Bone Marrow Stromal Cells Recovering the Periodontal Ligament in Mouse Experimental Occlusal Trauma Model

The 8th Conference of Asian International Association of Dental Traumatology (AADT) ; November 17-18, 2017 ; Mahidol University, Faculty of Dentistry, Bangkok, THAILAND

顎整形力を用いた上顎骨前方歯槽部の後方移動時におけるコルチコトミーの効果に関する研究

The dry skulls of two adult female Japanese macaques were used in this study of bone strains produced by corticotomy combined with orthopedics. The directions and magnitudes of the principal strains were measured using an eight-pair triaxial strain gauge rosette. While compressive strains were seen in the control study (orthopedic force alone before corticotomy), tensile strains were seen in the experimental study (orthopedic force after corticotomy) on the frontzygomatic suture, the lateral side of the zygomaticomaxillary suture of the zygomatic bone, and on the maxillary bone. Corticotomy, combined with the posterior transfer of the anterior segment, had the following effects : in the control study, traction was diffused though the maxillofacial structures, while in the experimental study, it did not readily diffuse because the compact bone was separated. This resulted in favorable conditions for the posterior transfer of the anterior maxillary segment between the maxilla proper and the maxillary alveolar bone which are connected only by trabecular bone. These results demonstrate the usefulness of combining a corticotomy with retraction of the maxillary anterior segment by orthopedic forces. A clinical case of Class II malocclusion is presented to illustrate what can be accomplished with treatment by corticotomy. The treatment objectives were achieved with improvement in the patient\u27s profile and in the function and esthetics of the dentition

Reactions to Bioabsorbable Suture Thread Embedded in Rat Subcutaneous Tissue

We examined the subcutaneous tissue reactions in rats to bioabsorbable suture thread using histopathological methods. Using Wister rats, Vicryl®, a bioabsorbable suture thread, was embedded into the subcutaneous tissue and histopathological examination was carried out after 4 weeks. Cholesterin crystals were used for the control. Furthermore, immunohistochemistry for CD68 was done. Histopathological examination showed proliferation of granulation tissues inboth experimental and control groups. The majority of cells in the granulation tissues were macrophages and giant cells. Fibroblasts were also observed in the proliferating granulation tissues surrounding the embedded bioabsorbable suturethread. Immunohistochemistry revealed that macrophages and giant cells were positive to CD68. The results suggest that the embedded bioabsorbable suture thread is not only fabricated to undergo absorption but also for phagocytosis bymacrophages and foreign body giant cells

エナメル上皮腫におけるHeat Shock Protein27の発現と細胞分化

The expression of HSP27 and some CKs were examined the 40 cases of typical solid/multicystic ameloblastoma using immunohistochemical techniques. In order to examine the relevance of HSP in cell differentiation, we focused on the cytoskeletal expression of CK. CK19 is a marker of typical odontogenic epithelium widely observed in follicular and plexiform types of ameloblastomas. Since staining with CK14 is one of the measures of the differentiation potential of squamous cells and is extensively expressed in both follicular and plexiform types, it implies that squamous differentiation of each type can occur. CK8 was strongly detected in tumor nests in plexiform type but weakly detected in follicular type. It was considered that the expression of HSP27 in plexiform type correlated with the expression of CK8 suggesting that HSP27 might have regulated the expression of CK8.2013博士（歯学）松本歯科大

Mandibular protrusion with late mandibular growth after orthodontic treatment

This report describes late mandibular growth of patient with mandibular protrusion af-ter orthodontic treatment including consideration about growth and development of man-dibular. A 15–year, 2 month old female patient presented with the chief complaint of crowding of upper and lower anterior teeth. The facial profile was concave type because of a skeletal Class 3 facial profile. The incisors were edge–to–edge bite. The molar relation-ship was Angle Class III protrusion. This patient was diagnosed as skeletal Class III pro-trusion with maxillary and mandibular incisors of edge–to–edge bite and crowding. After orthodontic treatment, the facial profile significantly improved and an acceptable occlusion was achieved. But 3 years later, late growth of mandibular was observed and the lower an-terior teeth were slightly crowding in retention phase

多形腺腫における細胞分化の促進因子としての Wnt シグナルの可能性

There are well known that Wnt signaling was some roles of cell differentiation at the development tissues, especially the oral and maxillofacial regions of some developmental stages. Therefore, to determine Wnt signaling in the pleomorphic adenoma tissues, we examined. The expression of Wnt1 and β-catenin as well as the distribution of various cytoskeletal proteins CK7 and CK13 was examined in 30 cases of pleomorphic adenoma by immunohistochemistry. Wnt1 was detected in almost all tumor cells. The peripheral columnar cells in squamous metaplasia and small cuboidal cells in duct-like structures were strongly positive to Wnt1. Although β-catenin was clearly localized on the cell membrane of tumor cells, nuclear translocation was observed in small cuboidal cells and in some basaloid cells. The immunofluorescent staining pattern of Wnt1 and CK7 as well as Wnt1 and CK13 was consistent with IHC results. Thus, in pleomorphic adenoma, Wnt is involved in tumor cell differentiation of peripheral columnar cells forming solid nests and small peripheral columnar cells forming duct-like structures. Moreover, among the three currently known Wnt pathways, β-catenin is the suggested pathway working during cell differentiation. Furthermore, peripheral columnar cells in solid tumor nests and in squamous metaplasia are governed by another Wnt pathway other than β-catenin. Therefore, Wnt signaling through β-catenin pathway may be involved in the ‘mixed’ differentiation characteristic of pleomorphic adenoma although another pathway may also be possibly working in other parts of the tumor tissue.2014博士（歯学）松本歯科大

Involvement of Heat-Shock Proteins During Periodontal Ligament Remodeling

Mechanical stress induces various molecules such as heat-shock protein (HSP), which causes structural changes in the proteins in periodontal ligament (PDL). We carried out an experiment to induce traumatic occlusion in mouse PDL and analyzed the expression of HSPs. HSPs investigated acts differently depending on the time of expression. HSPs are constitutively expressed in the PDL and defend cells from stress and maintain homeostasis under normal conditions. During bone addition to the PDL on the tension side, HSP27 and HSP47, HSP70 also acts as molecular chaperone, which assists the maturation of bone morphogenetic proteins and aids osteoblast activation. In HSP 70 and HSP 47, mechanical stress is applied to the PDL on the tension side for a short period of time for alveolar bone repairing, and when abnormality occurs in the collagen structure fibroblasts of PDL, it functions at the injured site, whereby extracellular that promotes abnormal collagen secretion and stores the modified protein in the endoplasmic reticulum, there by controlling the decalcification of PDL. In other words, HSP47 and HSP70 are expressed in PDL fibroblasts on the pressure side damaged by application of mechanical stress and contribute to the repair of collagen tissue by activating PDL fibroblasts, supporting recovery from cell damage

Bone Marrow Mesenchymal Cell Contribution in Maintenance of Periodontal Ligament Homeostasis

In general, remodeling phenomenon of the periodontal ligament (PDL) is occurring in all times. Thus, in the chapter, the word “maintenance” was used, and the chapter title is “Maintenance of Periodontal Ligament Homeostasis.” Our experimental data on the remodeling of the PDL with cell acceleration at the furcation area in this experimental model are recovered using the cells in situ and the bone marrow-derived cells (BMCs). BMC migration into the PDL tissues using green fluorescent protein (GFP) bone marrow-transplanted model mouse was examined. BMCs have abilities of cell migration and differentiation into tissues/organs in the body. The immunohistochemistry revealed that GFP-positive cells were detected in the PDL. GFP-positive cells were also positive to CD31, CD68, and Runx2 suggesting that fibroblasts differentiated into osteoclasts and tissue macrophages. In this way, Notch signaling involvement considered in our tentative examinations revealed that the experimentally induced periodontal polyp was examined; the cytological dynamics of the cells in granulation tissue are mainly from migration of undifferentiated mesenchymal cells of the bone marrow and differentiate into the tissue-specified cells. Furthermore, the data suggest that cell differentiation is due to Notch signaling

焼結ルチル二酸化チタン上の骨芽細胞様細胞の増殖およびアルカリホスファターゼ活性

The purpose of this study is creation of biomaterials from titanium dioxide (TiO2). This TiO2 has known for photocatalysis and osteogenesis. For the purpose of applying this function to orthodontic brackets and coating materials for implant, the relationship between surface of sintered and cell proliferation were examined. In addition, crystal structure and the surface property of sintering TiO2 were investigated. TiO2 were sintered at 1300°C for use as samples. We examined surface roughness, x-ray diffraction and scanning electron microscopy to make observations of the surface properties and texture. Moreover, mouse osteoblast-like cell line, MC3T3-E1 was cultured on sintered TiO2 in order to evaluate the cell proliferation and ALP. For the samples sintered at 1300°C, the crystalline phase of rutile-type TiO2 was confirmed.5000-fold magnified SEMimages of the surface of the unsintered samples, needle-like TiO2 crystals were pressure welded and showed mutual overlap, with pores occurring among the crystals. Sintering at 1300°C produced numerous small pores. Rutile TiO2 as a starting material was sintered at 1300°C and subjected to a cell culture experiment in which MC3T3-E1 cells were cultured on the sample, followed by viable cell counting and cell morphology observationon days 7, 14, 21, and 28 of culture. In the test of cell proliferation, sintered at 1300°C samples was found to remarkable cell proliferation even after time had passed. ALP activity of cells on 1300°C TiO2 sample, the values were 110% and 126% on days 14 and 28 of culture, respectively. These changes were calculated using polystyrene dish as the reference condition. Thus, TiO2 sintered at 1300°C showed good compatibility and increase in the ALP activity in MC3T3-E1 cells

Chapter 3 : Involvement of heat-shock proteins during periodontal logament remondeling.

Mechanical stress induces various molecules such as heat-shock protein (HSP), which causes structural changes in the proteins in periodontal ligament (PDL). We carried out an experiment to induce traumatic occlusion in mouse PDL and analyzed the expression of HSPs. HSPs investigated acts diff erently depending on the time of expression. HSPs are constitutively expressed in the PDL and defend cells from stress and maintain homeostasis under normal conditions. During bone addition to the PDL on the tension side, HSP27 and HSP47, HSP70 also acts as molecular chaperone, which assists the matu-ration of bone morphogenetic proteins and aids osteoblast activation. In HSP 70 and HSP 47, mechanical stress is applied to the PDL on the tension side for a short period of time for alveolar bone repairing, and when abnormality occurs in the collagen structure fi broblasts of PDL, it functions at the injured site, whereby extracellular that promotes abnormal collagen secretion and stores the modifi ed protein in the endoplasmic reticulum, there by controlling the decalcifi cation of PDL. In other words, HSP47 and HSP70 are expressed in PDL fi broblasts on the pressure side damaged by application of mechanical stress and contribute to the repair of collagen tissue by activating PDL fi broblasts, supporting recovery from cell damage.Edited by Jane Manakil,282p,illus. : London : IntechOpen, 2019