory conditions and during disease pathogenesis. Therefore, in this review, biological regulation of monocytes/macrophages in response to circulating HIF-1 alpha is summarized, including signaling by S1P/S1P receptors, which have essential roles in wound healing

HIF-1 alpha controls palatal wound healing by regulating macrophage motility via S1P/S1P(1) signaling axis

Objectives To investigate the role of hypoxia-inducible factor 1 alpha (HIF-1 alpha) signaling, the expression profile of M1 and M2 macrophages, and the role of the sphingosine 1-phosphate (S1P)/S1P receptor system in palatal wound healing of heterozygous HIF-1 alpha-deficient (HIF-1 alpha HET) mice. Materials and methods HIF-1 alpha HET and wild-type (WT) littermates underwent palatal tissue excision at the mid-hard palate. Histological analysis, immunostaining, real-time PCR, Western blotting (WB), and cellular migration assays were performed to analyze wound closure and macrophage infiltration. Results DMOG pretreatment showed an acceleration of palatal wound closure in WT mice. In contrast, the delayed palatal wound closure was observed in HIF-1 alpha HET mice with diminished production of Col1a1, MCP-1, and MIP-1 alpha, compared with WT mice. Decreased infiltration of M1 macrophage (F4/80(+)TNF-alpha(+), F4/80(+)iNOS(+)) and M2 macrophage (F4/80(+)Arginase-1(+), F4/80(+)CD163(+)) was observed. The numbers of F4/80(+)S1P(1)(+) macrophages of HIF-1 alpha HET wounded tissues were significantly lower compared with WT tissues. S1P treatment of bone marrow macrophages (BMMs) significantly upregulated expression of S1P(1) in WT mice compared with HIF-1 alpha HET. Phosphorylation of MAPK rapidly decreased in BMMs of HIF-1 alpha HET mice than in BMMs of WT mice by S1P stimulation. Moreover, S1P enhanced HIF-1 alpha expression via S1P(1) receptors to affect macrophage migration. Conclusions HIF-1 alpha deficiency aggravates M1 and M2 macrophage infiltration and controls macrophage motility via S1P/S1P(1) signaling. These results suggest that HIF-1 alpha signaling may contribute to the regulation of palatal wound healing