American Journal of Orthodontics and Dentofacial Orthopedics最新文献

{"title":"Nanomechanical and bending properties of nickel-titanium orthodontics archwires by depth-sensing indentation","authors":"Alfredo Nevárez-Rascón ,&nbsp;Abel Hurtado-Macías ,&nbsp;Martina M. Nevárez-Rascón ,&nbsp;María José Rodríguez-Rondón ,&nbsp;Jesus Eduardo Leal-Perez ,&nbsp;Raul Herrera-Basurto ,&nbsp;Gregorio Vázquez-Olvera ,&nbsp;Orlando Auciello","doi":"10.1016/j.ajodo.2024.08.009","DOIUrl":"10.1016/j.ajodo.2024.08.009","url":null,"abstract":"<div><h3>Introduction</h3><div>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.</div></div><div><h3>Methods</h3><div>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.</div></div><div><h3>Results</h3><div>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).</div></div><div><h3>Conclusions</h3><div>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.</div></div>","PeriodicalId":50806,"journal":{"name":"American Journal of Orthodontics and Dentofacial Orthopedics","volume":"167 1","pages":"Pages 29-38"},"PeriodicalIF":2.7,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142382235","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}

{"title":"Training, use, and modifications related to artificial intelligence in postgraduate orthodontic programs in North America","authors":"Joshua Hanenkrath ,&nbsp;Jae Hyun Park ,&nbsp;Curt Bay","doi":"10.1016/j.ajodo.2024.09.008","DOIUrl":"10.1016/j.ajodo.2024.09.008","url":null,"abstract":"<div><h3>Introduction</h3><div>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.</div></div><div><h3>Methods</h3><div>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).</div></div><div><h3>Results</h3><div>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%).</div></div><div><h3>Conclusions</h3><div>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.</div></div>","PeriodicalId":50806,"journal":{"name":"American Journal of Orthodontics and Dentofacial Orthopedics","volume":"167 1","pages":"Pages 89-94.e2"},"PeriodicalIF":2.7,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142632222","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}

{"title":"Trial sequential analysis: Reducing the likelihood of false-positive findings of meta-analyses","authors":"Yu-Kang Tu ,&nbsp;Fang Hua ,&nbsp;Nikolaos Pandis","doi":"10.1016/j.ajodo.2024.10.002","DOIUrl":"10.1016/j.ajodo.2024.10.002","url":null,"abstract":"","PeriodicalId":50806,"journal":{"name":"American Journal of Orthodontics and Dentofacial Orthopedics","volume":"167 1","pages":"Pages 127-132"},"PeriodicalIF":2.7,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142873399","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}

{"title":"January 2025 Continuing Education","authors":"Dr Allen H. Moffitt (CE Editor)","doi":"10.1016/j.ajodo.2024.11.003","DOIUrl":"10.1016/j.ajodo.2024.11.003","url":null,"abstract":"","PeriodicalId":50806,"journal":{"name":"American Journal of Orthodontics and Dentofacial Orthopedics","volume":"167 1","pages":"Pages 133.e1-133.e2"},"PeriodicalIF":2.7,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143140208","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}

{"title":"How environmentally friendly is the disposal of clear aligners? A gas chromatography-mass spectrometry study","authors":"Elbe Peter ,&nbsp;J. Monisha ,&nbsp;V.P. Sylas ,&nbsp;Suja Ani George","doi":"10.1016/j.ajodo.2024.08.011","DOIUrl":"10.1016/j.ajodo.2024.08.011","url":null,"abstract":"<div><h3>Introduction</h3><div>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.</div></div><div><h3>Methods</h3><div>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.</div></div><div><h3>Results</h3><div>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-.</div></div><div><h3>Conclusions</h3><div>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.</div></div>","PeriodicalId":50806,"journal":{"name":"American Journal of Orthodontics and Dentofacial Orthopedics","volume":"167 1","pages":"Pages 39-46"},"PeriodicalIF":2.7,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142331835","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}

{"title":"The periodontal ligament-periosteum sandwich hypothesis: A thought experiment on fenestrations and dehiscences","authors":"Greg J. Huang","doi":"10.1016/j.ajodo.2024.08.017","DOIUrl":"10.1016/j.ajodo.2024.08.017","url":null,"abstract":"<div><div>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.</div></div>","PeriodicalId":50806,"journal":{"name":"American Journal of Orthodontics and Dentofacial Orthopedics","volume":"167 1","pages":"Pages 3-6"},"PeriodicalIF":2.7,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142479954","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}

{"title":"Effects of curing lights on polymerization shrinkage of composite attachments in clear aligner treatment: A microcomputed tomography study","authors":"Irmak Ocak ,&nbsp;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/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.</div></div><div><h3>Results</h3><div>Significant differences (<em>P</em> &lt;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}

{"title":"Comparison of microbial adhesion and biofilm formation on different orthodontic aligners","authors":"Aylin Pasaoglu Bozkurt ,&nbsp;Mehmet Demirci ,&nbsp;Pelin Erdogan ,&nbsp;Emre Kayalar","doi":"10.1016/j.ajodo.2024.08.010","DOIUrl":"10.1016/j.ajodo.2024.08.010","url":null,"abstract":"<div><h3>Introduction</h3><div>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).</div></div><div><h3>Methods</h3><div><em>Streptococcus mutans</em> (ATCC 25175) and <em>Lactobacillus acidophilus</em> (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 <em>P</em> &lt;0.05.</div></div><div><h3>Results</h3><div>It was found that more bacterial formation occurred on ClearCorrect than on Smartee at 120, 168, and 240 hours (<em>P</em> &lt;0.05). It was observed more biofilm formation at 168 hours on Graphy than on Smartee (<em>P</em> &lt;0.05). It was found that <em>S mutans</em> + <em>L acidophilus</em> formed more biofilm at 120 and 168 hours on Graphy than on Invisalign (<em>P</em> &lt;0.05).</div></div><div><h3>Conclusions</h3><div>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.</div></div>","PeriodicalId":50806,"journal":{"name":"American Journal of Orthodontics and Dentofacial Orthopedics","volume":"167 1","pages":"Pages 47-62"},"PeriodicalIF":2.7,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142479936","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}

{"title":"Comparison of physical, mechanical, and optical properties between thermoplastic materials and 3-dimensional printing resins for orthodontic clear retainers","authors":"Siew Peng Neoh ,&nbsp;Anak Khantachawana ,&nbsp;Rochaya Chintavalakorn ,&nbsp;Peerapong Santiwong ,&nbsp;Toemsak Srikhirin","doi":"10.1016/j.ajodo.2024.06.010","DOIUrl":"10.1016/j.ajodo.2024.06.010","url":null,"abstract":"<div><h3>Introduction</h3><div>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.</div></div><div><h3>Methods</h3><div>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.</div></div><div><h3>Results</h3><div>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.</div></div><div><h3>Conclusions</h3><div>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.</div></div>","PeriodicalId":50806,"journal":{"name":"American Journal of Orthodontics and Dentofacial Orthopedics","volume":"167 1","pages":"Pages 95-109.e1"},"PeriodicalIF":2.7,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142873407","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Information for readers","authors":"","doi":"10.1016/S0889-5406(24)00491-8","DOIUrl":"10.1016/S0889-5406(24)00491-8","url":null,"abstract":"","PeriodicalId":50806,"journal":{"name":"American Journal of Orthodontics and Dentofacial Orthopedics","volume":"167 1","pages":"Page A8"},"PeriodicalIF":2.7,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143140894","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}