Category: Nevin Manimala

Shanghai Kou Qiang Yi Xue. 2024 Feb;33(1):54-58.

ABSTRACT

PURPOSE: To compare the forming ability of four kinds of nickel-titanium instrument preparation resin for simulated curved root canal.

METHODS: A total of 40 single bend resin simulated root canals were randomly divided into 4 groups with 10 in each group. Four kinds of nickel-titanium instruments (ProTaper, HyFlex EDM, WaveOne Gold and Reciproc Blue) were used for root canal preparation, and divided into group A, group B, group C and group D. The preparation time of the four groups was compared, the root canal images before and after preparation were analyzed by computer image analysis software, and the changes of the preparation time, curvature and curvature radius of the four groups were recorded. With the root tip as the center of the circle, the radius of 1-10 mm was selected as concentric circle arcs. The detection points were overlapping root canal intersection points. The resin removal amount and center positioning force of the inner and outer walls of the root canal at different detection points were recorded. Statistical analysis was performed with SPSS 20.0 software package.

RESULTS: The root canal preparation time in group A was significant longer than that in group B, C and D(P＜0.05), but there was no significant difference in the curvature and curvature radius of the root canal among the four groups (P＞0.05). The removal amount of resin from the root canal wall in group C was significant lower than that in group A, B and D (P＜0.05) when the distance from the detection point to the apical foramina was 5, 6, 8, 9 and 10 mm, respectively. The removal amount of resin from the outer wall of the root canal in group C was significant lower than that in group A, B and D (P＜0.05) when the distance from the detection point to the apical foramina was 5, 6, 7, 9 and 10 mm, respectively. The root tip offset of group A from the detection point to the apical hole of 1, 2, 3, 4, 6, 7, 8, 9 and 10 mm was significant greater than that of group B, C and D(P＜0.05).

CONCLUSIONS: Among the four instruments, ProTaper has the largest apical deviation, HyFlex EDM, WaveOne Gold and Reciproc Blue have better ability of root canal forming.

PMID:38583025

Shanghai Kou Qiang Yi Xue. 2024 Feb;33(1):49-53.

ABSTRACT

PURPOSE: To study the antimicrobial effect of different concentrations of new bioactive glass(BG) on common bacteria in apical periodontitis of deciduous teeth.

METHODS: The diameter (mm) of the inhibitory rings formed after treatment of Enterococcus faecalis, Porphyromonas gingivalis and Clostridium nucleatum with the new bioactive glass was detected and observed by paper diffusion method, and the minimal inhibitory concentration(MIC), minimal bactericidal concentration (MBC) and minimal biofilm eradication concentration (MBEC) of E. faecalis, P. gingivalis and C. pseudomallei were determined. The mixed plaques of the three bacteria were treated with 20, 40, 60 and 80 mg/mL of the new bioactive glass for 24 h. The results were analyzed by laser confocal microscopy. The antibacterial effect of the new bioactive glass on the mixed plaque was observed by confocal laser scanning microscopy (CLSM). Statistical analysis was performed with GraphPad Prism 10.0 software.

RESULTS: The new bioactive glass showed strong antibacterial potential against the common bacteria of apical periodontitis; the MBEC of the new bioactive glass on the plaque was significantly greater than MIC and MBC of Enterococcus faecalis, Porphyromonas gingivalis and Clostridium nucleatum, and as the concentration of the new bioactive glass increased, the number of dead bacteria in the mixed plaque increased, and there was significant difference from that of the blank control group (P＜0.05).

CONCLUSIONS: The novel bioactive glass shows significant antibacterial efficacy against Enterococcus faecalis, Porphyromonas gingivalis and Clostridium nucleatum, which are the common bacteria in apical periodontitis of deciduous teeth.

PMID:38583024

Shanghai Kou Qiang Yi Xue. 2024 Feb;33(1):40-48.

ABSTRACT

PURPOSE: To explore the cytotoxic effect of a menthol-favored E-liquid on human periodontal ligament stem cells (hPDLSCs), as well as the underlying mechanism of electronic cigarette (E-cig)-induced cell apoptosis.

METHODS: PDLSCs were isolated and cultured from periodontal ligament tissues of healthy premolars extracted for orthodontic reasons. Cells in passage 3 were used to detect the surface markers of stem cells by flow cytometry. Then the cells were exposed to different doses of menthol-favored E-liquid (at 59 mg/L nicotine concentration) in the culture median (the final nicotine concentrations were 0.1 μg/mL, 1.0 μg/mL, 10 μg/mL, 50 μg/mL, 0.1 mg/mL, 0.2 mg/mL and 0.5 mg/mL, respectively) for different period of times (24, 48 and 72 h). The cell viability was analyzed by CCK-8 assay. Cell apoptosis was evaluated by flow cytometry (7-AAD and Annexin V staining) and TUNEL assay. Reactive oxygen species (ROS) production was detected with fluorescence probe DCFH-DA by confocal microscopy and flow cytometry. The protein expression levels associated with ROS/JNK/caspase 3 axis(p-JNK, JNK, c-Jun, p-c-Jun, Bcl-2, Bax and cleaved-caspase 3) were analyzed by Western blot. Immunocytofluorescense staining was applied to evaluate the expression level of p-JNK. After addition of NAC, a ROS scavenger, and MAPK/JNK specific blocker SP600125, their effects on E-cig-induced cell apoptosis were evaluated. Statistical analysis was performed with Graph Pad 5.0 software package.

RESULTS: Human PDLSCs were successfully isolated and cultured and flow cytometry assay showed the mesenchymal stem cell surface biomarkers (CD73, CD90 and CD105) were positively expressed. CCK8 assay indicated cell viability was significantly(P＜0.001) different among all concentration groups at various time points (24, 48 or 72 h), and the difference in apoptosis rate among all concentration groups was also statistically significant (P＜0.001). After exposure to E-liquid with nicotine concentration ≥50 μg/mL, cell viability was significantly reduced, and the proportion of apoptotic cells and the cellular ROS level was significantly increased in a dose-dependent manner as compared with the control group(0.0 mg/mL). Western blot assay showed E-cig exposure could promote MAPK/JNK phosphorylation in a dose-dependent and time-dependent manner. Either NAC or SP600125 could partially rescue the E-cig-induced cell apoptosis via reversing up-regulation of p-JNK and cleaved caspase 3.

CONCLUSIONS: ROS/JNK/caspase 3 axis is involved in menthol-favored E-liquid-induced apoptosis of hPDLSCs.

PMID:38583023

Shanghai Kou Qiang Yi Xue. 2024 Feb;33(1):36-39.

ABSTRACT

PURPOSE: To study the effect of different cleaning methods on the shear bond strength of self-adhesive resin cement to saliva-contaminated high translucency zirconia and surface wettability.

METHODS: Eighty zirconia specimens were randomly divided into 5 groups (n=16), i.e., control group(not contaminated), 75% ethanol group,cleaning paste group,airborne-particle abrasion group, and atmospheric pressure cold plasma group. The contact angles was measured, shear bond strength were examined, and fracture types were determined. SPSS 26.0 software package was used for statistical analysis of the data.

RESULTS: The atmospheric pressure cold plasma group produced the lowest contact angle(P＜0.05). The shear bond strength of the airborne-particle abrasion group, the cleaning paste group and the atmospheric pressure cold plasma group respectively were similar to the control group without significant difference(P＞0.05), while those were significantly higher than 75% ethanol group(P＜0.05). The mixed fracture mode of the atmospheric pressure cold plasma group evidently increased.

CONCLUSIONS: Airborne-particle abrasion, cleaning paste and atmospheric pressure cold plasma overcome the effects of saliva contamination, producing the shear bond strength to zirconia similar to the control group. The atmospheric pressure cold plasma improves hydrophilicity of high translucency zirconia significantly.

PMID:38583022

Shanghai Kou Qiang Yi Xue. 2024 Feb;33(1):30-35.

ABSTRACT

PURPOSE: To explore the mechanism of SETDB1 inhibiting epithelial mesenchymal transition (EMT),migration and invasion in oral cancer via SOX 7 methylation.

METHODS: SETDB1 and SOX7 mRNA and protein expression levels in KB cells of oral cancer and oral mucosal epithelial ATCC cells were determined by qRT-PCR and Western blot (WB). SETDB1 si-RNA was structured, then transfect into KB cells of oral cancer by liposome-mediated method. siRNA-SETDB1 was the experimental group (si-S), siRNA empty vector was the negative control group (si-N), and untransfected KB cells were the blank control group(NC). SETDB1 mRNA and protein expression levels were detected by qRT-PCR and Western blot(WB), to verify the transfection effect. The methylation levels of SOX7 were determined by pyrosequencing. The expression of N-cadherin, Vimentin, β-catenin, and Slug proteins was detected by WB. Cell viability was measured by MTT assay, migration ability was tested by scratch healing assay, and invasion ability was tested by Transwell chamber assay. Statistical analysis was performed with SPSS 21.0 software package.

RESULTS: The results of Rt-qPCR and WB showed that the SETDB1 mRNA and protein expression decreased significantly in si-S group(P＜0.05). Pyrosequencing test results showed that the regulation of SETDB1 could significantly reduce the SOX7 methylation rate and increased the SOX7 protein expression. WB results showed that knockdown of SETDB1 significantly inhibited the expression of EMT-related proteins N-cadherin, Vimentin, β-catenin and Slug in oral cancer KB cells (P＜0.05). The results of cell functology experiments showed that knockdown of SETDB1 could significantly inhibit survival, migration and invasion of KB cells.

CONCLUSIONS: Downregulation of SETDB1 could suppress EMT, migration and invasion of oral cancer cells by regulating SOX7 methylation level, providing new ideas and targets for the diagnosis and treatment of oral cancer.

PMID:38583021

Shanghai Kou Qiang Yi Xue. 2024 Feb;33(1):22-29.

ABSTRACT

PURPOSE: To investigate the role and mechanism of connexin 43（Cx43）in odontoblast differentiation of human dental pulp cells (hDPCs) induced by lipopolysaccharide (LPS).

METHODS: The maxillary first molar injury model of SD rats was established. The expression pattern of Cx43 in dental pulp repair after injury was detected by immunofluorescence(IF) staining. hDPCs was respectively stimulated with 0, 1, 10, 100 and 1 000 ng/mL LPS for 6 h to screen the optimal concentration, and then the expression of Cx43 was inhibited and overexpressed in hDPCs. Quantitative real-time PCR(qRT-PCR) and Western blot(WB) were used to detect the expression of Cx43 and dentin sialophosphoprotein (DSPP), dental matrix protein-1 (DMP-1), osterix (Osx) and extracellular signal-regulated kinase (ERK) activity. Furthermore, hDPCs were treated with specific Cx43 channel inhibitors to investigate the effect of Cx43-mediated channel activity in odontoblast differentiation of hDPCs, and to explore the role and mechanism of Cx43 in regulating odontoblast differentiation of hDPCs induced by LPS. Statistical analysis was performed with SPSS 26.0 software package.

RESULTS: IF results showed that Cx43 was mainly expressed in the odontoblast layer in healthy dental pulp tissues. At 3-24 h after tooth injury, the expression of Cx43 decreased and then gradually increased to the normal level; from 3 days to 2 weeks after injury, the expression of Cx43 tended to be down-regulated which was in the odontoblast layer and pulp proper. The expression of DSPP mRNA was significantly up-regulated in the hDPCs stimulated with 10 ng/mL LPS for 6 h(P＜0.01). Inhibition of Cx43 significantly up-regulated the expression of DSPP, DMP-1 and Osx mRNA induced by LPS in hDPCs(P＜0.05), while overexpression of Cx43 obviously inhibited the expression of factors related to LPS-induced odontoblast differentiation(P＜0.01) and the fluorescence intensity of DSPP. 10 ng/mL LPS activated ERK signal in hDPCs, and overexpression of Cx43 significantly attenuated the activity of ERK signal induced by LPS(P＜0.01). Inhibition of Cx43-mediated hemichannel (HC) promoted mRNA expression of factors related to odontoblast differentiation in hDPCs and the activity of ERK signal induced by LPS(P＜0.05), while blocking Cx43-mediated gap junction channel (GJC) inhibited odontoblast differentiation.

CONCLUSIONS: Cx43 participates in the regulation of dental pulp repair after injury, and its expression shows a downward trend as a whole. Inhibition of Cx43 or blocking of HC promotes LPS-induced ERK signal activity and odontoblast differentiation of hDPCs.

PMID:38583020

Shanghai Kou Qiang Yi Xue. 2024 Feb;33(1):13-21.

ABSTRACT

PURPOSE: To clarify the effect of genistein(GEN) on osteogenic differentiation and explore the effect of GEN loaded by platelet-rich fibrin (PRF) on the repair process of bone defects in obese mice.

METHODS: In in vitro experiments, the effect of GEN(0, 0.1, 1, 10, 50 μmol/L) on the proliferation of mouse embryonic osteoblast precursor cells (MC3T3-E1) was determined by CCK 8. Alkaline phosphatase(ALP) staining and quantitative detection of ALP activity were performed to determine the changes of ALP activity in cells; RNA and protein expression levels of ALP, osteopontin (OPN) and osteocalcin (OCN) were detected by quantitative real-time PCR(qRT-PCR) and Western blot. Alizarin red staining was used to define the effect of GEN on mineralization of MC3T3-E1. To verify the feasibility of the PRF drug loading, the ultrastructure of PRF was subsequently observed under SEM. In in vivo experiments, obese C57 mouse models were established by high-fat diet feeding. On this basis, skull defect models with a diameter of 2.8 mm were established, and the prepared GEN/PRF complexes were placed into the bone defect area. The effects of GEN on skull defect repair in obese mice were evaluated by Micro-CT scanning and hematoxylin-eosin(H-E) staining. Statistical analysis was performed with GraphPad Prism 5.0 software package.

RESULTS: CCK 8 results showed that 0.1, 1 μmol/L GEN promoted cell proliferation within 7 days(P＜0.05); 10 μmol/L GEN had no significant effect on the process of cell proliferation. From the second day, 50 μmol/L GEN significantly inhibited cell growth and showed cytotoxicity(P＜0.05). These two concentrations had similar effects in promoting cellular osteogenic differentiation. SEM results showed that PRF presented a 3-dimensional network structure, providing space for loading drug molecules. In in vivo experiments, the body weight of mice in the high-fat diet (HFD) group was 27.7% greater than that in the normal diet group(P＜0.05) and had abnormal glucose tolerance (P＜0.05). Micro-CT showed that compared with the normal diet group, the number of bone trabeculae in the femur of obese mice was decreased(P＜0.05), the distance between bone trabeculae was widened(P＜0.05), and the bone density was decreased (P＜0.05). In addition, GEN (0.1, 1.0 μmol/L) loaded by PRF increased bone volume fraction in the skull of obese mice (P＜0.05). H-E results showed that GEN/PRF promoted the healing of the bone defects.

CONCLUSIONS: GEN promotes osteogenic differentiation of MC3T3-E1, and it can effectively accelerate the healing of cranial bone defects after loading with PRF in obese mice.

PMID:38583019

Shanghai Kou Qiang Yi Xue. 2024 Feb;33(1):6-12.

ABSTRACT

PURPOSE: Bioactive magnesium ions were successfully incorporated into the nanoporous titanium base coating by micro-arc oxidation(MAO), and its physical properties and osteogenic effects were explored.

METHODS: Non-magnesium-containing and magnesium-containing titanium porous titanium coatings(MAO, MAO-mg) were prepared by changing the composition of MAO electrolyte and controlling the doping of magnesium in porous titanium coatings. The samples were characterized by scanning electron microscope (SEM), roughness, contact angle and energy dispersive X-ray spectrometer (EDS). Mg²⁺ release ability of magnesium-doped nanoporous titanium coatings was determined by inductively coupled plasma/optical emission spectrometer(ICP-OES). The structure of the cytoskeleton was determined by live/dead double staining, CCK-8 detection of material proliferation-toxicity, and staining of β-actin using FITC-phalloidin. The effects of the coating on osteogenic differentiation in vitro were determined by alizarin red (ARS), alkaline phosphatase (ALP) staining and real-time polymerase chain reaction (qRT-PCR). SPSS 25.0 software package was used for statistical analysis.

RESULTS: The MAO electrolyte with magnesium ions did not change the surface characteristics of the porous titanium coating. Each group prepared by MAO had similar microporous structure(P＞0.05). There was no significant difference in surface roughness and contact angle between MAO treatment group (MAO, MAO-mg)(P＞0.05), but significantly higher than that of Ti group (P＜0.05). With the passage of cell culture time, MAO-mg group promoted cell proliferation (P＜0.05). MAO-mg group was significantly higher than other groups in ALP and ARS staining. The expression of Runx2 mRNA (P＜0.05), ALP(P＜0.05) and osteocalcin OCN(P＜0.05) in MAO-mg group was significantly higher than that in Ti and MAO groups.

CONCLUSIONS: MAO successfully prepared magnesium-containing nanoporous titanium coating, and showed a significant role in promoting osteogenic differentiation.

PMID:38583018

West Afr J Med. 2024 Feb 29;41(2):118-125.

ABSTRACT

BACKGROUND: Studies from different parts of the world on thyroid dysfunction have shown it to be widespread in patients with type 2 diabetes mellitus (T2DM); however, there is insufficient local data to support this observation.

AIM: To determine the burden of thyroid dysfunction among patients with T2DM at a Tertiary Hospital in Southeast Nigeria with emphasis on its prevalence and pattern of presentation.

METHODS: Four hundred and seventy-two subjects were recruited for the study. All the subjects (100%) were of African descent. Three hundred and fifty-four (354) of them were patients with T2DM, while 118 subjects who did not have T2DM served as the controls. This study is a descriptive cross-sectional study involving patients with type 2 diabetes mellitus attending the Diabetes Clinic or receiving treatment in the Medical Wards. Subjects were recruited using systematic sampling. The first patient was selected by simple random sampling, and subsequently, every consecutive subject was selected. Blood samples were tested for HbA1c, fT3, fT4, thyrotropin, and thyroid stimulating hormone. Socio-demographic information was retrieved from patient medical records. We used the Student’s t-test for statistical comparison of quantitative variables such as weight, height, blood pressure, serum TSH, and serum T3; while for comparison of proportions, we used a Chi-squared test. We set a p-value of less than 0.05 to be statistically significant.

RESULTS: Females formed the majority of the study population accounting for 56.5% of the type 2 DM patients and 62.7% of the controls. We observed that the mean age of the type 2 DM patients was 57.5 (±9.3) years, which was similar to the mean age of controls: 57.7±8.9 (p=0.17). We also observed that the mean age at diagnosis of DM was 54±7.6 years, while the mean duration of DM for all the type 2 DM patients was 6.5±2.8 years. We observed that in patients with T2DM, the prevalence of thyroid dysfunction was 12.4% and among the controls, a prevalence of 1.7% was observed (P <0.05). Females formed the majority (75%) of T2DM patients with thyroid dysfunction and hypothyroidism was the most common type of thyroid dysfunction (93.2%) observed in this study.

CONCLUSION: The prevalence of thyroid dysfunction in T2DM patients in this study was 12.4% which was high compared to 1.7% observed in the controls (P = 0.001). The majority of those who had thyroid dysfunction were females. About 9 in 10 of all subjects with thyroid dysfunction had hypothyroidism.

PMID:38581652

JAMA Cardiol. 2024 Apr 6. doi: 10.1001/jamacardio.2024.0873. Online ahead of print.

ABSTRACT

IMPORTANCE: The association between antibiotic prophylaxis and infective endocarditis after invasive dental procedures is still unclear. Indications for antibiotic prophylaxis were restricted by guidelines beginning in 2007.

OBJECTIVE: To systematically review and analyze existing evidence on the association between antibiotic prophylaxis and infective endocarditis following invasive dental procedures.

DATA SOURCES: PubMed, Cochrane-CENTRAL, Scopus, Web of Science, Proquest, Embase, Dentistry and Oral Sciences Source, and ClinicalTrials.gov were systematically searched from inception to May 2023.

STUDY SELECTION: Studies on the association between antibiotic prophylaxis and infective endocarditis following invasive dental procedures or time-trend analyses of infective endocarditis incidence before and after current antibiotic prophylaxis guidelines were included.

DATA EXTRACTION AND SYNTHESIS: Study quality was evaluated using structured tools. Data were extracted by independent observers. A pooled relative risk (RR) of developing infective endocarditis following invasive dental procedures in individuals who were receiving antibiotic prophylaxis vs those who were not was computed by random-effects meta-analysis.

MAIN OUTCOMES AND MEASURES: The outcome of interest was the incidence of infective endocarditis following invasive dental procedures in relation to antibiotic prophylaxis.

RESULTS: Of 11 217 records identified, 30 were included (1 152 345 infective endocarditis cases). Of them, 8 (including 12 substudies) were either case-control/crossover or cohort studies or self-controlled case series, while 22 were time-trend studies; all were of good quality. Eight of the 12 substudies with case-control/crossover, cohort, or self-controlled case series designs performed a formal statistical analysis; 5 supported a protective role of antibiotic prophylaxis, especially among individuals at high risk, while 3 did not. By meta-analysis, antibiotic prophylaxis was associated with a significantly lower risk of infective endocarditis after invasive dental procedures in individuals at high risk (pooled RR, 0.41; 95% CI, 0.29-0.57; P for heterogeneity = .51; I2, 0%). Nineteen of the 22 time-trend studies performed a formal pre-post statistical analysis; 9 found no significant changes in infective endocarditis incidence, 7 demonstrated a significant increase for the overall population or subpopulations (individuals at high and moderate risk, streptococcus-infective endocarditis, and viridans group streptococci-infective endocarditis), whereas 3 found a significant decrease for the overall population and among oral streptococcus-infective endocarditis.

CONCLUSIONS AND RELEVANCE: While results from time-trend studies were inconsistent, data from case-control/crossover, cohort, and self-controlled case series studies showed that use of antibiotic prophylaxis is associated with reduced risk of infective endocarditis following invasive dental procedures in individuals at high risk, while no association was proven for those at low/unknown risk, thereby supporting current American Heart Association and European Society of Cardiology recommendations. Currently, there is insufficient data to support any benefit of antibiotic prophylaxis in individuals at moderate risk.

PMID:38581643 | DOI:10.1001/jamacardio.2024.0873