Effect of corticotomy techniques accelerating orthodontic tooth movement on root resorption / 北京大学学报(医学版)

In recent years, developing new methods to accelerate orthodontic tooth movement (OTM) has attracted extensive attention in the field of orthodontic clinical and scientific research. It reduces orthodontic treatment time and risks. Over the past, various approaches have been done to accelerate orthodontic tooth movement. Several forms of corticotomy techniques have been effective in inducing rapid tooth movement. These techniques activate regional acceleratory phenomenon and create a favorable microenvironment for accelerating tooth movement. Root resorption is one of most common side effects of orthodontic treatment. It affects the long-term viability and health of teeth. However, the effect of corticotomy techniques accelerating orthodontic tooth movement on root resorption still remains unclear. Accelerating tooth movement may have two-side effects on root resorption. Through shortening the treatment period and removing the hyalinized tissues, the acceleration of orthodontic tooth movement could reduce root resorption. The increase of root resorption might be due to the local inflammation and function of cementoclasts/odontoclasts. In this paper, we reviewed the effects of different corticotomy techniques accelerating orthodontic tooth movement on root resorption. Corticotomy techniques deal with mucoperio-steal flaps and bone tissues differently and develop towards minimally invasive. Previous studies on root resorption use two-dimensional images, including apical films and panoramic tomography, to evaluate the degree of root resorption. In recent years, researches measure the volume of root resorption accurately using cone-beam computed tomography (CBCT) and micro-CT. Most studies suggest that the root resorption during acceleration of orthodontic tooth movement through corticotomy techniques is not statistically different from that of traditional orthodontic treatment. Some studies using micro-CT have shown that the root resorption in the groups of corticotomy techniques increases compared with the control group without surgery. Because of the short duration of these studies, the clinical significance is controversial on the overall impact of corticotomy techniques on orthodontic treatment. Accelerating orthodontic tooth movement is still at its emerging phase and need further research in the form of clinical trials to illustrate the effect of corticotomy techniques accelerating orthodontic tooth movement on root resorption.

Chronic sleep deprivation exacerbates cognitive and pathological impairments in APP/PS1/tau triple transgenic Alzheimer's disease model mice / 生理学报

Sleep exerts important functions in the regulation of cognition and emotion. Recent studies have found that sleep disorder is one of the important risk factors for Alzheimer's disease (AD), but the effects of chronic sleep deprivation on the cognitive functions of AD model mice and its possible mechanism are still unclear. In the present study, 8-month-old male APP/PS1/tau triple transgenic AD model (3xTg-AD) mice and wild type (WT) mice (n = 8 for each group) were subjected to chronic sleep deprivation by using the modified multiple platform method, with 20 h of sleep deprivation each day for 21 days. Then, open field test, elevated plus maze test, sugar water preference test, object recognition test, Y maze test and conditioned fear memory test were performed to evaluate anxiety- and depression-like behaviors, and multiple cognitive functions. In addition, the immunohistochemistry technique was used to observe pathological characteristics in the hippocampus of mice. The results showed that: (1) Chronic sleep deprivation did not affect anxiety- (P = 0.539) and depression-like behaviors (P = 0.874) in 3xTg-AD mice; (2) Chronic sleep deprivation exacerbated the impairments of object recognition memory (P < 0.001), working memory (P = 0.002) and the conditioned fear memory (P = 0.039) in 3xTg-AD mice; (3) Chronic sleep deprivation increased amyloid β (Aβ) deposition (P < 0.001) and microglial activation (P < 0.001) in the hippocampus of 3xTg-AD mice, without inducing abnormal tau phosphorylation and neurofibrillary tangles. These results indicate that chronic sleep deprivation exacerbates the impairments of recognition memory, working memory and conditioned fear memory in 3xTg-AD mice by aggravating Aβ deposition and the excessive activation of microglia in the hippocampus.

Analysis of single-nucleotide polymorphism of Sonic hedgehog signaling pathway in non-syndromic cleft lip and/or palate in the Chinese population / 北京大学学报(医学版)

OBJECTIVE@#To study the relationship between Sonic hedgehog (Shh) associated single-nucleotide polymorphism (SNP) and non-syndromic cleft lip and/or palate (NSCL/P), and to explore the risk factors of cleft lip and/or palate. Many studies suggest that the pathogenesis of NSCL/P could be related to genes that control early development, in which the Shh signaling pathway plays an important role.@*METHODS@#Peripheral blood was collected from 197 individuals (100 patients with NSCL/P and 97 healthy controls). Haploview software was used for haplotype analysis and Tag SNP were selected, based on the population data of Han Chinese in Beijing of the international human genome haplotype mapping project. A total of 27 SNP were selected for the 4 candidate genes of SHH, PTCH1, SMO and GLI2 in the Shh signaling pathway. The genotypes of 27 SNP were detected and analyzed by Sequenom mass spectrometry. The data were analyzed by chi-squared test and an unconditional Logistic regression model.@*RESULTS@#The selected SNP basically covered the potential functional SNP of the target genes, and its minimum allele frequency (MAF) was >0.05: GLI2 73.5%, PTCH1 91.0%, SMO 100.0%, and SHH 75.0%. It was found that the genotype frequency of SNP (rs12674259) located in SMO gene and SNP (rs2066836) located in PTCH1 gene were significantly different between the NSCL/P group and the control group. Linkage disequilibrium was also found on 3 chromosomes (chromosomes 2, 7 and 9) where the 4 candidate genes were located. However, in the analysis of linkage imbalance haplotype, there was no significant difference between the disease group and the control group.@*CONCLUSION@#In China, NSCL/P is the most common congenital disease in orofacial region. However, as it is a multigenic disease and could be affected by multiple factors, such as the external environment, the etiology of NSCL/P has not been clearly defined. This study indicates that Shh signaling pathway is involved in the occurrence of NSCL/P, and some special SNP of key genes in this pathway are related to cleft lip and/or palate, which provides a new direction for the etiology research of NSCL/P and may provide help for the early screening and risk prediction of NSCL/P.

Novel Mutation of Cleidocranial Dysplasia-related Frameshift Runt-related Transcription Factor 2 in a Sporadic Chinese Case / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Cleidocranial dysplasia (CCD) is an autosomal dominant disease that affects the skeletal system. Common symptoms of CCD include hypoplasia or aplasia of the clavicles, delayed or even absent closure of the fontanels, midface hypoplasia, short stature, and delayed eruption of permanent and supernumerary teeth. Previous studies reported a connection between CCD and the haploinsufficiency of runt-related transcription factor 2 (RUNX2). Here, we report a sporadic Chinese case presenting typical symptoms of CCD.</p><p><b>METHODS</b>We made genetic testing on this sporadic Chinese case and identified a novel RUNX2 frameshift mutation: c.1111dupT. In situ immunofluorescence microscopy and osteocalcin promoter luciferase assay were performed to compare the functions of the RUNX2 mutation with those of wild-type RUNX2.</p><p><b>RESULTS</b>RUNX2 mutation was observed in the perinuclear region, cytoplasm, and nuclei. In contrast, wild-type RUNX2 was confined in the nuclei, which indicated that the subcellular compartmentalization of RUNX2 mutation was partially perturbed. The transactivation function on osteocalcin promoter of the RUNX2 mutation was obviously abrogated.</p><p><b>CONCLUSIONS</b>We identified a sporadic CCD patient carrying a novel insertion/frameshift mutation of RUNX2. This finding expanded our understanding of CCD-related phenotypes.</p>

Accuracy Assessment of Three-dimensional Surface Reconstructions of In vivo Teeth from Cone-beam Computed Tomography / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>The accuracy of three-dimensional (3D) reconstructions from cone-beam computed tomography (CBCT) has been particularly important in dentistry, which will affect the effectiveness of diagnosis, treatment plan, and outcome in clinical practice. The aims of this study were to assess the linear, volumetric, and geometric accuracy of 3D reconstructions from CBCT and to investigate the influence of voxel size and CBCT system on the reconstructions results.</p><p><b>METHODS</b>Fifty teeth from 18 orthodontic patients were assigned to three groups as NewTom VG 0.15 mm group (NewTom VG; voxel size: 0.15 mm; n = 17), NewTom VG 0.30 mm group (NewTom VG; voxel size: 0.30 mm; n = 16), and VATECH DCTPRO 0.30 mm group (VATECH DCTPRO; voxel size: 0.30 mm; n = 17). The 3D reconstruction models of the teeth were segmented from CBCT data manually using Mimics 18.0 (Materialise Dental, Leuven, Belgium), and the extracted teeth were scanned by 3Shape optical scanner (3Shape A/S, Denmark). Linear and volumetric deviations were separately assessed by comparing the length and volume of the 3D reconstruction model with physical measurement by paired t- test. Geometric deviations were assessed by the root mean square value of the imposed 3D reconstruction and optical models by one-sample t-test. To assess the influence of voxel size and CBCT system on 3D reconstruction, analysis of variance (ANOVA) was used (μ = 0.05).</p><p><b>RESULTS</b>The linear, volumetric, and geometric deviations were -0.03 ± 0.48 mm, -5.4 ± 2.8%, and 0.117 ± 0.018 mm for NewTom VG 0.15 mm group; -0.45 ± 0.42 mm, -4.5 ± 3.4%, and 0.116 ± 0.014 mm for NewTom VG 0.30 mm group; and -0.93 ± 0.40 mm, -4.8 ± 5.1%, and 0.194 ± 0.117 mm for VATECH DCTPRO 0.30 mm group, respectively. There were statistically significant differences between groups in terms of linear measurement (P < 0.001), but no significant difference in terms of volumetric measurement (P = 0.774). No statistically significant difference were found on geometric measurement between NewTom VG 0.15 mm and NewTom VG 0.30 mm groups (P = 0.999) while a significant difference was found between VATECH DCTPRO 0.30 mm and NewTom VG 0.30 mm groups (P = 0.006).</p><p><b>CONCLUSIONS</b>The 3D reconstruction from CBCT data can achieve a high linear, volumetric, and geometric accuracy. Increasing voxel resolution from 0.30 to 0.15 mm does not result in increased accuracy of 3D tooth reconstruction while different systems can affect the accuracy.</p>

A clinical study of invasive fungal disease in children without underlying diseases / 中国当代儿科杂志

<p><b>OBJECTIVE</b>To investigate the clinical features of invasive fungal disease (IFD) in children without underlying diseases.</p><p><b>METHODS</b>The clinical data of 49 children without underlying diseases who were diagnosed with IFD were retrospectively studied.</p><p><b>RESULTS</b>Fungal pathogens were detected in 37 (76%) out of 49 patients, including Cryptococcus neoformans (17 children, 46%), Candida albicans (10 children, 27%), Aspergillus (3 children, 8%), and Candida parapsilosis (3 children, 8%). Fungal pneumonia (17 children, 46%) was the most commonly seen disease, with Candida albicans as the major pathogen (9 children, 53%). The 49 children had at least one high-risk factor for infection, including the use of antibiotics, a long length of hospital stay, and invasive procedures. Of all the children, 82% did not respond well to antibiotic treatment or experienced recurrent pyrexia. Among the 24 children who underwent G tests, 17 (71%) showed positive results. All the children were given antifungal therapy, and among these children, 37 (75%)were cured, 3 (6%) were still in the treatment, 5 (10%) died, and 4 (8%) were lost to follow-up.</p><p><b>CONCLUSIONS</b>In IFD children without underlying diseases, Cryptococcus neoformans and Candida are the main pathogens, and lung infection is the most common disease. Long-term use of high-dose antibiotics may be an important risk factor for fungal infection. The IFD children without underlying diseases are sensitive to antifungal drugs and have a satisfactory prognosis.</p>

Reliability assessment and correlation analysis of evaluating orthodontic treatment outcome in Chinese patients / 国际口腔科学杂志·英文版

This study aimed to assess the reliability of experienced Chinese orthodontists in evaluating treatment outcome and to determine the correlations between three diagnostic information sources. Sixty-nine experienced Chinese orthodontic specialists each evaluated the outcome of orthodontic treatment of 108 Chinese patients. Three different information sources: study casts (SC), lateral cephalometric X-ray images (LX) and facial photographs (PH) were generated at the end of treatment for 108 patients selected randomly from six orthodontic treatment centers throughout China. Six different assessments of treatment outcome were made by each orthodontist using data from the three information sources separately and in combination. Each assessment included both ranking and grading for each patient. The rankings of each of the 69 judges for the 108 patients were correlated with the rankings of each of the other judges yielding 13 873 Spearman rs values, ranging from -0.08 to +0.85. Of these, 90% were greater than 0.4, showing moderate-to-high consistency among the 69 orthodontists. In the combined evaluations, study casts were the most significant predictive component (R(2)=0.86, P<0.000 1), while the inclusion of lateral cephalometric films and facial photographs also contributed to a more comprehensive assessment (R(2)=0.96, P<0.000 1). Grading scores for SC+LX and SC+PH were highly significantly correlated with those for SC+LX+PH (r(SC+LX)vs.(SC+LX+PH)=0.96, r(SC+PH)vs.(SC+LX+PH)=0.97), showing that either SC+LX or SC+PH is an excellent substitute for all three combined assessment.

Research on Chinese orthodontic specialists' subjective evaluation of orthodontic treatment outcome / 中华口腔医学杂志

<p><b>OBJECTIVE</b>To analyze the results of multiple Chinese orthodontic specialists' subjective evaluation of orthodontic treatment outcome, to investigate the relevance of different experiment items and to explore the weight of each monomial material.</p><p><b>METHODS</b>As a randomized clinical trial, with six orthodontic treatment centers and Angle's classification being regarded as two stratification factors, it contained 108 cases with integrity data, which was random extracted from 2383 cases that received orthodontic treatment in six orthodontic treatment centers during the past five years, gathering post-treatment study casts, cephalometrics and photographs of 48 cases as the research subject. Similarly taking Angle's classification as a stratification factor, 108 cases were randomly divided into 9 groups. The randomization of sampling and grouping were both generated by a pseudo-random number generator. According to the monomial and combined subjects, 69 orthodontic specialists were regarded as the raters to rank the 12 cases in each group, and to judge whether the case was qualified.</p><p><b>RESULTS</b>Correlation analysis: the Spearman r between Post-M + C and Post-M + C + P and the Spearman r between Post-M + P and Post-M + C + P were both greater than 0.950. The Spearman r between Post-M and Post-P and the Spearman r between Post-M and Post-C were about 0.300. The Spearman r between Post-P and Post-C was 0.505. Regression analysis: the linear regression results: M + C = 0.782M + 0.308C - 0.150, M + P = 0.804M + 0.233P - 0.091, M + C + P = 0.764M + 0.243P + 0.131C - 0.291. The r(2) of above three models was greater than 0.9.</p><p><b>CONCLUSIONS</b>It was applicable to use M + C and M + P instead of M + C + P. Study casts could not replace cephalometrics or photographs when doing subjective evaluation. Cephalometrics and photographs could not substitute for each other either. In the combined materials evaluation, model accounted for the largest percentage. Based on the regression model, for the greater part, the integration of several monomial materials could replace the combined material assessment effectively.</p>

Effect of maxillary protraction in patients with unilateral cleft lip and palate and anterior crossbite / 中华口腔医学杂志

<p><b>OBJECTIVE</b>To investigate the different changes after maxillary protraction between the cleft and non-cleft patients with anterior crossbite.</p><p><b>METHODS</b>Prospective controlled clinical trial was carried out. Eighteen patients (aged 9.6 +/- 1.2 years) with unilateral cleft lip and palate (UCLP) were chosen as the experimental group. Eighteen non-cleft patients (aged 9.8 +/- 1.4 years) with similar malocclusions were selected as control group. All the patients were before puberty according to the evaluation of the hand wrist radiograms. Hyrax appliance and reverse headgear were used in both experimental and control groups. Lateral cephalometric radiographs were taken before and after treatment. Computerized cephalometric analysis was carried out. Paired t tests or t test were performed using software package SAS 8.1.</p><p><b>RESULTS</b>After treatment, the main changes in experimental group were: SNA +1.45 degrees , A-TFH +2.19 mm, SNB -2.18 degrees , ANB +3.64 degrees , MP/SN +2.78 degrees , LL-EP +0.88 mm in UCLP group. And in control group were: SNA +1.42 degrees , A-TFH +2.12 mm, SNB -1.32 degrees , ANB +2.68 degrees , MP/SN +1.47 degrees , LL-EP -1.37 mm.</p><p><b>CONCLUSIONS</b>Before puberty, maxillary protraction could accelerate maxillary forward growth in UCLP patients and the changes were similar to non-cleft patients. The occlusal relationship and soft tissue profile were improved significantly in both patients with or without cleft. The amount of mandibular posterior rotation in patients with UCLP was larger than in those with no cleft.</p>

Orthodontic treatment of dental arch transverse disharmony in complete unilateral cleft lip and palate patients / 中华口腔医学杂志

<p><b>OBJECTIVE</b>To investigate the dental arch discrepancy in UCLP patients and the characteristics of orthodontic treatment of this kind of patients.</p><p><b>METHODS</b>48 Unilateral cleft lip and palate patients were examined clinically and dental arch transverse discrepancy were recorded. Treatment plan was made according to the maloccusion of each patient.</p><p><b>RESULTS</b>(1). Dental arch transverse discrepancy was seen in 60.4%, bilateral posterior crossbite in 33.3%, and unilateral posterior crossbite in 16.7% of patients with UCLP, respectively. (2). Serious crossbite was often seen in bicuspid region, so expansion in this area is the main task of orthodontic treatment. (3). Dental arch transverse discrepancy was usually mild in molar region. The upper molars were moved palatally in 10.4% of patients with UCLP.</p><p><b>CONCLUSIONS</b>Upper arch expansion is often needed in patients with UCLP, and the potential of dental arch expansion was large. The decision of upper tooth extraction in patients with moderate crowding should be made after dental arch expansion. Dental arch expansion should be done before alveolar bone grafting. Prolonged usage of the retainer is often needed.</p>