Decreased GCF DEL-1 and increased GCF neutrophils with increasing probing pocket depth.

PURPOSE: Developmental endothelial locus-1 (DEL-1) plays a role in regulating neutrophil migration within the periodontium. The objective of this study was to evaluate the levels of DEL-1 in saliva and gingival crevicular fluid (GCF), as well as the number of neutrophils in patients with periodontitis. METHODS: Forty systemically healthy, non-smoking periodontitis patients participated in this study. Clinical periodontal parameters, including the plaque index, probing pocket depth (PPD), clinical attachment level, bleeding on probing, modified sulcular bleeding index, and marginal bone level, were measured. Levels of DEL-1, interleukin (IL)-1ß, IL-6, and IL-8 in unstimulated saliva samples, as well as DEL-1 in the GCF of 3 teeth from each participant, were assessed. Neutrophil counts in oral rinse and GCF samples were recorded. Spearman correlation coefficients were used to examine the correlation between protein levels, clinical parameters, and neutrophil quantities. Participants were divided into 2 age groups (those under 50 years and those 50 years or older) in order to investigate potential age-related differences. RESULTS: DEL-1 levels in the GCF showed a negative relationship with PPD (sum). Neutrophils in oral rinse samples were positively correlated with PPD, IL-8, and IL-1ß levels. Neutrophils in GCF exhibited a positive correlation with PPD (sum). Salivary DEL-1 levels showed correlations with IL-8 and IL-1ß, but not with the clinical parameters of periodontitis. CONCLUSIONS: The negative relationship observed between PPD and GCF DEL-1 levels is consistent with the proposed protective role of DEL-1.

Production of branched glucan polymer by a novel thermostable branching enzyme of Bifidobacterium thermophilum via one-pot biosynthesis containing a dual enzyme system.

Glycogen-like particles (GLPs) are applied in food, pharmaceutical, and cosmetics. The large-scale production of GLPs is limited by their complicated multi-step enzymic processes. In this study, GLPs were produced in a one-pot dual-enzyme system using Bifidobacterium thermophilum branching enzyme (BtBE) and Neisseria polysaccharea amylosucrase (NpAS). BtBE showed excellent thermal stability (half-life of 1732.9 h at 50 °C). Substrate concentration was the most influential factor during GLPs production in this system: GLPs yield and [sucrose]ini decreased from 42.4 % to 17.4 % and 0.3 to 1.0 M, respectively. Molecular weight and apparent density of GLPs decreased significantly with increasing [sucrose]ini. Regardless of the [sucrose]ini, the DP 6 of branch chain length was predominantly occupied. GLP digestibility increased with increasing [sucrose]ini, indicating that the degree of GLP hydrolysis may be negatively related to its apparent density. This one-pot biosynthesis of GLPs using a dual-enzyme system could be useful for the development of industrial processes.

Decontamination methods to restore the biocompatibility of contaminated titanium surfaces.

PURPOSE: The reaction of cells to a titanium implant depends on the surface characteristics of the implant which are affected by decontamination. The aim of this study was to evaluate the cytocompatibility of titanium disks treated with various decontamination methods, using salivary bacterial contamination with dental pellicle formation as an in vitro model. METHODS: Sand-blasted and acid-etched (SA) titanium disks were used. Three control groups (pristine SA disks [SA group]; salivary pellicle-coated SA disks [pellicle group]; and biofilm-coated, untreated SA disks [NT group]) were not subjected to any decontamination treatments. Decontamination of the biofilm-coated disks was performed by 14 methods, including ultrasonic instruments, rotating instruments, an air-powder abrasive system, a laser, and chemical agents. MG63 cells were cultured in the presence of the treated disks. Cell proliferation assays were performed on days 2 and 5 of cell culture, and cell morphology was analyzed by immunofluorescence and scanning electron microscopy (SEM). A vascular endothelial growth factor (VEGF) assay was performed on day 5 of culture. RESULTS: The cell proliferation assay revealed that all decontaminated disks, except for the 2 groups treated using a plastic tip, showed significantly less cell proliferation than the SA group. The immunofluorescence and SEM analyses revealed that most groups showed comparable cell density, with the exception of the NT group, in which the cell density was lower and bacterial residue was observed. Furthermore, the cells grown with tetracycline-treated titanium disks showed significantly lower VEGF production than those in the SA group. CONCLUSIONS: None of the decontamination methods resulted in cytocompatibility similar to that of pristine SA titanium. However, many methods caused improvement in the biocompatibility of the titanium disks in comparison with the biofilm-coated, untreated titanium disks. This suggests that decontamination is indispensable for the treatment of peri-implantitis, even if the original biocompatibility cannot be restored.

Myeloid sarcoma of the Gingiva with myelodysplastic syndrome: A Case Report.

The purpose of this report is to present a case of myeloid sarcoma of the gingiva with myelodysplastic syndrome.A 52-year-old male diagnosed with myelodysplastic syndrome with skin lesions presented with gingival swelling and gingival redness involving the maxillary left second premolar and the maxillary left first molar. The patient was referred from the Department of Hematology for a biopsy of the lesion. Full-thickness flaps were elevated and inflamed, and neoplastic soft tissue was removed from a lesion and the samples sent for histopathologic analysis.Histopathologic results showed leukemic cell infiltration beneath the oral epithelium, and the specimen was positive for the leukocyte marker. The diagnosis was myeloid sarcoma. Uneventful healing was observed at 2-week follow-up, but relapse of the lesions with the hyperplastic and neoplastic tissue was noted at 4-week follow-up. Further follow-up or treatment could not be performed because the patient did not visit at the next follow-up.In conclusion, myeloid sarcoma should be a diagnosis option for gingival growth because it can involve intraoral lesion. In this report, a biopsy was performed due to referral considering the patient's medical history. Although myeloid sarcoma in the oral cavity is extremely rare, a small biopsy and consultation with a hematologist may be beneficial for patients and may provide a differential diagnosis.

Effect of Asiasari radix on osteoblastic differentiation of stem cells derived from gingiva.

OBJECTIVE: To examine the dose-dependent impact of Asiasari Radix (A. radix) on the cell viability, differentiation and mineralization of stem cells derived from gingiva. METHODS: Stem cells that were derived from gingiva were grown in the presence of A. radix at final concentrations that ranged from 0.001 to 10 µg/mL. The morphology of the cells was viewed under an inverted microscope and the analysis of cell proliferation was performed by using Cell Counting Kit-8 (CCK-8) on day 1. The alkaline phosphatase activity test was used to assess differentiation and Alizarin red S staining was used to assess mineralization of treated cells. RESULTS: The control group showed spindleshaped, fibroblast-like morphology and the shapes of the cells in 0.001, 0.01, 0.1, 1 and 10 µg/mL of A. radix were similar to that of the control group at day 1. The cultures growing in the presence of 0.001 µg/mL of A. radix at day 1 showed an increase in the CCK-8 value (P < 0.05). Cultures growing in the presence of 0.001 µg/mL of A. radix presented the highest value for alkaline phosphatase activity (P > 0.05). Mineralized extracellular deposits were observed after Alizarin Red S staining and the cultures grown in the presence of 0.001 µg/mL of A. radix showed the highest value for quantitative results for bound dye (P < 0.05). CONCLUSION: Within the limits of this study, A. radix influenced the proliferation of stem cells derived from the gingiva and low concentrations of A. radix might enhance osteogenic differentiation of the stem cells.

Topographic analysis of the mandibular symphysis in a normal occlusion population using cone-beam computed tomography.

At present, the relationship between the morphological characteristics of the sympheseal region and occlusion has not been well documented. The aim of the present study was to investigate the following, using cone-beam computed tomography (CBCT): Interforaminal distance, the anterior loop, labial bone thickness at the tooth apex, cortical bone thickness, and the basal bone height from the apex of the tooth to the base of the mandible. Three-dimensional CBCT was performed on 20 normal occlusion subjects (9 males and 11 females; mean age=21.9±3.0 years); the mean interforaminal distance was 53.1±3.6 mm, with 85% of the participants demonstrating a mental foramen located below the second premolars on both sides. The mean anterior loop was 1.9±0.8 mm, the mean horizontal distance value was 4.5±1.3 mm, and the mean cortical bone thickness value was 2.3±0.5 mm. An increasing tendency for cortical bone thickness was seen from the central incisor to the second premolar. The mean vertical distance value was 20.3±3.1 mm. Decreasing tendency of vertical distance was seen from the central incisor to the second premolar. Furthermore, the width (mental foramina of both sides and their anterior loops), height (teeth apices and the inferior border of the mandible), depth (cortical bone thickness of the symphysis), and safety margins for vital anatomical structures (anterior loop, tooth apex, and inferior border of mandible) should be taken into account prior to symphyseal block-bone harvesting. The results of the present study suggested that a pre-operative evaluation with CBCT may be useful for diagnosis and treatment planning, and for minimizing complications during block-bone graft.

Instrumentation With Ultrasonic Scalers Facilitates Cleaning of the Sandblasted and Acid-Etched Titanium Implants.

Mechanical instrumentation is widely used to debride dental implants, but this may alter the surface properties of titanium, which in turn may influence bacterial adhesion and make it more difficult to remove the biofilm. This in vitro study was performed (1) to assess the amount of biofilm formation on a sand-blasted and acid-etched titanium fixture treated with ultrasonic scalers with metal, plastic, and carbon tips and (2) to evaluate how this treatment of titanium surfaces affects implant cleaning by brushing with dentifrice. The titanium fixtures were treated with various ultrasonic scaler tips, and surface roughness parameters were measured by confocal microscopy. Biofilm was formed on the treated fixtures by using pooled saliva from 10 subjects, and the quantity of the adherent bacteria was compared with crystal violet assay. The fixture surfaces with biofilm were brushed for total of 30 seconds with a toothbrush with dentifrice. The bacteria remaining on the brushed fixture surfaces were quantified by scanning electron microscopy. Surface changes were evident, and the changes of the surfaces were more discernible when metal tips were used. A statistically significant decrease in roughness value (arithmetic mean height of the surface) was seen in the 2 metal-tip groups and the single plastic-tip group. After brushing with dentifrice, the treated surfaces in all the treatment groups showed significantly fewer bacteria compared with the untreated surfaces in the control group, and the parts of the surfaces left untreated in the test groups. Within the limits of this study, treatment of titanium fixture surfaces with ultrasonic metal, plastic, or carbon tips significantly enhanced the bacterial removal efficacy of brushing. Thorough instrumentation that smooths the whole exposed surface may facilitate maintenance of the implants.

Evaluation of anatomical considerations in the posterior maxillae for sinus augmentation.

The edentulous posterior maxilla is considered a clinical challenge during dental implant treatment for many dental practitioners. This is because its insufficient bone quality, deficient alveolar ridge, spiny ridges, undercuts, and sinus pneumatization are often encountered after tooth loss. To overcome these problems, several approaches have been developed and are currently used, including sinus augmentation and bone augmentation. Today, two main procedures of sinus floor elevation for dental implant placement are in use: a two-stage technique using the lateral window approach, and a one-stage technique using a lateral or a crestal approach. In this study, we deal with the anatomic relations of the structures of the maxillary sinus during sinus augmentation. These anatomical findings can help in complications and potential injuries of the maxillary sinus procedures. It can be suggested that pre-operative evaluation is helpful for diagnosis and treatment planning and minimizing complication during the surgery.

Effects of Asiasari radix on the morphology and viability of mesenchymal stem cells derived from the gingiva.

Medicinal herbs used in traditional Oriental medicine, which have been in use clinically for thousands of years, are attractive sources of novel therapeutics or preventatives. Asiasari radix (A. radix) has been suggested for use in the treatment of dental diseases, including toothache and aphthous stomatitis. The aim of this study was to evaluate the effects of A. radix extracts on the morphology and viability of human stem cells derived from the gingiva. An Asiasarum heterotropoides extract was centrifuged and freeze-dried in a lyophilizer. Stem cells derived from the gingiva were grown in the presence of A. radix at concentrations ranging between 0.1 µg/ml and 1 mg/ml (0, 0.1, 1, 10, 100 and 1,000 µg/ml). Cell morphology was evaluated with an optical microscope and the viability of the cells was quantitatively analyzed with a cell counting kit-8 (CCK-8) assay for up to seven days. The untreated control group exhibited normal fibroblast morphology. The shapes of the cells following 0.1, 1, 10 and 100 µg/ml A. radix treatments were similar to those of the control group. However, a significant change was noted in the 1,000 µg/ml group on day 1, when compared with the untreated group. Furthermore, on day 7, the shapes of the cells following 100 and 1,000 µg/ml A. radix treatments were rounder and fewer cells were present, when compared with those of the control group. The cultures that grew in the presence of A. radix did not exhibit any changes in the CCK­8 assay on day 2; however, significant reductions in cell viability were noticed following 100 and 1,000 µg/ml A. radix treatment on days 5 and 7. Within the limits of this study, A. radix influenced the viability of the stem cells derived from the gingiva. Thus, the direct application of A. radix to oral tissues may produce adverse effects at high doses. Therefore, the concentration and application time of A. radix requires meticulous control to obtain optimal results. These effects require consideration, if the use of A. radix is planned for the treatment of dental diseases.

The effects of tetracycline-loaded silk fibroin membrane on proliferation and osteogenic potential of mesenchymal stem cells.

BACKGROUND: The main objective of this study was to investigate the effect of tetracycline-loaded silk fibroin membranes (TC-SFMs) on the proliferation and the osteogenic differentiation of human mesenchymal stem cells. MATERIALS AND METHODS: Four groups (0, 1, 5, and 10% concentration) of TC-SFMs were prepared for the experiments. We investigated cumulative tetracycline (TC) release profile for 7 d. Human gingiva-derived mesenchymal stem cells (GMSCs) were isolated from our previous study and seeded to the TC-SFMs. WST-8 assay (Cell Counting Kit-8; SigmaeAldrich Co, St. Louis, MO), staining of Phalloidin-FITC, and scanning electron microscope analyzed the cellular attachment and viability. Staining of Alizarin Red S (Sigma-Aldrich Co.) and osteogenic marker (osteocalcin) analyzed osteogenic differentiation. Additionally, quantitative polymerase chain reaction measured the expression of osteogenic lineage genes, including bone gamma-carboxyglutamic acid protein, bone sialoprotein, runt-related transcription factor 2, and collagen type I α1 according to TC concentration (0.05, 0.1, 0.25, and 0.5 mg/mL). RESULTS: The release of TC from TC-SFMs plateaued and neared completion in 24 h. Significantly higher viability was noted achieved in 1% and 5% TC-SFMs. The morphology of GMSCs on TC-SFMs at 0% and 1% concentration showed spindle shapes, but cells in 10% TC-SFMs appeared spheroid. During Alizarin Red S staining at 21 d of osteogenic differentiation, calcium and osteocalcin formation were significantly lower in the 10% TC-SFM group than in the 0, 1, and 5 groups. Compared with the control group, bone gamma-carboxyglutamic acid protein showed significantly low expression rate at TC concentration ≥0.05 mg/mL. Bone sialoprotein was low at TC concentration ≥0.1 mg/mL. Likewise, runt-related transcription factor 2 and collagen type I α1 were low at TC concentration of 0.5 mg/mL. CONCLUSIONS: Within the limits of this study, 1% and 5% TC-SFMs showed higher proliferation and osteogenic potential of GMSCs than 10% TC-SFM. Therefore, the use of 1% to 5% range of TC may be more suitable to silk fibroin membrane for stem cell tissue engineering.

The thickness of alveolar bone at the maxillary canine and premolar teeth in normal occlusion.

PURPOSE: The main purpose of this study was to investigate bone thickness on the buccal and palatal aspects of the maxillary canine and premolars using cone-beam computed tomography (CBCT). The differences between left- and right-side measurements and between males and females were also analyzed. METHODS: The sample consisted of 20 subjects (9 males and 11 females; mean age, 21.9±3.0) selected from the normal occlusion sample data in the Department of Orthodontics, The Catholic University of Korea. The thickness of the buccal and palatal bone walls, perpendicular to the long axis of the root were evaluated at 3 mm and 5 mm apical to cemento-enamel junction (CEJ) and at root apex. RESULTS: At the canines and first premolars regions, mean buccal bone thickness of at 3 mm and 5 mm apical to CEJ were less than 2 mm. In contrast, at the second premolar region, mean buccal bone thickness at 3 mm and 5 mm apical from CEJ were greater than 2 mm. Frequency of thick bone wall (≥2 mm) increased from the canine to the second premolar. CONCLUSIONS: This result should be considered before tooth extraction and planning of rehabilitation in the canine and premolar area of maxilla. Careful preoperative analysis with CBCT may be beneficial to assess local risk factors and to achieve high predictability of success in implant therapy.