A structural equation modeling approach to determine the correlation between the vertical and sagittal skeletal patterns and posterior basal bones mismatching in patients with skeletal Class III malocclusion.

INTRODUCTION: Matching the maxillomandibular basal bone width is essential to the stability of orthodontic treatment. We aimed to determine the relationship between basal bone width mismatching and the vertical and sagittal skeletal pattern in patients with skeletal Class III malocclusion through shape analysis and structural equation modeling (SEM). METHODS: Cone-beam computed tomography images were collected from 45 men and 51 women. Width mismatching of the basal bone was determined using generalized Procrustes analysis. Twenty-two parameters from the synthesized cephalogram were measured, followed by factor analysis and SEM. RESULTS: Mismatch occurred at the second molar (men, -4.29 ± 4.32 mm; women, -5.55 ± 4.43 mm) and retromolar regions (men, -8.49 ± 5.11 mm; women: -8.93 ± 5.25 mm). The sum of angles had the largest loading for vertical-1 (extracted from 18 vertical cephalometric measurements) (men, 0.9477; women, 0.9489), followed by MP-SN angle (0.9408) in men and N-Me/S-Go (0.9342) in women. Wits appraisal and anteroposterior dysplasia indicator were largest for Sagittal-1. SEM showed a positive effect of male vertical-1 and 2 on width difference in the retromolar region (P <0.001; B >0). Female vertical-1 had a significant positive effect on DW7 (P <0.001; B = 5.535) and DWR (P = 0.016; B = 3.427) as vertical-2. Sagittal-1 showed a negative correlation with DW7 in both genders (P <0.05; B <0) and with DWR in men. CONCLUSIONS: Basal bone width mismatching occurred at the second molar and retromolar regions, especially in low-angle and patients with severe skeletal Class III malocclusion.

A comparative analysis of aerodynamic and anatomic characteristics of upper airway before and after mini-implant-assisted rapid maxillary expansion.

INTRODUCTION: The objective of this research was to observe changes in aerodynamics and anatomic characteristics of the upper airway after mini-implants assisted rapid maxillary expansion and to evaluate the correlation between the 2 changes of the upper airway in young adults. METHODS: Thirty consecutive patients (mean age, 23.82 ± 3.90 years; median, 24.5 years; 9 males, 21 females) were involved. Cone-beam computed tomography was taken before activation and over 3 months. Three-dimensional models of the upper airway were reconstructed on the basis of cone-beam computed tomography. The anatomic characteristics of the upper airway, including volume, area, transverse, and sagittal diameter, were measured. The aerodynamic characteristics of the upper airway were calculated on the basis of 3-dimensional models using computational fluid dynamics. The correlation between the changes in aerodynamics and anatomic characteristics of the upper airway was explored. RESULTS: The enlargements of the volume of the total pharynx, nasopharynx, and oropharynx were found (9.99%, 20.7%, and 8.84%, respectively). The minimum cross-sectional area increased significantly (13.6%). The airway resistance (R) and maximum velocity (Vmax) decreased significantly in both the inspiration and expiration phase (inspiration: R, -26.8%, Vmax, -15.7%; expiration: R, -24.7%, Vmax, -16.5%). The minimum wall shear stress reduced significantly only in the inspiration phase (-26.3%). The correlations between decreased R and increased volume and minimum cross-sectional area were observed. CONCLUSIONS: Mini-implants assisted rapid maxillary expansion is an effective device for improving anatomic characteristics represented by the total volume of the upper airway and minimum cross-sectional area, which contributed to the respiratory function depending on the favorable changes of aerodynamic characteristics including resistance, velocity, and minimum wall shear stress.

Skeletal width changes after mini-implant-assisted rapid maxillary expansion (MARME) in young adults.

OBJECTIVES: To observe skeletal width changes after mini-implant-assisted rapid maxillary expansion (MARME) and determine the possible factors that may affect the postexpansion changes using cone-beam computed tomography (CBCT) in young adults. MATERIALS AND METHODS: Thirty-one patients (mean age 22.14 ± 4.76 years) who were treated with MARME over 1 year were enrolled. Four mini-implants were inserted in the midpalatal region, and the number of activations ranged from 40 to 60 turns (0.13 per turn). CBCT was performed before MARME (T0), after activation (T1), and after 1 year of retention (T2). The mean period between T1 and T0 was 6 ± 1.9 months and between T2 and T1 was 13 ± 2.18 months. A paired t-test was performed to compare T0, T1, and T2. The correlations between the postexpansion changes and possible contributing factors were analyzed by Pearson correlation analysis. RESULTS: The widths increased significantly after T1. After T2, the palatal suture width decreased from 2.50 mm to 0.75 mm. From T1 to T2, decreases recorded among skeletal variables varied from 0.13 mm to 0.41 mm. This decrease accounted for 5.75% of the total expansion (2.26 mm) in nasal width (N-N) and 19.75% at the lateral pterygoid plate. A significant correlation was found between postexpansion change and palatal cortical bone thickness and inclination of the palatal plane (ANS-PNS/SN; P < .05). CONCLUSIONS: Expanded skeletal width was generally stable after MARME. However, some amount of relapse occurred over time. Patients with thicker cortical bone of the palate and/or flatter palatal planes seemed to demonstrate better stability.

Topiramate for hypoxic ischemic encephalopathy: A systematic review protocol.

BACKGROUND: Hypoxic ischemic encephalopathy (HIE) is brain injury caused by different reasons and the most common diagnosed is neonatal HIE. Most of the existing treatments have their own shortcomings or there are still some unexplained mechanisms in it. Topiramate (TPM) is a new drug for the treatment for seizures in neonates with HIE, but is currently used off-label. Our protocol aims to access the efficiency and safety of TPM for HIE. METHODS AND ANALYSIS: Eight databases will be searched by 2 independent researchers for the article on the topic of using TPM as treatment for HIE, including PubMed, the Cochrane Central Register of Controlled Trials (Cochrane Library), Embase, and Web of Science, China National Knowledge Infrastructure (CNKI), Chinese Biomedical Literature Database (CBM), Wang Fang Database and Chinese Science and Technology Periodical database (VIP). The included papers are those published from the established date of the databases to 2019. The therapeutic effects based on the grade of neonatal behavioral neurological assessment will be regarded as the primary outcomes. RevMan V5.3 will be used to compute the data synthesis and carry out meta-analysis. The risk of bias will be appraised by the Cochrane risk of bias tool. Rare ratio for dichotomous outcomes and mean different for continuous data will be expressed with 95% confidence intervals (CI) for analysis. A random effects model or a fixed effects model will be employed, when heterogeneity is found or not. Subgroup analysis and sensitivity analysis will be applied if the heterogeneity is obvious. RESULTS: This study will provide the recent evidence of TPM for HIE from reducing seizure acticity. CONCLUSION: The conclusion of this study will provide proof to evaluate if TPM is effective and safe in the treatment of HIE.PROSPERO registration number: PROSPERO CRD42018117981.

Guizhi Gancao Longgu Muli decoction for insomnia: A protocol for a systematic review.

BACKGROUND: Insomnia is a prevalent and bothersome disorder of sleep initiation and maintenance. Although efficacious treatments for insomnia have been available for decades, they all have their own limitations. Guizhi Gancao Longgu Muli Decoction (GGLMD), a popular complementary and alternative therapy, has been widely applied to treat insomnia in some Asian countries for centuries. Yet no systematic reviews have comprehensively assessed the efficacy and safety of GGLMD as a treatment for insomnia. METHODS: A comprehensive search up to November, 2019 will be conducted in the following electronic databases: the Cochrane Library, Embase, PubMed, Web of Science, the Chinese National Knowledge Infrastructure (CNKI), the Chinese Biomedical Literature Database (CBM), the Chinese Scientific Journal Database (VIP), and the Wanfang Database. The primary outcomes will be sleep quality including Pittsburgh Sleep Quality Index (PSQI) and polysomnography (PSG). Stata 15 will be used for data analysis as well. RESULTS: This study will provide the current evidence of insomnia treated with GGLMD from the several points including PSQI and PSG. CONCLUSION: The consequence of this summary will furnish proof to evaluate if GGLMD is effective in the treatment of insomnia. ETHICS AND DISSEMINATION: Without personal information involved, ethical approval and informed consent form is no need. The review will be submitted to a peer-reviewed journal prospectively to spread our findings. PROSPERO REGISTRATION NUMBER: PROSPERO CRD42018118336.