[Cone-beam CT analysis of vertical control of mandible and changes of temporomandibular joint in adult patients with skeletal class â ¡ malocclusion with high angle].

Objective: To investigate the shape and position changes of temporomandibular joint (TMJ) in adult skeletal class Ⅱ malocclusion with high angle patients after vertical mandibular control, and the correlation between vertical mandibular changes and condylar position changes. Methods: Twenty adult skeletal class Ⅱ malocclusion with high angle patients [6 males and 14 females, aged (21.4±2.4) years] who underwent extraction treatment and active vertical control in the Department of Orthodontics, Lanzhou University Stomatological Hospital from October 2017 to November 2020 were selected. Cone-beam CT data of the patient before and after treatment were imported into Invivo Dental 5.0 software for three-dimensional reconstruction and correction, and the vertical index of mandible in reconstructed lateral cephalogram (mandibular plane angle, posterior anterior height ratio, mandibular true rotation angle) were measured. Incisal angle and variables of condyle shape, position and articular fossa shape were measured. Paired t test was performed on the results before and after treatment, and the correlation between mandibular vertical changes and condylar position changes was determined by Pearson correlation coefficient calculation. Results: After treatment, the overbite and overjet were within normal range, and the vertical height of the molars was controlled. Compared with the measurement before treatment, mandibular plane angle and mandibular true rotation angle were decreased by 2.05°±1.22° (t=7.60, P<0.001) and 1.42°±1.92° (t=3.54, P=0.002), respectively. The posterior anterior height ratio was increased by (1.89±3.32)% (t=2.56, P=0.019). After treatment, the mediolateral diameter of condyle, the anteroposterior diameter of condyle, the maximum cross-sectional area of condyle, the height of condyle head, the width of articular fossa, the depth of articular fossa and the articular nodular angle were increased by (0.55±0.76) mm (t=-2.73, P=0.015), (0.27±3.51) mm (t=-3.23, P=0.006), (6.01±7.36) mm2 (t=-2.80, P=0.013), (0.33±0.72) mm (t=-2.14, P=0.046), (0.56±0.93) mm (t=-2.37, P=0.032), 0.33 (0.14, 0.51) mm (Z=-2.76, P=0.006) and 1.50°±2.40° (t=-2.44, P=0.028), respectively. The internal condylar space and the external condylar space were decreased by (0.33±0.49) mm (t=2.31, P=0.035) and (0.20±0.23) mm (t=3.58, P=0.003), respectively. Before orthodontic treatment, 6 patients were with anterior displacement of the condyle, 7 patients with central position of the condyle, and 7 patients with posterior displacement of the condyle. After correction, patients who were with central position of the condyle have not changed much. The posterior displaced condyle in 2 patients and anterior displaced condyle in 3 patients became in central position after treatment. The joint space index was closer to the central position in 3 patients with anterior displacement and 3 patients with posterior displacement. The position of condyle in 1 patient with posterior displacement and 1 patient with anterior displacement remained basically unchanged. There was a significant negative correlation between the change of the posterior-anterior height ratio and the change of the internal condylar space in patients (r=-0.52, P=0.019), and a low correlation with the contral condylar space and the external condylar space(r=-0.48, P=0.031; r=-0.47, P=0.035). Conclusions: Skeletal class Ⅱ malocclusion with high angle adult patients achieved normal overbite and overjet and remodeling of condyle and articular fossa occurred after orthodontic treatmnet and vertical control. There was a certain negative correlation between the change of posterior-anterior height ratio and the change of condylar position.

[Risk factors for the development of liver cancer in patients with hepatitis B-related liver cirrhosis treated with long-term nucleos(t)ide analogues].

Objective: To retrospectively analyze the risk factors for the development of liver cancer in patients with hepatitis B-related liver cirrhosis (LC) treated and fully managed with long-term nucleos(t)ide analogues (NAs). Methods: The study subjects were derived from the follow-up cohort of chronic hepatitis B and liver cirrhosis who received antiviral therapy in the Department of Infectious Diseases of the First Affiliated Hospital of Guangxi Medical University from February 2004 to September 2019. LC patients who met the inclusion criteria were enrolled. The life-table method was used to calculate the incidence of liver cancer. Multivariable Cox regression model was used to analyze the risk factors that may affect the development of liver cancer in patients with LC. A subgroup analysis was conducted in liver cirrhotic patients who developed liver cancer to evaluate the effectiveness of antiviral treatment compliance. The (2) test was used for rate comparison. Results: The median follow-up time of 198 LC cases treated with NAs was 6.0 years (1.0-15.3 years). By the end of the visit: (1) 16.2% (32/198) of LC patients had developed liver cancer, and the cumulative incidence of liver cancer in 1, 3, 5, 7, and 9 years were 0, 8.9%, 14.3%, 18.6%, and 23.4%, respectively, with an average annual incidence of 3.1%. Among the 32 cases with liver cancer, 68.7% had developed small liver cancer (22/32). (2) Univariate Cox model analysis showed that the development of liver cancer was related to four factors, i.e., the presence or absence of LC nodules, whether the baseline was first-line medication, the family history of liver cancer, and patient compliance. The results of multivariate Cox model analysis showed that poor patient compliance and baseline non-first-line medication were risk factors for liver cancer. (3) The results of log-rank test subgroup analysis showed that the 5-year cumulative incidence of liver cancer in patients with hardened nodules was significantly higher than that of patients without hardened nodules (21.7% vs. 11.5%, P = 0.029). The 5-year cumulative incidence of liver cancer in patients with non-first-line drugs was significantly higher than that of patients with first-line drugs (22.0% vs.8.2%, P = 0.003). The 5-year cumulative incidence of liver cancer in patients with poor compliance was significantly higher than that of patients with good compliance (21.3% vs. 12.7%, P = 0.014). The 5-year cumulative incidence of liver cancer in patients with a family history of liver cancer was significantly higher than that of patients without a family history of liver cancer (22.3% vs. 8.1%, P = 0.006). (4) Compared with patients with poor compliance, patients with good compliance had higher HBV DNA negative serconversion rate (98.7% vs. 87.8%, P = 0.005), and a lower virological breakthrough rate (12.1% vs. 29.3%, P = 0.007). Conclusion: The long-term NAs antiviral therapy can reduce the risk of liver cancer, but it cannot completely prevent the development of liver cancer, especially in patients with a family history of liver cancer and baseline hardened nodules (high risk of liver cancer). Furthermore, the complete management can improve patient compliance, ensure the efficacy of antiviral therapy, and reduce the risk of liver cancer development, so to achieve secondary prevention of liver cancer, i.e., early detection, diagnosis and treatment.

Coagulation characteristics of titanium (Ti) salt coagulant compared with aluminum (Al) and iron (Fe) salts.

In this study, the performance of titanium tetrachloride (TiCl(4)) coagulation and flocculation is compared with commonly used coagulants such as aluminum sulfate (Al(2)(SO(4))(3)), polyaluminum chloride (PACl), iron chloride (FeCl(3)), and polyferric sulfate (PFS) in terms of water quality parameters and floc properties. TiCl(4) flocculation achieved higher removal of UV(254) (98%), dissolved organic carbon (DOC) (84%) and turbidity (93%) than other conventional coagulants. Charge neutralization and physical entrapment of colloids within coagulant precipitates and adsorption, seemed to play a significant role during TiCl(4) flocculation, while the main mechanism for conventional coagulants was bridge-aggregation and adsorption. The aggregated flocs after TiCl(4) flocculation showed the fastest growth rate compared to the other coagulants, with the largest floc size (801 µm) occurring within 8 min. The floc strength factor of PACl, Al(2)(SO(4))(3), PFS, FeCl(3) and TiCl(4) was 34, 30, 29, 26 and 29, respectively, while the floc recovery factor of the TiCl(4) coagulant was the lowest. Based on the results of the above study, it is concluded that the TiCl(4) flocculation can reduce the hydraulic retention time of slow and rapid mixing, however, careful handling of sludge is required due to the low recoverability of the aggregated floc.