Effects of Sapindus mukorossi Seed Oil on Bone Healing Efficiency: An Animal Study.

Natural products have attracted great interest in the development of tissue engineering. Recent studies have demonstrated that unsaturated fatty acids found in natural plant seed oil may exhibit positive osteogenic effects; however, few in vivo studies have focused on the use of plant seed oil for bone regeneration. The aim of this study is to investigate the effects of seed oil found in Sapindus mukorossi (S. mukorossi) on the osteogenic differentiation of mesenchymal stem cells and bone growth in artificial bone defects in vivo. In this study, Wharton-jelly-derived mesenchymal stem cells (WJMSCs) were co-cultured with S. mukorossi seed oil. Cellular osteogenic capacity was assessed using Alizarin Red S staining. Real-time PCR was carried out to evaluate ALP and OCN gene expression. The potential of S. mukorossi seed oil to enhance bone growth was assessed using an animal model. Four 6 mm circular defects were prepared at the parietal bone of New Zealand white rabbits. The defects were filled with hydrogel and hydrogel-S. mukorossi seed oil, respectively. Quantitative analysis of micro-computed tomography (Micro-CT) and histological images was conducted to compare differences in osteogenesis between oil-treated and untreated samples. Although our results showed no significant differences in viability between WJMSCs treated with and without S. mukorossi seed oil, under osteogenic conditions, S. mukorossi seed oil facilitated an increase in mineralized nodule secretion and upregulated the expression of ALP and OCN genes in the cells (p < 0.05). In the animal study, both micro-CT and histological evaluations revealed that new bone formation in artificial bone defects treated with S. mukorossi seed oil were nearly doubled compared to control defects (p < 0.05) after 4 weeks of healing. Based on these findings, it is reasonable to suggest that S. mukorossi seed oil holds promise as a potential candidate for enhancing bone healing efficiency in bone tissue engineering.

Antioxidants protect against gingival overgrowth induced by cyclosporine A.

OBJECTIVE: We investigated the importance of reactive oxygen species (ROS) on developing gingival overgrowth (GO) and then introduced the antioxidant strategy to prevent, or even reduce GO. BACKGROUND: Gingival overgrowth is a common side effect of the patients receiving cyclosporine A (CsA), an immune suppressant. Although it has been broadly investigated, the exact pathogenesis of the induced GO is still uncertain. METHODS: We cultured human primary gingival fibroblasts and used animal model of GO to investigate the ameliorative effects of antioxidants on CsA-induced GO. To examine the CsA-induced oxidative stress, associated genes and protein expression, and the overgrown gingiva of rats by using immunocytochemistry, confocal laser scanning microscopy, real-time PCR, ELISA, gelatin zymography, gingival morphological, and immunohistochemical analysis. RESULTS: We found for the first time that ROS was responsible for the CsA-induced oxidative stress and TGF-ß1 expression in human primary gingival fibroblasts, as well as the GO of rats. The antioxidants (oxidative scavenger of vitamin E and an antioxidative enzyme inducer of hemin) ameliorated CsA-induced pathological and morphological alterations of GO without affected the CsA-suppressed il-2 expression in rats. CsA-induced oxidative stress, HO-1, TGF-ß1, and type II EMT were also rescued by antioxidants treatment. CONCLUSIONS: We concluded that CsA repetitively stimulating the production of ROS is the cause of CsA-GO which is ameliorated by treating antioxidants, including vitamin E and sulforaphane. Furthermore, the immunosuppressive effect of CsA is not interfered by antioxidant treatments in rats. This finding may thus help the clinician devise better prevention strategies in patients susceptible to GO.

Recommendations for treating stage I-III periodontitis in the Taiwanese population: A consensus report from the Taiwan Academy of Periodontology.

BACKGROUND/PURPOSE: Based on the fundamental of the S3-level clinical practice guideline (CPG) for treating stage I-III periodontitis developed by the European Federation of Periodontology (EFP), this consensus report aimed to develop treatment recommendations for treating periodontitis in the Taiwanese population. METHODS: The report was constructed by experts from the Taiwan Academy of Periodontology. The following topics were reviewed: (a) the prevalence of periodontitis in Asia and current status of treatment in Taiwan; (b) specific anatomical considerations for treating periodontitis in Asians; (d) educational and preventive interventions and supragingival plaque control; (d) subgingival instrumentation and adjunctive treatment; (e) surgical periodontal therapy; and (f) maintenance and supportive periodontal care. Recommendations were made according to the evidences from the EFP CPG, the published literature and clinical studies in Asians, and the expert opinions. RESULTS: The treatment recommendations for the Taiwanese population were generally in parallel with the EFP CPG, and extra cautions during treatment and maintenance phases were advised due to the anatomical variations, such as shorter root trunk, higher prevalence of supernumerary distolingual root and lingual bony concavity in mandibular posteriors, and thinner anterior labial plate, of the Asian population. CONCLUSION: The EFP CPG could be adopted for treating periodontitis and maintaining periodontal health of the Taiwanese population, and anatomical variations should be cautious when the treatment is delivered.

Assessment of the changes in retention and surface topography of attachments for maxillary 4-implant-retained overdentures.

STATEMENT OF PROBLEM: Restoring the edentulous maxilla with an implant-retained overdenture (IRO) can present a challenge because of increased implant divergence and the added wear of the implant abutments and attachments. However, knowledge pertaining to the degree of implant divergence and its effects on the wear pattern of the implant attachments is lacking. PURPOSE: The purpose of this in vitro study was to investigate the change in the retention and wear characteristics of unsplinted abutments and attachments when used to retain a maxillary 4-implant palateless complete removable overdenture with different implant angulations. MATERIAL AND METHODS: Three groups of specimens of 0-, 15-, and 30-degree implant angulations were evaluated, each with 7 specimens. The retention of specimens was recorded after aging cycles equivalent to 1, 2.5, and 6 years of use. The surface of the attachments was examined with light and scanning electron microscope (SEM). RESULTS: Increasing the interimplant divergence improved the initial retention. After 1 year of use, retention of the 15- and 30-degree groups was significantly higher than that of the 0-degree group (P<.05). No significant difference in retention was found between the 15- and 30-degree groups (P>.05). After 2.5 and 6 years of use, no significant difference in retention was noted between groups (P>.05). Under light and SEM examination, the wear of the abutments and attachments was related to the interimplant divergence. CONCLUSIONS: The initial retention of single attachments increased significantly as the implant divergence increased. The retention of the 15- and 30-degree groups was significantly higher than that of the 0-degree group after 1 year of use. No significant difference in retention was found after 2.5 and 6 years, regardless of implant angulation.

Fibroblast-enhanced cyclophilin A releasing from U937 cell upregulates MMP-2 in gingival fibroblast.

OBJECTIVE: This in vitro study aimed to evaluate the expression of cyclophilin A (CyPA) in U937 monocytic cells after coculturing with the human gingival fibroblasts (HGFs) and the effect of CyPA on the augmentation of MMP-2 expression in the coculture environment. BACKGROUND: Leukocyte infiltration in gingival connective tissue is one of the major findings in the lesions of inflammatory periodontal diseases. A crosstalk between the resident gingival fibroblasts and the recruited inflammatory cells that promote the expression of matrix metalloproteinases (MMPs) was proposed based on recent findings, whereas the cluster of differentiation 147 (CD147)-CyPA pathway was suggested to be involved with the crosstalk. MATERIAL AND METHODS: CyPA was released into media, in the independent or transwell coculture of HGF and U937 cells, as determined by enzyme-linked immunosorbent assay, whereas intracellular mRNA expressions for CyPA and MMP-2 were examined by quantitative real-time polymerase chain reaction, in the transwell coculture or conditional medium models. Zymography was conducted to analyze the activities of pro-MMP-2/MMP-2 released into the media. RESULTS: (a) A significantly increased CyPA protein level was observed in the transwell coculture media compared with that in the independent culture. (b) The transwell coculture-enhanced mRNA expression for CyPA was noticed in U937 cells but not in HGFs. After adding with HGF-conditioned medium, the mRNA enhancement in U937 cells occurred in a dose-dependent manner. (c) Although the MMP-2 activities significantly increased after transwell coculturing, the MMP-2 mRNA enhancement was observed only in HGFs. (d) Exogenous CyPA could enhance MMP-2 activities in HGFs in a dose-dependent manner. However, the CyPA antagonist reduced the MMP-2 activities in the transwell cocultures. (e) Moreover, the CyPA-enhanced MMP-2 activity in HGF was decreased significantly by the pathway inhibitor for c-Jun amino-terminal kinase (JNK). CONCLUSION: Based on the present findings, we suggest that gingival fibroblasts could enhance the CyPA release from U937 cells, via the JNK pathway, resulting in MMP-2 enhancement in fibroblasts. The finding shed light on a new mechanism of cellular interaction involving MMP-2 and CyPA, in two cells.

2,3,5,4'-Tetrahydroxystilbene-2-O-ß-glucoside Isolated from Polygoni Multiflori Ameliorates the Development of Periodontitis.

Periodontitis, a chronic infection by periodontopathic bacteria, induces uncontrolled inflammation, which leads to periodontal tissue destruction. 2,3,5,4'-Tetrahydroxystilbene-2-O-beta-glucoside (THSG), a polyphenol extracted from Polygoni Multiflori, reportedly has anti-inflammatory properties. In this study, we investigated the mechanisms of THSG on the Porphyromonas gingivalis-induced inflammatory responses in human gingival fibroblasts and animal modeling of ligature-induced periodontitis. Human gingival fibroblast cells were treated with lipopolysaccharide (LPS) extracted from P. gingivalis in the presence of resveratrol or THSG to analyze the expression of TNF-α, IL-1ß, and IL-6 genes. Increased AMP-activated protein kinase (AMPK) activation and SirT1 expression were induced by THSG. Treatment of THSG decreased the expression of LPS-induced inflammatory cytokines, enhanced AMPK activation, and increased the expression of SirT1. In addition, it suppressed the activation of NF-κB when cells were stimulated with P. gingivalis LPS. The anti-inflammatory effect of THSG and P. Multiflori crude extracts was reproduced in ligature-induced periodontitis animal modeling. In conclusion, THSG inhibited the inflammatory responses of P. gingivalis-stimulated human gingival fibroblasts and ameliorated ligature-induced periodontitis in animal model.

A Novel Application of 3D Printing Technology Facilitating Shell Wound Healing of Freshwater Turtle.

Numerous cases and a shortage of resources usually limit wild animal rescue. New technology might save these severely injured wild animals from euthanasia by easing the requirement of intensive medication. Three-dimensional (3D) technologies provide precise and accurate results that improve the quality of medical applications. These 3D tools have become relatively low-cost and accessible in recent years. In the medical field of exotic animals, turtle shell defects are highly challenging because of inevitable water immersion. This report is the first attempt to apply the combination of 3D scanning, computer-aided design (CAD), and 3D printing to make a device that protects the wound from exposure to water or infection sources. The presented techniques successfully extricate a wild freshwater turtle from an extensive shell defect within a short period. Integration of multiple sciences to 3D technology can provide a facile model for veterinary medical applications.

A novel application of dynamic guided navigation system in immediate implant placement.

BACKGROUND/PURPOSE: Immediate placement in the esthetic zone has been a predictable treatment option. However, it requires the clinician to be experienced and knowledgeable about esthetic diagnosis, accurate 3-dimensional (3D) implant placement, and restoratively driven planning/placement. Therefore, this study aimed to investigate a novel workflow integrating dynamic navigation to immediate single-implant placement in the aesthetic zone. MATERIALS AND METHODS: We included ten patients who required at least one implant in the esthetic area and were treated with post-extraction socket implant placement. Osteotomy and implant placement followed computer-assisted implant positioning and image-guided dynamic navigation. Treatment outcomes were implant success rates, surgical and prosthetic complications, marginal bone level (MBL), modified pink esthetic score, and white score. RESULTS: In the consecutive clinical cases, patients were satisfied with implant therapy's function and esthetic outcome in the esthetic zone. No other surgical or biological complications occurred, which accounts for the 100% cumulative success rate. The mean MBL was -0.76 ± 0.15 mm assessed using standardized intraoral digital periapical radiographs. CONCLUSION: The novel application of a dynamic guided navigation system is a dependable clinical protocol to obtain optimal implant position/angulation and esthetics on immediate implant placement.

Porphyromonas gingivalis lipopolysaccharide and gingival fibroblast augment MMP-9 expression of monocytic U937 cells through cyclophilin A.

BACKGROUND: Intercellular cross-talking was suggested in matrix metalloproteinase (MMP)-9 expression with unknown mechanisms. Studies showed cyclophilin A (CypA) playing an important role in regulating MMP-9 expression in varied diseases. The aim of the study was to examine the CyPA on the MMP-9 augmentation in monocytic U937 cells after Porphyromonas gingivalis (Pg) lipopolysaccharide (LPS) treatment and human gingival fibroblast (hGF) co-culture. METHODS: In independent culture or co-culture of hGF and U937 cell, quantitative real-time polymerase chain reaction (qPCR) and zymography were selected to examine the mRNA and protein activity of MMP-9, respectively. The CyPA expression was determined by qPCR. RESULTS: LPS could enhance MMP-9 mRNA expression and enzyme activity in U937 cell. However, the enhancements were not observed in hGF. Similarly, LPS enhanced CyPA mRNA in U937, but not in hGF. After co-cultured with hGF, however, MMP-9 and CyPA in U937 increased regardless of the presence/absence of LPS. In U937 cells, the extra-supplied CyPA increased MMP-9 mRNA and enzyme activity, whereas the CyPA inhibitor, cyclosporine A, suppressed the LPS- and co-culture-enhanced MMP-9. Moreover, the inhibitors for MAP kinase, including PD98059 (ERK) and SP600125 (JNK), suppressed the CyPA-enhanced MMP-9 in U937. CONCLUSION: Through the CyPA pathway, the LPS and the hGF could augment the MMP-9 expression in the U937 cells.

Comparison of 2,3,5,4'-tetrahydroxystilbene-2-O-b-D-glucoside-induced proliferation and differentiation of dental pulp stem cells in 2D and 3D culture systems-gene analysis.

BACKGROUND/PURPOSE: Culture environments play a critical role in stem cell expansion. This study aimed to evaluate the effects of 2,3,5,4'-tetrahydroxystilbene-2-O-b-D-glucoside (THSG) on the proliferation and differentiation of human dental pulp stem cells (DPSCs) in 2-dimensional (2D) and 3-dimensional (3D) culture systems. MATERIALS AND METHODS: Human DPSCs were seeded in T25 flasks for 2D cultivation. For the 3D culture system, DPSCs were mixed with microcarriers and cultured in spinner flasks. Cells in both culture systems were treated with THSG, and cell proliferation was determined using a cell counter and a 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-tetrazolium bromide assay. In THSG-treated DPSCs, the genes associated with proliferation, adipogenesis, neurogenesis, osteogenesis, pluripotency, oncogenesis, and apoptosis were analyzed using real-time polymerase chain reactions. RESULTS: The spinner flask time-dependently improved cell numbers, cell viability, and expansion rates in THSG-treated DPSCs. In both the T25 and spinner flasks, the messenger RNA (mRNA) levels of proliferation, osteogenesis, and pluripotent-related genes had a significant maximum expression with 10 µM THSG treatment. However, 0.1 µM of THSG may be the most suitable condition for triggering neurogenesis and adipogenesis gene expression when DPSCs were cultured in spinner flasks. Furthermore, the number of oncogenes and apoptotic genes decreased considerably in the presence of THSG in both the T25 and spinner flasks. CONCLUSION: The spinner flask bioreactor combined with THSG may upregulate proliferation and lineage-specific differentiation in DPSCs. Thus, the combination can be used to mass-produce and cultivate human DPSCs for regenerative dentistry.

Fabrication of Low-Molecular-Weight Hyaluronic Acid-Carboxymethyl Cellulose Hybrid to Promote Bone Growth in Guided Bone Regeneration Surgery: An Animal Study.

Guided bone regeneration surgery is an important dental operation used to regenerate enough bone to successfully heal dental implants. When this technique is performed on maxilla sinuses, hyaluronic acid (HLA) can be used as an auxiliary material to improve the graft material handling properties. Recent studies have indicated that low-molecular hyaluronic acid (L-HLA) provides a better regeneration ability than high-molecular-weight (H-HLA) analogues. The aim of this study was to fabricate an L-HLA-carboxymethyl cellulose (CMC) hybrid to promote bone regeneration while maintaining viscosity. The proliferation effect of fabricated L-HLA was tested using dental pulp stem cells (DPSCs). The mitogen-activated protein kinase (MAPK) pathway was examined using cells cultured with L-HLA combined with extracellular-signal-regulated kinase (ERK), c-Jun N-terminal kinase (JNK), and p38 inhibitors. The bone growth promotion of fabricated L-HLA/CMC hybrids was tested using an animal model. Micro-computer tomography (Micro-CT) and histological images were evaluated quantitatively to compare the differences in the osteogenesis between the H-HLA and L-HLA. Our results show that the fabricated L-HLA can bind to CD44 on the DPSC cell membranes and affect MAPK pathways, resulting in a prompt proliferation rate increase. Micro CT images show that new bone formation in rabbit calvaria defects treated with L-HLA/CMC was almost two times higher than in defects filled with H-HLA/CMC (p < 0.05) at 4 weeks, a trend that remained at 8 weeks and was confirmed by HE-stained images. According to these findings, it is reasonable to conclude that L-HLA provides better bone healing than H-HLA, and that the L-HLA/CMC fabricated in this study is a potential candidate for improving bone healing efficiency when a guided bone regeneration surgery was performed.

Bone formation with functionalized 3D printed poly-ε-caprolactone scaffold with plasma-rich-fibrin implanted in critical-sized calvaria defect of rat.

BACKGROUND/PURPOSE: Space-making is one of the essential factors for bone regeneration in severe bony defect. To test the hypothesis that an appropriately designed scaffold may be beneficial for the bone formation in defect, the new bone formed in the critical-size calvarial defect of rat was examined after implanted with a 3D-printed poly-ɛ-caprolactone (PCL) scaffold, retaining with and without plasma rich fibrin (PRF). MATERIALS AND METHODS: Thirty-two rats were divided into four groups (control, PCL, PRF, and PCL-plus-PRF). A custom-made 3D-printed PCL scaffold, 900 µm in pore size, retaining with and without PRF, was implanted into a critical-sized calvarial defect, 6 mm in diameter. Animals were sacrificed at week-4 or 8 after implantation for assessing the new bone formation by dental radiography, micro-computed tomography (µ-CT), and histology. RESULTS: By radiography and µ-CT, significantly greater mineralization areas/volumes were observed in defects with 3D-printed scaffold groups compared to that without the scaffold in both two-time points. However, no advantage was found by adding PRF. Histology showed that bone tissues grew into the central zone of the critical defect when 3D-printed PCL scaffold was present. In contrast, for the groups without the scaffolds, new bones were formed mostly along defect borders, and the central zones of the defects were collapsed and healed with thin connective tissue. CONCLUSION: Our results suggest that the use of a 900 µm pore size 3D-printed PCL scaffold may have the potential in facilitating the new bone formation.

Estimation of the Effect of Accelerating New Bone Formation of High and Low Molecular Weight Hyaluronic Acid Hybrid: An Animal Study.

Osteoconduction is an important consideration for fabricating bio-active materials for bone regeneration. For years, hydroxyapatite and ß-calcium triphosphate (ß-TCP) have been used to develop bone grafts for treating bone defects. However, this material can be difficult to handle due to filling material sagging. High molecular weight hyaluronic acid (H-HA) can be used as a carrier to address this problem and improve operability. However, the effect of H-HA on bone formation is still controversial. In this study, low molecular weight hyaluronic acid (L-HA) was fabricated using gamma-ray irradiation. The viscoelastic properties and chemical structure of the fabricated hybrids were evaluated by a rheological analysis nuclear magnetic resonance (NMR) spectrum. The L-MH was mixed with H-HA to produce H-HA/L-HA hybrids at ratios of 80:20, 50:50 and 20:80 (w/w). These HA hybrids were then combined with hydroxyapatite and ß-TCP to create a novel bone graft composite. For animal study, artificial bone defects were prepared in rabbit femurs. After 12 weeks of healing, the rabbits were scarified, and the healing statuses were observed and evaluated through micro-computer tomography (CT) and tissue histological images. Our viscoelastic analysis showed that an HA hybrid consisting 20% H-HA is sufficient to maintain elasticity; however, the addition of L-HA dramatically decreases the dynamic viscosity of the HA hybrid. Micro-CT images showed that the new bone formations in the rabbit femur defect model treated with 50% and 80% L-HA were 1.47 (p < 0.05) and 2.26 (p < 0.01) times higher than samples filled with HA free bone graft. In addition, a similar tendency was observed in the results of HE staining. These results lead us to suggest that the material with an H-HA/L-HA ratio of 50:50 exhibited acceptable viscosity and significant new bone formation. Thus, it is reasonable to suggest that it may be a potential candidate to serve as a supporting system for improving the operability of granular bone grafts and enhancing new bone formations.

2,3,5,4'-tetrahydroxystilbene-2-O-b-D-glucoside triggers the pluripotent-like possibility of dental pulp stem cells by activating the JAK2/STAT3 axis: Preliminary observations.

Abstract. BACKGROUND/PURPOSE: Although 2,3,5,4'-Tetrahydroxystilbene-2-O-beta-glucoside (THSG) reportedly has anti-inflammatory properties, its role in inducing the dedifferentiation of human dental pulp stem cells (DPSC) into pluripotent-like stem cells remains to be determined. The purpose of this study is to evaluate the effects of THSG on the pluripotent-like possibility and mechanism of DPSC. MATERIALS AND METHODS: DPSCs were treated with THSG, and cell viability was determined using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-tetrazolium bromide (MTS) assay. Real-time polymerase chain reaction was used to analyze the mRNA expression levels of pluripotency-associated genes and oncogenes and to detect telomerase activity in the cells. Embryoid body formation assay was conducted, and pluripotency-related proteins were identified using Western blotting. Data were analyzed using one-way analysis of variance. RESULTS: Cell viability, telomerase activity, and embryoid body formation were enhanced in THSG-treated DPSCs. The mRNA expression levels of pluripotent-like genes (including Nanog homeobox [NANOG], SRY-box 2 [SOX2], and POU class 5 homeobox 1 [POU5F1/OCT4]) significantly increased after THSG treatment. The expression levels of pluripotency-related genes (Janus kinase-signal transducer 2 [JAK2] and signal transducer and activator of transcription 3 [STAT3]) increased, whereas those of oncogenes (Ras, SRC, HER2, and C-sis) decreased. Furthermore, the expression levels of the phosphorylated JAK2 and STAT3 proteins significantly increased after THSG treatment. CONCLUSION: THSG treatment may enhance the pluripotent-like possibility of DPSC through the JAK2/STAT3 axis. Hence, it may be used as an alternative cell-based therapeutic strategy in regenerative dentistry.

2,3,5,4'-Tetrahydroxystilbene-2-O-ß-d-glucoside promotes the effects of dental pulp stem cells on rebuilding periodontal tissues in experimental periodontal defects.

BACKGROUND: This study aimed to investigate the regenerative effects of 2,3,5,4'-tetrahydroxystilbene-2-O-ß-d-glucoside (THSG)-treated human dental pulp stem cells (DPSC) on the healing of experimental periodontal defects in rats. METHODS: The maxillary first molars of 30 male Sprague-Dawley rats were extracted, and after healing, bilateral periodontal defects were surgically created mesially in second molars. The defects were treated with Matrigel (as control), DPSC, or DPSC + THSG. After 2 weeks, the healed defects were evaluated using microcomputed tomography and through histological and immunohistochemical analyses. RESULTS: In the microcomputed tomography analysis, more new bone formation in the DPSC and DPSC + THSG groups was observed compared with the control group. The periodontal bone supporting ratio in site with DPSC + THSG was significantly higher than that in DPSC. Histologically, an enhanced new bone formation and more significant periodontal attachment were observed in the DPSC + THSG group. The expression levels of proliferating cell nuclear antigen (PCNA), vascular endothelial growth factor (VEGF), and osteopontin (OPN) in the DPSC + THSG group were significantly greater than those in other groups. CONCLUSIONS: THSG-revolutionized DPSCs significantly shortened the regenerative period of periodontal defects by enhancing the cell recruitment and possibly the angiogenesis in rat models, which illustrate the critical implications for a clinical application and provide a novel tactic for periodontitis treatment.

A novel design of palatal stent to reduce donor site morbidity in periodontal plastic surgery.

BACKGROUND/ PURPOSE: The connective tissue graft from hard palate is a reliable graft technique that has been used for achieving root coverage, increasing keratinized tissue width and thickness in periodontal plastic surgeries. Donor site morbidities, including complications from postoperative bleeding, pain during healing phase, difficulties in eating and speaking and unexpecting healing patterns, are always a concern for both doctors and patients. The aim of this study was to investigate a novel design of palatal stent to reduce these complications and provide patient with a smooth healing experience after soft tissue harvesting from hard palate. MATERIALS AND METHODS: Eight patients requiring connective tissue graft from palatal site were included in the study. The palatal stents made with light-curing hybrid composite resin were fabricated and tried in for patients prior to the periodontal plastic surgeries. Stent was delivered immediately without other dressing material or suture after the graft harvesting procedure for blood clot stabilization. Bleeding tendency was evaluated at the completion of the procedure. Patients came back for follow up in 1 week, 2 weeks and 1 month after the surgery. In the consecutive clinical cases, all patients reported minimal postoperative pain and discomfort (score ranged between 0 and 2). Both chewing and swallowing were not affected when wearing the stent, while four patients reported speaking inconvenience influenced by the stent. RESULTS: In the consecutive clinical cases, all patient reported minimal postoperative pain and discomfort (Score ranged between 0 and 2). Both chewing and swallowing were not affected when wearing the stent while four patients reported speaking influenced by the stent. CONCLUSION: The novel design of palatal stent reduces donor site morbidity and provides patient with a good healing experience after soft tissue harvesting from hard palate.

CD147 self-regulates matrix metalloproteinase-2 release in gingival fibroblasts after coculturing with U937 monocytic cells.

BACKGROUND: Cluster of differentiation 147 (CD147) is a multifunctional glycoprotein that functions as an inducer of matrix metalloproteinase (MMP) expression in fibroblasts. Synergistically enhanced MMP-2 expression was recently observed in the coculture of human gingival fibroblasts (HGFs) and U937 human monocytic cells; however, the responsible mechanisms have not yet been fully established. The aim of this study was to evaluate the release of soluble CD147 in HGFs after coculturing with U937 cells and its functional effect on the enhancement of MMP-2 expression in HGFs. METHODS: Enzyme-linked immunosorbent assay was used to determine the amount of CD147 protein in media, whereas real-time polymerase chain reaction was performed to evaluate the mRNA levels of CD147 and MMP-2 in HGFs and U937 cells. The enzyme activities of MMP-2 released from cells were examined by zymography. Transwell coculturing and conditioned media treatments were selected to rule out the effect of direct contact of HGFs and U937 cells. RESULTS: The protein and mRNA expression of CD147 in HGFs were enhanced after transwell coculturing with U937 cells and exposure to U937-conditioned medium. MMP-2 enzyme activities in HGFs were also significantly increased by the coculturing methods. Administration of exogenous CD147 enhanced MMP-2 expression in HGFs, whereas treatment with cyclosporine-A, which inhibited CD147 expression, reduced U937-enhanced MMP-2 expression in HGFs. CONCLUSIONS: CD147 can interact with fibroblasts to stimulate the expression of MMPs associated with periodontal extracellular matrix degradation. This study has demonstrated that CD147 released from fibroblasts might play a role in monocyte-enhanced MMP-2 expression in HGFs.

Risks of angled implant placement on posterior mandible buccal/lingual plated perforation: A virtual immediate implant placement study using CBCT.

BACKGROUND/PURPOSE: Immediate implant placement has been considered to be a successful treatment procedure. The bone plate perforation (BPP) may be one of severe complication and potentially life-threatening situation. The aim of this virtual study is to evaluate the influences of angled implant insertion on BPP during immediate implant installation in the posterior mandible. MATERIALS AND METHODS: Cone beam computed tomography images of 488 posterior teeth from 61 patients were selected. Virtual immediate implant placement (VIIP) was performed at each posterior tooth following the appropriate axis with the prosthetic-driven planning and different deviation angles of 3-, 6-, or 9-degree. BPP was then examined from cross-sectional images obtained. Furthermore, the relation of lingual bony morphology and BPP were also determined. RESULTS: The incidence of buccal and lingual BPP increased as the deviation angle increased in posterior mandible area. Incidence of lingual BPP was significantly influenced by angular deviation and type of lingual bony morphology after adjusting for age, gender, tooth type, and right/left side. An increase in incidence odds of over 6-fold (OR = 6.583) was noted for placements angled by 9° compared with placements made without angulation, and an increase in incidence odds of over 3-fold (OR = 3.622) was noted for teeth with the undercut-type lingual morphology compared with the other types. CONCLUSION: The present Results indicate that accurate selection of the implant insertion angle and full awareness of the bony anatomy at the implant recipient site are essential to prevent BPP in the posterior mandible.

Ameliorative effect of hesperidin on ligation-induced periodontitis in rats.

BACKGROUND: This study evaluated the ameliorative effect of hesperidin (HES), an anti-inflammatory flavanone, in rats with ligation (Lig)-induced periodontitis. METHODS: A total of 48 rats were randomly divided into non-ligation group (NL), Lig group, and two ligation-plus-HES groups (L+H). HES was administered immediately after ligature placement at a dose of 75 or 150 mg/kg by intragastric feeding. Destruction of the ligated maxillary second and mandibular first molars were evaluated by dental radiography, microcomputed tomography (micro-CT), and histometry performed after sacrificing the rats on the seventh day. The expression levels of interleukin (IL)-1ß, IL-6, and inducible nitric oxide synthase (iNOS) messenger (m)RNAs in the gingiva were determined by reverse-transcription polymerase chain reaction. The expression of iNOS was examined by immunohistochemistry. RESULTS: The dental radiography and micro-CT findings revealed significantly increased alveolar bone loss in the Lig group, which was significantly prevented by HES. The histometry results revealed less gingival inflammation and connective tissue loss in the L+H groups compared with that in the Lig group. The mRNA expression levels of IL-6, IL-1 ß, and iNOS were significantly increased in the Lig group but were reduced in the L+H groups. The immunostaining results showed that the ligation-induced iNOS expression was also decreased by HES. CONCLUSIONS: Oral administration of HES promotes an ameliorative effect against the ligation-induced alveolar bone loss and effectively inhibits the production of proinflammatory mediators in rats with experimentally induced periodontitis. Therefore, HES may be a good candidate for modulating oral inflammatory diseases.

Dental Pulp Stem Cell Transplantation with 2,3,5,4'-Tetrahydroxystilbene-2-O-ß-D-glucoside Accelerates Alveolar Bone Regeneration in Rats.

INTRODUCTION: Although the therapeutic potential of human dental pulp stem cells (hDPSCs) has been studied for bone regeneration, the therapeutic efficiency needs further consideration and examinations for clinical applications. Thus, the aims of this study were to evaluate the effect of 2,3,5,4'-tetrahydroxystilbene-2-O-ß-D-glucoside (THSG) on the osteogenic differentiation of hDPSCs and to examine the therapeutic efficiency of the THSG-enhanced osseous potential of hDPSCs in alveolar bony defects of rats. METHODS: Expressions of osteogenic messenger RNAs (including ALP, RUNX2, BGLAP, and AMBN) were examined by quantitative real-time polymerase chain reaction. Alizarin red S staining was conducted to analyze THSG-induced mineralization of hDPSCs. To investigate the regenerative effects of THSG-treated hDPSCs on dental alveolar bone, bony defects were created in male Sprague-Dawley rats. Defects were treated with Matrigel (Corning Inc, Corning, NY), hDPSCs, or hDPSCs + THSG. After 2 weeks, defect healing was evaluated by micro-computed tomographic and histologic analyses. RESULTS: In the cell model, THSG induced osteogenesis-associated genes (ALP, RUNX2, and BGLAP) and an enamel-related gene (AMBN), resulting in mineralization as detected by alizarin red S staining after 2 weeks of treatment. In the animal model, THSG increased all parameters of bone formation (the relative bone volume, trabecular thickness, trabecular number, and trabecular separation) in alveolar bony defects of rats. THSG not only improved the quality of newly formed bone but also the quantity of new bone. CONCLUSIONS: These results showed important findings in revealing the THSG-enhanced osteogenic differentiation of hDPSCs and THSG-facilitated bone regeneration, which may provide an alternative option for cell-based regenerative therapy.