[Effects of mineral trioxide aggregate and ethanolic extracts of Shandong propolis on the biological properties of human dental pulp fibroblasts].

OBJECTIVE: To evaluate the effect of mineral trioxide aggregate (MTA) and propolis from Shangdong province on the cell viability, mineralization and migration and anti-inflammatory ability of dental pulp fibroblasts. METHODS: The human dental pulp fibroblasts were cultured and subjected to 10 mg/L of propolis and 1:8 dilution of MTA extraction. The cell viability was evaluated with cell counting kit-8 (CCK-8) after 1, 5, 7 and 9 days. The cells in the upper inserts and the test culture media on the bottoms of 24-well plates interacted for 15 hours. Then the numbers of cells migrated through the permeable membranes were compared. The cells seeded in the 24-well plates were incubated in osteogenic medium with different materials for 21 days and stained with alizarin red S, then photographed. To evaluate the deposition of calcified matrix, the wells were destained with 100 mmol/L cetylpyridinium chloride. Finally, the cells were exposed to 1 mg/L lipopolysaccharide (LPS) to induce an inflammatory response, in the presence of propolis, MTA extraction. The cells were collected after 3 h, and the expressions of tumor necrosis factor-α (TNF-α), interleukin-1ß (IL-1ß) and interleukin-6 (IL-6) were determined using real-time polymerase chain reaction (real-time PCR). Statistical analysis was performed by one-way ANOVA and nonparametric tests (P<0.05). RESULTS: The cell viability of propolis group was significantly lower than those of MTA and control groups on days 5, 7 and 9, while MTA significantly increased the numbers of the viable cells on days 7 and 9. The migration cells of propolis group (26.67±2.52) were fewer than control group (61.33±4.93), and the cells of MTA group (80.00±2.65) were statistically more than those of the other two groups. The propolis group significantly induced more calcified matrix deposition than MTA group after 21 days of culture. Propolis significantly suppressed the expressions of IL-1ß and IL-6 after LPS exposure compared with MTA and control groups. CONCLUSION: The propolis from Shandong compared with MTA showed a certain degree of cytotoxicity, and had no significant effect on cell migration. On the other hand, propolis exhibited significant anti-inflammatory and mineralization promotion effect, suggesting that the active ingredients of propolis could be introduced as a supplement of pulp capping materials, or used as an irrigant or intracanal medicament due to its excellent anti-inflammatory effect. Propolis may have potential in vital pulp treatment of young permanent tooth suffering pulp inflammation.

Effect of propolis on preserving human periodontal ligament cells and regulating pro-inflammatory cytokines.

BACKGROUND/AIM: Propolis has been suggested as a storage medium for avulsed teeth. The aim of this study was to compare the effectiveness of Brazilian propolis with Hank's balanced salt solution and milk in maintaining the viability of human periodontal ligament cells, their osteogenic differentiation potential, and pro-inflammatory cytokine expression. MATERIAL AND METHODS: Cell Counting Kit 8 assays were performed to test human periodontal ligament cell viability in different storage media. The preservative effect on osteogenic differentiation was evaluated using alkaline phosphatase staining and activity assays, Alizarin Red S staining, and western blotting. Quantification of pro-inflammatory cytokines was performed using real-time PCR and enzyme-linked immunosorbent assays. RESULTS: Brazilian propolis at 10 µg/ml was not cytotoxic toward human periodontal ligament cells. The milk group showed the highest cell viability. Brazilian propolis and Hank's balanced salt solution groups showed similar cell viabilities. Alkaline phosphatase staining and activity were similar in all groups. Calcium deposition and mineralization nodule formation were similar in the Brazilian propolis and Hank's balanced salt solution groups, but were higher in the milk group. Osteogenic marker gene and protein levels were similar in all groups. The genes and protein expression levels of IL1ß, IL6, and IL8 decreased significantly after treatment with Brazilian propolis. TNFα mRNA expression showed no significant difference among the experimental groups. Pro-inflammatory cytokine levels in the milk group were higher than in the Brazilian propolis and Hank's balanced salt solution groups. CONCLUSIONS: Brazilian propolis, Hank's balanced salt solution, and milk maintained the viability of human periodontal ligament cells and preserved their osteogenic differentiation ability similarly. However, Brazilian propolis showed a better anti-inflammatory effect. This article is protected by copyright. All rights reserved.

[A multicenter prospective clinical trial on the effect of domestic bone level implants on single tooth implantation and restoration].

Objective: To evaluate the clinical application effects of a domestic bone-level implant system for restoring single tooth loss, and provide clinical evidence for the promotion and application of domestic implants. Methods: A prospective, multicenter clinical trial was conducted from April 2018 to January 2020 in three institutions: Department of Oral Implantology, School & Hospital of Stomatology, Wuhan University, Department of Stomatology, The First Affiliated Hospital of Zhejiang University School of Medicine, and Department of Stomatology, The Third Hospital of Hebei Medical University. The trial planned to include 100 patients for single tooth implantation and restoration, followed up for 1 year, to evaluate the implantation success rate and other related outcomes. Results: This study screened a total of 142 patients and ultimately included 100, comprising 43 males and 57 females with age of (47.0±12.2) years. Ninety-eight out of 100 patients completed a one-year follow-up (98.0%), while 2 patients terminated the trial early due to implant loosening (2.0%). After a one-year follow-up, the implants of the 98 patients were all functioning successfully, with a success rate of 98.0% (98/100). The patients were satisfied with the overall restoration effect. Conclusions: This study indicates that the domestic bone-level implant system has achieved favorable short-term clinical outcomes for single-tooth implantation and restoration.

[Expert consensus on the treatment of oral and maxillofacial space infections].

Oral and maxillofacial space infections (OMSI) are common diseases of the facial region involving fascial spaces. Recently, OMSI shows trends of multi drug-resistance, severe symptoms, and increased mortality. OMSI treatment principles need to be updated to improve the cure rate. Based on the clinical experiences of Chinese experts and with the incorporation of international counterparts' expertise, the principles of preoperative checklist, interpretation of examination results, empirical medication principles, surgical treatment principles, postoperative drainage principles, prevention strategies of wisdom teeth pericoronitis-related OMSI, blood glucose management, physiotherapy principles, Ludwig's angina treatment and perioperative care were systematically summarized and an expert consensus on the diagnosis and treatment of OMSI was reached. The consensus aims to provide criteria for the diagnosis and treatment of OMSI in China so as to improve the level of OMSI treatment.

Comparison of the postoperative and follow-up accuracy of articulator model surgery and virtual surgical planning in skeletal class III patients.

The aim of this study was to evaluate the postoperative and follow-up accuracy of using an intermediate occlusal splint between articulator model surgery (AMS) and virtual surgical planning (VSP) in double-jaw operations. Thirty skeletal class III patients were randomly allocated to have AMS or VSP. In the AMS group surgical planning was done through conventional articulator model surgery, and an intermediate occlusal splint made of acrylic resin was used. In the VSP group the surgical simulation was done virtually, and the same intermediate splint was used in the software and then fabricated using rapid prototyping technology. Preoperatively, one week postoperatively, and 1∼2-years later we obtained follow-up cone-beam computed tomographic (CT) images of each patient. Absolute linear differences between planned and actual outcomes, as well as planned and follow-up outcomes, were evaluated. There was no significant difference in either postoperative accuracy or follow-up accuracy between the methods, and there was no significant difference in the rate of skeletal relapse. Planning transfer by intermediate splint might therefore be the dominant factor in the final inaccuracies. The potentially greater accuracy of VSP may be realised with the help of new positioning devices instead of an intermediate splint.

[Evaluation of immediate implant in patients with limited buccal bone wall dehiscence in single upper anterior tooth].

Objective: To compare and evaluate the clinical outcome of immediate implant therapy in patients with limited buccal bone wall dehiscence and in patients with intact buccal bone wall. Methods: This prospective cohort study included patients intended to receive immediate implant treatment in upper anterior esthetic region in the Department of Implantology, Hospital of Stomatology, Wuhan University from August to December, 2018. Patients with buccal bone wall dehiscence limited to the coronal half were attributed to experimental group to conduct flap implant surgery (indicating to less than coronal half of the buccal bone wall length from the alveolar bone crest to the implant tip), whereas patients with intact buccal bone wall were attributed to control group to conduct flapless implant surgery. Buccal bone wall resorptions in height and thickness were evaluated 6 months after implant placement. Implant survival rate, pink/white esthetic score and post-operation complications were also analyzed 12 months after implant placement. Paired t-test and two-sample t-test were adopted to analyze the differences of different points within one group and differences between groups, respectively. Results: A total of 38 patients with the age of (39.2±5.8) years (range 19-45 years) and 38 upper anterior single tooth implants were included,in which 19 patients were attributed to experimental group [12 male and 7 female, the age was (37.6±5.3) years], and 19 patients were attributed to control group [9 male and 10 female, the age was (40.8±6.7) years]. Over the 12 months' observation after implant placement, the overall implant survival rate was 97% (37/38), and 18/19 in control group and 19/19 in experimental group. Only one implant lost in control group and no other complications were reported. Buccal bone resorption in thickness and height occurred in both groups within 6 months after implant placement. The thickness and height of buccal bone decreased significantly in both groups within 6 months after implant placement (P<0.05). Thickness decreases in experimental group were (1.32±0.74), (0.53±0.89) and (0.36±0.70) mm in coronal, middle and apical part of implant in experimental, and (1.24±0.57), (0.83±0.46) and (0.38±0.72) mm in coronal, middle and apical part of implant in control group. While the buccal bone height decreases were (0.24±0.15) mm in experimental group and (0.25±0.23) mm in control group. There were no statistical differences between the corresponding spots in the two groups (P>0.05). Upon the final restoration, both group got ideal pink esthetic scores [experimental group (10.92±1.13),control group (10.92±1.26)] and white esthetic scores [experimental group (7.61±0.78), control group (7.40±0.71)], the differences in both groups were not statistically significant (P>0.05). Conclusions: Clinical results of immediate implant to patients with buccal bone wall dehiscence limited to the coronal half are comparable to the results of patients with intact buccal bone wall.

[Establishment of a dexamethasone-induced congenital cleft palate model in New Zealand rabbits].

Objective: To develop a new congenital cleft palate model suitable for the evaluation of cleft palate surgery and other related treatments. Methods: Ten New Zealand female rabbits (aged 40 weeks, 4.5-5.0 kg) were selected. The next day after mating with male rabbits of the same strain was regarded as the day 1 of gestation (GD1). Ten pregnant rabbits were enrolled with intramuscular injection 1.0 mg dosage of dexamethasone once a day from GD13 to GD16. The caesarean section was performed to obtain the newborn rabbits on GD31 for each pregnant rabbit. Then the rates of the survival and cleft palate rabbits were calculated. The rabbits were divided into two groups according to the method of random number table (10 non-cleft palate rabbits as the control group and 10 cleft palate rabbits as the experimental group). The body weights and physiological behaviors of the rabbits were evaluated and recorded at the age of 1, 2 and 4 weeks respectively after being fed by using standardized gastric tube feeding method. At 4 weeks old, three rabbits in each group were randomly selected for the observation of local anatomy of different layers of the mouth and upper jaw. The anatomical results were photographed for comparative analysis. Results: In this experiment, 48 infants of 10 pregnant rabbits survived under the condition with a survival rate of 66% (48/73), among which the incidence of cleft palate was 60% (29/48). All the rabbits in the control group and the experimental group were able to survive for at least 1 month with stable weight gain. There was no significant difference in weight (P>0.05) and physiological appearance between the two groups. In cleft palate group, most of fetuses showed complete cleft palate with significant differences in the anatomical structure of the upper jaw compared with the control group including the changes in the morphology of the palatal mucosa, the terminal distribution of the soft palate muscles, and the dysplasia and absence of bone structures along the mid-maxillary line. Conclusions: In this study, it was the first time to successfully establish the dexamethasone-induced congenital cleft palate model in New Zealand rabbits for cleft surgical research.

Production of xylobiose from the autohydrolysis explosion liquor of corncob using Thermotoga maritima xylanase B (XynB) immobilized on nickel-chelated Eupergit C.

In this study, a thermostable recombinant xylanase B (XynB) from Thermotoga maritima MSB8 was immobilized on nickel-chelated Eupergit C 250L. This immobilized XynB was then used to hydrolyze the autohydrolysis explosion liquor of corncob (AELC) in a packed-bed enzyme reactor for continuous production of xylooligosaccharides, especially xylobiose. When tested in batch hydrolysis of AELC, the immobilized XynB still retained its relative activity of 92.5% after 10 cycles of hydrolysis at 90 degrees C. The immobilized XynB retained 83.6% of its initial hydrolysis activity even after 168 h of hydrolysis reaction at 90 degrees C and demonstrated a half-life time of 577.6 h (24 days) for continuous hydrolysis. HPLC showed that xylobiose (49.8%) and xylose (22.6%) were the main hydrolysis products yielded during continuous hydrolysis. Xylobiose was adsorbed on an activated charcoal column and eluted with a linear gradient of 15% (v/v) ethanol to yield xylobiose with 84.7% of recovery. Also, the purity of xylobiose was up to 97.2% as determined by HPLC. Therefore, the immobilized XynB was suitable for the efficient production of xylobiose from AELC. This is the first report on the immobilization of xylanase for xylobiose production.

[Aesthetic complications of immediate implant placement of anterior teeth].

In the anterior tooth zone, the criteria of successful implant restoration is not only to ensure a high survival rate of implant, but also to provide long-lasting and stable aesthetic outcomes. As for the rehabilitation of anterior teeth, immediate implant placement might achieve a survival rate similar to those of delayed implant placement and significantly reduce treatment time, whereas several aesthetic complications such as gingival recession, loss of interdental papilla, exposure of implant margin could also occur. Therefore, an important issue need to be solved is that how to avoid or handle the aesthetic complications of immediate implant placement of anterior teeth. This article mainly discusses the clinical features, possible etiologies and handling methods of aesthetics complications in rehabilitation of anterior teeth using immediate implant placement.

[New insight of craniofacial and oral findings of the RASopathies].

The RASopathies are a group of syndromes that have in common germline mutations in genes that encode components of the RAS/mitogen-activated protein kinase (MAPK) pathway and have been a focus of study to understand the role of this pathway in development and disease. These syndromes include Noonan syndrome (NS), NS with multiple lentigines (NSML), neu-rofibromatosis type 1 (NF1), Costello syndrome (CS), cardio-facio-cutaneous (CFC) syndrome, neurofibromatosis type 1-like syndrome (NFLS) and capillary malformation-arteriovenous malformation syndrome (CM-AVM). These disorders affect multiple systems, including the craniofacial complex. Although the crani-ofacial features have been well described and can aid in clinical diagnosis, the dental phenotypes have not been analysed in detail for each of the RASopathies. In this review, we summarize the clinical features of the RASopathies, highlighting the reported craniofacial and dental findings.

The influence of recombinant human BMP-2 on bone-implant osseointegration: biomechanical testing and histomorphometric analysis.

The healing period for bone-implant osseointegration lasts 3-6 months or even longer. The aim of this study was to investigate whether osseointegration can be enhanced by the use of bone morphogenetic protein-2 (BMP-2). In the femurs of 8 Japanese white rabbits, 16 implants were applied with 1.0 mg recombinant human BMP-2 (rhBMP-2) as group A, and the other 16 implants without rhBMP-2 as group B. Calcein green 20 mg/kg and alizarin red 20 mg/kg were injected 4 and 8 weeks after implantation, respectively. At 12 weeks, the animals were killed. In 16 implant-bone blocks, binding strength was measured by pull-out test, and the extracted implants were observed under a scanning electronic microscope. The other blocks were analysed for percentage of marked bone adjacent to the implant surface by confocal laser scanning microscope. The pull-out strengths of group A were greater than that of group B (P<0.05). Scanning electronic microscopy (SEM) showed more calcified substances on the surface of the implants of group A than B. There was more marked bone around group A than B implants at 4 weeks (P<0.05) and 8 weeks (P<0.05). rhBMP-2 improves the quantity and quality of implant-bone osseointegration. Biomechanical testing and histomorphometric analysis are reliable methods to use in researching the implant-bone interface.

Nucleofection is highly efficient for transfecting genes into murine embryonic palatal mesenchymal cells in primary culture.

Non-syndromic cleft of the lip and/or palate is one of the most common birth defects in humans. Embryonic palatal mesenchymal (EPM) cells are an attractive source for investigating embryonic palatal development. In this study, we developed a highly efficient transfection method for murine EPM (MEPM) cells. MEPM cells were transfected with the plasmid pEGFP-N1 using two non-viral methods: nucleofection and lipofection. Nucleofection provided a much better rate of gene transfer than lipofection particularly in MEPM cells. The methylenetetrahydrofolate reductase (MTHFR) gene is an important candidate for involvement in the pathogenesis of this birth defect. The RNA interference plasmid of MTHFR was constructed and nucleofected into MEPM cells. Successful transfection resulted in a remarkable reduction in the expression of MTHFR. Taken together, the results indicate that nucleofection is highly efficient for MEPM cell transfection, and that this approach may be useful for investigating gene function in the process of palatogenesis.

Parent satisfaction with primary repair of paediatric cleft lip in Southwest China.

The purpose of this study was to investigate the key factors in relation to parent satisfaction with the primary repair of paediatric cleft lip. One hundred and ninety-five children born with cleft lip and/or palate aged between 3 months and 1 year were recruited, along with their caregivers. All patients underwent primary cleft lip repair, and a telephone interview was held with their main caregivers at 3 months postoperative. The level of satisfaction with each item included in a simplified Cleft Evaluation Profile was ascertained and recorded. Patient clinical data were obtained from the medical records. One hundred and thirty-eight (71%) parents reported satisfaction with the general outcome of surgery. Parents were satisfied with the appearance of the lip and profile of the face, but were dissatisfied with the appearance of the nose and teeth. Mothers of patients showed lower satisfaction levels than fathers and grandparents. Parental satisfaction with the appearance of the lip was lower for patients without a cleft palate than for those with a cleft palate. The results of this study suggest that most Chinese parents of children who undergo primary cleft lip repair express satisfaction with the surgical outcomes. Satisfaction with the appearance of the nose and teeth is low and this needs to be improved. Other factors are likely to influence expressions of satisfaction.

Antiangiogenic scheduling of chemotherapy improves efficacy against experimental drug-resistant cancer.

To reveal the antiangiogenic capability of cancer chemotherapy, we developed an alternative antiangiogenic schedule for administration of cyclophosphamide. We show here that this antiangiogenic schedule avoided drug resistance and eradicated Lewis lung carcinoma and L1210 leukemia, an outcome not possible with the conventional schedule. When Lewis lung carcinoma and EMT-6 breast cancer were made drug resistant before therapy, the antiangiogenic schedule suppressed tumor growth 3-fold more effectively than the conventional schedule. When another angiogenesis inhibitor, TNP-470, was added to the antiangiogenic schedule of cyclophosphamide, drug-resistant Lewis lung carcinomas were eradicated. Each dose of the antiangiogenic schedule of cyclophosphamide induced the apoptosis of endothelial cells within tumors, and endothelial cell apoptosis preceded the apoptosis of drug-resistant tumor cells. This antiangiogenic effect was more pronounced in p53-null mice in which the apoptosis of p53-null endothelial cells induced by cyclophosphamide was so vigorous that drug-resistant tumors comprising 4.5% of body weight were eradicated. Thus, by using a dosing schedule of cyclophosphamide that provided more sustained apoptosis of endothelial cells within the vascular bed of a tumor, we show that a chemotherapeutic agent can more effectively control tumor growth in mice, regardless of whether the tumor cells are drug resistant.

Effects of cello-oligosaccharide on intestinal microbiota and epithelial barrier function of weanling pigs.

A total of 144 piglets (Duroc × Landrace × Yorkshire; average initial weight of 6.13 kg weaned at 21 ± 1 d age) were allotted to 4 treatments for 2 wk, each of which had 6 pens with 6 pigs per pen. After the feeding experiment, 6 pigs per treatment were slaughtered to investigate the effects of cello-oligosaccharide (COS) on intestinal microbiota and epithelial barrier function. The COS was added to the basal diet at 0, 1.5, 3.0, and 4.5 g/kg diet at the expense of corn, respectively. Plasma -lactate, diamine oxidase (DAO), and the Ussing chamber technique were used to determine the intestinal barrier function. 16S rRNA-based methods were used for intestinal microbiota analysis. The results showed that incremental levels of COS had no effect ( > 0.05) on growth performance. Incremental levels of COS increased lactobacilli in jejunal and colonic contents ( < 0.05); decreased in jejunal contents ( < 0.05) and and in colonic contents ( < 0.05); reduced plasma DAO (linear, = 0.013, and quadratic, = 0.037); increased jejunal mucosa DAO (linear, = 0.003, and quadratic, = 0.008); decreased fluorescein isothiocyanate dextran 4 kDa flux of jejunum and colon ( < 0.05); and increased transepithelial electrical resistance (TER) in colon ( < 0.05), claudin-1 protein expression in jejunal mucosa (linear, = 0.001, and quadratic, = 0.003), and protein expressions of claudin-1 and zonula occludens-1 (ZO-1) in colonic mucosa linearly ( = 0.001 and = 0.001, respectively) and quadratically ( = 0.001 and = 0.002, respectively). The results indicated that the improved microbial ecosystem in the presence of COS might contribute to improvement in intestinal barrier function and tight junction proteins. Results also showed that the appropriate dietary COS supplementation level was 3.0 g/kg in weaned pig diets under our trial conditions.

The in vitro demineralization potential of a sodium fluoride, calcium and phosphate ion-containing dentifrice under various experimental conditions.

While fluoride has had a dramatic effect in reducing the rate of caries, it has failed to provide complete protection against caries development, and tooth decay is still widely prevalent. The objective of this study was to determine the demineralization prevention potential of a remineralizing dentifrice with fluoride (Enamelon), and an assured supply of calcium and phosphate ions on bovine enamel in a cyclic remin/demin regimen using various experimental conditions. A conventional fluoride toothpaste, Crest, and a placebo dentifrice were used as controls. One-hundred and forty-four ground and polished 4 mm bovine enamel cores were prepared and assigned to various test treatments using six specimens per treatment group. They were subjected to six cyclic treatments consisting of one-minute exposures at room temperature to the test product diluted 1:2 in water, remineralization for a specified time at 37 degrees C, and demineralization for a specified time at 37 degrees C. The enamel specimens were tested for micro-hardness initially, and after the first, third and sixth treatment, remineralization and demineralization cycles using a Buehler Micro-hardness Tester with a 200 g load. Differences in micro-hardness between the test groups were analyzed for significance by performing multiple pair-wise comparisons using Bonferroni significance levels at the 95% confidence level. The results of this study showed that Enamelon Toothpaste was generally more effective in preventing demineralization of enamel than the fluoride dentifrice at 0.5 and 1.5 hours, and the non-fluoride control dentifrice at all time measurements. Prevention of enamel demineralization by the dentifrices was affected by changes in demineralization time and pH, but not by changes in remineralization time.

Parental craniofacial cephalometric features of Chinese patients with nonsyndromic isolated cleft palate.

To evaluate the parental craniofacial morphology in Chinese patients with sporadic nonsyndromic cleft palate, 175 parental pairs of children with nonsyndromic cleft palate (NSCP) and 206 controls from Sichuan University were involved in this study. Conventional cephalometric analysis was used to measure angles, linear distances and their ratios. Two-sample Student's t-tests and multivariate discriminant analysis were applied to the data. The data indicated that fathers of children with NSCP tended to have longer anterior cranial base length, palatal length, mandibular body length, mandibular ramus length, and longer mandibular height, lower face height, as well as larger nasal width, palatal width, mandibular body width, and condyle distance (p<0.05). Mothers of children with NSCP tended to have longer mandibular body length, mandibular ramus length, and longer mandibular height, lower face height, as well as larger nasal width, palatal width, mandibular body width, and condyle distance (p<0.05). The results indicated that the healthy parents of the patients with NSCP show distinct characteristics in craniofacial morphology. In general, the characteristics seem to be more distinct in the fathers of cleft patients than in the mothers.

[A dynamic functional comparative analysis of screw retained vs cement retained crowns under cyclic fatigue testing].

OBJECTIVE: To investigate the stability and mechanical characteristics of screw-retained and cement-retained crowns under dynamic cyclic fatigue testing. METHODS: Screw-retained and cement-retained crown samples were fixed on a 227 kg pressure transducer, through computer control cyclic fatigue testing was performed under a load of 15 kg on the sample during testing. Crown mobility was assessed in PTV value and the failure pattern of crowns were recorded. RESULTS: The initial PTV of cement-retained and screw-retained samples were not significant difference. The stability of the two group samples was no significant difference after testing. However the pattern of failure in two group samples was different. CONCLUSION: Both screw-retained and cement-retained methods may provide sufficient retentive force to keep stability of the crown in masticatory function.