Association of genetic polymorphisms of VAX1, MAFB, and NTN1 with nonsyndromic cleft lip with or without cleft palate in Chinese population.

Nonsyndromic cleft lip with or without palate (NSCL/P) is a common birth defect involving genetic factors. We conducted this case-control study to verify the association of ten single-nucleotide polymorphisms (SNPs) of six genes (VAX1, MAFB, PAX7, ABCA4, NTN1, and NOG) with NSCL/P in the Chinese population. The study included 249 NSCL/P patients, 62 nonsyndromic cleft palate only (NSCPO) patients and 480 controls. Three loci, namely, VAX1 rs7078160, MAFB rs11696257, and NTN1 rs4791774, were associated with NSCL/P (Bonferroni method adjusted p values were 0.020, 0.00031, and 0.030, respectively). We also found that the disease risk of individuals carrying both VAX1 rs7078160 and NTN1 rs4791774 was higher than those carrying only one of them (p = 4.50 × 10-4 and 6.03 × 10-3, respectively). SNPs of genes VAX1 rs7078160, MAFB rs11696257, and NTN1 rs4791774 increased NSCL/P risk in the Chinese population.

Assessment of Skeletal Maturation in Male Children With Unilateral Cleft Lip and Palate.

OBJECTIVES: To assess the skeletal maturation in male children with unilateral cleft lip and palate (UCLP) in comparison to that of noncleft peers using the cervical vertebral maturation (CVM) method. METHODS: A sample of 149 male UCLP patients aged from 8- to 16-year-old and 447 age-matched orthodontic individuals without clefts was retrospectively compiled. Cervical vertebral maturation was assessed based on the cephalometric radiographs. RESULTS: The proportion of children in CVMSI and CVMSII was higher in the UCLP group compared to that in the noncleft group, but there was no significant difference in the CVM stage of the cleft patients compared to their noncleft peers. In the 12- to 14-year-old group, children with UCLP showed significantly delayed skeletal maturity in comparison with their noncleft peers. No significant difference was found in the other 3 age groups. There was a statistically significant correlation between the skeletal age and chronological age in both the UCLP group and the noncleft group. There was no significant difference in the mean age at CVMII and CVMIII between the cleft patients and noncleft peers. CONCLUSIONS: Males with UCLP aged 12- to 14-year-old have a statistically significant increased risk of delayed skeletal maturity in comparison with their noncleft peers. The chronological age is not an accurate indicator to assess the degree of skeletal maturation.

Zygomaticomaxillary suture maturation evaluation in patients with and without cleft lip and palate.

INTRODUCTION: The zygomaticomaxillary suture (ZMS) maturation evaluation is a reliable method for predicting the optimal timing of maxillary protraction. The objective of this study was to compare age distribution patterns of ZMS maturation stages between cleft lip and palate (CLP) patients and non-cleft lip and palate (non-CLP) patients to aid our comprehension in choosing the optimal timing of maxillary protraction. METHODS: Samples of 216 non-CLP and 220 CLP Asian patients without orthodontic and orthognathic treatment aged 5-25 years were scanned to evaluate the ZMS maturation stage by 2 evaluators blindly. Evaluators' agreements and bilateral ZMS maturation consistency were assessed by weighted kappa tests. Age distribution patterns of each ZMS maturation stage were described. Gender effect and age distribution differences between groups were analyzed using an independent t-test. RESULTS: Evaluators' agreements and bilateral ZMS maturation consistency were satisfying (weighted kappa coefficient >0.90). At stages A and B, patients with CLP were 1.3 and 0.4 years older than patients in the non-CLP group (P <0.001 and P = 0.01). In contrast, at stage C, patients with CLP were approximately 1.2 years younger (P = 0.004). Gender barely played a role in the divergence of ZMS maturation (P >0.05). No statistically significant difference was observed between ZMS maturation of patients with unilateral or bilateral cleft lip and palate (UBCLP) and patients with unilateral or bilateral cleft lip (UBCL) (P >0.05). CONCLUSIONS: The ZMS development of patients with CLP was premature at stage C, whereas delayed at stages A and B.

Study on Tooth Movement After the Alveolar Bone Grafting in Patients With Unilateral Cleft Lip and Palate.

OBJECTIVES: The aim of the study was to explore the effectiveness of the cleft-adjacent teeth moved into the grafted alveolar bone in unilateral cleft lip and palate (UCLP) patients, and to evaluate the alveolar bone support of the teeth. METHODS: Twenty unilateral cleft lip and palate patients were recruited in this study. The average age was 12 years and 8 months. Periapical radiographs were taken for the cleft-adjacent teeth 3 months after bone grafting (T1) and after teeth moving into the grafted bone (T2), and for the contralateral teeth (T3) when teeth aligned. Alveolar bone support of the moved teeth and the contralateral teeth were measured using the ratio of bone support height to root length. Paired t test was performed for statistical analysis with SPSS17.0 software package. RESULTS: All the cleft-adjacent teeth were bodily moved into the grafted area. Average alveolar bone support ratio for the moved teeth was 86.48% (T1), 87.11% (T2), and 90.81% (T3) for the contralateral teeth. There was no statistically significant difference between T1 and T2 (P > 0.05). Although the contralateral teeth had the highest alveolar bone support ratio, significant differences were found between T3 and T2 (P < 0.05). CONCLUSIONS: Cleft-adjacent teeth could be bodily moved into the grafted bone from the iliac crest in UCLP patients. A successful level of alveolar bone support for the moved teeth was achieved. Moved-in teeth could be functionally loaded and may be benefit to the reduction of the resorption of grafted bone.

Biological Effects of Orthodontic Tooth Movement Into the Grafted Alveolar Cleft.

PURPOSE: Functional stimulus during orthodontic tooth movement into the grafted bone can lead to better alveolar bone grafting outcomes. The aim of this study was to analyze the biological effects of orthodontic tooth movement into the grafted alveolar cleft area with histologic staining, fluorescence staining, and real-time polymerase chain reaction (PCR). MATERIALS AND METHODS: An animal model of orthodontic tooth movement into the grafted alveolar cleft area was established in 8-week-old Sprague-Dawley rats. The animals were divided into the experimental group and the control group. Four checkpoints were observed: before orthodontic stimuli, day 1 after orthodontic stimuli, day 3 after orthodontic stimuli, and day 5 after orthodontic stimuli. The cleft bone formation conditions, including the collagen fibers and the activities of the osteoclasts and osteoblasts, were evaluated by histologic staining. The expression of tartrate-resistant acid phosphatase (TRAP), receptor activator nuclear factor κB ligand, and Runt-related transcription factor 2 was detected by real-time PCR in both groups. RESULTS: Hematoxylin-eosin staining showed that the remodeling process of iliac autografts was completed when the orthodontic stress was applied, whereas the bone tissues first showed osteoclastogenesis and then osteogenesis. On the basis of TRAP staining, the osteoclasts increased to the maximal amount on day 3 and decreased thereafter. Evidence from tetracycline fluorescence staining indicated that no obvious changes in osteoblast activity were detected at the early stage; however, it gradually increased, especially in the region close to the root surface. According to real-time PCR, the expression of TRAP increased in both the early and middle stages, that of receptor activator nuclear factor κB ligand increased in the early stage, and that of Runt-related transcription factor 2 increased in the late stage. Moreover, the results showed significant differences between the experimental and control groups. CONCLUSIONS: Orthodontic tooth movement into the alveolar cleft bone graft area promoted bone remodeling of embedded bone, thus inducing bone resorption and subsequent deposition.

Three-Year Follow-Up of a Patient With Unilateral Cleft Lip and Palate Treated With Maxillary Protraction and Alveolar Bone Grafting: An Approach Exploring the Potential Power of Growth.

Clinically, patients with operated unilateral cleft lip and palate always present with a concave profile, depressed midface, maxillary hypoplasia, narrow upper dental arch, and class III malocclusion. In this clinical report, the authors describe the successful orthodontic treatment of a patient with unilateral cleft lip and palate. A boy, 7 years 11 months of age, with a history of unilateral cleft lip and cleft palate presented with a Class I malocclusion on Skeletal Class III base. A satisfactory occlusion and a favorable lateral profile were achieved after maxillary protraction (face mask) combined with fixed appliance treatment, including alveolar bone grafting surgery. An acceptable occlusion and facial proportion were maintained after a 3-year retention period. These results suggest orthodontic treatment with growth interference is an effective option for a patient with cleft lip and palate.

Effects of Palate Repair on Cranial Base and Maxillary Morphology in Patients With Unilateral Complete Cleft Lip and Palate.

OBJECTIVE: To identify the effects of palate repair on cranial base and maxillary morphology in patients with unilateral cleft lip and palate (UCLP) and to discover the relevance between cranial base and maxilla through cephalometric analysis. DESIGN: Retrospective. PATIENTS: Thirty-seven UCLP patients with operated lip (OL) and unoperated palate constituted OL group and were classified into 5 cervical vertebral maturation (CVM) stages. Thirty-seven UCLP patients with operated lip and palate (OLP) and 37 noncleft people with skeletal class I malocclusion were CVM- and sex-matched with the OL group as OLP group and control group, respectively. CVM stage I and II were combined into group 1, CVM stage III to V were combined into group 2. INTERVENTIONS: Lateral cephalograms of all participants were obtained. MAIN OUTCOME MEASURES: Cephalometric analysis was employed, and data were compared among groups. RESULTS: Length of posterior cranial base (Ba-S) of the OL group was shorter than controls in group 1; Ba-S and the ratio between length of posterior and anterior cranial base (Ba-S/S-N) of the OL and OLP groups were smaller than controls in group 2. No significant differences in cranial base were found between the OL and OLP groups. In group 1, patients of the OLP group showed smaller SNA, ANS-Ptm, and ANS-Ptm/S-N, and patients of the OL group showed smaller ANS-Ptm. In group 2, both OL and OLP groups had smaller sella-nasion-A point angle (SNA), projection distance between ANS and Ptm points on FH plane (ANS-Ptm), and the ratio between ANS-Ptm and anterior cranial base length (ANS-Ptm/S-N). CONCLUSIONS: Palate repair seems to have no obvious effects on cranial base morphology in patients with UCLP. Those patients with lip operated, whether cleft palate operated or not, tend to have a smaller length of maxilla sagittally and this deformity progresses with age.

Asymmetric Dental Development Investigated by Cone-Beam Computed Tomography in Patients With Unilateral Cleft Lip and Alveolus.

OBJECTIVE: To investigate a possible delay in dental development of cleft-side teeth compared with the contralateral teeth in patients with unilateral cleft lip and alveolus with or without cleft palate (UCLA ± CP) and to correlate this delay to developmental stages of the corresponding teeth. DESIGN: Cross-sectional study. SETTING: Cleft Lip and Palate Care Center of Shanghai Ninth People's Hospital, Shanghai, China. PATIENTS: Forty Chinese patients with UCLA ± CP. MAIN OUTCOME MEASURE: Crown height (CH), root length (RL), and full length (FL) of permanent incisors, canines, premolars, and first molars were measured using cone-beam computed tomography and compared between cleft and noncleft sides. Discrepancies in tooth length between sides during different developmental stages of delayed teeth were also compared. RESULTS: There were no statistically significant differences in tooth length between sides in the mandible, except for RL of lateral incisors and RL and FL of the second premolars. In the maxilla, CH, RL and FL of cleft-side incisors, as well as RL and FL of cleft-side canines and first premolars, were all significantly shorter than those on the noncleft side (P < .05). The lateral incisors showed the highest reductions in RL and FL (47% and 29%). Moreover, reduction of RL of cleft-side maxillary central incisors was most evident in the early developmental stage (23%) and decreased with dental maturation (5%). CONCLUSIONS: Asymmetric dental development was presented in both jaws but mainly in maxillary anterior region. The RL deficiency of cleft-side central incisors differed at different developmental stages.

Establishment of a rat model for alveolar cleft with bone wax.

PURPOSE: Although treatment of cleft lip and cleft palate is becoming standardized, treatment of alveolar cleft remains controversial. Thus, preclinical animal work remains necessary to improve clinical outcome. This study established an alveolar cleft model in the rat. MATERIALS AND METHODS: Maxillary first molars were extracted to create a 4- × 4- × 3-mm complete alveolar cleft on the right and left sides in 25 8-week-old Sprague-Dawley rats. The left cleft was filled with bone wax and the right side remained untreated. Animals were sacrificed at 0, 4 and 8 weeks after surgery. Harvested alveolar cleft samples were evaluated by micro-computed tomographic and histologic analyses. RESULTS: The healing rate and osteoblast activity of the left cleft were less than those of the right cleft. CONCLUSION: This model of a critical-size alveolar cleft can be used efficiently for the therapeutic evaluation of novel techniques for the treatment of alveolar cleft.

An Animal Model for Inducing Deviation of the Mandible.

PURPOSE: Altering the occlusal surface is still a common choice for inducing a deviated mandible in an animal model. Botulinum neurotoxin type A (BoTx/A) can block the action potential transmission in neuromuscular junctions by inhibiting acetylcholine release without damaging the nerves and muscle structures. Our present study was aimed at developing an easy-to-reproduce animal model of asymmetric mandibles in which injection of BoTx/A was applied. MATERIALS AND METHODS: A total of 96 healthy 4-week-old male Sprague-Dawley rats were divided into 2 groups: an experimental group (n = 48) with BoTx/A injection and a control group (n = 48) with sterile saline injection at 4 sites of the right masseter muscle. Twelve rats from each group were humanely euthanized at weeks 1, 2, 3, and 4 for morphometric analysis using the micro-computed tomography (CT) findings. RESULTS: The micro-CT scans revealed facial asymmetry in the experimental group, with no facial asymmetry in the control group after injection. Significant differences were found between the experimental and control groups regarding the indexes containing the mandibular length (length from condyle to menton, length from coronoid to menton, and length of mandibular corpus from gonion to menton) and ramus height (posterior border and middle region near coronoid, and height of anterior mandible at vertical distance from menton). CONCLUSION: Our data have indicated that this deviated mandible animal model induced by injection of BoTx/A is highly reproducible and might be proved suitable for future studies of the asymmetric mandible.

Asymmetric maxillary protraction for unilateral cleft lip and palate patients using finite element analysis.

OBJECTIVE: Unilateral cleft lip and palate (UCLP) patients frequently present with an asymmetry in the nasomaxillary complex and a maxillary hypoplasia. The aim of this study was to investigate biomechanic effects of asymmetric maxillary protraction in UCLP patients using finite element method. METHODS: A finite element model of a UCLP patient's skull was generated using data from spiral computed tomographic scans. On the basis of this finite element model, three groups of orthopedic forces were loaded. All forces were applied in a direction that was 30 degrees downward and forward to the occlusal plane on the region of the alveolar of the maxillary canine. The value of orthopedic force was 5 N in cleft side and 5 N in noncleft side (group A), 6 N in cleft side and 5 N in noncleft side (group B), and 7 N in cleft side and 5 N in noncleft side (group C), respectively. RESULTS: All 3 groups were effective in promoting maxilla forward. In group B, the displacement difference between the cleft side and the noncleft side was the smallest. The largest value difference between the cleft side and the noncleft side was found in group C. CONCLUSIONS: Maxillary protraction with a loading of 6 N in the cleft side and 5 N in the noncleft side produced the most favorable outcome. It can be suggested that it might be advantageous to perform asymmetric maxillary protraction on UCLP patients.

Effects of lip repair on maxillofacial morphology in patients with unilateral cleft lip with or without cleft palate.

Objective : To evaluate the effects of lip repair on maxillofacial development of patients with unilateral cleft lip with or without cleft palate. Design : Retrospective. Patients : A total of 75 patients were recruited, including 38 surgical patients with complete unilateral cleft lip and alveolus and 37 patients with complete unilateral cleft lip and palate who had lip but not palate repair. As controls, 38 patients with no cleft were selected. All subjects were divided according to two growth stages: before the pubertal peak (GS1) and after the pubertal peak (GS2). Interventions : Lateral cephalograms of all subjects were obtained. Main Outcome Measures : Cephalograms were analyzed and compared in the study and control groups. Results : The patients with unilateral cleft lip and palate in both GS1 and GS2 demonstrated an almost normal maxillary and mandibular growth with retroclined maxillary incisors. The patients with unilateral cleft lip and palate showed a shorter length of maxilla, a more clockwise-rotated mandible, and retroclined maxillary incisors. Conclusions : There was an almost normal maxillary and mandibular growth but retroclined maxillary incisors in patients with cleft lip with or without cleft palate who had received lip repair only, indicating that lip repair may not have a negative impact on the maxillofacial development and influences only the inclination of the maxillary incisors. The shorter anterior-posterior maxillary length and larger gonial angle in patients with unilateral cleft lip and palate compared with those in patients with unilateral cleft lip and alveolus suggest that these variations in maxillary and mandibular growth may be a consequence of the cleft itself.

The association between interactive health literacy and dietary behaviors among Chinese college students: a large-scale cross-sectional study.

Background: The association between health literacy and healthy dietary behaviors has been explored in the European population. However, there is currently no evidence available specifically pertaining to Chinese college students particularly for interactive health literacy. Aims: The objective of this study was to investigate the association between interactive health literacy (IHL) and dietary behaviors in Chinese college students. Methods: This study included 11,856 Chinese college students (mean age = 18.8 years, SD = 1.2 years). We defined nine healthy dietary behaviors as consumption of water, egg, milk and milk products, vegetables, fruit, red meat, soy and soy products, seafood, and sugar-sweetened beverages. For each food group, participants who met the criterion for being a regular consumer of the item were assigned a score of 1, and otherwise were assigned a score of 0. Thus, the dietary behaviors score ranged from 0 to 9, with higher scores indicating healthier dietary behaviors. We used the revised 28-item Chinese Adolescent Interactive Health Literacy Questionnaire (CAIHLQ) to evaluate IHL; a higher score on this scale indicates a greater health literacy. Multivariate logistic regression was used to analyze the association between IHL level and frequency of different numbers of dietary behaviors. Results: After adjusting for sex, age, annual family income, place of residence, father's education level, and mother's education level, there was a clear and significant positive association between IHL and the likelihood of exhibiting diverse dietary behaviors. The adjusted odds ratio (95% CI) of exhibiting given nine dietary behaviors with reference to tertile 1 according to categories of IHL was as follows: 1.055 (0.694, 1.603) for tertile 2 and 1.849 (1.269, 2.696) for tertile 3 (p for trend = 0.001). Similarly, there are significant positive associations between IHL and the likelihood of exhibiting 2-8 dietary behaviors, except for exhibiting any one dietary behavior. We further found that, in addition to the health awareness factor, there were significant positive associations between physical activity and nutrition factors, and healthier dietary behaviors. Further, there was a significant negative association between interpersonal relationships and dietary behavior. Conclusion: The findings indicate a positive relationship between IHL and dietary behavior, such that the higher the level of IHL among college students, the healthier the dietary behavior they tend to adopt in their daily lives. These findings suggest the importance of developing stages of change-based educational interventions, which could help individuals with limited IHL to not only acquire necessary health-related knowledge but also to strengthen their motivation to engage in healthy dietary behaviors. Future studies should employ longitudinal prospective designs or randomized controlled trials to establish a causal association between IHL and healthy dietary behaviors.

Characterization and functional prediction of the dental plaque microbiome in patients with alveolar clefts.

Introduction: Alveolar cleft (AC) is a common congenital defect in people with cleft lip and palate (CLP). Alveolar bone grafting (ABG) is typically performed during adolescence, resulting in the fissure remaining in the mouth for a longer length of time. Patients with AC have a greater rate of oral diseases such as dental caries than the normal population, and the precise characteristics of the bacterial alterations caused by AC are unknown. Methods: We recruited a total of 87 subjects and collected dental plaque samples from AC adolescents (AAP), post-operative ABG adolescents (PAP), healthy control adolescents (CAP), AC young adults (AYP), post-operative ABG young adults (PYP), and healthy control young adults (CYP). The sequencing of 16S rRNA genes was performed. Results: The microbial composition of plaque from alveolar cleft patients differed significantly from age-matched healthy controls. Linear discriminant analysis effect size (LEfSe) analysis revealed that AAP was enriched for Neisseria, Haemophilus, Fusobacterium, Rhodococcus, Aggregatibacter, Gemella, and Porphyromonas, whereas AYP was enriched for Capnocytophaga, Rhodococcus, and Actinomyces-f0332. There were phenotypic differences in facultatively anaerobic, Gram-negative, Gram-positive, and oxidative stress tolerance between the AYP group with longer alveolar cleft and the healthy control group according to Bugbase phenotypic predictions. Alveolar bone grafting did not alter the functional phenotype of alveolar cleft patients but reduced the number of differential genera between alveolar cleft patients and healthy controls at both ages. Conclusions: Our study systematically characterized the supragingival plaque microbiota of alveolar cleft patients, post-alveolar bone grafting patients, and matched healthy controls in two ages to gain a better understanding of plaque ecology and microbiology associated with alveolar clefts.

Biomechanical effects on maxillary protraction of the craniofacial skeleton with cleft lip and palate after alveolar bone graft.

OBJECTIVE: To explore the biomechanical effects of maxillary protraction on the craniofacial skeleton in patients with unilateral cleft lip and palate (UCLP) after alveolar bone graft (ABG) and resorption of ABG, thus to provide theoretical basis for the clinical application of maxillary protraction, which can improve the facial deformity of the UCLP patients. METHODS: A finite element model of a UCLP patient's skull was generated using data from spiral computed tomographic (CT) scans. Based on this finite element model, another 6 ABG finite element models were constructed to simulate ABG and resorption of ABG, respectively (nonresorption model, upper one-third resorption of the grafted bone model, upper two-thirds resorption of the grafted bone model, lower one-third resorption of the grafted bone model, lower two-thirds resorption of the grafted bone model, upper one-third and lower one-third resorption of the grafted bone model). Two additional models were developed to simulate maxillary protraction with expansion and maxillary protraction alone. All models were loaded with orthopedic force (30 degrees downward and forward to the occlusal plane, 500 g per side) on the region of alveolar of maxillary canine. RESULTS: Before ABG, the cleft side showed larger displacement than the noncleft side, when it came to the stress distribution in the craniofacial suture, it showed an asymmetric pattern as well. After ABG, the displacement difference between the cleft side and the noncleft side decreased, and the stress distribution in the craniofacial suture showed more symmetric than that before ABG. The pterygopalatine suture obtained the largest value, followed by zygomaticotemporal, zygomaticomaxillary, and zygomaticofrontal sutures among the observed sutures. Higher stresses and pronounced forward displacement were generated in the craniofacial sutures after maxillary protraction with expansion. CONCLUSIONS: Maxillary protraction after ABG performed a more favorable outcome. Among the ABG models, nonresorption model showed the best effect after loading maxillary protraction force, and resorption in the lower region of the grafted bone showed a better effect than resorption in the upper region of the grafted bone. Maxillary expansion could effectively facilitate the orthopedic of the maxillary protraction presumably.

Association between gingival recession and proclination of maxillary central incisors near the cleft in patients with unilateral cleft lip and palate: A retrospective case-control study.

INTRODUCTION: The aim of this study was to investigate whether proclination of the maxillary central incisor near a cleft leads to gingival recession in patients born with unilateral cleft lip and palate. METHODS: Forty patients with unilateral cleft lip and palate were retrospectively enrolled. By using intraoral slides, casts, and cephalograms, changes in gingival recession and proclination were measured. The 2-sample t test, correlation, and stepwise logistic regression analyses were applied. RESULTS: There were statistically significant differences in proclination variations between subjects with and without increased gingival recession (P <0.0001). A positive correlation was shown between proclination and gingival recession. Bone grafting during treatment resulted in a significant difference in gingival recession (P <0.05). Every 2° of increase in the angle between the long axis of the maxillary central incisors and the sella-nasion plane had a 3.06 times greater risk for gingival recession (odds ratio, 3.06; 95% confidence interval, 1.329-7.046; P = 0.0086). CONCLUSIONS: Proclination of the maxillary central incisor adjacent to the cleft is positively correlated with gingival recession in patients with unilateral cleft lip and palate. Proclination should be limited to prevent gingival recession and its esthetic and functional problems. It is better for a borderline cleft patient to have orthognathic surgery rather than camouflage treatment. Bone grafting during treatment might benefit gingival recession. The angle between the long axis of the maxillary central incisors and the sella-nasion plane is considered the strongest predictor of gingival recession.

Zygomaticotemporal suture maturation evaluation in Chinese population using cone-beam computed tomography images.

Objective: This study aimed to evaluate the zygomaticotemporal suture (ZTS) maturation, analyze the age distribution patterns of ZTS maturation stages, and investigate the relationship between ZTS and cervical vertebral maturation (CVM). Methods: A total of 261 patients who underwent cone-beam computed tomography (112 males, mean age, 13.1 ± 3.3 years; 149 females, mean age, 13.7 ± 3.1 years) were examined to evaluate the ZTS stages. The ZTS stages were defined based on a modified method from previous studies on zygomaticomaxillary sutures. Differences between groups and correlations between indicators were analyzed using the Spearman correlation test, intraclass coefficient of correlation (ICC), one-way analysis of variance and rank sum test. Statistical significance was set at p < 0.05. The diagnostic value of CVM stages in identifying ZTS maturation stages was evaluated using positive likelihood ratios (LRs). Results: A positive relationship was found between the ZTS and CVM stage (r = 0.747, ICC = 0.621, p < 0.01) and between the ZTS stage and chronological age (r = 0.727, ICC = 0.330, p < 0.01). Positive LRs > 10 were found for several cervical stages (CSs), including CS1 and CS2 for the diagnosis of stage B, CS1 to CS3 for the diagnosis of stages B and C, and CS6 for the diagnosis of stages D and E. Conclusions: The ZTS maturation stage may be more relevant to the CVM stage than to the chronological age. The CVM stages can be good indicators for clinical decisions regarding maxillary protraction, except for CS4 and CS5.

A multi-level analysis on the causes of train-pedestrian collisions in Southwest China 2011-2020.

Collisions between trains and pedestrians are the primary cause of railway casualties. However, there remains a lack of comprehensive understanding regarding the underlying causes of this phenomenon. This study employs a multi-level approach to investigate the factors associated with the occurrence and severity of train-pedestrian collisions. The investigation is based on 2160 independent cases that occurred in southwest China from 2011 to 2020. Multiple contributing factors related to the victim, train, track, and socio-economic status of the surrounding district were examined, utilizing information from various sources. At the county level, several risk factors were identified in predicting the occurrence rate. These factors include higher population density and a greater number of normal-speed stations. However, the presence of high-speed train stations did not exhibit any significant impact. Additionally, the study found that regulations pertaining to protective fences were highly effective in reducing the occurrence rate. Regarding the prediction of collision severity, certain factors were found to increase the death rate. These factors include young men as victims, engaging in lying down or crossing behaviors, higher train speeds, gentle downhill slopes, lower education levels, and a higher proportion of the labor force. These findings emphasize the necessity of adopting a comprehensive perspective when examining the causes of train-pedestrian collisions. Furthermore, it underscores the significance of considering the notable differences between rapidly developing countries such as China and developed countries. Based on our findings, we also provide corresponding policy suggestions.

Sagittal maxillary growth pattern in unilateral cleft lip and palate patients with unrepaired cleft palate.

OBJECTIVE: The objective of the study was to examine the sagittal maxillary growth pattern during the mixed and permanent dentition in unilateral cleft lip and palate (UCLP) patients with unrepaired cleft palate. PATIENTS AND METHODS: A total of 30 nonsyndromic UCLP patients with unrepaired cleft palate were included, 15 of whom were in mixed dentition and 15 in permanent dentition.Cephalograms were analyzed and compared in the patients with UCLP who have operatively undergone repair with both the lip and palate as well as normal subjects. RESULTS: The UCLP patients with unrepaired cleft palate in mixed dentition showed decreased anterior-posterior length of the maxilla. The UCLP patients with unrepaired cleft palate in permanent dentition demonstrated an almost normal maxillary growth. The operated-on patients both in mixed and permanent dentitions showed maxillary retrusion as well as decreased maxillary length. CONCLUSIONS: There appears that there may be the potential normal maxillary growth in UCLP patients, and early surgical repair of the cleft palate may affect sagittal maxillary growth pattern in patients with cleft.

[Impact of maxillary sinus floor on the mesial movement of maxillary first molar].

PURPOSE: To investigate the impact of maxillary sinus floor on the mesial movement of maxillary first molar. METHODS: Orthodontic patients with maxillary first premolars extracted were selected. Their maxillary first molars were divided into case group and control group according to whether their roots were in contact with the maxillary sinus floor. The case group was further divided into three subtypes according to the depth of the root extruded into the maxillary sinus. A total of 64 maxillary first molars from 32 patients were enrolled in this study, including 34 in the case group (five in subtype Ⅱ, fourteen in subtype Ⅲ, and 15 in subtype Ⅳ) and 30 in the control group. The mesial movement distance of each root and crown and the inclination of each root long axis were measured, and resorption of each root was evaluated. SPSS 22.0 software package was used for data analysis. RESULTS: After orthodontic treatment, the mesial movement distance of roots from both groups were all lager than 2 mm. The mesial movement distance of the crown was not statistically different between the two groups (P＞0.05), while the mesial movement distance of the roots in the control group was significantly larger than in the case group（P＜0.05）. Inclined movement towards the mesial direction was found in both groups, and the inclination angle was significantly larger in the case group（P＜0.05）. The inclination angle of the first molars in the subtype Ⅳ was significantly larger than that in the subtype Ⅲ and the control group. Most of the maxillary first molars from both groups had no obvious root resorption（P＞0.05）. CONCLUSIONS: With the proper force system, maxillary first molars with roots extruded into the maxillary sinus floor can be moved mesialy with mild or no root resorption, while a larger inclination can be found compared with maxillary first molars without root extruding into the maxillary sinus floor. The deeper the root extruding into the maxillary sinus, the larger the inclination angle will be.