Ligament Bone Research Articles

Membrane Guided Regeneration in Periodontal Tissues

Periodontal regeneration is the restoration of lost periodontium or supporting tissues and includes the formation of new alveolar bone, new cementum and new periodontal ligament. The concept of GTR is based on the exclusion of gingival connective tissue cells and prevention of epithelial down growth into the wound, thereby allowing cells with regenerative potential (PDL and bone cells) to enter the wound first. GTR consists of placing barriers of different types to cover the bone and periodontal ligament thus temporarily separating them from gingival epithelium. Excluding the epithelium and gingival connective tissue from the root surface during the post-surgical healing phase not only prevent epithelial migration into the wound but also favors repopulation of the area by cells from the periodontal ligament and bone. Purpose and Scope -This review discusses the rationale for using guided tissue regeneration therapy. The review not only attempts to clarify the concept of selective tissue regeneration using non-resorbable and resorbable barriers, but to discuss differences in healing events after treatment with the two types of barriers together with their significance in periodontal therapy. At present, barrier membranes have potential clinical use in promoting periodontal tissue regeneration if patients to be so treated are selected appropriately. Research is still necessary to determine the critical period for guiding the ingrowth of new attachment forming cells and also to further clarify the concept of GTR involving the "wrong cell type" which inhibits periodontal tissue regeneration.

Injury Thresholds of Knee Ligaments Under Lateral–Medial Shear Loading: An Experimental Study

Objective: Knee ligament injuries frequently cause devastating impairment to the injured. In car–pedestrian impact accidents, lateral–medial shear displacement is one of principal mechanisms of knee ligament injuries. The current study aims to investigate injury thresholds of knee ligaments under lateral–medial shear loading to improve pedestrian safety. Methods: Ten isolated human knee joints without surrounding muscles were tested under dynamic lateral–medial shear loading in 2 groups: 3 left knee joints were tested in the shearing of medial tibial translation, and other knee joints were tested in lateral tibial translation. Based on combined analysis of experimental videos and force curves, the primary failure time of knee ligaments and the corresponding shear displacement were determined. Results: Under lateral tibial translation and medial tibial translation, both primary injury types of knee ligaments and force curves showed essential differences. It appears that the majority of primary failure modes were anterior cruciate ligament (ACL) injury when the tibia was displaced medially and posterior cruciate ligament (PCL) injury when the tibia was displaced laterally. Overall experimental results indicated that the injury threshold of the knee joint under lateral–medial shear loading varied from 11.4 to 17.6 mm, with an average level approximately 14.3 mm. Conclusion: Based on the bone–ligament–bone complex experiment of the knee, we present injury occurrences of the knee joints in lateral and medial shear loading. The testing data provide a basis for improving knee injury criteria that regulate passenger cars to reduce their aggressiveness to pedestrians. Supplemental materials are available for this article. Go to the publisher's online edition of Traffic Injury Prevention to view the supplemental file.

Three-dimensional finite element analysis of removable partial denture with periodontally compromised abutments

To evaluate three-dimensional (3D) finite element (FE) modeling of different periodontally compromised unilateral distal extension removable partial denture (RPD) abutments using the data of a 3D non-contact digitizing scanner. FE models were established, and the following structures were simulated in the models: alveolar bone, mucosa, abutments, periodontal ligaments, framework and artificial teeth. The alveolar bone and periodontal ligaments around the distal abutment in the three models were designed as normal, with bone defect and with periodontal ligaments defect respectively.Vertical or buccally inclined forces of 50, 100, 100 N were applied on the artificial teeth of the RPD and the stress distributions on the supporting tissues were calculated. Under vertical loading, the maximal stress on the alveolar bone of the abutment were as follows: periodontal ligaments defect model (3.57 MPa) > bone defect model (3.21 MPa) > normal model (2.63 MPa). Under buccally inclined loading, the maximal stress on the alveolar bone of the abutment were as follows: periodontal ligaments defect model (2.50 MPa) > bone defect model (2.41 MPa) > normal model (1.79 MPa). Under buccally inclined loading, the stresses on distal aspects of the residual alveolar ridge were higher than that of the vertical loading model. 3D non-contact digitalizing scanner was useful for the finite element modeling process of removable partial denture.

Traumatismes du carpe chez l’enfant

Carpal injuries in children are uncommon. Radiographic diagnosis can be difficult because of late ossification of carpal bones. Scaphoid fracture occurs in 3% of hand and wrist fractures. Fractures in the distal third or at the waist are the most frequent fracture sites. In case of clinical and X-rays presumption, CT-scan and MRI often diagnose scaphoid fractures. Orthopaedic treatment with closed cast for 8 weeks, or more for adolescents, gives a high rate of union in non-displaced or minimally-displaced fractures. Non-union is the most frequent complication. Closed cast can be the treatment of non-union in absence of humpback or DISI deformity. Other carpal bone fractures or ligament injuries of the wrist in children are uncommon and CT-scan, MRI or arthroscopy can be useful in case of clinical suspicion.

Variation of the effect of calcium phosphate enhancement of implanted silk fibroin ligament bone integration

In this article, low crystallinity hydroxyapatite (LHA) is developed and utilized to modify silk fibroin scaffolds which are applied to repair bone/ligament defects successfully. It can promote osteogenesis which is authenticated through in vitro and in vivo tests. The scaffold is an efficient carrier, supporting cell proliferation and differentiation. Meanwhile, cytocompatibility and osteoblastic gene expressions (RUNX2 and osteocalcin, for example) of rabbit's bone marrow derived mesenchymal stem cells (MSCs) are significantly boosted on LHA/silk scaffold. Further, for animal trial, almost 60% of bone volume and 80% of original mechanical strength are recovered after 4 months' bone/ligament regeneration in bone tunnel of rabbit model, where significant amount of bone tissue regeneration is also confirmed by data of histological evaluation and micro computed tomography (μ-CT). Hence, the invented scaffold is applicable for ligament/bone regeneration in future lager animal and clinical trials.

Severe Bone Loss induced by Orthodontic Elastic Separator: A Rare Case Report

A displaced orthodontic elastic separator was proposed as being the source of a gingival abscess that progressed to severe bone loss and exfoliation in a healthy adolescent patient with sound periodontal status prior to commencement of orthodontic treatment. After 1 year of undergoing orthodontic treatment, the patient presented with dull pain and mobility in the left upper permanent molar for which there was no apparent etiology. On clinical examination, the patient had gingival inflammation, associated with a deep pocket and severe mobility (grade III) in relation to the same teeth. Radiographic examination of an orthopantomogram and intraoral periapical radiography (IOPAR) revealed a chronic periodontal abscess with severe necrosis of the periodontal ligament and severe alveolar bone loss. A radiopaque mass on the distal surface below the cementoenamel junction (CEJ) was also observed. The patient was referred to the department of periodontics for assessment and appropriate treatment. On curettage, it was found that there was orthodontic elastic separator which was displaced subgingivally.

Differences in collagen distribution of healthy and regenerated periodontium. Histomorphometric study in dogs.

Previous studies have shown that there is a relationship between periodontal disease and the distribution of collagen fibers. This study evaluated the distribution of collagen types I and III in regenerated bone and periodontal ligament, comparing them to the tissues near the regenerated area and to the healthy periodontium. In the third (P3) and fourth (P4) mandibular premolars of 5 healthy mongrel dogs, bilaterally, buccal class 2 furcation lesions were surgically created and chronified for 3 weeks. After that, full flaps were elevated and expanded polytetrafluoroethylene (e-PTFE) membranes were adapted, sutured and recovered by the flaps. Two weeks after surgery, two membranes on the same side were removed and the other membranes were removed four weeks after surgery. The dogs were euthanized at 12 weeks following placement of the e-PTFE membranes. P3 and P4 teeth as well as the second premolars (healthy control teeth) and their periodontal tissues were removed and histologically processed for Collagen Quantification (COLQ). The amount of type III collagen was higher in native bone compared to the regenerated area. For periodontal ligament, COLQ for type I collagen showed statistically significant differences (Tukeys's Multiple Comparison, p⟨0.05) between the regenerated groups and the control group. These differences were not found for type III COLQ. There are significant differences in collagen distribution among the regenerated, native and control tissues. Membrane removal 2 or 4 weeks postoperatively did not influence the collagen composition.

Preparation and Characterization of Alveolar Bone and Periodontal Ligament Interface Scaffolds

To mimic the alveolar bone and periodontal ligament interface, a chitosan(CS for short) composite polysaccharide scaffold was fabricated which was cross-linked with sodium alginate(SA for short). The conditions of physical crosslinking in the scaffolds were discussed. By characterization after biomineralization, it turns out that pH=5.0 and 40min crosslinking time can make for crosslinking. Better crosslinking makes the material more antiswelling and give more compressive strength. In the other hand, the biomineralization can improve the physical properties of the material. We hope that after further research it can come to a scaffold material with good properties.

Folic acid: A positive influence on periodontal tissues during health and disease

Periodontal disease is a multifactorial disease, the origin of which remains obscure. However, the manifestation and progression of periodontitis is influenced by a wide variety of determinants including social and behavioral factors, systemic factors, environmental and genetic factors. Periodontal tissue integrity is dependent on the adequate intake of proteins, carbohydrates, fats, vitamins, and mineral salts. Chronic deficiencies in the availability of one or more of these nutrients are expected to produce pathological alterations in the expression and progression of periodontal disease. Folic acid, also known as vitamin B 9 or folacin, is one such vitamin that is essential for numerous bodily functions ranging from nucleotide biosynthesis to the remethylation of homocysteine. Folic acid deficiency causes absence of keratinization of gingival surface, decreased resistance to infection, necrosis of gingiva, periodontal ligament, and alveolar bone destruction in animals and humans. This may be accompanied by ulcerative glossitis and cheilitis. Repair and maintenance of periodontal tissues generates a high turnover rate of squamous epithelium and without folic acid, epithelial cells do not divide properly. Folic acid deficiency is the most common nutrient deficiency in the world. Organic nitrites, nitrous oxide, cyanates, and isocyanates found in cigarette smoke have been shown to interact with folic acid, transforming them into biologically inactive compounds and thereby leading to lower folic acid levels in serum, red blood cells, and respiratory tract. Folic acid supplementation as an adjunct in the management of periodontal disease in smokers will prove to have beneficial effect on the periodontal tissues during repair and turnover.

Biomechanical validation of an artificial tooth–periodontal ligament–bone complex for in vitro orthodontic load measurement

To develop an artificial tooth-periodontal ligament (PDL)-bone complex (ATPBC) that simulates clinical crown displacement. An ATPBC was created. It had a socket hosting a tooth with a thin layer of silicon mixture in between for simulating the PDL. The complex was attached to a device that allows applying a controlled force to the crown and measuring the resulting crown displacement. Crown displacements were compared to previously published data for validation. The ATPBC that had a PDL made of two types of silicones, 50% gasket sealant No. 2 and 50% RTV 587 silicone, with a thickness of 0.3 mm, simulated the PDL well. The mechanical behaviors (1) force-displacement relationship, (2) stress relaxation, (3) creep, and (4) hysteresis were validated by the published results. The ATPBC simulated the crown displacement behavior reported from biological studies well.

In Vitro Ligament–Bone Interface Regeneration Using a Trilineage Coculture System on a Hybrid Silk Scaffold

The ligament-bone interface is a complex structure that comprises ligament, fibrocartilage, and bone. We hypothesize that mesenchymal stem cells cocultured in between ligament and bone cells, on a hybrid silk scaffold with sections suitable for each cell type, would differentiate into fibrocartilage. The section of scaffold for osteoblast seeding was coated with hydroxyapatite. A trilineage coculture system (osteoblasts-BMSCs-fibroblasts) on a hybrid silk scaffold was established. RT-PCR results and immunohistochemistry results demonstrated that BMSCs cocultured between fibroblasts and osteoblasts had differentiated into the fibrocartilaginous lineage. The morphological change was also observed by SEM observation. A gradual transition from the uncalcified to the calcified region was formed in the cocultured BMSCs from the region that directly interacted with fibroblasts to the region that directly interacted with osteoblasts. The role of transforming growth factor β3 (TGF-β3) in this trilineage coculture model was also investigated by supplementing the coculture system with 10 ng/mL TGF-β3. The TGF-treated group showed similar results of fibrocartilaginous differentiation of BMSCs with coculture group without TGF-β3 supplement. However, no calcium deposition was found in the cocultured BMSCs in the TGF-treated group. This may indicate TGF-β3 delayed the mineralization process of chondrocytes.

Response of bone marrow stromal cells to graded co-electrospun scaffolds and its implications for engineering the ligament-bone interface

Biomaterial scaffolds with gradients in architecture, mechanical and chemical properties have the potential to improve the osseointegration of ligament grafts by recapitulating phenotypic gradients that exist at the natural ligament-bone (L-B) interface. Towards the larger goal of regenerating the L-B interface, this in vitro study was performed to investigate the potential of two scaffolds with mineral gradients in promoting a spatial gradient of osteoblastic differentiation. Specifically, the first graded scaffold was fabricated by co-electrospinning two polymer solutions (one doped with nano-hydroxyapatite particles) from offset spinnerets, while the second was created by immersing the first scaffold in a 5 × simulated body fluid. Rat bone marrow stromal cells, cultured in the presence of osteogenic supplements, were found to be metabolically active on all regions of both scaffolds after 1 and 7 days of culture. Gene expression of bone morphogenic protein-2 and osteopontin was elevated on mineral-containing regions as compared to regions without mineral, while the expression of alkaline phosphatase mRNA revealed the opposite trend. Finally, the presence of osteopontin and bone sialoprotein confirmed osteoblastic phenotypic maturation by day 28. This study indicates that co-electrospun scaffolds with gradients in mineral content can guide the formation of phenotypic gradients and may thus promote the regeneration of the L-B interface.

Guided tissue regeneration using rigid absorbable membranes in the dog model of chronic furcation defect

Objective. Absorbable membranes are used to promote the regeneration of periodontal defects by Guided Tissue Regeneration (GTR). However, their collapse into the defect is commonly reported, impairing regeneration. Therefore, absorbable but rigid membranes aiming at preventing such collapse were developed and analyzed in periodontal regeneration. Materials and methods. Membranes were analyzed in class II furcation defects in dogs; procedures included periodontal disease induction, prophylaxis and GTR (treated groups) or open flap debridement alone (control group). For GTR, the membranes were made of either 25% hydroxyapatite (HA) in polyhydroxybutyrate matrix (PHB) or 35% HA in PHB. Animals were clinically evaluated for gingival recession, clinical attachment level (CAL) and biopsies were collected at 60 and 120 days. Bone volume, trabeculae number, trabecular thickness and trabecular separation were quantified by micro-computed tomography, followed by histology. Results. Membrane exposure was observed in both treated groups (25 and 35% HAP) from the 8th day after surgery, continuously progressing until 120 days. Mean CAL for all groups remained above normal values for dogs. Bone volumetric values were not significantly different. Partial formation of bone, cementum and periodontal ligament was observed in treated groups. An inflammatory infiltrate was observed in the dense connective tissue that partially filled the center of the treated defects with active osteoclasts on bone surface. Conclusion. Although partial regeneration of the defect was observed, it was limited by wound contamination. Consequently, rigid absorbable membranes made of HA and PHB failed to improve the regeneration of class II furcation defects in dogs.

Anterior cruciate ligament reconstruction in a rabbit model using canine small intestinal submucosa and autologous platelet-rich plasma

BackgroundThe bone–ligament interface is the main point of failure after anterior cruciate ligament reconstruction. Synthetic ligament materials have problems such as a greater failure rate of the bone–ligament insertion than autografts. Small intestinal submucosa (SIS) is a biologic scaffold that has been used to repair musculoskeletal tissue and has been shown to promote cell migration and enhance collagen fiber regeneration. Autologous platelet-rich plasma (PRP) has also been investigated as a potential promoter of tendon healing. We investigated SIS and PRP as biomaterials that might strengthen the bone–tunnel interface and improve tendon structure formation. MethodsAnterior cruciate ligament grafts were formed of braid-twist canine SIS. These canine SIS ligament grafts were used for anterior cruciate ligament reconstruction in 20 New Zealand white rabbits. The rabbits were divided into 2 treatment groups. In 1 group (SIS group; n = 10), we only implanted the canine SIS grafts. In the second group (PRP group; n = 10), we applied autologous PRP to the surgical area after implantation of canine SIS grafts. We determined the cytokine level of the autologous PRP using a transforming growth factor-β1 enzyme-linked immunosorbent assay kit. At 1 and 4 wk after surgery, magnetic resonance imaging was performed to evaluate the grafts. The femur–graft–tibia complex was assessed histologically and biomechanically at 8 wk after surgery. ResultsAt 1 wk after surgery, the magnetic resonance imaging scans of the PRP group showed high signal-intensity lesions. In biomechanical tests, the SIS group had a significantly greater maximum load, maximum stress, and ultimate load and strain than the PRP group. The histologic findings of the PRP group revealed a greater cellular response, fibrotic tissue regeneration around the graft, broad chondrocyte cell infiltration, and collagen fibers that were loosely attached to the bone. ConclusionsThe PRP group had significantly lower tension load values than the SIS group, and there was greater cellular response in a broad area around the grafts of the rabbits in the PRP group compared with those in the SIS group. The early inflammatory responses around the canine SIS grafts in the PRP group and the altered cytokine or growth factor concentration in the intra-articular capsule of the rabbits in PRP group might explain their relatively low tensile strength results.

A comparison of Anterior Cruciate Ligament graft tunnel orientation: Anatomic vs. transtibial

BackgroundRecent Anterior Cruciate Ligament reconstruction techniques have emphasized reproducing the insertion sites of the native Anterior Cruciate Ligament. Anatomic techniques have shown improvements in biomechanical testing, but their superior results have not been shown clinically. The hypothesis of this study is that more oblique tunnels utilized in anatomic reconstructions cause asymmetric loading across the graft. MethodsSeven cadaver knees were tested in a knee simulator that performed a gait cycle and an anterior–posterior laxity test. Each knee underwent both reconstructions in random order utilizing the same Anterior Cruciate Ligament bone patellar tendon bone graft. Before reconstruction, the graft was split longitudinally and miniature force probes were inserted in the medial and lateral portions. FindingsDuring anterior–posterior laxity testing, the transtibial medial bundle averaged 74.8N compared to 87N for the anatomic. The lateral bundles averaged 146.2 and 158N respectively. Both reconstructions exhibited a similar ratio of force distribution between the bundles and there was no statistical difference. The average anterior–posterior motion for the intact knees was 10.8mm compared to 17.0mm after the Anterior Cruciate Ligament was sectioned. Anatomic reconstructions had an average of 14.0mm of laxity compared to 14.9mm for transtibial reconstructions (P<0.038). InterpretationGreater obliquity did not lead to an increase in asymmetry of graft loading. The failure of anatomic reconstructions to show clinical improvement over transtibial reconstructions is not due to oblique tunnels causing asymmetric graft loading.

Therapeutic potential of stem cells in veterinary practice

Stem cell research acquired great attention during last decade inspite of incredible therapeutic potential of these cells the ethical controversies exists. Stem cells have enormous uses in animal cloning, drug discovery, gene targeting, transgenic production and regenerative therapy. Stem cells are the naive cells of body which can self-renew and differentiate into other cell types to carry out multiple functions, these properties have been utilized in therapeutic application of stem cells in human and veterinary medicine. The application of stem cells in human medicine is well established and it is commonly used for chronic and accidental injuries. In Veterinary sciences previous studies mostly focused on establishing protocols for isolation and their characterization but with advancement in array of techniques for in vitro studies, stem cells rapidly became a viable tool for regenerative therapy of chronic, debilitating and various unresponsive clinical diseases and disorders. Multipotent adult stem cells have certain advantages over embryonic stem cells like easy isolation and expansion from numerous sources, less immunogenicity and no risk of teratoma formation hence their use is preferred in therapeutics. Adult stem cells have been utilized for treatment of spinal injuries, tendonitis, cartilage defects, osteoarthritis and ligament defects, liver diseases, wounds, cardiac and bone defects in animals. The multi-potential capability of these cells can be better utilized in near future to overcome the challenges faced by the clinicians. This review will emphasize on the therapeutic utilization and success of stem cell therapies in animals.

Mechanical properties of the avian acrocoracohumeral ligament and its role in shoulder stabilization in flight

Control of movement in the avian shoulder joint is fundamental to understanding the avian wingstroke. The acrocoracohumeral ligament (AHL) is thought to play a key role in stabilizing the glenoid and balancing the pectoralis in gliding flight. If the AHL has to be taut to balance the pectoralis, then it must constrain glenohumeral motion during flapping flight as well. However, birds vary wing kinematics depending on flight speed and behavior. How can a passive ligament accommodate such varying joint movements? Herein, mechanical testing and 3-D modeling are used to link the mechanical properties and morphology of the AHL to its functional role during flapping flight. The bone-ligament-bone complex of the pigeon (Columba livia) fails at a tensile loading of 141 ± 18 N (± s .D., n = 10) or 39 times body weight, which corresponds to a failure stress of 51 MPa, well above expected loads during flight. Simulated AHL length changes, comparisons to glenohumeral kinematics from the literature, and manipulations of partially dissected pigeon specimens all support the hypothesis that the AHL remains taut through downstroke and most of upstroke while becoming slack during the downstroke/upstroke transition. The digital AHL model provides a mechanism for explaining how the AHL can stabilize the shoulder joint under a broad array of humeral paths by constraining the coordination of glenohumeral degrees of freedom.

Three-Dimensional Engineered Bone–Ligament–Bone Constructs for Anterior Cruciate Ligament Replacement

The anterior cruciate ligament (ACL), a major stabilizer of the knee, is commonly injured. Because of its intrinsic poor healing ability, a torn ACL is usually reconstructed by a graft. We developed a multi-phasic, or bone-ligament-bone, tissue-engineered construct for ACL grafts using bone marrow stromal cells and sheep as a model system. After 6 months in vivo, the constructs increased in cross section and exhibited a well-organized microstructure, native bone integration, a functional enthesis, vascularization, innervation, increased collagen content, and structural alignment. The constructs increased in stiffness to 52% of the tangent modulus and 95% of the geometric stiffness of native ACL. The viscoelastic response of the explants was virtually indistinguishable from that of adult ACL. These results suggest that our constructs after implantation can obtain physiologically relevant structural and functional characteristics comparable to those of adult ACL. They present a viable option for ACL replacement.

Premature Osteoblast Clustering by Enamel Matrix Proteins Induces Osteoblast Differentiation through Up-Regulation of Connexin 43 and N-Cadherin

In recent years, enamel matrix derivative (EMD) has garnered much interest in the dental field for its apparent bioactivity that stimulates regeneration of periodontal tissues including periodontal ligament, cementum and alveolar bone. Despite its widespread use, the underlying cellular mechanisms remain unclear and an understanding of its biological interactions could identify new strategies for tissue engineering. Previous in vitro research has demonstrated that EMD promotes premature osteoblast clustering at early time points. The aim of the present study was to evaluate the influence of cell clustering on vital osteoblast cell-cell communication and adhesion molecules, connexin 43 (cx43) and N-cadherin (N-cad) as assessed by immunofluorescence imaging, real-time PCR and Western blot analysis. In addition, differentiation markers of osteoblasts were quantified using alkaline phosphatase, osteocalcin and von Kossa staining. EMD significantly increased the expression of connexin 43 and N-cadherin at early time points ranging from 2 to 5 days. Protein expression was localized to cell membranes when compared to control groups. Alkaline phosphatase activity was also significantly increased on EMD-coated samples at 3, 5 and 7 days post seeding. Interestingly, higher activity was localized to cell cluster regions. There was a 3 fold increase in osteocalcin and bone sialoprotein mRNA levels for osteoblasts cultured on EMD-coated culture dishes. Moreover, EMD significantly increased extracellular mineral deposition in cell clusters as assessed through von Kossa staining at 5, 7, 10 and 14 days post seeding. We conclude that EMD up-regulates the expression of vital osteoblast cell-cell communication and adhesion molecules, which enhances the differentiation and mineralization activity of osteoblasts. These findings provide further support for the clinical evidence that EMD increases the speed and quality of new bone formation in vivo.

Assessing qualitative changes in simulated periodontal ligament and alveolar bone using a non-contact electromagnetic vibration device

The objective of this study is to investigate the ability of a non-contact electromagnetic vibration device to assess a simulated periodontal ligament and alveolar bone conditions in experimental tooth models by applying mechanical parameters (resonant frequency, elastic modulus, and coefficient of viscosity). The non-contact electromagnetic vibration device was made up of three components: vibrator, detector, and analyzer. The experimental tooth model consisted of a cylindrical rod made of polyacetal, a tissue conditioner for soft lining material, and urethane or urethane foam to simulate the tooth, periodontal ligament, and alveolar bone, respectively. The tissue conditioner was prepared by mixing various volumes of liquid with powder. Periotest values (PTVs) were also measured under the same conditions as those of the non-contact electromagnetic vibration device. All of the mechanical parameters derived from the non-contact electromagnetic vibration device significantly decreased as the proportion of liquid increased. Values for the three parameters of the urethane models were significantly larger than those of the urethane foam models. In contrast, PTVs increased significantly as the proportion of liquid increased; however, no significant difference was observed between the urethane and urethane foam models. The non-contact electromagnetic vibration device may be capable of evaluating not only periodontal ligament conditions but also bone quality. Mechanical parameters may be useful for assessing qualitative changes in the periodontal ligament and alveolar bone.