[Correlation analysis between Pirani score and talo-navicular angle,calcaneo-cuboid angle and tibio-calcaneall angle of infant clubfoot under ultrasound].

Objective: To explore the evaluation effect of ultrasonography and Pirani score on tarsal deformity, treatment effect and pseudo-correction of congenital clubfoot in infants and young children, and the correlation between the two methods. Methods: This is a retrospective case series study. The clinical data of 26 children (40 feet) with congenital clubfoot who were evaluated by ultrasonography in the Third Affiliated Hospital of Zhengzhou University from January 2020 to January 2023 were retrospectively collected. There were 16 males and 10 females. The age at the first ultrasound examination was (M(IQR)) 9.0 (18.0) days (range: 1 to 46 days). All patients were treated with Ponseti method by the same physician. The Pirani scores before and after treatment and at the last examination, and the talonavicular angle, calcaneocuboid angle and tibiocalcaneal angle measured by ultrasound were collected, and the treatment and follow-up were recorded. Paired sample t test, repeated measures analysis of variance or Kruskal-Wallis test were used for data comparison, and Spearman correlation analysis was used for correlation analysis. The receiver operating characteristic curve was used to calculate the efficacy of ultrasound in evaluating different Pirani scores. Results: The number of plaster fixation in 26 children was 4.0 (1.0) times (range: 2 to 8 times). The medial talonavicular angle and posterior tibiocalcaneal angle were significantly improved after treatment and at the last follow-up compared with those before treatment, and the differences were statistically significant (all P<0.01). There was no difference in lateral calcaneocuboid angle before and after treatment and at the last follow-up (F=1.971, P>0.05). Pseudo-correction occurred in 2 cases (2 feet) during the treatment, with an incidence of 5%. Correlation analysis showed that there was a moderate positive correlation between talonavicular angle and Pirani midfoot score (r=0.480, P<0.01). There was no correlation between calcaneocuboid angle and Pirani midfoot score (r=0.114, P=0.105). There was a moderate negative correlation between tibial heel angle and Pirani hindfoot score (r=-0.566, P<0.01). The cut-off point of Pirani midfoot score of 1.5 was 38.78°, the sensitivity was 0.90, the specificity was 0.56, and the area under the curve was 0.75. The cut-off value of angle was 27.51 °, the sensitivity was 0.16, the specificity was 0.92, and the area under the curve was 0.44.The cut-off points of Pirani midfoot score of 3.0 were 45.08°and 9.96°, the sensitivity was 0.94 and 0.91, the specificity was 0.37 and 0.42, and the area under the curve was 0.59 and 0.62, respectively. The cut-off values of Pirani hindfoot score of 2.0 and 3.0 were 167.46° and 160.15°, respectively. The sensitivity was 0.75 and 0.67, the specificity was 0.81 and 0.83, and the area under the curve was 0.78 and 0.71, respectively. Conclusion: Ultrasound can complement with Pirani score, visually and dynamically observe the morphology and position changes of talonavicular joint, calcaneocuboid joint and tibiotalocalcaneal joint, monitor the recovery and pseudo-correction of tarsal bones, and better evaluate the therapeutic effect.

[Effects of novel bioactive glasses on promoting remineralization of artificial dentin caries].

OBJECTIVE: To investigate the effects of novel bioactive glasses (BG) including PSC with high phosphorus component and FBG with fluorine-doped element on promoting remineralization of artificial dentin caries. METHODS: (1) BGs were used in this study as follows: PSC (10.8%P2O5-54.2%SiO2-35.0%CaO, mol.%) were synthesized using phytic acid as the phosphorus precursor through sol-gel method. FBG (6.1%P2O5-37.0%SiO2-53.9%CaO-3.0%CaF2, mol.%) and 45S5(6.0%P2O5-45.0%SiO2-24.5%CaO-24.5%Na2O, mol.%) were synthesized by traditional melt method. (2) The above BGs were soaked in simulated body fluid (SBF) for 24 hours. Then X-ray diffraction (XRD) was used to analyze the formation of hydroxyapatite (HA) crystals. (3) Prepared 1 mm thick dentin slices were soaked in 17% ethylene diamine tetraacetic acid (EDTA) for 1 week to demineralize the dentin. Then the dentin slices treated by BG were soaked in SBF for 1 week. Field emission scanning electron micro-scopy (FE-SEM) was used to observe the surface morphology of the dentin slices. (4) Four cavities were prepared to 1 mm depth in each 2 mm thick dentin slice, then were treated with lactic acid for 2 weeks to form the artificial dentin caries. Wax, mineral trioxide aggregate (MTA), PSC and FBG were used to fill four cavities as blank control group, MTA group, PSC group and FBG group respectively. Then the spe-cimens were soaked in SBF for 4 weeks. The changes of depth and density of demineralized dentin were analyzed using Micro-CT before filling and after 2 and 4 weeks filling. RESULTS: (1) PSC and FBG promoted mineral formation on the surfaces of the demineralized dentin. And the speed was faster and crystallinity was higher in PSC group than the FBG and 45S5 groups. (2) The increased mineral density of artificial dentin caries in PSC group were (185.98 ± 55.66) mg/cm3 and (213.64 ± 36.01) mg/cm3 2 and 4 weeks after filling respectively, which were significantly higher than the control group [(20.38 ± 7.55) mg/cm3, P=0.006; (36.46 ± 10.79) mg/cm3, P=0.001]. At meanwhile, PSC group was also higher than MTA group [(57.29 ± 10.09) mg/cm3; (111.02 ± 22.06) mg/cm3], and it had statistical difference (P=0.015; P=0.006). The depth of remineralized dentin in PSC group were (40.0 ± 16.9) µm and (54.5 ± 17.8) µm 2 and 4 weeks respectively, which were also statistically different from the control group (P =0.010;P=0.001). There were no statistical differences between the control group and MTA group. The above effects of FBG group were between PSC and MTA. CONCLUSION: PSC has advantages in the speed, quality and depth of mineral deposition in the demineralized layer of artificial dentin caries. It would be expected to be an ideal material to promote the remineralization of dentin caries.

[Research progress in vital pulp therapy in mature permanent teeth with carious pulp exposure].

Vital pulp therapy(VPT)is an important pathway to preserve and maintain pulp tissue in a healthy state. VPT has been improved recently as the new progress achieved in pathobiology, bioactive materials and clinical research. The present review summarizes the clinical outcomes and prognostic factors of VPT, including direct pulp capping, partial pulpotomy and full pulpotomy in mature permanent teeth with carious pulp exposure, and briefly introduces the new progress in this field.

[Effect of digital virtual simulation system for preclinical teaching of access and coronal cavity preparation].

Objective: To investigate the effectiveness of a digital virtual simulation training system applied in the preclinical teaching of access and coronal cavity preparation. Methods: Twenty dental undergraduate students from Peking University School and Hospital of Stomatology were recruited and divided randomly and equally into two groups according to the random number method after being unified with theory training, including access and coronal cavity preparation skills assessment form and Simodont system operation manual. Tests for access and coronal cavity preparation skills by using standard simulation plastic teeth were performed and the scores were recorded as baseline for each student. Students in group of virtual simulation priority were trained using Simodont virtual simulation system, while those in group of phantom-simulator priority were trained using conventional phantom-simulator system. Access and coronal cavity preparation skills of standard simulation plastic teeth were assessed once again and recorded as the second scores for the two groups. Furthermore, the two groups of students exchanged training systems and were assessed and graded once more as the third scores. Finally, all students were asked to fill up a Teaching Questionnaire after the training. The data were then collected and analyzed. Results: For the group of virtual simulation priority, after the training by using Simodont virtual simulation system and conventional phantom-simulator system, the mean score of access and coronal cavity preparation (16.00±1.49) was significantly higher than the baseline score (13.30±1.41) (P<0.05). For the group of phantom-simulator priority, after the training by using conventional phantom-simulator system and Simodont virtual simulation system, the mean score of access and coronal cavity preparation (15.60±1.26) was also significantly higher than the baseline score (13.00±1.89) (P<0.05). Furthermore, in the group of virtual simulation priority, of which the students were trained by using Simodont virtual simulation system first and then conventional phantom-simulator system, the score of access and coronal cavity preparation was significantly higher than the score of training by using conventional phantom-simulator system only (14.30±1.77) (P<0.05). In the group of phantom-simulator priority, of which the students were trained by using conventional phantom-simulator system first and then Simodont virtual simulation system, the score of access and coronal cavity preparation was significantly higher than the score of training by using Simodont virtual simulation system only (14.10±1.45) (P<0.05). Moreover, in the group of virtual simulation priority, the score of training by using conventional phantom-simulator system after using Simodont virtual simulation system was significantly higher than that of training by using Simodont virtual simulation system only (P<0.05). The results of the questionnaire showed that the students fully agreed that "the Simodont virtual simulation system has the characteristics of repeatability, multi-dimension and multiple practice, and provides me with more attention to details" [80% (16/20)], however "it needs to be improved and upgraded to be close to the conventiaonl phantom-simulator system" [90% (18/20)]. Conclusions: Compared with using the conventional phantom-simulator system only, the preclinical teaching effectiveness of access and coronal cavity preparation could be effectively improved by using Simodont virtual simulation system combined with the phantom-simulator training system and might influenced by the training sequence.

[Effects of bioactive glass on proliferation, differentiation and angiogenesis of human umbilical vein endothelial cells].

OBJECTIVE: To investigate the effects of phytic acid derived bioactive P2O5-SiO2-CaO gel-glasses (PSC) on the proliferation, differentiation and angiogenesis of human umbilical vein endothelial cells (HUVECs) in vitro. METHODS: HUVECs were cultured in PSC extracts, which were prepared with endothelial cell medium (ECM) at a gradient concentration of 0.01, 0.1, 1 and 2 g/L. Cells cultured in ECM were used as the control. The effect of PSC on HUVECs proliferation was assessed on the 1st, 3rd, 5th, 7th and 10th days with (4, 5-dimethylthiazol-2-yl) 2, 5-diphenyltetrazolium bromide assay (MTT), and the optimum PSC concentration for HUVECs proliferation was used in the following experiments. The subsequent experiments were divided into two groups. The experimental group used PSC extracts to culture HUVECs (PSC group) and the control group used ECM to culture HUVECs (ECM group). Gene expression of angiogenic factors, vascular endothelial growth factor (VEGF) and basic fibroblast growth factor (bFGF), was detected on the 2nd, 4th and 7th days by real-time reverse transcription-polymerase chain reaction (real-time RT-PCR). The morphology and number of tubules formation were observed at the 4th and 10th hours. Image J software was used for counting and quantitative analysis. RESULTS: The results of MTT assay showed that 0.1 g/L PSC group had the most significant effect on promoting HUVECs proliferation. The optical density values of 0.1 g/L PSC group on the 5th and 7th days were significantly higher than those of the other PSC groups and the control group (P < 0.05). The result of real-time RT-PCR showed that 0.1 g/L PSC extract up-regulated the mRNA expression of VEGF and bFGF significantly (P < 0.05). On the 4th day, the gene expressions of VEGF and bFGF in PSC group were 1.59 and 1.45 times higher than those in ECM group respectively, and on the 7th day, the gene levels of VEGF and bFGF in PSC group were 1.98 and 1.37 times higher than those in ECM group respectively. The tubule formation assay showed that the maturity and density of the tubules in 0.1 g/L PSC group was much better than that in the ECM group at the 10th hour. The quantitative analysis by Image J indicated that the tubules number in PSC group (29.63±2.29) was higher than in the ECM group (20.13±2.36), with statistical significance (P < 0.05). CONCLUSION: PSC showed significant promoting effects on HUVECs' proliferation, differentiation and angiogenesis in vitro.

[Clinical efficacy observation of direct pulp capping using iRoot BP Plus therapy in mature permanent teeth with carious pulp exposure].

Objective: To evaluate the clinical efficacy and influence factors of direct pulp capping using a bioactive ceramic in mature permanent teeth with carious pulp exposure, in order to explore the feasibility and indications of vital pulp therapy for such teeth. Methods: From January 2016 to September 2017, 57 patients (57 teeth) with carious pulp exposure in mature permanent teeth were selected from the Department of Cariology and Endodontology, Peking University School and Hospital of Stomatology. All the teeth were preoperatively diagnosed as deep caries with normal pulp or reversible pulpitis. After rubber dam isolation, all the carious dentin was removed and the exposed pulp tissue was observed under microscope. Hemostasis should be achieved within 3 min by using 2.5% sodium hypochlorite cotton pellets with a gently press. A resin composite restoration was performed immediately or 2 weeks later after direct pulp capping by using a bioceramic material (iRoot BP Plus). The patients were re-examined 12 to 50 months after operation (average 30 months) and the outcomes were evaluated by symptoms, clinical examination and X-ray. Kaplan-Meier survival analysis was used to calculate the success rate and influence factors were analyzed by Log-Rank test. Results: Totally 50 patients [age (32±13) years old (13-68 years old), 12 males and 38 females] received the follow-up examination more than one year. The overall success rate was 90% (45/50) and the success rates at 1 year, 2 years, 3 years and more were 98%, 89% and 81%, respectively. Age, gender, symptom, tooth and cavity type, pulpal exposure size and coronal restoration material had no significant correlations with the treatment outcome (P>0.05). Conclusions: Direct pulp capping of mature permanent teeth with carious pulp exposure by using iRoot BP Plus might have high success rate. There's no significant correlations between the major clinical factors and the treatment outcome.

LncRNA SNHG8 promotes cell migration and invasion in breast cancer cell through miR-634/ZBTB20 axis.

OBJECTIVE: Small nucleolus RNA Host Gene 8 (SNHG8) belongs to a subgroup of long non-coding RNAs. SNHG8 is upregulated in many cancers, such as gastric cancer, liver cancer, and esophageal squamous cell cancer. However, whether SNHG8 is abnormally expressed in breast cancer and its biological functions remain unclear. Therefore, our research intended to determine the expression status of SNHG8 in breast cancer, explore the effects of SNHG8 on the development of breast cancer, and investigate the potential molecular mechanisms in cancer progression. PATIENTS AND METHODS: The expression levels of SNHG8 were detected in tissue samples and cell lines via qRT-PCR. The effects of SNHG8 on viability of breast cancer cells were detected via CCK-8, EdU, transwell, and flow cytometry analyses. RESULTS: qRT-PCR results showed that the expression level of SNHG8 was significantly upregulated in tumor tissues and cell lines. Gene functional studies showed that the downregulation of the expression level of SNHG8 significantly inhibited the breast cancer cells migration and invasion, and induced apoptosis. Meanwhile, we found that SNHG8 served as an inhibitor of miR-634 in tumor tissues. SNHG8 may participate in the malignancy of breast cancer by sponging the miR-634 to increase the expression level of ZBTB20. CONCLUSIONS: The SNHG8-miR-634-ZBTB20 pathway may be a potential target for the treatment of breast cancers.

[Analysis of the efficacy of the Ponseti method for treatment of secondary clubfoot in young children with tethered cord syndrome].

Objective: To explore the feasibility of Ponseti method in treatment of secondary clubfoot in young children with Tethered Cord Syndrome(TCS). Methods: The clinical data of 53 young children with clubfeet treated with Ponseti method from March 2014 to March 2017 at Department of Pediatric Orthopedics, the Third Affiliated Hospital of Zhengzhou University were analyzed retrospectively. These patients were divided into TCS group and Idiopathic group according to the etiology. There were 19 patients (33 feet) in TCS group,with an mean age of 2.8 months(range:0.2 to 24.0 months), including 13 males and 6 females, 5 patients with unilateral clubfeet and 14 patients with bilateral clubfeet. There were 34 patients (45 feet) in idiopathic group, with an mean age of 3.1 months(range: 0.1 to 21.0 months), including 18 males and 16 females, 23 patients with unilateral clubfeet and 11 patients with bilateral clubfeet. All the children received casts correction according to Ponseti method, and were followed up at 3 weeks, 3 months, 6 months and every 6 months after the Achilles tendon tenotomy or the last cast correction. Complications were recorded and therapeutic effect was evaluated of these children by Dimeglio Scoring System and the International Clubfoot Study Group (ICFSG) at the last follow-up. Independent t test, Mann-Witney U test or χ(2) test were used to compare the indicators of the two groups. Results: The number of plaster fixation in TCS group was (6.1±2.0) times, and that of idiopathic group was (4.8±1.0) times(t=3.482, P<0.01).In TCS group, 22 feet treated with Achilles tendon transection and that of idiopathic group was 40 feet(χ(2)=0.279, P=0.598). There were 18 cases recurrence in TCS group and 8 cases in Idiopathic group (t=11.149, P<0.01). In TCS group, 16 cases (27 feet) completed the initial correction, the success rate was 60.6% (27/33), 3 cases (6 feet) could not correct the deformity after 9 to 10 times of plaster fixation, and then underwent soft tissue release.In idiopathic group, 34 cases (45 feet) achieved initial correction after Ponseti treatment(χ(2)=6.488, P=0.011).At the last follow up, there were 5 cases (9 feet) in TCS group and 2 cases (2 feet) in idiopathic group underwent soft tissue release(χ(2)=6.110, P=0.013). The classification grade of ICFSG score of the two groups without soft tissue release were (2.1±0.6) and (1.8±0.7), the difference was not statistically significant (t=1.765, P=0.082). All the children had no skin ulceration, bedsores, skin allergy and other complications. Conclusion: Ponseti method is effective in the treatment of clubfoot secondary to TCS, and the functional recovery is similar to that of children with idiopathic clubfoot.

[Effect of bioactive glass pretreatment on the durability of dentin bonding interface].

OBJECTIVE: To study the effect of bioactive glass (BG) on the dentin bond strength and the microleakage of hybrid layer. METHODS: In the study, 30 dentin planes were prepared from the third molars with no caries and equally assigned to the control group, BG group, and sodium trimetaphosphate (STMP)-polyacrylic acid (PAA)-BG group (S-P-BG group), randomly. After etched with 35% phosphoric acid, the dentin planes of BG group were pretreated with 0.5 g/L BG, and the dentin planes of S-P-BG group were pretreated with 5% STMP, 5% PAA and 0.5 g/L BG. No additional pretreatment was done to the dentin planes of control group. Then the dentin planes were bonded using 3M Single Bond 2 adhesive to 3M Z350XT composite resin, and cut into 0.9 mm×0.9 mm column samples, which were stored at 37 ℃ artificial saliva (AS). After 24 hours, 1 month, and 3 months, the microtensile bond strength test was performed. The data were analyzed using one-way ANOVA and LSD method. The morphology of the bond fracture interface was observed with scanning electron microscope. Other 27 teeth were collected and the enamel layer and roots cut off, with the pulp chamber exposed. 0.1% rhodamine B was added to the 3M Single Bond 2 adhesive, and then the adhesive was applied to complete the bonding procedures as above. The teeth were stored in 37 ℃ AS for 24 hours, 1 month, 3 months, and then 0.1% sodium fluorescein solution was placed in the chambers and stained for 1 hour. Confocal laser scanning microscopy was used to observe the interface morphology and microleakage of the hybrid layer. RESULTS: At the end of 24 hours and 1 month, there was no significant difference in the microtensile bond strength among the three groups (P>0.05). After 3 months of soaking, the S-P-BG group [(36.91±7.07) MPa] had significantly higher microtensile bond strength than the control group [(32.73±8.06) MPa] (P=0.026); For the control group and the BG group, the microtensile bond strength significantly decreased at the end of 3 months compared with 24 hours (control group: P=0.017, BG group: P=0.01); The microtensile bond strength of S-P-BG group af the end of 3 months had no significant difference in compared with 24 hours [(37.99±7.98) MPa] (P>0.05). Observation of the fracture surface at the 24 hours showed no obvious mineralization in all the three groups. After 1 and 3 months, mineral formation was observed in BG group and S-P-BG group, and no obvious collagen exposure was observed in S-P-BG group. Confocal laser scanning microscopy revealed no obvious differences in the morphology and quantity of the resin tag in the control group, BG group and S-P-BG group. At the end of 24 hours, leakage was found in all the three groups. The microleakage of the control group increased at the end of 3 months, while the microleakage of the BG and S-P-BG groups decreased. CONCLUSION: BG pretreatment of dentin bonding interface can induce mineralization at the bonding interface and reduce the microleakage of the hybrid layer; pretreating the dentin bonding interface with STMP, PAA and BG may enhance the maintaining of the dentin bonding durability.

[Anti-inflammatory and repaired effects of non-steroidal anti-inflammatory drugs on human dental pulp cells].

OBJECTIVE: To study the effects of non-steroidal anti-inflammatory drugs (NSAIDs) on anti-inflammation and repair of human dental pulp cells (hDPCs). METHODS: Primary hDPCs from the freshly extracted human third molars were cultured and passaged in vitro, and the following experiments were performed using the 4th-6th generations of hDPCs. HDPCs were cultured in Dulbecco's modified eagle medium (DMEM) containing 1 mg/L lipopolysaccharide (LPS) to obtain LPS irritated hDPCs (LPS-hDPCs), which served as the inflammatory positive group. LPS-hDPCs in the experimental group were cultured in DMEM containing different concentrations (1, 10, and 100 µmol/L) of NSAIDs (aspirin or meloxicam). HDPCs cultured in DMEM were used as the negative control group. The effects of NSAIDs on the proliferation of hDPCs were assessed on the 1st, 3rd, 5th, and 7th day by MTT assay. The effects of NSAIDs on the expression of inflammation related genes interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α) of LPS-hDPCs were detected at the 6th hour by real-time PCR. The expression of differentiation related markers dentin matrix protein-1 (DMP-1) and dentin sialophosphoprotein (DSPP) were detected on the 7th day by real-time PCR. The effects of NSAIDs on the mineralization of LPS-hDPCs were assesd on the 14th day by alizarin red staining. Calcium mineralized nodules were semi-quantitatively determined by cetyl pyridine chloride. RESULTS: MTT assay showed that 1-100 µmol/L aspirin or meloxicam significantly promoted the proliferation of hDPC in a concentration dependent manner (P<0.05). Real-time PCR showed that 1-100 µmol/L meloxicam or 100 µmol/L aspirin down-regulated significantly the mRNA expression of TNF-α and IL-6 of LPS-hDPCs (P<0.05), and 100 µmol/L meloxicam down-regulated IL-6 and TNF-α more significantly than 100 µmol/L aspirin of LPS-hDPCs (P<0.05). Real-time PCR showed that 100 µmol/L meloxicam up-regulated the mRNA expression of DMP-1 and DSPP of LPS-hDPCs significantly (P<0.05). Alizarin red staining showed the meloxicam at the concentration of 100 µmol/L significantly promoted the mineralization of LPS-hDPCs (P<0.05). CONCLUSION: In this study, meloxicam promoted the proliferation of hDPCs, inhibited the inflammatory reaction and promoted differentiation and mineralization of hDPCs under LPS irritation. The present results suggest that meloxicam may play a role in anti-inflammation and repair of pulp inflammation.

[Physical and chemical properties of pulp capping materials based on bioactive glass].

OBJECTIVE: To investigate the physical and chemical properties of pulp capping materials based on bioactive glass (BG). METHODS: Novel BG pulp capping materials were composed of powder and fluid. The powder was BG (82.36% SiO2, 15.36% CaO, and 2.28% P2O5) synthesized by using the sol-gel method combined with template technology. Two kinds of fluid were provided: (1) phosphate buffer (PB) solution and (2) phosphate buffer solution with 1% sodium alginate (SA) addition. After mixing the powder and fluid, BG-PB and BG-PB-SA were prepared. Setting time and compressive strength of the BG pulp capping materials were tested by setting time loading system and mechanical testing machine. Statistical analysis was performed using the independent sample t-test, with the significance set at 0.05. pH meters was used to test the pH of the BG pulp capping materials and mineral trioxide aggregate (MTA). The sealing ability of the BG pulp capping materials and MTA was tested by methylene blue dye leakage model. Statistical analysis was performed using one-way ANOVA analysis and LSD multiple comparison, with the significance set at 0.05. RESULTS: (1) Setting time: the initial and final setting time of BG-PB were (7.2±0.3) min and (12.7±0.9) min, respectively. And the initial and final setting time of BG-PB-SA was (7.5±0.3) min and (13.6±1.6) min. There was no significant difference between BG-PB and BG-PB-SA groups (P>0.05). (2) Compressive strength: the compressive strength of BG-PB was (16.5±1.8) MPa at 1 day and (14.1±3.7) MPa at the end of 28 days. However, the compressive strength of BG-PB-SA was (26.6±6.3) MPa on day 1 and (21.6±5.6) MPa on day 28, which was significantly higher than that of BG-PB (P<0.05). (3) pH: the pH of BG pulp capping materials' bulk immersed in simulated body fluid (SBF) went up to 8.06, and the highest pH of MTA was 8.47. Significant difference was observed between the BG pulp capping materials and MTA (P<0.05). (4) Sealing ability: the optical density (D) in positive control group was significantly higher than ln BG-PB, BG-PB-SA and MTA groups (P<0.05). And BG-PB and BG-PB-SA showed the similar favorable sealing ability with MTA, and no significant difference was observed among the three groups (P>0.05). CONCLUSION: The novel BG pulp capping materials showed good physical properties, especially BG's setting time was short; BG pulp capping materials are promising.

[Mesoporous nano-bioactive glass microspheres as a drug delivery system of minocycline].

OBJECTIVE: To construct mesoporous nano-bioactive glass (MNBG) microspheres load-release minocycline as an antibacterial drug delivery system. METHODS: Sol-gel method was used to synthesze MNBG microspheres as drug carrier. The MNBG consisted of SiO2, CaO, and P2O5. According to the content of silicon, MNBG microspheres were divided into four groups (60S, 70S, 80S and 90S). Scanning electron microscopy (SEM) was used to observe the surface characteristic and particle size of MNBG; Nitrogen adsorption-desorption experiment was performed to calculate the MNBG's specific surface area and the pore sizes; The Fourier transform infrared spectrum (FT-IR) and the thermogravimetric analysis were conducted to calculate the loading efficiencies of minocycline hydrochloride; UV spectrophotometric was used to determine the cumulative release of minocycline from drug-loaded particles in PBS solution within 21 d. Agar diffusion test (ADT) was performed to evaluate the antibacterial properties on Enterococcus faecalis. The inhibition zone was observed and the diameter was measured. RESULTS: The MNBG microspheres had good dispersion, large surface area, and even particle size. The pore sizes ranged from 4.77 nm to 7.33 nm. The loading experiment results showed that the minocycline hydrochloride loading efficiency of MNBG was related to the pore size of the microspheres. Among 60S, 70S, 80S and 90S, 60S MNBG had the highest loading efficiency of 16.33% due to its high calcium content and large pore sizes. A slow minocycline release rate from MNBG particles in PBS solution until d 21 was observed. It was showed that a burst release of 28% of the total drug for the first 24 h. A cumulative release of 35% was found, and the final concentration of minocycline maintained at about 47 mg/L. ADT showed that mino-MNBG had inhibitory effect on the growth of Enterococcus faecalis. 1 g/L minocycline, 1 g/L mino-MNBG, and 0.1 g/L minocycline presented inhibition zone, however, PBS and 1 g/L MNBG didn't. The diameter of the inhibition zone of minocycline groups was significant larger than that of mino-MNBG group (P<0.05), which was also significant larger than those of PBS and MNBG groups (P<0.05). It showed that mino-MNBG drug delivery system had antibacterial properties on Enterococcus faecalis. CONCLUSION: The 60S MNBG that can effectively load and release minocycline may be an ideal drug carrier.

[Nano-sized bioactive glass enhances osteogenesis of critical bone defect in rabbits].

OBJECTIVE: To compare the osteogenic effects of a nano-sized 58S bioactive glass (nano-58S BG) and a traditional 45S5 bioactive glass(45S5 BG) in penetrating parietal critical bone defects. METHODS: Critical bone defect with 9 mm diameter was created in the parietal bone of New Zealand rabbits. The bone defects were then filled with either nano-58S BG, or 45S5 BG, or nothing but the newly-formed blood clot as the blank control at random. For histological observation, specimens were gained 4 and 8 weeks after the surgery, sectioned and stained by HE. The amount of collagen type I was observed with Picric-Sirius Red staining through polarimetry. To observe the new bone formation with fluorescence under the laser confocal microscope, we injected fluorescent markers 14, 28, and 42 days after the surgery. The markers were tetracycline hydrochloride, alizarin red and calcin individually in chronological order. Image J software was used to quantify the bone regeneration. RESULTS: HE staining showed that BG particulates were integrated with the surrounding tissue without any inflammatory cells infiltration 4 weeks after surgery. New bone regeneration was observed both from the border and in the center of the defects in both BG groups. No bone regeneration in defect center was observed in control group. At the end of 8 weeks, there was more bone regeneration in nano-58S group compared with 45S5 group and control group. The structure of the new bone in BG groups was hollow, which was similar to the natural normal parietal bone. No hollow structure was observed in the new bone of control group. Picric-sirius Red polarimetry showed that more amount of collagen type I was found in nano-58S group than in either 45S5 or control group. The fluorescent observation of the hard tissue slices at the end of 8 weeks showed statistically larger scope and faster new bone formation in nano-58S group with (29.4±4.48) µm thickness from 4-6 weeks and (35.3±3.74) µm from 6-8 weeks compared with 45S5 group [(13.43±3.44) µm and (17.64±4.13) µm] and control group [(5.88±2.92) µm and (6.07±3.02) µm, P<0.01]. CONCLUSION: Compared with the traditional 45S5 bioactive glass, 58S nano-sized bioactive glass showed better osteogenic effect in bone regeneration in parietal bones of rabbits.

[Influence of the Arg-Gly-Asp-Ser sequence on the biological effects of bioactive glass on human dental pulp cells].

OBJECTIVE: Positive effects of bioactive glass (BG) on proliferation, mineralization, and differentiation of human dental pulp cells (hDPCs) was already verified in various former studies. The Arg-Gly-Asp-Ser sequence (RGDS) was confirmed of affecting cell adhesion. Before further investigation, the objective of this study is to investigate whether RGDS can affect the effects of BG on the adhesion, proliferation and mineralization of hDPCs. METHODS: hDPCs were harvested from third molars of 18-25-year-old individuals after informed consent. Enzyme digestion technique was used. The 4th to 6th generation of hDPCs were used for all experiments. The cells of the experimental groups were cultured in Dulbecco minimum essential medium (DMEM) containing ionic dissolution products of BG and RGDS of several concentrations (12.5 mg/L, 25.0 mg/L, 50.0 mg/L, 100.0 mg/L, 200.0 mg/L). DMEM containing ionic dissolution products of BG without RGDS was used for cell culture as control group. Cell adhesion was tested 4 h after cell seeding by MTT assay. Cell proliferation was examined at 1, 3, 5, 7, and 9 d after cell seeding by MTT assay. Cell mineralization was investigated on days 14 and 28 by alizarin red staining. After being stained and dried, mineralized nodules were dissolved by cetylpyridinium chloride (CPC) for semi-quantitative test. Results were statistically analyzed by one way ANOVA, SPSS (version 19.0) and P<0.05 was considered to be significant. RESULTS: Cell adhesion in BG group showed no difference from that in DMEM group. Compared with BG group, hDPCs in BG+RGDS groups suggested weaker cell adhesion.When the concentration of RGDS increased, the adhered cell number decreased. hDPCs cultured with BG and RGDS showed lower proliferation activity in the early stage, while no significant difference was observed after 3 d. BG group promoted the mineralization of hDPCs compared with positive control group, negative control group and RGDS group. No significant difference was observed between BG+RGDS group and BG group or between RGDS group and positive control group. CONCLUSION: BG promotes proliferation and mineralization without affecting cell adhesion of hDPCs. Unbounded RGDS inhibits cell adhesion, but has no influence on the positive effects of BG on the proliferation and mineralization of hDPCs.

[Effects of bioactive glass and extracted dentin proteins on human dental pulp cells].

OBJECTIVE: To investigate the proliferation, odontogenic differentiation and mineralization of human dental pulp cells (HDPCs) on bioactive glass(BG) and extracted dentin proteins(EDP). METHODS: Primary HDPCs were isolated from third molars by enzyme digestion and were cultured in Dulbecco's minimum essential medium (DMEM). Then the 4th generation of HDPCs was cultured with DMEM, which contained BG-EDP, BG, and EDP, respectively. Meanwhile HDPCs were cultured in DMEM as control group. Proliferation of HDPCs was evaluated by 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide (MTT) colorimetric assay. Odontogenic differentiation was determined by alkaline phosphatase (ALP) activity assay and real-time PCR. Mineralization was investigated by Alizarin red staining and cetylpyridinium chloride (CPC) assay. RESULTS: The proliferation of HDPCs was increased significantly in BG-EDP group on 3,7,and 9 d (optical density value: 1.36±0.06, 2.52±0.20, 2.72±0.29) compared with BG (optical density value: 1.20±0.26, 2.33±0.26, 2.50±0.30), EDP(optical density value: 1.13±0.15, 2.10±0.13, 2.38±0.22) and control group (optical density value: 0.84±0.17, 1.84±0.18, 1.95±0.19), P<0.05. After 7 days, ALP activity of BG-EDP group had no statistical difference compared with EDP group and control group; the expression of odontogenic differentiation genes (DSPP, DMP-1) showed no difference among all the groups(P>0.05). After 14 days, ALP activity of BG-EDP group (56.67±1.83) was significantly upregulated compared with EDP group (41.98±9.71) and control group (30.82±6.70), P<0.05, but had no statistical difference compared with BG group (56.29±6.20), P>0.05; DSPP gene expression was upregulated significantly in BG-EDP group (5.79±1.94) compared with the other groups (P<0.05); DMP-1 gene expression of BG-EDP group (3.87±1.87) increased but had no statistical difference compared with the other groups (P>0.05). The alizarin red staining showed more mineral nodules in BG-EDP group, the cetylpyridinium chloride semi-quantification presented higher calcification in BG-EDP group (0.27±0.01) compared with the other groups (P<0.05). CONCLUSION: Compared with either BG or EDP, BG-EDP significantly promotes the proliferation, odontogenic differentiation and mineralization of HDPCs.

[Digital imaging fiber optic transillumination (DIFOTI) method for determining the depth of cavity].

OBJECTIVE: To analyze the accuracy of the digital imaging fiber optic transillumination (DIFOTI) on diagnosis of caries lesions depth using DIAGNOcam system. METHODS: This experiment adopted self-matching design. Seventy-four extracted teeth (molar: sixty-six, premolar: eight) with one caries lesions in proximity which were not damaged in surface marginal ridge were selected. Dental calculus and dental stains were removed from the extracted teeth for standby application. A sign was marked in the middle of the occlusal surface edge at the side of decay. Then the teeth were fixed in the standard model of dentition and cavities were adjacent with the sound tooth surface. Sticky wax was applied to seal the level of 2 mm beyond cemento-enamel junction (CEJ) in the direction of occlusion and interproximal space to imitate gingival margin and gingival papilla. The standard models of dentition was seated in imitation head mold. The lesions depth degree was looked into and checked with DIAGNOcam system. Besides, the pictures on the occlusal surfaces were recorded and saved. The sign above could be seen on the picture. The measuring tool in DIAGNOcam system was used to measure the depth of the caries from the sign (as starting point) to the deepest point of caries in the pictures and its length was recorded for a. The line a was lengthened to the contralateral edge of occlusal surface in the photo and the length was recorded for b. A line from the marked point on the occlusal surface edge of the extracted teeth was draw parallel to the line b on the corresponding photo and its length was recorded for c. The depth of the cavities on the projected images was recorded for d, and calculated d/a=c/b (digital optical fiber measured decay depth/caries damage depth of the image=actual tooth width/tooth width of the image), and d=c/b×a inferred. At last, the teeth were taken out from the standard model dentition. The decay of the tooth was removed completely. The actual depth of the cavity was recorded for D. The difference between d and D was recorded for Δd. The software of SPSS 20.0 was used to test the consistency of the results, and the MedCalc 14.8.1.0 software was used for Bland-Altman analysis. RESULTS: The intraclass correlation coefficient (ICC) between d and D was 0.951 (ICC>75%), P=0.263. There was a function relationship y=0.23+0.91x between d(x) and D(y). Bland-Altman analysis method showed that the mean of Δd (Δdmean) was 0.05 mm, the standard deviation of Δd (ΔdSD)=0.308, and the 95% confidence interval was (-0.55 to 0.65). The amplitude of difference was clinically acceptable. So the consistency of the two measurement modes was high. CONCLUSION: There was no significant difference between the depth of caries lesions checked with DIAGNOcam system and the depth of the actual cavity, and the consistency was very good. The vitro study suggests that the DIAGNOcam system may be used to assess the depth of caries cavity as a useful tool in diagnosis and treatment.

CD133 induced tumorigenicity mice express TGF-beta receptor type II (TBRII) and embryonic liver fodrin (ELF) along with stem cell markers.

OBJECTIVE: Cancer stem cells play a major role in developing hepatocellular carcinoma (HCC), and they are not well identified in in vivo settings. Also, their occurrence and specificity are not well defined in different pathological stages of the tumor. CD133 is a cancer stem cell specific marker which also lacks to specify all the cancer stem cell population and similarly different markers fails to identify cancer stem cells. To overcome this multi marker helps to identify the cancer stem cells with maximum coverage and aids to understand their expression in different pathological stages of HCC. MATERIALS AND METHODS: In this study, we compared the expression of CD133 along with TBRII and ELF using Immunohistochemistry and western blotting technique that probably helps to reveal the nature of cancer stem cells in different pathological stages of HCC. RESULTS: We initially develop CD133 induced tumorigenicity mice with HCC and compared their tissue morphology using histology. The histological data reveal that as tumor progress, the cell proliferative ability increase together with a large nucleus. The Immunohistochemical data against CD133 shows a prominent increase in their expression as tumor progress, but we found out that the tumor suppressor related proteins, TBRII and ELF shows increased expression in primary tumor stages to prevent tumor initiation, but neither of them shows prominent up-regulation in metastasis stages of the tumor. CONCLUSIONS: Our results conclude that the tumor suppressor proteins TBRII and ELF shows elevated expression pattern in the primary stage, but in advance stages its expression gets down-regulated and that fails to control metastasis stage.

[In vitro study of biological characteristics of new retrograde filling materials iRoot].

OBJECTIVE: To study the biological characteristics of new retrograde filling materials iRoot BP plus and iRoot FS. METHODS: (1) The roots were cut into 3 mm in length, and the root canals were prepared to 1 mm in diameter, followed by being filled with iRoot BP plus, iRoot FS, or mineral trioxide aggregate (MTA). The specimens were immersed in simulated body fluid (SBF). The ability of mineralization in vitro was detected through three studies. First, the mineralization of specimens was analyzed through scanning electron microscope observations and energy dispersive X-ray spectrometer. Then, the pH of SBF was monitored using pH meter. (2) The extracts were gained by immersing blocks of iRoot BP plus, iRoot FS, and MTA (8 mm diameter and 2 mm height) into dulbecco's modified eagle medium (DMEM). The effects of the extracts on proliferation of MG63 cells were detected through MTT assay. The gene expression level of alkaline phosphatase (ALP) was analyzed by quantitative real-time PCR, and the expression of ALP activity was observed by ALP activity staining. RESULTS: (1) The formation of minerals could be observed on the surfaces of iRoot BP plus, iRoot FS, and MTA at the end of 24 h, and there were more amounts of apatite aggregated after 14 days. The values of Ca/P ratios of apatites were 1.43, 1.39, and 1.51, respectively. (2) The pH of SBF could be raised to 8.09±0.07, 7.91±0.06, and 8.11±0.06, respectively, significantly higher than the blank. (3) The extracts of iRoot BP plus, iRoot FS, and MTA of dilutions of 1:5 and 1:10 presented no effect of proliferation of MG63 cells. (4) iRoot BP plus and iRoot FS could significantly up-regulated the levels of ALP messenger RNA expression, while there was no obvious difference in ALP staining among the iRoot BP plus, iRoot FS, MTA, and the blank. CONCLUSION: The present study shows that iRoot has displayed good mineralization capability in vitro and capability to promote differentiation and mineralization of MG63 cells, inferring that iRoot may have good bioactivity.

Plaque pH and associated parameters in relation to caries.

Intensified plaque acidogenicity in caries-prone subjects was reported many years ago, but emerging evidence has suggested that the relationship may not be as strong as once thought. We have now determined a range of acidogenicity variables in subjects having both caries prevalence and incidence data, and have included plaque mineral data in the analysis. pH measurements were made in 20 randomly selected subjects from a high-caries group (mean DMFS = 8. 95) and 20 from a caries-free group of Beijing children aged 12 years participating in a caries prediction study. Subgroups with a 12-month DMFS increment >/=2 or = 0 were also formed from the two groups, respectively. Measurements were made with an iridium oxide electrode inserted between teeth 13/14, 23/24, 34/35 and 44/45, before and every 5 min for 30 min after rinsing with 10% sucrose, and the 4 resulting 'Stephan curves' averaged using a plaque pH analysis program. Supragingival plaque was collected from buccal and lingual smooth surfaces of posterior and upper anterior teeth and its acid extract analysed for Ca, P and F. Caries-free subjects (based on past experience) had a significantly higher maximum plaque pH and pH value after 30 min (reflecting a faster return to resting pH), a lower minimum enamel dissolution capacity of plaque and recorded less time below pH 7.0 than did high-caries subjects. No other differences were significant, including those of the principal acidogenic parameters 'minimum pH attained after a sugar rinse', 'curve area below the critical pH of 5.5' and 'time below the critical pH'. Selection of the caries groups on the basis of both experience and incidence did not reveal significant differences in more parameters. Upper arch plaque was significantly more acidogenic than lower arch plaque, and there was a consistently strong association between upper and lower arch values in individuals. Ca, P and F in the subjects' plaque had little or no influence on the principal acidogenic parameters. Our failure to find a relationship between caries prevalence or activity and these principal acidogenicity parameters may be related to differences between fissure and smooth surface plaque, temporal variations in acidogenicity and/or to use of F toothpaste during the 1-year observation period. These results support the view that factors such as the frequency of acidogenic episodes may be more important in caries progression than the degree of acidogenicity during any one episode.

Ultrastructural cytochemical study of enzymes expressed by signet ring cells in gastric cancer.

AIM: To study the ultrastructural localization of five marker enzymes (ALPase, ACPase, G6Pase, TPPase and CCOase) in gastric cancer signet ring cells to demonstrate their biologic behaviors. METHODS: Five marker enzymes were examined in signet ring cells of seven gastric cancer patients by ultrastructural enzyme cytochemical techniques. RESULTS: The number of corresponding organelles and the activities of marker enzymes, especially ACPase and TPPase, increased, leading to stronger mucus synthesis, secretion and digestion in gastric cancer signet ring cells. There was a lack of collagenous fibers in the stroma around the cancer nests. CONCLUSION: Signet ring cell carcinoma is very invasive with metastasis rates due to the secretion of proteolytic enzymes.