American Journal of Orthodontics and Dentofacial Orthopedics最新文献

英文中文

Nanomechanical and bending properties of nickel-titanium orthodontics archwires by depth-sensing indentation 通过深度感应压痕分析镍钛正畸弓丝的纳米力学性能和弯曲性能。

IF 2.7 2区医学 Q1 DENTISTRY, ORAL SURGERY & MEDICINE

American Journal of Orthodontics and Dentofacial Orthopedics

Pub Date : 2025-01-01 DOI: 10.1016/j.ajodo.2024.08.009

Alfredo Nevárez-Rascón , Abel Hurtado-Macías , Martina M. Nevárez-Rascón , María José Rodríguez-Rondón , Jesus Eduardo Leal-Perez , Raul Herrera-Basurto , Gregorio Vázquez-Olvera , Orlando Auciello

Introduction

This study aimed to identify the link between alloy microstructures and the nanomechanical properties of different orthodontic archwires containing nickel-titanium (NiTi) by sensing sliced areas. Previous studies have focused on analyzing and contrasting physical properties such as microhardness, elasticity modulus, and resistance; therefore, the trend is to consider microstructural characteristics in detail.

Methods

Thirty archwire samples from 3 different commercial brands, American Orthodontics (AO), 3M Unitek (3M), and Borgatta, were analyzed through scanning electron microscopy and energy-dispersive x-ray spectroscopy, transmission electron microscopy, atomic force microscopy, Berkovich nanoindentation, and microtensile microscopy to determine their chemical-crystallographic characteristics and nanomechanical and bending characteristics.

Results

The identified formulations of AO and 3M had averages of 20 wt%, for Ni and 15.4 wt% for Ti, with lower concentrations for Borgatta. Alloys of Ni and Ti were distributed in different concentrates in the matrix of the archwires. The nanomechanical properties showed high values of the elastic modulus (82.8 ± 3.6 GPa) and hardness (6.4 ± 1.2 GPa) and a minor deformation degree of 0.38% for the AO wires, although the bending strength exhibited the highest values for 3M. No corrosion was observed with a prolonged hydrolytic attack on the surface of any of the wires (0.0-0.5 National Bureau of Standards units).

Conclusions

The highest nanomechanical properties and bending characteristics were observed for wires with higher NiTi precipitate contents, which were distributed differently in the alloy overall in the matrix. The nanoindentations sensed in different areas evidenced different mechanical properties for NiTi depending on its concentrations of Ti and enucleations.

简介：本研究旨在通过感应切片区域，确定合金微结构与含镍钛（NiTi）的不同正畸弓丝的纳米力学性能之间的联系。以往的研究侧重于分析和对比微硬度、弹性模量和电阻等物理特性，因此，详细考虑微结构特性是大势所趋：通过扫描电子显微镜和能量色散 X 射线光谱、透射电子显微镜、原子力显微镜、Berkovich 纳米压痕和显微拉伸显微镜分析了来自 3 个不同商业品牌（美国正畸公司（AO）、3M Unitek（3M）和 Borgatta）的 30 个弓丝样品，以确定它们的化学晶体学特性以及纳米力学和弯曲特性：已确定的 AO 和 3M 配方中，镍的平均含量为 20 wt%，钛的平均含量为 15.4 wt%，而 Borgatta 的含量较低。镍和钛合金以不同的浓度分布在弓丝基体中。纳米力学性能显示，AO 金丝的弹性模量（82.8 ± 3.6 GPa）和硬度（6.4 ± 1.2 GPa）值较高，微变形度为 0.38%，但 3M 金丝的弯曲强度值最高。任何金属丝表面在长时间的水解作用下（0.0-0.5 国家标准局单位）均未出现腐蚀现象：结论：镍钛析出物含量较高的金属丝具有最高的纳米力学性能和弯曲特性，镍钛析出物在合金基体中的总体分布情况不同。不同区域的纳米压痕表明，镍钛的机械性能因其钛含量和析出物而异。

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引用次数: 0

Training, use, and modifications related to artificial intelligence in postgraduate orthodontic programs in North America 北美正畸研究生课程中与人工智能相关的培训、使用和修改。

IF 2.7 2区医学 Q1 DENTISTRY, ORAL SURGERY & MEDICINE

American Journal of Orthodontics and Dentofacial Orthopedics

Pub Date : 2025-01-01 DOI: 10.1016/j.ajodo.2024.09.008

Joshua Hanenkrath , Jae Hyun Park , Curt Bay

Introduction

The use of artificial intelligence (AI) is growing quickly and has already had a significant impact on the practice of orthodontics. This study aimed to explore the degree to which the study and use of AI have been integrated into accredited postgraduate orthodontic programs in North America.

Methods

An anonymous electronic survey was sent to each of North America’s 74 orthodontic residency programs, requesting information from either the program director or department chair. Data were collected and analyzed using SPSS (version 28; IBM, Armonk, NY) and Excel (Microsoft, Redmond, Wash).

Results

Forty-one valid surveys were analyzed. Among the respondents, 56.1% had implemented or planned to implement AI instruction into their program. Among those who reported using this technology, 60.9% indicated that they have applied these principles for research purposes. Most respondents (87.8%) noted that they have not developed seminars and/or AI training to be included in their curriculum, whereas residents in 17.1% of respondent programs have advocated for these modifications. Lack of expertise and availability in the schedule (71.4%) are common challenges associated with the dearth of curriculum changes. Most programs (68.3%) encouraged their residents to attend continuing education for AI fundamentals, while 75.6% reported that they do not encourage their residents to use AI for patient care, research, or didactic assignments. Several programs (68.3%) reported not updating their academic manuals and syllabi with new AI policies, nor have they installed new AI detection software (80.5%).

Conclusions

More than half of orthodontic residencies have implemented AI into their program in some capacity. The continual advancements of AI algorithms will require modifications to orthodontic residency programs. AI-related education should be implemented into academic curricula to provide residents with the tools necessary to thrive in an AI-driven practice.

导言：人工智能（AI）的应用发展迅速，已经对正畸学的实践产生了重大影响。本研究旨在探讨人工智能的研究和使用在多大程度上已被纳入北美经认证的正畸研究生课程：向北美 74 个正畸住院医师培训项目中的每个项目发送了匿名电子调查表，要求项目主任或系主任提供相关信息。使用 SPSS（28 版；IBM，Armonk，NY）和 Excel（Microsoft，Redmond，Wash）收集和分析数据：对 41 份有效调查问卷进行了分析。在受访者中，56.1%的人已经或计划在他们的课程中实施人工智能教学。在报告使用该技术的受访者中，60.9%的人表示已将这些原则用于研究目的。大多数受访者（87.8%）指出，他们没有在课程中纳入研讨会和/或人工智能培训，而 17.1% 的受访项目中的住院医师主张进行这些修改。课程表中缺乏专业知识和可用性（71.4%）是与缺乏课程改革相关的共同挑战。大多数项目（68.3%）鼓励住院医师参加人工智能基础知识的继续教育，而75.6%的项目报告称，他们不鼓励住院医师将人工智能用于患者护理、研究或教学任务。一些项目（68.3%）报告说，他们没有根据新的人工智能政策更新学术手册和教学大纲，也没有安装新的人工智能检测软件（80.5%）：结论：超过一半的正畸住院医师已经在他们的项目中以某种方式实施了人工智能。人工智能算法的不断进步需要对正畸住院医师培训项目进行修改。人工智能相关教育应纳入学术课程，为住院医师提供在人工智能驱动的实践中茁壮成长所需的工具。

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引用次数: 0

Trial sequential analysis: Reducing the likelihood of false-positive findings of meta-analyses 试验序贯分析：减少meta分析假阳性结果的可能性。

IF 2.7 2区医学 Q1 DENTISTRY, ORAL SURGERY & MEDICINE

American Journal of Orthodontics and Dentofacial Orthopedics

Pub Date : 2025-01-01 DOI: 10.1016/j.ajodo.2024.10.002

Yu-Kang Tu , Fang Hua , Nikolaos Pandis

引用次数: 0

January 2025 Continuing Education

IF 2.7 2区医学 Q1 DENTISTRY, ORAL SURGERY & MEDICINE

American Journal of Orthodontics and Dentofacial Orthopedics

Pub Date : 2025-01-01 DOI: 10.1016/j.ajodo.2024.11.003

Dr Allen H. Moffitt (CE Editor)

引用次数: 0

How environmentally friendly is the disposal of clear aligners? A gas chromatography-mass spectrometry study 透明对齐器的处理有多环保？气相色谱-质谱法研究。

IF 2.7 2区医学 Q1 DENTISTRY, ORAL SURGERY & MEDICINE

American Journal of Orthodontics and Dentofacial Orthopedics

Pub Date : 2025-01-01 DOI: 10.1016/j.ajodo.2024.08.011

Elbe Peter , J. Monisha , V.P. Sylas , Suja Ani George

Introduction

Used clear aligner trays are often indiscriminately disposed of with general plastic waste and incinerated. This study aimed to analyze the smoke composition from incinerating 2 common aligner materials: glycol-modified polyethylene terephthalate (PET-G) and polyurethane.

Methods

Each of the 2 materials in triplets was thermoformed. The thermoformed trays were shredded and subjected individually to open-fire combustion, ignited using a methane torch, in a specially designed combustion chamber. The resultant smoke was collected and analyzed using gas chromatography-mass spectrometry to study its in-depth composition.

Results

A total of 20 peaks, corresponding to 20 compounds, were identified from each of the 2 material samples. O-xylene (21.06%) showed the maximum concentration in the PET-G sample, whereas 1,4-dimethyl-1,3-cyclohexadiene in polyurethane (18.88%). The first peak in the PET-G sample corresponded to benzene with a relative concentration of 5.18%. Four compounds were common to both samples: 1,4-dimethyl-1,3-cyclohexadiene; 1,3-cyclohexadiene, 2,3-dimethyl-; 1-hydroxymethly-4-methylenecyclohexane; and cyclohexanemethanol, 4-methylene-.

Conclusions

Benzene, a group 1 carcinogen, was identified in the PET-G smoke sample, whereas tetrahydrofuran, a suspected carcinogen, was found in the polyurethane sample. Some compounds were hazardous, whereas most were skin, eye, and respiratory irritants. Possible mitigation strategies include proper case selection, efficient manufacturing, direct 3-dimensional printing, and developing biodegradable materials. Clinicians can set up ‘used aligner collection points’ to ensure responsible disposal. Proper disposal guidelines and stringent regulations are the need of the hour.

介绍：用过的透明对齐器托盘经常被随意丢弃，与一般塑料垃圾一起焚烧。本研究旨在分析焚烧乙二醇改性聚对苯二甲酸乙二酯（PET-G）和聚氨酯这两种常见对齐器材料所产生的烟雾成分：方法：将 2 种材料的三联体分别进行热成型。热成型托盘被切碎，并在专门设计的燃烧室中分别进行明火燃烧，使用甲烷火炬点燃。收集所产生的烟雾，并使用气相色谱-质谱法分析其深度成分：结果：从两种材料样品中分别鉴定出 20 个峰值，对应 20 种化合物。在 PET-G 样品中，邻二甲苯（21.06%）的浓度最高，而在聚氨酯中，1,4-二甲基-1,3-环己二烯（18.88%）的浓度最高。PET-G 样品中的第一个峰值是苯，相对浓度为 5.18%。两种样品共有四种化合物：1,4-二甲基-1,3-环己二烯；1,3-环己二烯，2,3-二甲基；1-羟甲基-4-亚甲基环己烷；以及环己基甲醇，4-亚甲基：在 PET-G 烟雾样本中发现了 1 类致癌物苯，而在聚氨酯样本中发现了疑似致癌物四氢呋喃。有些化合物是有害的，而大多数是皮肤、眼睛和呼吸道刺激物。可能的缓解策略包括正确选择病例、高效制造、直接三维打印以及开发可生物降解的材料。临床医生可以设立 "废旧矫治器收集点"，确保以负责任的方式进行处理。适当的处置指南和严格的法规是当务之急。

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引用次数: 0

The periodontal ligament-periosteum sandwich hypothesis: A thought experiment on fenestrations and dehiscences 牙周韧带-骨膜三明治假说：关于裂隙和开裂的思想实验。

IF 2.7 2区医学 Q1 DENTISTRY, ORAL SURGERY & MEDICINE

American Journal of Orthodontics and Dentofacial Orthopedics

Pub Date : 2025-01-01 DOI: 10.1016/j.ajodo.2024.08.017

Greg J. Huang

This article describes a hypothesis for bone recovery after iatrogenic dehiscences or fenestrations. When roots are moved out of the alveolar bone, the periodontal ligament and periosteum form a bilayer membrane (sandwich) over the exposed root. If the root is allowed to relapse back toward its original position, bone recovery will occur between the periodontal ligament and periosteum.

本文介绍了一种关于先天性开裂或瘘管后牙槽骨恢复的假说。当牙根移出牙槽骨时，牙周韧带和骨膜会在暴露的牙根上形成一层双层膜（三明治）。如果允许牙根向原来的位置复位，牙周韧带和骨膜之间的骨质就会恢复。

引用次数: 0

Effects of curing lights on polymerization shrinkage of composite attachments in clear aligner treatment: A microcomputed tomography study 固化灯对透明矫治器治疗中复合附着体聚合收缩的影响：微计算机断层扫描研究。

IF 2.7 2区医学 Q1 DENTISTRY, ORAL SURGERY & MEDICINE

American Journal of Orthodontics and Dentofacial Orthopedics

Pub Date : 2025-01-01 DOI: 10.1016/j.ajodo.2024.08.012

Irmak Ocak , Muge Aksu

Introduction

This study aimed to investigate the polymerization shrinkage of composite attachments and changes in attachment templates during bonding in clear aligner treatments.

Methods

A total of 24 extracted teeth were divided into 4 groups, and plaster models were digitized. Attachment templates were produced with beveled attachments on premolars and rectangular attachments on molars. Polymerizations used a halogen curing light (800 milliwatts per square centimeter [mW/cm²] for 20 seconds) and light-emitting diode (LED) curing light in 3 modes (1000 mW/cm² for 20 seconds, 1000 mW/cm² for 10 seconds, and 3200 mW/cm² for 3 seconds). The curing distance was 5 mm, and temperature changes were recorded with a thermal camera. Microcomputed tomography scanning measured volumetric and linear attachments before and after polymerization. Statistical analyses employed a 1-way analysis of variance with Bonferroni corrected Tukey post-hoc for multiple comparisons and the Kruskal-Wallis test for temperature change.

Results

Significant differences (P <0.001) were found in temperature among curing lights. The highest temperature was in the LED unit-extra mode, and the lowest was in the halogen curing unit. The LED unit for 20 seconds caused the highest temperature change. A significant difference (P = 0.048) in occlusal attachment length was found between the LED unit for 20 seconds and the LED unit-extra mode. Polymerization resulted in increased attachment template thickness across all groups, with significant changes noted in the halogen unit, LED unit for 20 seconds, and LED unit-extra mode.

Conclusions

Temperature generated during polymerization varied between halogen and LED curing lights. Significant differences were found in attachment length at the occlusal level and template thickness postpolymerization. Preferences in attachment bonding protocols may affect the clinical precision of clear aligner treatments.

简介：本研究旨在探讨透明矫治器治疗过程中复合附着体的聚合收缩和附着模板的变化：本研究旨在探讨透明矫治器治疗过程中复合附着体的聚合收缩和附着体模板的变化：方法：将 24 颗拔牙分为 4 组，并对石膏模型进行数字化处理。制作的附着体模板前磨牙为斜面附着体，磨牙为矩形附着体。聚合时使用卤素固化灯（800 毫瓦/平方厘米 [mW/cm2] 20 秒）和发光二极管固化灯（1000 毫瓦/平方厘米 20 秒、1000 毫瓦/平方厘米 10 秒和 3200 毫瓦/平方厘米 3 秒）三种模式。固化距离为 5 毫米，用热像仪记录温度变化。显微计算机断层扫描测量了聚合前后的体积和线性附着情况。统计分析采用单因素方差分析，多重比较采用 Bonferroni 校正的 Tukey post-hoc 检验，温度变化采用 Kruskal-Wallis 检验：差异显著（P卤素灯和 LED 固化灯在聚合过程中产生的温度不同。在咬合水平的附着长度和聚合后的模板厚度方面存在显著差异。对附着粘接方案的偏好可能会影响透明矫治器治疗的临床精确度。

{"title":"Effects of curing lights on polymerization shrinkage of composite attachments in clear aligner treatment: A microcomputed tomography study","authors":"Irmak Ocak , Muge Aksu","doi":"10.1016/j.ajodo.2024.08.012","DOIUrl":"10.1016/j.ajodo.2024.08.012","url":null,"abstract":"<div><h3>Introduction</h3><div>This study aimed to investigate the polymerization shrinkage of composite attachments and changes in attachment templates during bonding in clear aligner treatments.</div></div><div><h3>Methods</h3><div>A total of 24 extracted teeth were divided into 4 groups, and plaster models were digitized. Attachment templates were produced with beveled attachments on premolars and rectangular attachments on molars. Polymerizations used a halogen curing light (800 milliwatts per square centimeter [mW/cm<sup>2</sup>] for 20 seconds) and light-emitting diode (LED) curing light in 3 modes (1000 mW/cm<sup>2</sup> for 20 seconds, 1000 mW/cm<sup>2</sup> for 10 seconds, and 3200 mW/cm<sup>2</sup> for 3 seconds). The curing distance was 5 mm, and temperature changes were recorded with a thermal camera. Microcomputed tomography scanning measured volumetric and linear attachments before and after polymerization. Statistical analyses employed a 1-way analysis of variance with Bonferroni corrected Tukey post-hoc for multiple comparisons and the Kruskal-Wallis test for temperature change.</div></div><div><h3>Results</h3><div>Significant differences (<em>P</em> <0.001) were found in temperature among curing lights. The highest temperature was in the LED unit-extra mode, and the lowest was in the halogen curing unit. The LED unit for 20 seconds caused the highest temperature change. A significant difference (<em>P</em> = 0.048) in occlusal attachment length was found between the LED unit for 20 seconds and the LED unit-extra mode. Polymerization resulted in increased attachment template thickness across all groups, with significant changes noted in the halogen unit, LED unit for 20 seconds, and LED unit-extra mode.</div></div><div><h3>Conclusions</h3><div>Temperature generated during polymerization varied between halogen and LED curing lights. Significant differences were found in attachment length at the occlusal level and template thickness postpolymerization. Preferences in attachment bonding protocols may affect the clinical precision of clear aligner treatments.</div></div>","PeriodicalId":50806,"journal":{"name":"American Journal of Orthodontics and Dentofacial Orthopedics","volume":"167 1","pages":"Pages 63-72"},"PeriodicalIF":2.7,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142331834","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Comparison of microbial adhesion and biofilm formation on different orthodontic aligners 不同正畸矫治器上微生物粘附和生物膜形成的比较。

IF 2.7 2区医学 Q1 DENTISTRY, ORAL SURGERY & MEDICINE

American Journal of Orthodontics and Dentofacial Orthopedics

Pub Date : 2025-01-01 DOI: 10.1016/j.ajodo.2024.08.010

Aylin Pasaoglu Bozkurt , Mehmet Demirci , Pelin Erdogan , Emre Kayalar

Introduction

This study aimed to compare and evaluate time-dependent biofilm formation and microbial adhesion on 6 different clear aligner systems: Invisalign (Align Technology, San Jose, Calif), Clarity (3M ESPE Maplewood, Minn), ClearCorrect (Institut Straumann AG, Basel, Switzerland), Smartee (Smartee Denti-Technology, Shanghai, China), Orthero (Orthero, Istanbul, Turkey) and Graphy (Graphy Inc, Seoul, South Korea).

Methods

Streptococcus mutans (ATCC 25175) and Lactobacillus acidophilus (ATCC 4356) were used to evaluate the microbial adhesion and biofilm formation on orthodontic clear aligners at the 0, 24, 48, 72, 96, 120, 168, and 240 hours. Two-way repeated measures analysis of variance (Greenhouse-Geisser) test and post-hoc Bonferroni T2 tests were used for statistical evaluation. The statistical significance level was set at P <0.05.

Results

It was found that more bacterial formation occurred on ClearCorrect than on Smartee at 120, 168, and 240 hours (P <0.05). It was observed more biofilm formation at 168 hours on Graphy than on Smartee (P <0.05). It was found that S mutans + L acidophilus formed more biofilm at 120 and 168 hours on Graphy than on Invisalign (P <0.05).

Conclusions

Elevated biofilm formation across all materials carries substantial clinical implications. Orthodontists and patients should remain aware of the increased risk of microbial colonization with extended aligner usage.

简介：本研究旨在比较和评估 6 种不同的透明矫治器系统上随时间变化的生物膜形成和微生物附着情况：Invisalign (Align Technology, San Jose, Calif)、Clarity (3M ESPE Maplewood, Minn)、ClearCorrect (Institut Straumann AG, Basel, Switzerland)、Smartee (Smartee Denti-Technology, Shanghai, China)、Orthero (Orthero, Istanbul, Turkey)和Graphy (Graphy Inc, Seoul, South Korea)：方法：使用变异链球菌（ATCC 25175）和嗜酸乳杆菌（ATCC 4356）来评估0、24、48、72、96、120、168和240小时正畸透明矫治器上的微生物粘附和生物膜形成情况。统计评估采用了双向重复测量方差分析（Greenhouse-Geisser）检验和事后 Bonferroni T2 检验。统计显著性水平设定为 P 结果：结果发现，在 120、168 和 240 小时内，在 ClearCorrect 上形成的细菌比在 Smartee 上形成的细菌多（P 结论）：所有材料的生物膜形成率都很高，这对临床有很大的影响。正畸医生和患者应始终意识到长时间使用矫治器会增加微生物定植的风险。

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引用次数: 0

Comparison of physical, mechanical, and optical properties between thermoplastic materials and 3-dimensional printing resins for orthodontic clear retainers 正畸透明固位体用热塑性材料与三维打印树脂的物理、机械和光学性能比较。

IF 2.7 2区医学 Q1 DENTISTRY, ORAL SURGERY & MEDICINE

American Journal of Orthodontics and Dentofacial Orthopedics

Pub Date : 2025-01-01 DOI: 10.1016/j.ajodo.2024.06.010

Siew Peng Neoh , Anak Khantachawana , Rochaya Chintavalakorn , Peerapong Santiwong , Toemsak Srikhirin

Introduction

This study investigated the physical, mechanical, and optical properties of 3-dimensional (3D) printing resins compared with thermoplastic materials to evaluate their suitability for the fabrication of orthodontic clear retainers.

Methods

Samples were prepared from thermoplastic sheets (Duran [Scheu-Dental GmbH, Iserlohn, Germany] and Zendura [Bay Materials LLC, Fremont, Calif]) and biocompatible 3D-printing resins (Dental LT Clear V2 [Formlabs Inc, Somerville, Mass] and OrthoFlex [Nextdent BV, Soesterberg, The Netherlands]) according to the manufacturer’s instructions. The materials were characterized by Fourier transform infrared spectroscopy, differential scanning calorimetry, and water sorption tests. Mechanical properties were assessed by tensile tests and hardness under 3 different conditions: dry, wet (24-hour water immersion), and aged (thermocyled for 10,000 cycles). Surface characteristics were qualitatively and quantitatively evaluated by scanning electron microscopy and 3D confocal imaging, respectively. Optical properties were assessed by ultraviolet-visible spectroscopy and color stability tests by immersion into various staining solutions.

Results

The mechanical properties of the 3D-printing resins were more markedly altered in different testing conditions (dry, wet, and aged) than in thermoplastic materials. The surface roughness, transparency, and color stability of 3D-printing resins are significantly inferior, especially NextDent OrthoFlex.

Conclusions

The evaluated 3D-printing resins are more brittle and less ductile compared with the thermoplastic materials. The 3D-printing resins also do not meet the clinical thresholds of surface roughness and optical properties for the fabrication of orthodontic clear retainers. Further postprocessing of the 3D-printing resins may be required to improve these properties.

前言：本研究对比了3D打印树脂与热塑性塑料的物理、机械和光学性能，以评估其在正畸透明固位器制造中的适用性。方法：根据制造商的说明，用热塑性片材（Duran [scheui -Dental GmbH, Iserlohn， Germany]和Zendura [Bay Materials LLC， Fremont, Calif .]）和生物相容性3d打印树脂（Dental LT Clear V2 [Formlabs Inc, Somerville， Mass]和OrthoFlex [Nextdent BV， Soesterberg, The Netherlands]）制备样品。采用傅里叶变换红外光谱、差示扫描量热法和吸水性测试对材料进行了表征。通过3种不同条件下的拉伸试验和硬度来评估机械性能：干燥、潮湿（24小时水浸泡）和老化（10,000次热循环）。通过扫描电镜和三维共聚焦成像分别对其表面特征进行定性和定量评价。通过紫外可见光谱和浸渍于不同染色溶液的颜色稳定性测试来评估其光学性能。结果：3d打印树脂的机械性能在不同的测试条件下（干燥、潮湿和老化）比热塑性材料有更明显的变化。3d打印树脂的表面粗糙度、透明度和颜色稳定性明显较差，特别是NextDent OrthoFlex。结论：与热塑性材料相比，所评价的3d打印树脂更脆，韧性更差。3d打印树脂的表面粗糙度和光学性能也不符合制造正畸透明固位器的临床阈值。为了提高这些性能，可能需要对3d打印树脂进行进一步的后处理。

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引用次数: 0

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IF 2.7 2区医学 Q1 DENTISTRY, ORAL SURGERY & MEDICINE

American Journal of Orthodontics and Dentofacial Orthopedics

Pub Date : 2025-01-01 DOI: 10.1016/S0889-5406(24)00491-8

引用次数: 0

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