Objective: To investigate the association between monocyte to high-density lipoprotein cholesterol ratio (MHR) and periodontitis and to provide new epidemiologic evidence on the factors affecting periodontitis. Methods: Data on MHR, periodontitis, and other covariates were selected from the NHANES(National Health and Nutrition Examination) database for 3 cycles of subjects in 2009-2010, 2011-2012, and 2013-2014, and a total of 8 456 study subjects were included. The study participants were grouped according to the prevalence of periodontitis (presence or absence), and three regression models (unadjusted covariates, partially adjusted covariates, and fully adjusted covariates) were constructed to analyze the relationship between MHR and periodontitis by using a weighted logistic regression method with stepwise adjustment for confounders. MHR was divided into four groups from Q1 to Q4 according to quartiles from small to large for weighted trend analysis, and the nonlinear relationship between MHR (continuous) and periodontitis was analyzed using a restricted cubic spline with subgroup analysis and sensitivity analysis. Results: All three logistic regression models showed a positive association between MHR and periodontitis (OR = 2.92, 95%CI: 2.14-3.99, P<0.001 (not adjusted); OR = 1.97, 95%CI: 1.39-2.78, P<0.001 (partially adjusted); OR = 1.62, 95%CI: 1.10-2.39, P = 0.017 (fully adjusted)). Trend analysis showed a significantly higher risk of developing periodontitis in the Q4 group compared with the Q1 group in both single (OR = 1.92, 95% CI: 1.58-2.33, P<0.001) and multifactorial analyses (OR = 1.30, 95% CI: 1.03-1.64, P = 0.029). Restricted cubic spline results did not support a nonlinear relationship between MHR and periodontitis (P for nonlinear>0.05), subgroup analysis showed no significant interaction between the covariates and MHR (P>0.05), and sensitivity analysis also showed a positive correlation between MHR and periodontitis (OR = 1.67, 95%CI: 1.31-2.14, P<0.001). Conclusion MHR is positively associated with the risk of developing periodontitis.

Objective: To explore the effect of different miniscrew placement heights on the distribution of biological forces produced by clear aligner combined with intramaxillary traction for mandibular molar distalization, to identify the miniscrew location that is conducive to the protection of lower anterior tooth anchorage and to provide a reference that can be used when designing clinical treatments. Methods: Mimics, GeomagicStudio 2017, SolidWorks 2016, and Ansys workbench were used to establish finite element analysis models and perform mechanical analysis under the following six working conditions: working condition 1 was the control group without miniscrews; working conditions 2 to 5 had miniscrew in the buccal bone cortex between the first and second molars of the lower jaw 10 mm, 7 mm, 4 mm, and 1 mm from the top of the alveolar crest, respectively; working condition 6 had the miniscrew in the center of the buccal tongue at the anterior edge of the ascending branch of the lower jaw 5 mm above the occlusal plane. Results: On the sagittal axis, miniscrew anchorage caused distal displacement of all teeth. Compared to the control group, in the miniscrew group, the displacement of the anterior molars exceeded that of the second molars. On the vertical axis, the result in the control group was similar to backward bending; the results in the miniscrew groups resembled the effect of a lever, lowering the lateral incisors and canines and raising the central incisors and first premolars. On the coronal axis, the second premolars and the first molars showed lingual displacement in the control group, and only the premolars and first molars showed lingual displacementin the miniscrew groups. The canines were the teeth that were most strongly affected by the change in miniscrew placement height. Conclusion The higher the miniscrew position is, the stronger the protective effect on the anterior anchorage. According to the miniscrew placement height, the mandibular arch should be properly narrowed, the central incisors and first premolars should be lowered, and the lateral incisors and canines should be raised when designing clinical treatments.

OBJECTIVE To establish a method for determining the blood concentration of apatinib and apply it clinically. METHODS Ultra-high performance liquid chromatography （UPLC） was used for the determination of blood concentration. The chromatographic column was ACQUITY UPLC BEH C18 with the mobile phase consisted of acetonitrile-0.1% formic acid aqueous solution （gradient elution） at the flow rate of 0.2 mL/min； the column temperature was 40 ℃， and the injection volume was 5 μL. The data of 26 cancer patients taking apatinib were collected， and their blood concentrations were measured. The correlation between patient’s blood concentration and age， dosage， adverse reactions， and combination therapy were analyzed； the levels of serum kidney injury-related factors [cystatin C （CysC）， kidney injury molecule 1 （KIM-1）， interleukin-18 （IL-18）， tumor necrosis factor-α （TNF-α）] were determined before and after treatment. RESULTS The linear range of apatinib was 500-2 000 ng/mL， with a precision RSD of 3.7%， stability RSD of 4.9%， and an average sample recovery rate of 96.0% （RSD was 2.1%）. The lowest blood concentration of apatinib was 103 ng/mL and the highest was 1 932 ng/mL among 26 patients. The blood concentration of apatinib in patients showed a fluctuating downward trend with age. At a dosage of 0.125 or 0.25 g， the blood concentration of patients taking apatinib was concentrated within the range of 1 000-2 000 ng/mL. Among 26 cancer patients， 13 experienced adverse reactions， and no adverse reaction was observed in those with blood concentrations ranging from 500 to ＜1 000 ng/mL. Twenty patients were simultaneously treated with other drugs，resulting in varying blood concentration. After treatment， the levels of serum CysC， KIM-1， IL-18 and TNF- α were significantly higher than before treatment （P＜0.05）. CONCLUSIONS The established UPLC method can quickly E-mail：duanxc@ahtcm.edu.cn detect the blood concentration of apatinib. When using apatinib in clinical practice， comprehensive consideration should be given to the patient’s age， drug combination， and the attention should be paid to preventing possible acute kidney damage caused by apatinib.

Objective To explore the effect of different miniscrew placement heights on the distribution of biologi-cal forces produced by clear aligner combined with intramaxillary traction for mandibular molar distalization,to identify the miniscrew location that is conducive to the protection of lower anterior tooth anchorage and to provide a reference that can be used when designing clinical treatments.Methods Mimics,GeomagicStudio 2017,SolidWorks 2016,and Ansys workbench were used to establish finite element analysis models and perform mechanical analysis under the fol-lowing six working conditions:working condition 1 was the control group without miniscrews;working conditions 2 to 5 had miniscrew in the buccal bone cortex between the first and second molars of the lower jaw 10 mm,7 mm,4 mm,and 1 mm from the top of the alveolar crest,respectively;working condition 6 had the miniscrew in the center of the buccal tongue at the anterior edge of the ascending branch of the lower jaw 5 mm above the occlusal plane.Results On the sagittal axis,miniscrew anchorage caused distal displacement of all teeth.Compared to the control group,in the miniscrew group,the displacement of the anterior molars exceeded that of the second molars.On the vertical axis,the result in the control group was similar to backward bending;the results in the miniscrew groups resembled the effect of a lever,lowering the lateral incisors and canines and raising the central incisors and first premolars.On the coronal ax-is,the second premolars and the first molars showed lingual displacement in the control group,and only the premolars and first molars showed lingual displacementin the miniscrew groups.The canines were the teeth that were most strong-ly affected by the change in miniscrew placement height.Conclusion The higher the miniscrew position is,the stron-ger the protective effect on the anterior anchorage.According to the miniscrew placement height,the mandibular arch should be properly narrowed,the central incisors and first premolars should be lowered,and the lateral incisors and ca-nines should be raised when designing clinical treatments.

Objective To explore the effect of different miniscrew placement heights on the distribution of biologi-cal forces produced by clear aligner combined with intramaxillary traction for mandibular molar distalization,to identify the miniscrew location that is conducive to the protection of lower anterior tooth anchorage and to provide a reference that can be used when designing clinical treatments.Methods Mimics,GeomagicStudio 2017,SolidWorks 2016,and Ansys workbench were used to establish finite element analysis models and perform mechanical analysis under the fol-lowing six working conditions:working condition 1 was the control group without miniscrews;working conditions 2 to 5 had miniscrew in the buccal bone cortex between the first and second molars of the lower jaw 10 mm,7 mm,4 mm,and 1 mm from the top of the alveolar crest,respectively;working condition 6 had the miniscrew in the center of the buccal tongue at the anterior edge of the ascending branch of the lower jaw 5 mm above the occlusal plane.Results On the sagittal axis,miniscrew anchorage caused distal displacement of all teeth.Compared to the control group,in the miniscrew group,the displacement of the anterior molars exceeded that of the second molars.On the vertical axis,the result in the control group was similar to backward bending;the results in the miniscrew groups resembled the effect of a lever,lowering the lateral incisors and canines and raising the central incisors and first premolars.On the coronal ax-is,the second premolars and the first molars showed lingual displacement in the control group,and only the premolars and first molars showed lingual displacementin the miniscrew groups.The canines were the teeth that were most strong-ly affected by the change in miniscrew placement height.Conclusion The higher the miniscrew position is,the stron-ger the protective effect on the anterior anchorage.According to the miniscrew placement height,the mandibular arch should be properly narrowed,the central incisors and first premolars should be lowered,and the lateral incisors and ca-nines should be raised when designing clinical treatments.

Objective To explore the effect of different miniscrew placement heights on the distribution of biologi-cal forces produced by clear aligner combined with intramaxillary traction for mandibular molar distalization,to identify the miniscrew location that is conducive to the protection of lower anterior tooth anchorage and to provide a reference that can be used when designing clinical treatments.Methods Mimics,GeomagicStudio 2017,SolidWorks 2016,and Ansys workbench were used to establish finite element analysis models and perform mechanical analysis under the fol-lowing six working conditions:working condition 1 was the control group without miniscrews;working conditions 2 to 5 had miniscrew in the buccal bone cortex between the first and second molars of the lower jaw 10 mm,7 mm,4 mm,and 1 mm from the top of the alveolar crest,respectively;working condition 6 had the miniscrew in the center of the buccal tongue at the anterior edge of the ascending branch of the lower jaw 5 mm above the occlusal plane.Results On the sagittal axis,miniscrew anchorage caused distal displacement of all teeth.Compared to the control group,in the miniscrew group,the displacement of the anterior molars exceeded that of the second molars.On the vertical axis,the result in the control group was similar to backward bending;the results in the miniscrew groups resembled the effect of a lever,lowering the lateral incisors and canines and raising the central incisors and first premolars.On the coronal ax-is,the second premolars and the first molars showed lingual displacement in the control group,and only the premolars and first molars showed lingual displacementin the miniscrew groups.The canines were the teeth that were most strong-ly affected by the change in miniscrew placement height.Conclusion The higher the miniscrew position is,the stron-ger the protective effect on the anterior anchorage.According to the miniscrew placement height,the mandibular arch should be properly narrowed,the central incisors and first premolars should be lowered,and the lateral incisors and ca-nines should be raised when designing clinical treatments.

Objective To explore the effect of different miniscrew placement heights on the distribution of biologi-cal forces produced by clear aligner combined with intramaxillary traction for mandibular molar distalization,to identify the miniscrew location that is conducive to the protection of lower anterior tooth anchorage and to provide a reference that can be used when designing clinical treatments.Methods Mimics,GeomagicStudio 2017,SolidWorks 2016,and Ansys workbench were used to establish finite element analysis models and perform mechanical analysis under the fol-lowing six working conditions:working condition 1 was the control group without miniscrews;working conditions 2 to 5 had miniscrew in the buccal bone cortex between the first and second molars of the lower jaw 10 mm,7 mm,4 mm,and 1 mm from the top of the alveolar crest,respectively;working condition 6 had the miniscrew in the center of the buccal tongue at the anterior edge of the ascending branch of the lower jaw 5 mm above the occlusal plane.Results On the sagittal axis,miniscrew anchorage caused distal displacement of all teeth.Compared to the control group,in the miniscrew group,the displacement of the anterior molars exceeded that of the second molars.On the vertical axis,the result in the control group was similar to backward bending;the results in the miniscrew groups resembled the effect of a lever,lowering the lateral incisors and canines and raising the central incisors and first premolars.On the coronal ax-is,the second premolars and the first molars showed lingual displacement in the control group,and only the premolars and first molars showed lingual displacementin the miniscrew groups.The canines were the teeth that were most strong-ly affected by the change in miniscrew placement height.Conclusion The higher the miniscrew position is,the stron-ger the protective effect on the anterior anchorage.According to the miniscrew placement height,the mandibular arch should be properly narrowed,the central incisors and first premolars should be lowered,and the lateral incisors and ca-nines should be raised when designing clinical treatments.

Objective To explore the effect of different miniscrew placement heights on the distribution of biologi-cal forces produced by clear aligner combined with intramaxillary traction for mandibular molar distalization,to identify the miniscrew location that is conducive to the protection of lower anterior tooth anchorage and to provide a reference that can be used when designing clinical treatments.Methods Mimics,GeomagicStudio 2017,SolidWorks 2016,and Ansys workbench were used to establish finite element analysis models and perform mechanical analysis under the fol-lowing six working conditions:working condition 1 was the control group without miniscrews;working conditions 2 to 5 had miniscrew in the buccal bone cortex between the first and second molars of the lower jaw 10 mm,7 mm,4 mm,and 1 mm from the top of the alveolar crest,respectively;working condition 6 had the miniscrew in the center of the buccal tongue at the anterior edge of the ascending branch of the lower jaw 5 mm above the occlusal plane.Results On the sagittal axis,miniscrew anchorage caused distal displacement of all teeth.Compared to the control group,in the miniscrew group,the displacement of the anterior molars exceeded that of the second molars.On the vertical axis,the result in the control group was similar to backward bending;the results in the miniscrew groups resembled the effect of a lever,lowering the lateral incisors and canines and raising the central incisors and first premolars.On the coronal ax-is,the second premolars and the first molars showed lingual displacement in the control group,and only the premolars and first molars showed lingual displacementin the miniscrew groups.The canines were the teeth that were most strong-ly affected by the change in miniscrew placement height.Conclusion The higher the miniscrew position is,the stron-ger the protective effect on the anterior anchorage.According to the miniscrew placement height,the mandibular arch should be properly narrowed,the central incisors and first premolars should be lowered,and the lateral incisors and ca-nines should be raised when designing clinical treatments.

Objective To explore the effect of different miniscrew placement heights on the distribution of biologi-cal forces produced by clear aligner combined with intramaxillary traction for mandibular molar distalization,to identify the miniscrew location that is conducive to the protection of lower anterior tooth anchorage and to provide a reference that can be used when designing clinical treatments.Methods Mimics,GeomagicStudio 2017,SolidWorks 2016,and Ansys workbench were used to establish finite element analysis models and perform mechanical analysis under the fol-lowing six working conditions:working condition 1 was the control group without miniscrews;working conditions 2 to 5 had miniscrew in the buccal bone cortex between the first and second molars of the lower jaw 10 mm,7 mm,4 mm,and 1 mm from the top of the alveolar crest,respectively;working condition 6 had the miniscrew in the center of the buccal tongue at the anterior edge of the ascending branch of the lower jaw 5 mm above the occlusal plane.Results On the sagittal axis,miniscrew anchorage caused distal displacement of all teeth.Compared to the control group,in the miniscrew group,the displacement of the anterior molars exceeded that of the second molars.On the vertical axis,the result in the control group was similar to backward bending;the results in the miniscrew groups resembled the effect of a lever,lowering the lateral incisors and canines and raising the central incisors and first premolars.On the coronal ax-is,the second premolars and the first molars showed lingual displacement in the control group,and only the premolars and first molars showed lingual displacementin the miniscrew groups.The canines were the teeth that were most strong-ly affected by the change in miniscrew placement height.Conclusion The higher the miniscrew position is,the stron-ger the protective effect on the anterior anchorage.According to the miniscrew placement height,the mandibular arch should be properly narrowed,the central incisors and first premolars should be lowered,and the lateral incisors and ca-nines should be raised when designing clinical treatments.

Objective To explore the effect of different miniscrew placement heights on the distribution of biologi-cal forces produced by clear aligner combined with intramaxillary traction for mandibular molar distalization,to identify the miniscrew location that is conducive to the protection of lower anterior tooth anchorage and to provide a reference that can be used when designing clinical treatments.Methods Mimics,GeomagicStudio 2017,SolidWorks 2016,and Ansys workbench were used to establish finite element analysis models and perform mechanical analysis under the fol-lowing six working conditions:working condition 1 was the control group without miniscrews;working conditions 2 to 5 had miniscrew in the buccal bone cortex between the first and second molars of the lower jaw 10 mm,7 mm,4 mm,and 1 mm from the top of the alveolar crest,respectively;working condition 6 had the miniscrew in the center of the buccal tongue at the anterior edge of the ascending branch of the lower jaw 5 mm above the occlusal plane.Results On the sagittal axis,miniscrew anchorage caused distal displacement of all teeth.Compared to the control group,in the miniscrew group,the displacement of the anterior molars exceeded that of the second molars.On the vertical axis,the result in the control group was similar to backward bending;the results in the miniscrew groups resembled the effect of a lever,lowering the lateral incisors and canines and raising the central incisors and first premolars.On the coronal ax-is,the second premolars and the first molars showed lingual displacement in the control group,and only the premolars and first molars showed lingual displacementin the miniscrew groups.The canines were the teeth that were most strong-ly affected by the change in miniscrew placement height.Conclusion The higher the miniscrew position is,the stron-ger the protective effect on the anterior anchorage.According to the miniscrew placement height,the mandibular arch should be properly narrowed,the central incisors and first premolars should be lowered,and the lateral incisors and ca-nines should be raised when designing clinical treatments.