How well do integrated 3D models predict alveolar defects after treatment with clear aligners?

ObjectivesTo evaluate the accuracy of integrated models (IMs) constructed by pretreatment cone-beam computed tomography (pre-CBCT) in diagnosing alveolar defects after treatment with clear aligners.Materials and MethodsPre-CBCT and posttreatment cone-beam computed tomography (CBCT) scans from 69 patients who completed nonextraction treatment with clear aligners were collected. The IMs comprised anterior teeth in predicted positions and alveolar bone from pre-CBCT scans. The accuracy of the IMs for identifying dehiscences or fenestrations was evaluated by comparing the means of the defect volumes, absolute mean differences, and Pearson correlation coefficients with those measured from post-CBCT scans. Defect prediction accuracy was assessed by sensitivity, specificity, positive predictive values, and negative predictive values. Factors possibly affecting changes in mandibular alveolar defects were analyzed using a mixed linear model.ResultsThe IM measurements showed mean deviations of 2.82 ± 9.99 mm³ for fenestrations and 3.67 ± 9.93 mm³ for dehiscences. The absolute mean differences were 4.50 ± 9.35 mm³ for fenestrations and 5.17 ± 9.24 mm³ for dehiscences. The specificities of the IMs were higher than 0.8, whereas the sensitivities were both lower (fenestration = 0.41; dehiscence = 0.53). The positive predictive values were unacceptable (fenestration = 0.52; dehiscence = 0.62), and the overall reliability was low (<0.80). Molar distalization and proclination were positively correlated with significant increases in alveolar defects at the mandibular incisors after treatment.ConclusionsAlveolar defects after clear aligner treatment cannot be simulated accurately by IMs constructed from pre-CBCT. Caution should be taken in the treatment of crowding with proclination and molar distalization for the safety of alveolar bone at the mandibular incisors.     

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??Vitamin D3 has shown its multiple roles in both inflammation and immunity regulation in decades. Nowadays it’s been proved that local application of vitamin D3 can suppress the onset and development of periodontitis with diabetes. This review generally focuses on recent researches about how vitamin D3 functions when diabetic periodontitis takes place.      

Can the intra-examiner variability of Little's Irregularity Index be improved using 3D digital models of study casts?

Objectives

To compare contact point displacement measurements, used to determine the Little's Irregularity Index (LII) score on study casts and digital models of study casts by an independent examiner.

Methods

The contact point displacement measurements of the six maxillary anterior labial teeth were measured on ten study casts using digital callipers and their associated digital models using Creo Parametric software on five occasions following scanning using a LAVA Chairside Oral Scanner (LCOS) three-dimensional (3D) intra oral scanner. Means, standard deviations and coefficients of variation (CoV) were determined, data analyses (Pearson's correlation coefficients (PCCs) and Intraclass correlation coefficients (ICCs)) and statistical analyses (three and two-way analyses of variance (ANOVAs) and Independent Sample Student's t-tests) were carried out (p < 0.05).

Results

Significant positive correlations for the contact point displacement measurements were evident between all measurement time points for the study casts (r > 0.978; p < 0.0001 and ICC > 0.910; p < 0.0001) and the digital models (r > 0.963; p < 0.0001 and ICC > 0.986; p < 0.0001). The CoV results showed that the contact point displacement measurement data from the digital models was more reproducible than the study casts. Of the 50 Independent Sample Student's t-tests, 21 significant increases (p < 0.042) were reported in contact point displacement measurements <2.9 mm for the digital models compared with the study casts.

Conclusion

The use of 3D digital models can improve the reliability of LII measurements by reducing the subjectivity associated with choosing the anatomic tooth contact points and the awkwardness of measuring the contact point displacements on study casts using a cumbersome calliper technique.

Clinical significance

Intra-examiner variability in the measurement of LII is still evident with digital models suggesting that either improved software specifically aimed at the orthodontic community be identified or a new method for measuring anterior incisor crowding be sought.     

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随着科技的发展,人类社会迈入了数字化时代。数字化技术与医学的完美结合形成了数字医学这一崭新学科。3D打印技术正是在这一背景下出现的一种全新的制造技术。3D打印技术改变了传统制造模式,是数字医学发展进程中的一个重要环节。     

Dental imaging—2D to 3D: a historic,current, and future view of projection radiography

Projection radiography, developed over 100 years ago, has helped transform Dentistry into a sophisticated evidence-based healthcare profession. It has been an international collaboration of research that created the technology we now use. The following essay reviews the history behind the technology and provides examples of its current endodontic applications. The dangers of ionizing radiation have pushed the science of imaging into new frontiers. New imaging processes that use magnetic resonance, ultrasound, and infrared technology may supersede the need to use x-rays. Change is a constant in imaging. Future applications will go beyond the imagination of the inventors.     

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??Objective??The 3shape Trios intraoral intraoral scanner combined with 3D printing technology is used to make single crown restoration??determine its feasibility??and discuss and evaluate the clinical effectiveness and patient satisfaction. Methods??In this study??32 patients whose single premolar teeth needed crown restoration were included and divided into two groups randomly??the experimental group??16 patients??and control group??16 patients??. In the experimental group??the restorations were made by 3 shape Trios and 3D printer. As for the control group??the regular design method was applied to restore their teeth. The time consumed in the first insertion of each restoration in both groups was recorded. The quality of the prostheses was assessed by another dentist. The prostheses satisfactions were evaluated by the patients. Results??The acceptance rate of the patients on the digital rehabilitation in the experimental group was 100%. There was no significant difference in the quality of the prostheses between the two groups. The satisfaction rate of the patients on prostheses and facial appearance was significantly higher in the experimental group than in control group??P < 0.05??. In addition?? the time consumed in the first insertion of the experimental group was much shorter than that in the control group??P < 0.05??. Conclusion??The new method of the 3shape Trios scanner combined with 3D printer for making single crown is a practical technique. This method is useful in shortening the time consumed in the restoration of single crown??improves the patient satisfaction of the prostheses.     

Comparison of 3D plate and locking plate in treatment of mandibular fracture—a clinical study

Introduction

This study was performed to evaluate the efficacy and post-operative complication of 3-dimensional (3D) titanium miniplate and locking plate in mandibular fractures (parasymphysis, symphysis, body, and angle).

Materials and methods

Forty patients, with non-comminuted mandibular fractures treated with open reduction and internal fixation using 3D titanium miniplate system or locking plate system through an intra-oral approach, were included in this study. All patients were systematically monitored up to 2 months post-operatively. Parameters recorded were infection, occlusal discrepancies, hardware failure, wound dehiscence, sensory disturbance of the inferior alveolar nerve, and stability of fractured segments.

Results

Forty patients with mandibular fracture were divided into two groups randomly without any bias. The fractures of all 40 patients were found to be adequately fixed when checked intra-operatively after fixation. One patient (2.5%) of the 3D plate group developed an infection on the first and second post-operative visit and was treated by antibiotic coverage. One patient in the locking plate group (2.5%) reported wound dehiscence after the first week follow-up.

Conclusion

Both 3D titanium miniplates and locking plate are effective in the treatment of mandibular fractures, and overall complication rates are lesser. However, the 3D plating system uses less hardware in cases of parasymphysis and symphysis fractures and more hardware in cases of body and angle fractures.

     

3D打印及其在口腔医学中的应用(一)——3D打印技术的工作原理

3D打印技术已经在口腔医学中得到了广泛的应用,是口腔数字化技术的核心环节之一,目前很多临床技术都是基于3D打印实现的。了解其基本原理、常用的打印工艺、口腔领域应用的打印材料等基础知识,能够帮助我们在临床工作中更好的应用这项技术。该文对3D打印的基本原理、模型文件及其格式、打印前模型的处理等内容结合实际应用进行了介绍。     

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??Objective    To explore a new type of lingual orthodontics design and direct manufacturing technology with 3D printing and to supply experiment evidence for clinical application. Methods    From January 2014 to January 2015??40 patients who received orthodontic treatment in our hospital were randomly divided into experiment group and control group??each with 20 cases??the control group received routine oral tongue side orthodontic brackets??the experiment group used a 3D printer to print the oral tongue side orthodontic bracket. For patients in the experiment group tooth-model data were obtained through CT scanning??and the data were put into Mimics software for post-processing??and then through reverse technology??mirror imaging????date were converted to the tooth computer aided design??CAD??model. The project was determined by modeling tooth movement and customized lingual bracket was manufactured by selective laser melting rapid prototyping oral special 3D printing device. Results    Clinical effective rate were 95% and 75% in experiment group and control group respectively after 6 months follow-up??the experiment group's was significantly higher than that of the control group??P < 0.05??. The complication rate was 5% in the experiment group and was significantly lower than that of the control group ??25%??. Conclusion    The clinical application effect of the using 3D printing technology in manufacturing customized lingual bracket is satisfactory. When using 3D printing mathch degree is high and the bonding location is accurate. It's easy to operate??and from clinical long-term perspective??it is not easy to fall off and greatly simplifies the procedures.     

口腔3D打印材料的研究现状

3D打印在口腔中的的应用已经非常普遍,可以立体、直观、清晰、全面的显示颌面部复杂的解剖结构,对牙齿以及颌骨周围组织的关系还有患者个性化的解剖结构都能以实物的复制体精确地展示出来,对指导临床治疗以及医生在制定手术计划时起了非常大的作用。该技术在颌骨手术,种植,烤瓷冠桥修复领域应用已比较广泛。然而,目前3D打印在口腔有些领域的应用还存在一些问题,比如活动义齿金属支架和全瓷冠桥等,其中打印材料也是重要的影响因素,为了明晰其研究发展动态,本文将对口腔3D打印材料的研究进展做一综述。     

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??Digital medical as a product of digital technology combined with medicine??has gotten rapid development in recent years. Digital 3D printing is a newly emerged technology in this background. Digital 3D printing technology has changed the traditional medicine pattern??especially in the field of surgical medical. It mainly reflects in evaluation and forecast risk before the operation??real-time navigation in the process of the operation and evaluation of surgical effects after the operation.This paper introduces the application of digital 3D printing technology in the treatment of OSAHS.     

骨组织工程3D生物打印的研究进展

近几十年来,骨组织工程在骨缺损修复治疗的应用中获得了飞速的发展,而3D生物打印是近十年来在骨组织工程中一种非常具有前景的技术.传统骨组织工程支架制造方法无法精确控制空间结构,且在支架制作完成后接种细胞也无法控制细胞的均匀分布.尽管3D生物打印作为一类含细胞骨组织工程支架制造技术,以水凝胶类材料作为基础将细胞置入支架中,...     

3D打印无牙颌个别托盘的初步研究

目的探讨3D打印无牙颌个别托盘较传统方法制作的个别托盘1是否能有效减少临床椅旁操作时间;2托盘印模面处理后与藻酸盐印模材间的固位强度比较和变化。方法 1选取全口义齿修复患者10例,上颌为A组,下颌为B组,记录3D打印法和传统方法(自凝丙烯酸树脂)制作个别托盘的椅旁工作时间;2测量3D打印托盘和传统托盘(光固化树脂和自凝丙烯酸树脂)的印模面3种情况下(以不处理、打孔和涂布托盘粘接剂)与藻酸盐印模材间的固位强度。结果 1A、B组3D打印法分别是34.37、28.19 min,传统法分别是64.95、63.94 min,3D打印无牙颌个别托盘的时间均显著少于传统法的时间(P<0.05);23D打印托盘表面涂粘接剂组固位强度为2.31 N/cm~2,为组内最佳(析因方差分析P<0.01)。结论 3D打印无牙颌个别托盘相对于传统方法可有效减少椅旁工作时间;与藻酸盐印模材间具有良好的固位强度,打孔及表面涂托盘粘接剂均可明显提高其固位强度,表面涂粘接剂效果更明显。     

运用CEREC3D设计制作贴面体会

全瓷贴面具有磨牙少和色彩效果好等优点,特别适合于前牙及前磨牙的釉质发育不全、酸蚀牙、氟斑牙和四环素牙等的唇面修复。CAD/CAM方式是制作全瓷贴面的较新方法[1],据Wiedhahn(2006)报道以这种方式制作的全瓷贴面九年成功率达到94%[2]。本文总结了31例彩CEREC3D系统制作全瓷贴面的操作经验。1资料与方法1·1一般资料患者31例(72颗牙),男12例,女19例;年龄21~42岁;其中上颌牙29例,下颌牙2例。均为牙体组织轻微缺损、变色牙或氟斑牙等。1·2方法采用CEREC3D系统(西诺德,德国),VITA MKII(维他,德国)成品切削瓷块,VITA VM9(维他,…     

维生素D3与伴糖尿病的牙周炎

随着对维生素D3研究的逐渐深入,其在免疫、炎症等方面的积极作用为伴糖尿病的牙周炎的治疗指明了新的探索方向。维生素D3通过多种途径影响伴糖尿病的牙周炎患者的局部及全身健康状态。现对近年来有关维生素D3调节伴糖尿病的牙周炎作用机制方面的研究做一介绍。     

3D打印在口腔美学修复中的应用

3D打印技术可完成结构复杂物体的打印,在口腔修复领域已有一定应用,未来有望替代大部分传统修复技术。在口腔美学修复中如何保证分析设计阶段初设的轮廓外形与颜色等与患者得到的最终修复体一致,一直是困扰口腔医师和技师的难题。3D打印的蜡型、树脂冠桥等可用于美学修复的美学分析和设计结果的输出预告,一对一地传递并指导最终修复体的设计和制作。3D打印的目标修复体导板（TRSguide）既为美学修复制定了可预览的修复蓝图,让口腔医师和技师能检测患者重建的口腔功能和美学的相关信息;又能指导实施符合牙体保存和活髓保护理念的理想牙预备,做到真正的全程精准与微创。这些新的数字化技术进展使得美学修复焕然一新。本文对3D打印在口腔美学修复中的应用进行介绍。     

3D FIESTA脉冲序列评价胎儿面部的研究

目的:应用3D FIESTA脉冲序列评价正常和异常的胎儿面部,并与二维MRI和三维超声比较分析图像质量和诊断性能。方法:将65名怀疑或诊断为先天性胎儿面部畸形的孕妇纳入研究,进行二维MRI(SSFSE和FIESTA序列)和三维MRI(FIESTA序列)检查。比较分析三维MRI和三维超声的图像质量,同时分别计算3D FIESTA、三维超声和二维MRI的敏感性、特异性、阴性预测值(NPV)、阳性预测值(PPV)和准确性。以随访结果作为参考标准,用曲线下面积(AUC)来比较分析诊断效能。结果:总共评价了549个面部结构。三维MRI和三维超声的观察者间相关性非常好(逐段分析κ值0.63～0.89)。3D FIESTA敏感性、特异性、NPV、PPV和准确性分别为89.7%、99.2%、99.2%、90.0%和98.5%,而三维超声分别为87.1%、98.8%、99.0%、85.0%和98.0%,二维MRI分别为74.3%、98.2%、98.0%、76.3%和96.5%。3D FIESTA、三维超声和二维MRI的AUC分别为0.94、0.93和0.86。结论:运用3D FIESTA评估正常和异常胎...