PURPOSE: The aim of this study is to determine whether certain biomaterials have the potential to support cell attachment. After seeding bone marrow stromal cells onto the biomaterials, we investigated their responses to each material in vitro. METHODS: Rat bone marrow derived stromal cells were used. The biomaterials were deproteinized bovine bone mineral (DBBM), DBBM coated with fibronectin (FN), synthetic hydroxyapatite (HA), HA coated with FN, HA coated with beta-tricalcium phosphate (TCP), and pure beta-TCP. With confocal laser scanning microscopy, actin filaments and vinculin were observed after 6, 12, and 24 hours of cell seeding. The morphological features of cells on each biomaterial were observed using scanning electron microscopy at day 1 and 7. RESULTS: The cells on HA/FN and HA spread widely and showed better defined actin cytoskeletons than those on the other biomaterials. At the initial phase, FN seemed to have a favorable effect on cell adhesion. In DBBM, very few cells adhered to the surface. CONCLUSIONS: Within the limitations of this study, we can conclude that in contrast with DBBM not supporting cell attachment, HA provided a more favorable environment with respect to cell attachment.
Actin Cytoskeleton ; Animals ; Biocompatible Materials ; Bone Marrow ; Bone Substitutes ; Calcium Phosphates ; Cell Adhesion ; Durapatite ; Fibronectins ; Mesenchymal Stromal Cells ; Microscopy, Confocal ; Microscopy, Electron, Scanning ; Rats ; Seeds ; Stem Cells ; Stromal Cells ; Transplants ; Vinculin

PURPOSE: The healing process following tooth extraction apparently results in a pronounced resorption of the alveolar ridge. As a result, the width of alveolar ridge is reduced and severe alveolar bone resorption occurs. The purpose of this experiment is to clinically and histologically evaluate the results of using horse-derived bone mineral for socket preservation. METHODS: The study comprised 4 patients who were scheduled for extraction as a consequence of severe chronic periodontitis or apical lesion. The extraction was followed by socket preservation using horse-derived bone minerals. Clinical parameters included buccal-palatal width, mid-buccal crest height, and mid-palatal crest height. A histologic examination was conducted. RESULTS: The surgical sites healed uneventfully. The mean ridge width was 7.75 +/- 2.75 mm at baseline and 7.00 +/- 2.45 mm at 6 months. The ridge width exhibited no significant difference between baseline and 6 months. The mean buccal crest height at baseline was 7.5 +/- 5.20 mm, and at 6 months, 3.50 +/- 0.58 mm. The mean palatal crest height at baseline was 7.75 +/- 3.10 mm, and at 6 months, 5.00 +/- 0.82 mm. There were no significant differences between baseline and 6 months regarding buccal and palatal crest heights. The amount of newly formed bone was 9.88 +/- 2.90%, the amount of graft particles was 42.62 +/- 6.57%, and the amount of soft tissue was 47.50 +/- 9.28%. CONCLUSIONS: Socket preservation using horse-derived bone mineral can effectively maintain ridge dimensions following tooth extraction and can promote new bone formation through osteoconductive activities.
Alveolar Process ; Bone Resorption ; Bone Substitutes ; Chronic Periodontitis ; Humans ; Minerals ; Osteogenesis ; Tooth Extraction ; Tooth Socket ; Transplants

PURPOSE: Fibronectin (FN) has been shown to stimulate bone regeneration in animal models. The aim of this study was to evaluate the capacity of bovine bone mineral coated with synthetic oligopeptides to enhance bone regeneration in rabbit calvarial defects. METHODS: Oligopeptides including fibrin-binding sequences of FN repeats were synthesized on the basis of primary and tertiary human plasma FN structures. Peptide coated and uncoated bone minerals were implanted into 10 mm calvarial defects in New Zealand white rabbits, and the animals were sacrificed at 4 or 8 weeks after surgery. After specimens were prepared, histologic examination and histomorphometric analysis were performed. RESULTS: At 4 weeks after surgery, the uncoated groups showed a limited amount of osteoid formation at the periphery of the defect and the oligopeptide coated groups showed more osteoid formation and new bone formation in the center of the defect as well as at the periphery. At 8 weeks, both sites showed increased new bone formation. However, the difference between the two sites had reduced. CONCLUSIONS: Fibrin-binding synthetic oligopeptide derived from FN on deproteinized bovine bone enhanced new bone formation in rabbit calvarial defects at the early healing stage. This result suggests that these oligopeptides can be beneficial in reconstructing oral and maxillofacial deformities or in regenerating osseous bone defects.
Animals ; Bone Regeneration ; Congenital Abnormalities ; Fibrin ; Fibronectins ; Humans ; Minerals ; Models, Animal ; Oligopeptides ; Osteogenesis ; Plasma ; Rabbits

PURPOSE: The purpose of this study was to compare the bone regeneration effects of cortical, cancellous, and cortico-cancellous human bone substitutes on calvarial defects of rabbits. METHODS: Four 8-mm diameter calvarial defects were created in each of nine New Zealand white rabbits. Freeze-dried cortical bone, freeze-dried cortico-cancellous bone, and demineralized bone matrix with freeze-dried cancellous bone were inserted into the defects, while the non-grafted defect was regarded as the control. After 4, 8, and 12 weeks of healing, the experimental animals were euthanized for specimen preparation. Micro-computed tomography (micro-CT) was performed to calculate the percent bone volume. After histological evaluation, histomorphometric analysis was performed to quantify new bone formation. RESULTS: In micro-CT evaluation, freeze-dried cortico-cancellous human bone showed the highest percent bone volume value among the experimental groups at week 4. At week 8 and week 12, freeze-dried cortical human bone showed the highest percent bone volume value among the experimental groups. In histologic evaluation, at week 4, freeze-dried cortico-cancellous human bone showed more prominent osteoid tissue than any other group. New bone formation was increased in all of the experimental groups at week 8 and 12. Histomorphometric data showed that freeze-dried cortico-cancellous human bone showed a significantly higher new bone formation percentile value than any other experimental group at week 4. At week 8, freeze-dried cortical human bone showed the highest value, of which a significant difference existed between freeze-dried cortical human bone and demineralized bone matrix with freeze-dried cancellous human bone. At week 12, there were no significant differences among the experimental groups. CONCLUSIONS: Freeze-dried cortico-cancellous human bone showed swift new bone formation at the 4-week healing phase, whereas there was less difference in new bone formation among the experimental groups in the following healing phases.
Animals ; Bone Matrix ; Bone Regeneration ; Bone Substitutes ; Humans ; Osteogenesis ; Rabbits ; X-Ray Microtomography

PURPOSE: It has been reported that low-level semiconductor diode lasers could enhance the wound healing process. The periodontal ligament is crucial for maintaining the tooth and surrounding tissues in periodontal wound healing. While low-level semiconductor diode lasers have been used in low-level laser therapy, there have been few reports on their effects on periodontal ligament fibroblasts (PDLFs). We performed this study to investigate the biological effects of semiconductor diode lasers on human PDLFs. METHODS: Human PDLFs were cultured and irradiated with a gallium-aluminum-arsenate (GaAlAs) semiconductor diode laser of which the wavelength was 810 nm. The power output was fixed at 500 mW in the continuous wave mode with various energy fluencies, which were 1.97, 3.94, and 5.91 J/cm2. A culture of PDLFs without laser irradiation was regarded as a control. Then, cells were additionally incubated in 72 hours for MTS assay and an alkaline phosphatase (ALPase) activity test. At 48 hours post-laser irradiation, western blot analysis was performed to determine extracellular signal-regulated kinase (ERK) activity. ANOVA was used to assess the significance level of the differences among groups (P<0.05). RESULTS: At all energy fluencies of laser irradiation, PDLFs proliferation gradually increased for 72 hours without any significant differences compared with the control over the entire period taken together. However, an increment of cell proliferation significantly greater than in the control occurred between 24 and 48 hours at laser irradiation settings of 1.97 and 3.94 J/cm2 (P<0.05). The highest ALPase activity was found at 48 and 72 hours post-laser irradiation with 3.94 J/cm2 energy fluency (P<0.05). The phosphorylated ERK level was more prominent at 3.94 J/cm2 energy fluency than in the control. CONCLUSIONS: The present study demonstrated that the GaAlAs semiconductor diode laser promoted proliferation and differentiation of human PDLFs.
Alkaline Phosphatase ; Blotting, Western ; Cell Proliferation ; Extracellular Signal-Regulated MAP Kinases ; Fibroblasts ; Humans ; Low-Level Light Therapy ; Lasers, Semiconductor ; Periodontal Ligament ; Phosphotransferases ; Semiconductors ; Tooth ; Wound Healing

PURPOSE: To prolong the degradation time of collagen membranes, various cross-linking techniques have been developed. For cross-linking, chemicals such as formaldehyde and glutaraldehyde are added to collagen membranes, but these chemicals could adversely affect surrounding tissues. The aim of this study is to evaluate the ability of porous non-chemical cross-linking porcine-derived collagen nanofibrous membrane to enhance bone and associated tissue regeneration in one-wall intrabony defects in beagle dogs. METHODS: The second and third mandibular premolars and the first molars of 2 adult beagles were extracted bilaterally and the extraction sites were allowed to heal for 10 weeks. One-wall intrabony defects were prepared bilaterally on the mesial and distal side of the fourth mandibular premolars. Among eight defects, four defects were not covered with membrane as controls and the other four defects were covered with membrane as the experimental group. The animals were sacrificed 10 weeks after surgery. RESULTS: Wound healing was generally uneventful. For all parameters evaluating bone regeneration, the experimental group showed significantly superior results compared to the control. In new bone height (NBh), the experimental group exhibited a greater mean value than the control (3.04 +/- 0.23 mm/1.57 +/- 0.59, P = 0.003). Also, in new bone area (NBa) and new bone volume (NBv), the experimental group showed superior results compared to the control (NBa, 34.48 +/- 10.21% vs. 5.09 +/- 5.76%, P = 0.014; and NBv, 28.04 +/- 12.96 vs. 1.55 +/- 0.57, P = 0.041). On the other hand, for parameters evaluating periodontal tissue regeneration, including junctional epithelium migration and new cementum height, there were no statistically significant differences between two groups. CONCLUSIONS: Within the limitations of this study, this collagen membrane enhanced bone regeneration at one-wall intrabony defects. On the other hand, no influence of this membrane on periodontal tissue regeneration could be ascertained in this study.
Absorbable Implants ; Adult ; Animals ; Bicuspid ; Bone Regeneration ; Collagen ; Dental Cementum ; Dogs ; Epithelial Attachment ; Formaldehyde ; Glutaral ; Guided Tissue Regeneration ; Hand ; Humans ; Membranes ; Molar ; Regeneration ; Wound Healing

PURPOSE: The aim of this study was to investigate the immunomodulatory effects of canine periodontal ligament stem cells on allogenic and xenogenic immune cells in vitro. METHODS: Mixed cell cultures consisting of canine stem cells (periodontal ligament stem cells and bone marrow stem cells) and allogenic canine/xenogenic human peripheral blood mononuclear cells (PBMCs) were established following the addition of phytohemagglutinin. The proliferation of PBMCs was evaluated using the MTS assay. The cell division of PBMCs was analyzed using the CFSE assay. The apoptosis of PBMCs was assessed using the trypan blue uptake method. RESULTS: Periodontal ligament stem cells and bone marrow stem cells inhibited the proliferation of allogenic and xenogenic PBMCs. Both periodontal ligament stem cells and bone marrow stem cells suppressed the cell division of PBMCs despite the existence of a mitogen. No significant differences in the percentages of apoptotic PBMCs were found among the groups. CONCLUSIONS: Canine periodontal ligament stem cells have an immunomodulatory effect on allogenic and xenogenic PBMCs. This effect is not a product of apoptosis of PBMCs but is caused by the inhibition of cell division of PBMCs.
Apoptosis ; Bone Marrow ; Cell Culture Techniques ; Cell Division ; Diminazene ; Fluoresceins ; Humans ; Immunomodulation ; Ligaments ; Periodontal Ligament ; Stem Cells ; Succinimides ; Trypan Blue

PURPOSE: The aim of this study was to compare the effectiveness of hydroxyapatite containing toothpaste with positive control toothpastes in reducing dentine hypersensitivity. MATERIALS AND METHODS: This clinical trial was a double-blind, randomized, parallel group comparison of two, namely hydroxyapatite containing toothpaste and strontium chloride containing toothpaste. A total of 55 subjects were included in this study. The subjects were given randomly assigned one of the two toothpastes after received tooth brushing instruction at baseline. Some clinical indices(PI, GI, PD), verbal rating score(VRS) for sensitivity to stimulus, the effect in relieving sensitivity and visual analogue scale(VAS) for sensitivity at baseline, week 2, week 4 and week 8 were assessed. All data were evaluated by intention-to-treat analysis. RESULTS: Overall, PI and GI scores were significantly reduced compare baseline in all groups(p<0.05). In addition, there was significant difference in PI at 4 weeks and in GI at 4, 8 weeks between groups. The proportions of subjects relieved sensitivity were 70.4% in experimental group and 57.1% in control group at 8 weeks respectively. The VRS for sensitivity to three kinds of stimuli and VAS for sensitivity decreased according to time, there was no overall difference between two groups(p>0.05). CONCLUSION: This study demonstrated that the new hydroxyapatite containing toothpaste was similarly effective in reducing dentine hypersensitivity with pre-existing benchmark toothpaste.
Dentin ; Dentin Sensitivity ; Durapatite ; Strontium ; Tooth ; Toothpastes

PURPOSE: Fibronectin(FN), one of the major components of ECM, mediates wide variety of cellular interactions including cell adhesion, migration, proliferation and differentiation. In this study, we used synthetic peptides based on fibrin binding sites of amino-terminal of FN and evaluated their biologic effects on periodontal ligament(PDL) cells. MATERIALS AND METHODS: PDL cells were cultured on synthetic oligopeptides coated dishes and examined for cell adhesion, proliferation via confocal microscope. For detection of ERK1/2, cells were plated and Western blot analysis was performed. RESULTS: PDL cells on synthetic oligopeptide coated dishes showed enhanced cell adhesion and proliferation. Western blot analysis revealed increased level of ERK1/2 phosphorylation in cells plated on FN fragment containing fibrin-binding domain(FF1 and FF5) coated dishes. CONCLUSION: These results reveals that FN fragment containing fibrin-binding domain possess an enhanced biologic effect of PDL ligament cells.
Binding Sites ; Blotting, Western ; Cell Adhesion ; Fibrin ; Fibronectins ; Ligaments ; Oligopeptides ; Peptides ; Periodontal Ligament ; Phosphorylation

PURPOSE: The aim of this study was to evaluate the stemness of cells from canine dental tissues and bone marrow. METHODS:Canine periodontal ligament stem cells (PDLSC), alveolar bone stem cells (ABSC) and bone marrow stem cells(BMSC) were isolated and cultured. Cell differentiations (osteogenic, adipogenic and chondrogenic) and surface antigens (CD146, STRO-1, CD44, CD90, CD45, CD34) were evaluated in vitro. The cells were transplanted into the subcutaneous space of nude mice to assess capacity for ectopic bone formation at 8 weeks after implantation. RESULTS: PDLSC, ABSC and BMSC differentiated into osteoblasts, adipocytes and chondrocytes under defined condition. The cells expressed the mesenchymal stem cell markers differently. When transplanted into athymic nude mice, these three kinds of cells with hydroxyapatite /beta tricalcium phosphate (HA/TCP) carrier showed ectopic bone formation. CONCLUSIONS: This study demonstrated that canine dental stem cells have stemness like bone marrow stem cells. Transplantation of these cells might be used as a therapeutic approach for dental stem cell-mediated periodontal tissue regeneration.
Adipocytes ; Animals ; Antigens, Surface ; Bone Marrow ; Calcium Phosphates ; Cell Differentiation ; Chondrocytes ; Durapatite ; Mesenchymal Stromal Cells ; Mice ; Mice, Nude ; Osteoblasts ; Osteogenesis ; Periodontal Ligament ; Regeneration ; Stem Cells ; Transplants