Improved super-elastic Ti-Ni alloy wire for treating adult skeletal class III with facial asymmetry:A case report

BACKGROUND Correcting severe skeletal class III malocclusion with facial asymmetry in adults through orthodontic treatment alone is difficult.CASE SUMMARY In this case report,we describe orthodontic treatment and lower incisor extraction without orthognathic surgery for a 27-year-old man with a transverse discrepancy.The extraction sites were closed using an elastic chain.The use of intermaxillary elastics,improved super-elastic Ti-Ni alloy wire,and unilateral multibend edgewise arch wire was crucial for correcting facial asymmetry and the midline deviation.CONCLUSION After treatment,the patient had a more symmetrical facial appearance,acceptable overjet and overbite,and midline coincidence.The treatment results remained stable 3 years after treatment.This case report demonstrates that a minimally invasive treatment can successfully correct severe skeletal class III malocclusion with facial asymmetry.

Prevalence of angle class III malocclusion: A systematic review and meta-analysis

Objective: This study seeks to review current and relevant literature on global Angle class III malocclusion prevalence. Materials and Methods: The electronic databases PubMed, ISI Web of Knowledge, and the Cochrane Database of Systematic Review were searched using specific inclusion criteria to obtain applicable articles. All pertinent references were also examined for acceptability. Results: A total of 20 articles were identified using the inclusion criteria. The prevalence of Angle class III malocclusion ranged from 0 to 26.7% in different populations reported in the literature examined. Meta-regression analysis showed no statistically significant association between prevalence rates and the method of assessment, age group and year of the study. However, much of the study-to-study variation (approximately 40%) could be explained by population. Conclusion: These results suggest that the prevalence of Angle class III malocclusion varies greatly within different races and geographic regions. Chinese and Malaysian populations have a higher prevalence of Angle class III malocclusion compared to other racial groups, while Indian populations have a lower prevalence than all other racial groups examined.

Orthodontic camouflage versus orthognathic surgery: A comparative analysis of long-term stability and satisfaction in moderate skeletal Class III

Objective: The purpose of this study was to compare long-term stability and satisfaction between orthodontic camouflage and orthognathic surgery in treatment of moderate skeletal Class III adults. Materials and Methods: A total of 25 adults females who had been treated with orthodontic camouflage for Class III malocclusions were recalled at least 3 years post-treatment to evaluate stability and satisfaction with treatment outcomes. The data were compared with similar data for long-term outcomes in 21 patients with the same Class III problems who had bimaxillary surgical correction. Results: In the camouflage patients, small mean changes in skeletal landmark positions occurred over the long term, although the changes were generally much smaller than in the surgery patients. Dental changes in the surgery group were more severe than those in the camouflage group. The camouflage patients reported fewer functional or temporomandibular joint problems than did the surgery patients. Both groups reported similar levels of overall satisfaction with treatment. Conclusion: The results suggest that both camouflage and surgical treatment in moderate skeletal Class III adults can achieve satisfactory outcomes and provide long-term stability. If patients do not readily accept surgery because of potential surgical complications or financial difficulties, camouflage treatment may be an effective alternative treatment.

Non-Surgical Orthodontic Treatment of Class III Adult with Posterior Crossbite, Anterior Open Bite and Asymmetric Occlusion, Using TADs and Auxiliary Wires: A Case Report

Class III malocclusion associated with posterior crossbite, anterior open bite pattern with asymmetric occlusion in adults can be a challenging orthodontic problem, especially for the nonsurgical treatment. Skeletal Class III anteroposterior discrepancies in adult patients are generally managed either by surgical-orthodontic treatment or by orthodontic camouflage through dentoalveolar compensation. Although correction with surgery may be the most effective and stable way, many patients refuse surgical treatment plan because of the costs and traumas it may bring. This case report describes the successful use of TADs with expansion auxiliary wire to treat a 24-year-old man with skeletal class III malocclusion, posterior crossbite, anterior open-bite and asymmetric occlusion, mild upper and lower dental spacing and a chief manifestation of anterior crossbite. The patient refused surgery. A treatment plan was formulated consisting of using auxiliary expansion wire to expand the maxillary arch, 8 mm mini-screws between the roots of the mandibular canines and first premolars, preadjusted edgewise brackets to align the teeth, Class III and asymmetric elastics to correct the canines, premolars, and molars relationship and midline deviation, reverse curve of the nickel-titanium wire combined with anterior vertical elastics to intrude molars and correct the anterior open-bite. In this case, without going through surgery, the posterior cross-bite was corrected, and ideal overjet and overbite relationships, midline coincidence and functional occlusion were all achieved. Satisfactory occlusal, functional, esthetic and stable results were obtained.

Orthopedic Correction of Class III Malocclusions during Mixed Dentition

Objective: The aim of this study was to compare the effect of face mask (FM) and Maxillary Bite Block (BB) in skeletal class III patients during mixed dentition with control group of the same class during their growth. Materials & Methods: Forty-two patients were selected based on clinical and cephalometric examination, with age ranged from 6 to 8 years according to definite criteria. Patients were classified into two groups: treated and control groups;all records were taken for every patient. Lateral cephalometric films were traced before and after treatment and analyzed. Results: Intermaxillary skeletal variables showed significant improvement in the treated group with an average increase of ANB angle (Maxilo mandibular difference angle) of 3.14°and an average increase in wits appraisal 2.15 mm. Conclusion: The study concluded that, treatment with face mask and maxillary bite block induced significant dentoskeletal changes.

Surgical Manipulation of the Occlusal Plane in Class III Deformities: 5 Features to Help Planning

Class III malocclusion is one of the most common deformities that requires correction through orthodontic-surgical treatment. These patients present different facial patterns depending on the occlusal plane angulation. These patients may benefit from surgical manipulation of the occlusal plane, because only bite correction does not always lead to the improvement of the facial deformity. The purpose of this paper is to show the surgical manipulation of the occlusal plane in Class III patients based on five features: 1) facial type, 2) upper incisor display at rest, 3) dental exposure during smile, 4) soft tissue support, and 5) chin projection. The surgical manipulation of the occlusal plane can improve the esthetic outcome in the treatment of class III deformities, and careful evaluation of the five features described could be a helpful planning method.

Pseudo class III treatment in 2-year-old children

Timing of orthodontic treatment especially for children with developing Class III malocclusions has always been somewhat controversial. Pseudo class III malocclusion is recommended to be treated early as this type of malocclusion doesn’t diminish with age. Untreated pseudo class III may lead to serious problems. The case report describes pseudo class III in primary dentition successfully treated by using Protrusive Arch Wire.

Nonsurgical orthodontic treatment for an adult with skeletal open bite, class III malocclusion and posterior crossbite: A case report

Class III malocclusion associated with skeletal anterior open bite pattern in adults can be a challenging orthodontic problem, especially for the nonsurgical treatment. Conventionally, several treatment alternatives are available such as tooth extraction, molar intrusion, and absolute anchorage system or orthognathic surgical correction. Although correction with surgery may be the most effective and stable way, many patients refused surgical treatment plan because of the costs and traumas it may bring. We reported a nonsurgical orthopedic treatment of 22-year-old male with severe skeletal anterior open bite, dental Class III malocclusion, posterior crossbite and a high mandibular plane angle. The patient refused surgery and extraction. So we formulated a treatment plan consisting of using rapid palatal expansion appliance to expand the maxilla, standard edgewise brackets to align the teeth, Class III elastics to correct the canines, premolars, and molars relationship, reverse curve of the nickel-titanium wire combined with anterior vertical elastics to intrude molars and correct open bite. In this case, without suffering of surgery, the posterior crossbite was ideally corrected, and ideal overjet and overbite relationships and functional occlusion were all achieved. The patient obtained satisfactory occlusal as well as functional and stable results.

Endoscopic sleeve gastroplasty in class Ⅲ obesity:Efficacy, safety, and durability outcomes in 404 consecutive patients

BACKGROUND Endoscopic sleeve gastroplasty(ESG) is an effective therapy for class Ⅰ-Ⅱ obesity, but there are knowledge gaps in the published literature about its implementation in patients with class Ⅲ obesity [body mass index(BMI) ≥ 40 kg/m2].AIM To evaluate the safety, clinical efficacy, and durability of ESG in adults with class Ⅲ obesity.METHODS This was a retrospective cohort study that used prospectively collected data on adults with BMI ≥ 40 kg/m2who underwent ESG and longitudinal lifestyle counseling at two centers with expertise in endobariatric therapies from May 2018-March 2022. The primary outcome was total body weight loss(TBWL) at 12 mo. Secondary outcomes included changes in TBWL, excess weight loss(EWL) and BMI at various time points up to 36 mo, clinical responder rates at 12 and 24 mo, and comorbidity improvement. Safety outcomes were reported through the study duration. One-way ANOVA test was performed with multiple Tukey pairwise comparisons for TBWL, EWL, and BMI over the study duration.RESULTS 404 consecutive patients(78.5% female, mean age 42.9 years, mean BMI 44.8 ± 4.7 kg/m2) were enrolled. ESGs were performed using an average of 7 sutures, over 42 ± 9 min, and with 100% technical success. TBWL was 20.9 ± 6.2% at 12 mo, 20.5 ± 6.9% at 24 mo, and 20.3 ± 9.5% at 36 mo. EWL was 49.6 ± 15.1% at 12 mo, 49.4 ± 16.7% at 24 mo, and 47.1 ± 23.5% at 36 mo. There was no difference in TBWL at 12, 15, 24, and 36 mo from ESG. TBWL exceeding 10%, 15%, and 20% was achieved by 96.7%, 87.4%, and 55.6% of the cohort at 12 mo, respectively. Of the cohort with the relevant comorbidity at time of ESG, 66.1% had improvement in hypertension, 61.7% had improvement in type Ⅱ diabetes, and 45.1% had improvement in hyperlipidemia over study duration. There was one instance of dehydration requiring hospitalization(0.2% serious adverse event rate).CONCLUSION When combined with longitudinal nutritional support, ESG induces effective and durable weight loss in adults with class Ⅲ obesity, with improvement in comorbidities and an acceptable safety profile.

骨性III类错牙合畸形患者正颌手术前后咀嚼肌功能变化的初步研究

目的:应用肌电图仪评价骨性III类错牙合畸形患者正颌手术前后咀嚼肌功能的变化。方法:收集16例骨性III类错牙合畸形需正颌手术病例和20例正常牙合对照组,应用MedelecSynergy肌电图仪分别在静息放松、正中紧咬、前伸、开口、侧方和咀嚼运动时,测定双侧颞肌前束、咬肌和二腹肌前腹的表面募集电位,并计算其肌不对称指数运动。病例组在术后3个月和6个月时重复测定,采用t检验进行统计学分析,并与对照组进行比较。结果:手术前病例组咀嚼肌电位小于对照组,尤以紧咬和咀嚼时差异显著(P<0.05),肌不对称指数与对照组无差异。术后3个月时,部分肌功能恢复,但紧咬和咀嚼时募集电位下降显著(P<0.001),肌不对称指数也增大,提示此时肌功能尚未完全恢复。术后6个月各种功能运动时的募集电位均大于术前水平,肌不对称指数则基本小于术前水平,说明肌功能有所改善。结论:骨性III类错牙合畸形患者手术前咀嚼肌功能弱于对照组,正颌手术矫正了颌骨位置和咬合关系,改善了患者的咀嚼肌功能。

骨性III类错畸形患者正颌手术前后力变化的初步研究

目的:应用计算机咬合分析系统,评价正颌手术前后骨性III类错牙合患者牙合力的变化。方法:收集15例骨性III类错牙合需正颌手术病例,利用T-ScanII牙合诊断分析系统在术前1周内、术后3个月和术后6个月时对患者的牙合力进行测定,分析患者的总牙合力(TOF)、MIP/MAX指数、牙合力不对称指数(AOF)、牙合力中心点位置(COF)及咀嚼时最大位移距离(MCOF),应用配对t检验进行比较研究。结果:术后3个月时TOF有所上升,6个月时与术前水平相比已有显著差异(P<0.05),说明患者牙合力水平已有提高。MIP/MAX指数略有下降,但6个月时增大并超过术前水平。AOF术后呈下降趋势,在3个月和6个月时均比术前显著减小(P<0.01,P<0.001)。术后COF逐渐接近正常,MCOF减小,术后6个月时均较术前明显改善,说明患者牙合力水平已有提高。结论:正颌正畸联合治疗能够改善骨性III类错牙合患者的牙合力水平及力平衡性。

防爆电气CCC认证领域分析研究

自2019年10月1日起,防爆电气产品纳入强制性产品认证管理范围,由指定认证机构开始受理相关委托。本文从认证机构角度,选取强制性产品认证指定认证机构中创新海(天津)认证服务有限公司,对2021年度Ⅱ类、Ⅲ类防爆电气认证领域受理数据进行汇总。从17类防爆电气产品受理类型、数量、各月变化趋势,以及涉及的地区数据进行图表分析,得出防爆电气产品申请数量、种类有较多影响因素。为防爆电气各方进行CCC认证提供参考借鉴。

骨性III类错畸形患者正颌手术前后下颌运动轨迹变化的初步研究

目的:应用下颌运动轨迹仪评价骨性III类错牙合畸形患者正颌手术前后下颌运动的变化。方法:对15例骨性III类错牙合畸形需正颌手术病例和20例正常牙合对照组,采用ARCUSDigma下颌运动轨迹仪测定受试者最大开口运动,前伸及左右侧边缘运动距离,记录由计算机通过切牙运动模拟的双侧髁突的运动轨迹间的最大差数(MRC)。通过自身比较以及与对照组比较,评价患者在术前、术后3个月及6个月时下颌运动的变化以及髁突运动的对称性。采用团体t检验和配对t检验进行统计学处理。结果:术前患者除开口度外,其他运动距离均小于对照组,前伸运动差异显著(P<0.05);开口时MRC值大于对照组(P<0.05)。术后3个月时,开口度及左侧运动距离下降,前伸和右侧运动略有增加;MRC呈上升趋势。术后6个月时,下颌运动距离均有所增加,除开口度外其余均超过术前水平,与对照组无统计学差异;MRC小于术前水平且与对照组差异无显著性。结论:骨性III类错牙合畸形患者下颌运动水平与正常牙合存在差异,髁突运动对称性较差。正颌手术能够有效地改善患者的下颌运动功能。

Damon自锁矫治器在安氏III类错牙合不拔牙矫治中的应用

目的探讨Damon MX自锁托槽矫治器在安氏III类错牙合不拔牙矫治中的应用。方法选取安氏Ⅲ类错牙合患者26例,均采用Damon MX自锁托槽矫治器进行不拔牙矫治,并于矫治前后进行头影测量分析,比较患者矫治前后上下颌骨、切牙及面部软组织变化情况。结果矫治后,SNA、ANB、U1-L1、U1-NA距及Ls-E距均较矫治前增大(P<0.05或P<0.01),U1-SN、U1-NA、L1-MP及L1-NB均较矫治前减少(P<0.05或P<0.01)。结论使用Damon MX自锁托槽矫治安氏Ⅲ类错牙合,可有效控制上切牙根唇向转矩,减少上切牙唇倾度,改善患者面部软组织侧貌美观。

应用改良式Andresen矫治器治疗安氏III类错

目的 探讨治疗安氏III类错牙合的有效途径。方法 36例临床诊断为功能性安氏III类错牙合的患者 ,其中男 2 0例 ,女 16例。应用改良式Andresen矫治器进行治疗。结果 36例患者反牙合均解除 ,面型得到改善。结论 在适应症范围内 ,改良式Andresen矫治器治疗功能性安氏III类错牙合效果肯定 ,值得推广与应用。

双向链路下IEEE802.16e中节能类型III的性能分析

为了有效地节省移动终端(mobile station,MS)的能量消耗,延长无线城域网中MS的生命期,综合考虑了IEEE 802.16e节能类型III的双向链路,将上行链路抽象为一个服务台,下行链路抽象为另一个服务台,将休眠状态和侦听状态抽象为休假期,建立了一个两服务台同步休假的多重休假排队系统。应用半马尔可夫过程方法,导出了排队系统的稳态分布。给出了IEEE 802.16e节能类型III中上/下链路数据帧的平均延时和能量节省率等性能指标的表达式,并通过数值例子定量刻画了系统参数对系统性能的影响。

PERFORMANCE ANALYSIS OF POWER SAVING CLASS OF TYPE Ⅲ IN IEEE 802.16E WITH USER INITIATED TRAFFIC

A novel method for analysing the performance of power saving class of Type III in IEEE 802.16e is proposed, which is applicable to design, maintenance and management for mobile wireless metropolitan area network. Considering the memoryless nature of user initiated packet arrival, a Geom/G/1 queue model with multiple vacations and setup period is built to capture the principle for the power saving class of Type III. By using an embedded Markov chain method and the boundary state variable theory, we obtain the queueing measures such as queueing length, waiting time and busy cycle in steady state. Correspondingly, we derive explicitly the performance measures for the power saving class of Type III in terms of handover ratio, energy saving ratio, and average packet response time. Based on numerical results, we develop a cost function to determine numerically the optimal length of sleep window and the minimal cost with different offered loads.

主厂房岩壁梁岩台精细控制爆破试验研究

文中依托文登抽水蓄能电站主厂房工程,采用爆破方案设计、现场试验和监测的方法,提出了基于大洞室分部开挖的岩台预裂爆破和光面爆破相结合的精细控制爆破方法。提出了预裂孔和光爆孔的炮孔设计参数、装药量与装药结构优化参数和精细起爆顺序,实现了岩台壁面均匀、规则的爆破开挖。结果表明,应用提出的精细控制爆破方法,岩台倾斜壁面和边墙壁面均成形光滑,炮孔残痕率达到96%,岩台基础整体成形质量好。基于爆破振动监测结果,岩台开挖分部单独起爆爆破振动速度较小,最大振速仅为0.33 cm/s,爆破频率为120 Hz以下的中低频段,爆破频率较小,表明岩台爆破周围岩体的损伤较小。

三类油层三元复合驱提高采收率可行性研究

通过室内实验评价了三类油层三元复合驱注入能力、提高采收率幅度及化学剂吸附损失程度。结果表明:三类油层三元复合驱可比水驱提高采收率16.93%;在有效渗透率30×10^(-3)μm^2以上的油层三元复合体系能够实现正常注入,三类油层的碱敏性不会对油层产生严重的伤害;与一、二类油层相比,三类油层聚合物的吸附量相近,表面活性剂的吸附量增加约20%,三元复合驱时需要考虑表面活性剂吸附损失的影响。根据实验结果及驱油机理分析,认为三元复合驱应用于三类油层是可行的。

骨性安氏Ⅲ类患者双颌手术后软硬组织变化的相关性研究

目的用X线头颅侧位定位片,研究经上颌LeFortI型前移和下颌后退术后的骨性安氏III类患者软硬组织在水平关系上的移动比例。方法对20例骨性安氏III类患者应用手术前后X线头颅侧位定位片的相同测量点在水平轴上的差值,进行相关软硬组织比值计算和相关系数的统计学处理。结果所有下颌测量点的相关软硬组织都有相关关系,r>0.8,P<0.001。下颌除颏前点移动比值低于1外,其余为1∶1关系。上颌鼻下点与相应骨组织的相关关系较差,r<0.5,P>0.05,无统计学意义。结论上颌鼻下点与相关骨组织的相关关系较差,受诸多因素影响。下颌骨定点明确。研究骨性安氏III类患者双颌手术后的软硬组织比值变化,可为准确预测术后面容改善提供参考。