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Assessment of the effectiveness of invisible aligners compared with conventional appliance in aesthetic and functional orthodontic treatment: A systematic review
Abstract
To seek scientific evidence to support the effectiveness of invisible aligners, in the aesthetic and functional aspects, compared with that of conventional braces. An electronic search was performed with a complementary grey literature search for in vivo research. No language restrictions were applied. Scopus, PubMed, Web of Science, Cochrane, ClinicalTrials and GreyLiterature databases were used. Studies were first selected by title and abstract; those potentially eligible were read in full. Non‐randomized studies were assessed for risk of bias using the tools Methodological Index for Non‐randomized Studies (MINORS) and Cochrane Collaboration Common Scheme for Bias as a function of the presence of randomization. The search found 559 studies, of which 55 were potentially eligible. A total of 4 articles were included in this systematic literature review: three non‐randomized controlled studies and one randomized controlled study, three with low risk of bias (RoB) and one with moderate RoB. Three studies showed time of correction of dental crowding shorter or equal to that of the control group and only one study showed less time of correction using conventional braces. Invisible aligners were deficient with respect to anterior/posterior and vertical corrections compared with fixed orthodontic appliances. Invisible aligners are effective in promoting dental alignment, but present clinical limitations in relation to the conventional system.
... 6 Vertical movements pose greater challenges, [14][15][16]18,21 with maxillary anterior tooth extrusion being the least accurate. 18,22 Novel attachments may improve outcomes, with extrusion showing greater predictability than intrusion, particularly in anterior open bite cases. 13 Maxillary incisors may undergo unintended extrusion, whereas posterior teeth may be apically placed. ...
... CAT, clear aligner therapy; IPR, interproximal reduction CAT demonstrates effectiveness in aligning and straightening dental arches, particularly beneficial for mild to moderate crowding in non-growing patients compared with FAs. 15,18,22 However, if crowding exceeds 6 mm, the incisors may tend to procline and protrude after alignment with CAT. 14 The ability of CAT to modify intercanine, interpremolar, and intermolar widths is comparable to that of FAs and aids in resolving crowding. 14,22 However, arch expansion through bodily tooth movements remains a limitation according to some SRs. ...
... 15,18,22 However, if crowding exceeds 6 mm, the incisors may tend to procline and protrude after alignment with CAT. 14 The ability of CAT to modify intercanine, interpremolar, and intermolar widths is comparable to that of FAs and aids in resolving crowding. 14,22 However, arch expansion through bodily tooth movements remains a limitation according to some SRs. 13,14,24 In addition, CAT is noted to have an advantage in treating segmented tooth movements. ...
Expeditious strides in the fields of biomaterials, computer-aided design, and manufacturing have catapulted clear aligner therapy (CAT) to become a comprehensive orthodontic treatment modality. The efficiency of achieving planned tooth movement with clear aligners is a significant consideration while setting up the final treatment goals, as well as calculating treatment times and costs based on the available evidence. Contemporary research outcomes confirm that one of the most commonly reported clinical concerns with CAT is the discrepancy between the prescribed outcome in the digital treatment plan and the clinically achieved outcome from a given series of aligners. Inaccurate prediction of tooth movements may not only lead to a prolonged duration of aligner treatment with an additional need for refinement strategies; but it may also cause other concerns, such as patient burnout and increased potential for relapse. The authors of this paper have elucidated some of the critical elements that may help address this discrepancy between digitally prescribed and clinical outcomes based on an evidence-based approach with regard to the predictability and accuracy of CAT. A strong diagnostic acumen, judicious case selection, solid biomechanical understanding of various types of orthodontic tooth movements, a research framework that keeps pace with technological and material developments and provides evidence-based knowledge of the limitations of CAT; and above all, the ability of the clinician to continually innovate as per different clinical scenarios, all contribute to attaining treatment predictability, efficacy, and efficiency with CAT.
... Consequently, the accuracy of tooth movement prediction and the ability of clear aligners to effectively achieve major tooth and root movements compared to FAs are essential factors that need evaluation. While some studies and systematic reviews (SRs) have explored the accuracy and effectiveness of CAT [19][20][21][22][23][24][25][26][27][28][29][30][31][32][33][34][35][36], there is still no definitive answer to the question of whether CAT is as predictable and effective as fixed orthodontic appliances. This study aims to systematically assess existing scientific evidence through an overview of SRs to evaluate the predictability of tooth movements with CAT and compare treatment outcomes between CAT and FA. ...
... After the full-text assessment, 51 were excluded for various reasons, resulting in a total of 20 articles included in this overview. These included 18 SRs [19][20][21][22][23][24][25][26][27][28][29][30][31][32][33][34][35][36] and 2 RCTs [46,47]. The PRISMA flow diagram illustrating the literature screening and inclusion process is presented in Fig. 1. ...
... The effectiveness of CAT compared to conventional FAs was evaluated as the second major outcome in this overview, incorporating evidence from eight SRs of varying quality [21][22][23][24][25][26][27][28]. The clinical efficacy or effectiveness of clear aligners varied across different SRs due to various factors, including heterogeneous results from different study designs. ...
... Orthodontics has been one of the areas in Dentistry seeing rapid development. The use of aesthetic brackets, lingual orthodontic appliances, or clear aligners (CA) appeared to hide the use of metal brackets [1]. With regards to clear aligner treatment (CAT), the use of a planning software has allowed higher predictability. ...
... With regards to clear aligner treatment (CAT), the use of a planning software has allowed higher predictability. However, some of the main disadvantages of these treatments are the limited control of root movement and intermaxillary correction [1]. ...
... The most mentioned limitation in the literature refers to CAT as less effective in achieving occlusal contacts than fixed appliances. Controlling the buccolingual tipping of posterior teeth is also difficult, due to the creation of an artificial interference linked to the use of the CA, referred as "bite-block effect" in the literature [1,7,8]. The failure to achieve stable and solid occlusal contacts has been discussed as one of the reasons for the higher relapse rate associated with CAT [1,7]. ...
Background:
Clear aligners (CA) are used 22 h daily, creating a bite-block effect. This work aims to (i) analyze occlusal changes before the beginning of treatment, after the first set of CA and after the use of additional aligners; (ii) compare planned occlusal contacts with the ones obtained after the first set of CA; (iii) analyze the occlusal changes occurred after reaching the orthodontic goals after 3 months of using CA only at night; (iv) evaluate and characterize which tooth movements did not allow the treatment to be completed at the end of the first set of aligners, and finally (v) verify the possible relation between the changes in occlusal contact and areas and parameters such as case complexity and facial biotype.
Materials and methods:
A quantitative, comparative, and observational longitudinal cohort study design was implemented to evaluate the clinical data and the complexity levels of cases receiving CA. A non-probabilistic and convenience sample of 82 individuals was recruited. The orthodontic malocclusion traits were classified as simple, moderate, or complex corrections based on the basis of the Align® recommendations with the Invisalign® evaluation tool. According to the Invisalign® criteria, patients need only one complex problem for their case to be classified as complex. Meshlab® v. 2022.02, ClinCheck® version Pro 6.0, My-Itero® version 2.7.9.601 5d plus, and IBM® SPSS Statistics software (Statistical Program for Social Sciences), version 27.0 for Windows were the software® used.
Results:
A statistically significant decrease in area and occlusal contacts number were observed from before the start of orthodontic treatment (T0) to the end of treatment (T1). The changes in the occlusal area (from T0 to T1) were statistically different between hyperdivergent (28.24 [15.51-40.91]) and hypodivergent (16.23 [8.11-24.97]) biotypes (p = 0.031). A significant difference between the hyperdivergent (4.0 [2.0-5.0]) and normodivergent (5.5 [4.0-8.0]) group was found in T1 for the anterior contacts (p = 0.044). Anterior contacts obtained were significantly higher than the planned (p = 0.037) Between T1 and T2 statistically significant increases of occlusal areas, posterior and total contacts were observed.
Conclusions:
Occlusal contact and area were decreased, either at the end of the first set or after the use of additional aligners. Anterior occlusal contacts obtained were higher than planned as opposed to posterior occlusal contacts obtained. The hardest tooth movements to achieve to complete the treatment were distalization, rotation, and posterior extrusion. After completing orthodontic treatment (T1) to 3 months after (T2) using additional aligners only at night, posterior occlusal contacts were significantly increased, which could be due to the natural settling of the teeth in this period.
... It had been concluded that CAT is effective for mild to moderate cases of malocclusion in patients where simple tooth movement is required without the need of bodily/root movement and/or extraction, while, it is not as successful as fixed appliances for more severe crowding and complex cases, especially when extractions are included [24,27,29]. Generally, in minor cases (without extraction), aligners can increase arch perimeter, but in severe crowding (greater than 6 mm), this can result in significant incisor proclination and protrusion which is neither desirable nor stable [24,30]. ...
... With aligners these movements, especially extrusion can be difficult to achieve. Besides, the presence of aligner material that covers the occlusal surfaces of the teeth as a physical barrier prevents adequate settling of the teeth during the finishing stage of treatment [25,27]. This could explain the inability of CAT to establish adequate occlusal contacts, as found by several reviews [24][25][26]30]. ...
... It was evident from the literature that there is limited control of rotational tooth movement with CAT for canines and premolars. This may be related to the difficulty in applying a force couple system on a round surface with an aligner [43,45], but the use of IPR, attachments (vertical ellipsoid, centrally located) [45], overcorrection, and reduced staging to less than 1.5˚/aligner can improve CAT ability to deliver such movement [24,27,29,30]. ...
Objective
To evaluate the available evidence regarding clinical effectiveness of clear aligner treatment (CAT).
Materials and methods
A comprehensive literature search was conducted for systematic reviews investigating effectiveness of CAT published up to July 15, 2021. This was accomplished using different electronic databases. No language restriction was applied. Screening, quality assessment, and data extraction were performed by two authors independently. Information was categorized and narratively synthesized for the key findings from moderate and high-quality reviews.
Results
A total of 361 potentially eligible reviews were identified. After excluding the non-relevant/low-quality reviews, 18 systematic reviews were included. CAT was found to be effective for mild to moderate malocclusions, and was associated with inferior outcomes when treating severe cases or with achieving specific tooth movements. There were conflicting results regarding treatment duration; however, CAT may be associated with shorter treatment in mild to moderate cases. Relapse was greater with CAT, while periodontal health was better. The risk of root resorption tended to be lower with CAT. Regarding pain, the results were unclear, although CAT was found to be more comfortable and associated with a reduced impact on eating and chewing.
Conclusions
The level of evidence regarding CAT is moderate; hence, further high-quality randomized clinical trials are required. Evidence supports use of aligners as an alternate to fixed appliances in patients with mild-to-moderate malocclusion but not in severe cases. Advancement in technology could enhance the accuracy of CAT in delivering planned outcomes.
Clinical relevance
CAT can be used effectively for selected cases with mild to moderate malocclusion.
Registration
PROSPERO registration number: CRD42021246855.
... It is a treatment generally performed sequentially for 20 to 22 hours with gradual and successive changes of the device every seven to 14 days 4 . The use of invisible orthodontic appliances to treat malocclusions has seen a considerable increase, mainly among adults seeking a more discreet treatment, which may include transparent brackets, lingual devices or aligners 5 . ...
... Furthermore, aligners are effective in cases of mild crowding, overbite, or when there is recurrence of previous orthodontic treatment. However, their limitations require overcorrection and the use of auxiliary devices 5,8 . Therefore, aesthetic aligners may be an effective alternative to traditional appliances, but they are not applicable to all clinical situations yet. ...
Objective: To investigate, through a survey of studies, the impact on quality of life and oral health as well as the effectiveness of orthodontic aligners compared to conventional fixed appliances. Methodology: To compose this integrative review, studies published in the PubMed/Medline, Lilacs, Scielo and Scholar Google databases from 2019 to 2024 were included, which were aligned with the theme and full text availability. Editorials, posters, duplicate articles, monographs, book chapters were excluded from the sample. The descriptors used were: aesthetic aligners; clear aesthetic aligners; biomechanics; effectiveness; quality of life; and oral health. Results: A total of 800 studies were identified, which 584 were from the last five years. Eighty-six papers were selected for full reading; however, 61 did not meet the scope of this study and five were not available in full text, being excluded. After applying the eligibility criteria, 20 studies remained to be part of this review. Conclusion: Aligners are a good alternative in less complex malocclusions when aesthetics and shorter treatment duration are important. Regarding quality of life and oral health, there are no significant differences between invisible and conventional orthodontics; however, aligners can contribute to better biofilm control, favoring periodontal health.
... This study investigated general practitioners' and orthodontists' knowledge of Invisalign treatment. Apart from the importance of patient cooperation in clear aligner treatment, a low-to-moderate risk of bias literature indicates that clear aligners present challenges in optimal movement of teeth with short clinical crowns, correcting severe deep bite and premolar extraction cases, correcting diastemas and dental crowding of more than 5 mm, and achieving optimal root parallelism, torque control and occlusal contacts [15][16][17][18][19][20]. ...
... This study also found no differences between general practitioners and orthodontists on the question of whether Invisalign treatment can result in a shorter treatment duration or involves a fewer number of visits than conventional fixed appliances. In terms of the treatment duration and number of visits for Invisalign and conventional fixed appliances, previous meta-analyses have shown contradictory and insignificant results [9,20,24]. However, a recent randomized clinical trial by Lin et al. [25] showed a longer treatment duration (approximately 4.8 months) with Invisalign clear aligners than conventional fixed appliances for mild malocclusions, while a recent retrospective study found Invisalign aligners and conventional fixed appliances resulted in a similar treatment duration for adults with severe deep bite [26]. ...
Purpose
This study investigated the knowledge differences between general practitioners and orthodontists about the Invisalign system.
Materials and methods
A web-based survey regarding 10 Invisalign treatment domains was distributed to 161 orthodontists and 213 general practitioners. The responses were ranked using a Likert-type scale and analysed with the Chi-square test and Bonferroni adjustment.
Results
The response rate was 52.1% for general practitioners and 63.4% for orthodontists. Comparing Invisalign to conventional fixed appliances, orthodontists agreed/strongly agreed that Invisalign aligners are suitable for all types of cases (p = 0.001). Orthodontists also agreed that it causes less tooth discomfort (p = 0.01) and an increased number of attachments can affect its esthetic perception (p = 0.014) but general practitioners opted for the ‘Do Not Know’ option (p ≤ 0.01). General practitioners also responded ‘Do Not Know’ to whether Invisalign treatment finishes in a shorter duration (p = 0.001), achieves all types of tooth movement (p < 0.001) and results in better periodontal health (p = 0.001). Orthodontists were more likely to disagree/strongly disagree that Invisalign treatment results in less tooth root resorption (p = 0.008), better American Board of Orthodontics Objective Grading System and Peer Assessment Rating scores (p < 0.001) and low risk of relapse (p < 0.001), while general practitioners opted for the ‘Do Not Know’ option (p < 0.0001, p < 0.0001 and p < 0.0001, respectively).
Conclusion
Regarding Invisalign treatment, this study found that orthodontists were generally evidenced-based but general practitioners lacked such knowledge, suggesting that general practitioners must be provided with relevant evidenced-based information.
... Additionally, tele-orthodontics would be greatly advantageous for orthodontic treatment based on a virtual setup because it is possible to reduce simple controls while keeping important appointments, such as stripping, bracket/attachment or auxiliary placement, extraction, et cetera [27,28]. Reducing the number of clinical appointments increases the efficiency of the treatment which is a main concern for both patients and clinicians [29,30]. These assumptions have been recently confirmed by a recent study showing that subjects underwent clear aligners therapy, and the Dental Monitoring system required fewer number of appointments (about 23%) compared to the unmonitored group. ...
... The extra-alveolar region has been recommended Additionally, tele-orthodontics would be greatly advantageous for orthodontic treatment based on a virtual setup because it is possible to reduce simple controls while keeping important appointments, such as stripping, bracket/attachment or auxiliary placement, extraction, et cetera [27,28]. Reducing the number of clinical appointments increases the efficiency of the treatment which is a main concern for both patients and clinicians [29,30]. These assumptions have been recently confirmed by a recent study showing that subjects underwent clear aligners therapy, and the Dental Monitoring system required fewer number of appointments (about 23%) compared to the unmonitored group. ...
Background: Reverse engineering (RE) or back engineering is a process that analyzes a physical object to obtain the primary data of the same project. RE technologies have different applications in industrial settings and productive chains; however, with the advent of digital technologies in dentistry and orthodontic fields, they are involved in the new diagnostic and clinical digital workflow. For example, 3D model scanning, 3D facial scanning, models superimposition, digital orthodontic setup, anatomical volumetric assessment, soft tissue analysis, orthodontic digital guided systems, and prototyped orthodontic appliances represent a few examples of the application of RE in orthodontics. Moreover, clinicians can manipulate the data derived from original digital file to enhance diagnosis and communication with other clinicians and dental technicians; however, RE and digital technologies systems are not exempt from shortcomings, including costs and knowledge curve. In this regard, the aim of the present manuscript was to describe the use of reverse engineering technologies in modern digital orthodontics and provide helpful information for those specialists who are at the beginning of the transition from analogic to digital orthodontic workflow.
... Only one study of grade A (3.9%) had a level of evidence of 1b. [12] 2b B [18] 2a B [6] 1b A [19] 2a B [20] 2a B [21] 2a B [9] 2b B [8] 2b B [5] 2b B [22] 2a B [14] 2b B [11] 2b B [10] 2b B [17] 2b B [23] 2a B ...
... Adequate occlusal contacts are difficult to achieve with aligners. A systematic review by Pithon et al., [19]. Clearly explained the difference in the OGS score in the occlusal contact. ...
Background: Over the years, aligner therapy has undergone a great evolution. The use of aligners is now an alternative to braces for aesthetic reasons. Their effectiveness and impact have yet to be evaluated. Objective: The objective of this study was to compare the effectiveness of dental movements with aligners versus the use of conventional appliances, as well as the effectiveness and impact on periodontal health and root resorption. Materials and Methods: A systematic search of PubMed, Ebsco Host and Scopus was performed using a well-designed formula. Articles published in the last 10 years in English and French were included after filtering the titles, abstracts then full texts. Results: Twenty-six records were deemed suitable for the objectives of our systematic review. All records focused on the comparison of treatment with aligners and fixed appliances. The difference in treatment and time efficiency was assessed in 17 papers, 6 papers evaluated the impact of orthodontic appliances on periodontal health, and the remaining 3 records focused on the occurrence of root resorption. Conclusion: Clear aligners produce clinically acceptable outcomes that could be comparable to fixed appliance therapy. Aligners facilitate oral hygiene practices which results in better periodontal health. However, it appears that Invisalign may not be as effective as fixed appliances in achieving certain tooth movements like vertical, radicular and rotational movements.
... With the increasing demand for aesthetic and comfortable orthodontic solutions, clear aligner treatments have gained widespread popularity, particularly among adult patients [1,2]. Although clear aligners have a wide range of applications and improved significantly, the mechanical properties of clear aligners remain a limiting factor for achieving complex tooth movements [3,4]. Additionally, traditional thermoformed aligners are associated with time and cost inefficiencies and dimensional instability [5,6]. ...
Background
The mechanical properties of directly 3D-printed clear dental aligners are currently constrained by the limitations of available 3D printing materials. This study aimed to investigate the mechanical properties of direct 3D-printed clear resin embedded with orthodontic wire under different surface treatments to propose a novel integration method for orthodontic appliances and treatment.
Methods
The stainless-steel wires were divided into three groups based on surface treatments: control groups (C), sandblasting group (S), sandblasting and acid etching group (SA). Surface characteristics were analyzed and interfacial shear strength (IFSS) was measured. Dumbbell-shaped specimens were fabricated using 3D-printed clear resin and divided into four groups, depending on whether they were embedded with stainless-steel wires subjected to different surface treatments. The static and dynamic mechanical properties tests were carried out to calculate elastic modulus, tensile strength, and stress relaxation.
Results
The average roughness and surface morphology of stainless-steel wires exhibited significant differences ( P < 0.001) following different surface treatments. Sandblasting and acid-etching significantly enhanced IFSS, resulting in a fivefold increase to 28.8 MPa. The elastic modulus and tensile strength of the 3D-printed resin embedded with wires were significantly higher than those of the pure 3D-printed resin group. However, no significant differences in elastic modulus were observed among the different wire surface treatment groups. The sandblasting and acid-etching group exhibited higher residual stress compared to the other groups during both 6-hour and cyclic stress relaxation tests.
Conclusion
This study presents a novel approach to 3D-printed clear dental aligners integrated with metal wires for orthodontic treatment. Surface treatment of orthodontic metal wire through sandblasting and acid etching enhances the bonding strength between the wire and 3D-printed clear resin, improving the static and dynamic mechanical properties of directly 3D-printed clear resin appliances. The innovative process and device provide an integrated solution for digital orthodontic treatments.
... A recent survey indicated that clear aligner therapy was provided by more than 90% of orthodontists (Meade and Weir, 2022). Compared with fixed appliances, clear aligners offer several advantages, including aesthetics, comfort, and ease of oral hygiene maintenance, thereby improving the quality of life of patients (Pithon et al., 2019;Li et al., 2023;Liu et al., 2024). Despite the numerous advantages of clear aligners, they still suffer from poor tooth control when performing complex tooth movements because of their material properties (Kravitz et al., 2009;Simon et al., 2014). ...
Objectives
This study established three-dimensional finite element models to explore the impacts of surface wear of attachments on maxillary canine distalization with clear aligners, thereby guiding the clinical application of attachments and enhancing the efficiency of clear aligner therapy.
Materials and methods
Finite element models of maxillary canine distalization, including the maxilla, dentition, periodontal ligament, attachments (in both initial and worn states), and clear aligners, were established. Two groups of attachments (vertical rectangular attachment and optimized root control attachment) and five working conditions representing different degrees of attachment wear (M0, M2, M4, M6, and M8) were designed for canine distalization. Tooth displacement and equivalent stress in the roots and periodontal ligaments were analyzed.
Results
The canines in both groups exhibited a tipping movement pattern under all working conditions. By M8, the distal displacement of the canine crown, the equivalent stress values in the roots, and the equivalent stress values in the periodontal ligaments in the rectangular attachment group decreased by 12.04%, 30.80%, and 16.48%, respectively, compared to M0. In the optimized root control attachment group, these values decreased by 24.98%, 34.69%, and 19.15%, respectively. However, under all working conditions, the canines in the rectangular attachment group presented greater displacement and stress. The greatest reduction in canine crown distal displacement and stress values was observed between M6 and M8 in the rectangular attachment group, but the efficiency of canine distalization was still 64.30% at M8, with minimal change. In the optimized root control attachment group, the greatest reduction was observed in M4–M6, and the efficiency of canine distalization decreased to less than 60% in response to M6.
Conclusion
The canines tended to tip when maxillary canine distalization was performed with clear aligners. Attachment wear led to a reduction in the efficiency of canine distalization. Compared with optimized root control attachments, the impact was less significant for rectangular attachments. Once optimized root control attachments have been in place for more than 4 months and maxillary canine distalization is still required, orthodontists should closely monitor the wear of these attachments. If necessary, timely restoration or rebonding of the attachments is recommended.
... 38 Regarding comparative articles, the overall quality score was categorised as follows: 0-6=very low quality; 7-12=low quality; 13-18=moderate quality and 19-24=high quality. 39 ...
Objectives
To examine sex differences in psychological readiness to return to sport following anterior cruciate ligament (ACL) reconstruction as well as to determine whether males and females separately fulfilled cut-off values (≥65) of psychological readiness necessary to return to sport.
Information sources
Web of Science, Scopus and PubMed were comprehensively searched from inception to January 2024 to identify relevant studies.
Eligibility criteria
Observational investigations that compared males and females with a history of ACL reconstruction concerning psychological readiness to return to sport.
Risk of bias
Studies were rated using the Methodological Index for Non-Randomised Studies.
Included studies
Only 11 reports fulfilled the eligibility criteria and were included in the quantitative analysis. A total of 2618 participants were subjected to the primary ACL reconstruction, out of 1631 males and 987 females. Psychological readiness to return to sport was evaluated approximately 9±2.9 months following surgery.
Synthesis of results
The main findings demonstrated that males had slightly higher psychological readiness to return to the sport than females (standardised mean difference 0.33; 95% CI 0.14 to 0.52; p=0.0007; I ² =77%) after ACL surgery. In addition, the mean psychological readiness to return to the sport of males was 70.1±8.8 points and of females 65.1±8.8 points, indicating that both sexes exceeded recommendations necessary to return to sport.
Conclusion
Males had slightly higher psychological readiness to return to sport than females approximately 9±2.9 months after ACL reconstruction and both sexes exceeded the highlighted recommendations necessary to return to sport.
PROSPERO registration number
CRD42024497769 : https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42024497769 .
... The utilization of clear aligners in orthodontic treatment has significantly increased over the past two decades, driven by the growing demand for aesthetically pleasing orthodontic solutions [1][2][3]. Aligners, lauded for their aesthetic superiority over conventional braces, have become a preferred choice for patients who seek an inconspicuous method for correcting malocclusions [4,5]. The appeal of these aligners lies in their transparency, which allows patients to undergo orthodontic treatment without the stigma often associated with metal braces, thereby not only enhancing the patient's appearance during treatment but also boosting self-confidence [6]. ...
The significant rise in the use of clear aligners for orthodontic treatment is attributed to their aesthetic appeal, enhancing patient appearance and self-confidence. The aim of this study is to evaluate the aligners’ response to common staining agents (coffee, black tea, Coca-Cola, and Red Bull) in color and chemical stability. Polyurethane-based thermoformed and 3D-printed aligners from four brands were exposed to common beverages to assess color change using a VITA Easyshade compact colorimeter after 24 h, 48 h, 72 h, and 7 days, as well as chemical stability using ATR-FTIR spectroscopy. The brand, beverage, and manufacturing method significantly influence color stability. ATR-FTIR analysis revealed compositional differences, with variations in response to beverage exposure affecting the integrity of polymer bonds. Color change analysis showed coffee as the most potent staining agent, particularly affecting Tera Harz TC85 aligners, while ClearCorrect aligners exhibited the least susceptibility. 3D-printed aligners showed a greater color change compared to thermoformed ones. Aligners with a PETG outer layer are more resistant to stains and chemical alterations than those made of polyurethane. Additionally, 3D-printed polyurethane aligners stain more than thermoformed ones. Therefore, PETG-layered aligners are a more reliable choice for maintaining the aesthetic integrity of aligners.
... As the popularity of clear aligner systems continues to increase, there is still some uncertainties about their effectiveness [7]. While clear aligners are being used for more and more complex cases, they still cannot treat all types of malocclusions [8]. Clear aligners are effective in treating mild to moderate crowding or spacing, posterior expansion, lower incisor extraction cases, and distal tipping of molars, intrusion of one or two teeth; however, they are not as equally effective in more difficult movements, such as extrusion, correction of severe rotations, molar uprighting, and closure of extraction spaces, which are known to be more difficult to achieve with aligners [7]. ...
Background: Orthodontic treatments aim to enhance dental aesthetics, functionality, and long-term oral health. Clear aligners have gained popularity as an aesthetic and convenient option for patients seeking orthodontic correction. However, the quality and readability of online Arabic patient-centered information regarding clear aligners has not been studied yet. The aim of our study is to investigate the quality and readability of Arabic patient-centered information about clear aligners.
Methods: We conducted an extensive evaluation of Arabic web-based content pertaining to clear aligners using three prominent search engines. Eligible websites were categorized based on specialization, organizational affiliation, material type, and presentation style. We assessed website quality and reliability using the DISCERN instrument, Journal of American Medical Association (JAMA) benchmarks, and Health on the Net (HON) code. In addition, we measured readability using the Flesch Reading Ease Score (FRES), Simplified Measure of Gobbledygook (SMOG), and Flesch-Kincaid Grade Level (FKGL).
Results: Out of 600 search results, 195 websites met the inclusion criteria. None of the websites were HON-code accredited. DISCERN assessments revealed low content quality, with none of the websites achieving high-quality status. The JAMA benchmarks showed limited compliance with the four items, with currency being the most frequently achieved. Readability assessments indicated generally high readability, with FKGL scores suggesting easy comprehension for the average readers.
Conclusion: While Arabic web-based information on clear aligners is highly readable, its credibility and quality require significant improvement. Websites should adhere to medical information standards, subject content to rigorous assessments, and seek accreditation to ensure reliability. Enhancing the accessibility and comprehensibility of health-related content will empower individuals to make informed health decisions. Addressing limitations, such as social media and video content evaluation, and conducting comparisons with English websites in future research will provide a more comprehensive understanding of the landscape of online orthodontic information.
... They are also a good option for patients who are concerned about the appearance of traditional metal braces or who have active lifestyles and need a more discreet orthodontic option. [66][67][68][69][70] In general, CAT is indicated in cases of mild crowding or spacing issues between 1 mm and 5 mm; deep overbites; dental arches that are too narrow and require expansion; intrusion of one or two teeth; severe crowding, if the lower incisor gets extracted; and any molars that needed to be tilted in distal direction. [71] CAT has been successfully used for the treatment of anterior crossbite in two 8-year-old children; the procedure took five months and was able to completely correct the problem in either case, without any further problems or discomfort, suggesting that CAT may be especially useful in growing teeth which still have enough flexibility to become realigned. ...
The advantages of Clear Aligners Therapy (CAT) include the braces being virtually invisible, comfortable to wear, and removable for eating and brushing; that way, CAT can be used to treat a wide range of orthodontic issues. In 1999, the company Align Technology introduced the frst commercial clear aligner system called Invisalign. The Invisalign system was initially only available to orthodontists, but later became available to general dentists as well. The system quickly gained popularity among patients who were looking for a more discreet and comfortable alternative to traditional braces. In 2000, Align Technology received FDA clearance for the Invisalign system, which further increased its popularity. The biomechanics of clear aligners involve the use of custom-made tooth aligners that are specifcally shaped to guide teeth into desired positions. These aligners are typically made from flexible materials such as polyurethane or ethylene vinyl acetate and are adjusted to apply the necessary forces for tooth movement. Attachment devices, such as power ridges or buttons, are often used to enhance or assist in specifc tooth movements and for retention of the aligner. The use of attachments allows for the exertion of desired force on the teeth, which is crucial for the success of Clear Aligner Therapy. CAT should be used if patients are concerned about the esthetic appearances of their teeth—for example, actors and other individuals that rely on their appearances in public in a professional context—and if the misalignment is not severe, so that clear aligners can still work. One should not use CAT in cases of severe crowding or spacing issues that require extractions. If the patient has complex jaw discrepancies or skeletal issues or if teeth need to be moved extensively in multiple directions, CAT is likely not going to be strong enough. In conclusion, Clear Aligner Therapy is a safe, effective, and convenient orthodontic treatment option that offers patients a virtually invisible way to achieve a straighter, more beautiful smile. With continued advancements in technology and a growing body of research supporting its effectiveness, the future of Clear Aligner Therapy looks bright.
... The aesthetic and comfort advantages, as well as the ease of cleaning, are points in favor of aesthetic aligners when compared to conventional fixed orthodontic appliances [6][7][8][9][10][11][12]. Disadvantages related to the use of clear aligners include limited control root movement, limited intermaxillary correction, little or no control by the operator and full-time dependence by the patient, with the appliance being removed only for eating and sanitation [13]. ...
Coronal torque is one of the key factors in orthodontic treatment. An adequate torque value has an impact on aesthetics and soft tissue profile. The aim of this quantitative, comparative and observational longitudinal cohort study was to analyze the efficacy of the maxillary central incisor coronal torque in the Invisalign® system and evaluate the relation between coronal torque movement and patient’s facial biotype. In total, 27 patients were selected. The planned movements (TP) were obtained from the Invisalign Doctor Site® using mathematical formulas that consider the T0 measurements. Pre-treatment (T0) and after full use of the first set of aligners (T1) scanners were evaluated using Geomagic® Control X TM by superimposing T0 and T1 models using a transverse plane and the long axis of the tooth crown. IBM® SPSS® software was used for statistical purposes. We found statistically significant differences between T0 and T1 in pro-inclination and retro-inclination, as well as between achieved and planned values in pro-inclination (p = 0.011). We verified that hyperdivergent clinical cases presented higher mean values of coronal torque, and hypodivergent cases presented lower values. In pro-inclination, the differences between the planned and achieved values were greater in hypodivergent cases and smaller in hyperdivergent cases. In retro-inclination, the differences between the planned and achieved values were greater in normodivergent cases and smaller in hypodivergent cases. This study highlights that inefficacy is more accentuated in pro-inclination. Aligners are an effective tool for producing coronal repercussions of torque movement, being more effective in retro-inclination.
... Clear aligners are invisible tooth braces used for curing malocclusions and temporomandibular defects, as shown in Fig. 2. It is an excellent option compared to conventional tooth braces made of wires due to transparency and reduced time to cure the misaligned teeth (Pithon et al., 2019). Initially, EX30 material is used to fabricate the clear aligners with the assistance of the Stereolithography Apparatus (SLA), and for the enhancement of the surface quality, a five-axis CNC is used (Pugalendhi et al., 2019). ...
Additive Manufacturing (AM) processes have ample advantages compared to traditional manufacturing processes, including mass customization, material efficiency, bioprinting, and fabrication of complex geometries with reduced lead time. Despite such benefits, it suffers most from staircase effects that deteriorate the fabricated part's surface quality. Nowadays, additively manufactured aligners are suitable for treating malocclusion and temporomandibular defects of teeth. Fused Deposition Modelling (FDM) is one of the best substitutes for clear aligners production to reduce per-unit cost. Glycol-modified Polyethylene Terephthalate (PETG) is opted as the material to fabricate the clear aligners due to its biocompatibility and non-toxicity. However, the poor surface quality of the additively manufactured is a major challenge in developing clear aligners with the FDM. A novel experimental setup is designed and developed to enable Chemical Vapor Smoothing (CVS) to enhance the surface quality of the clear aligners. Furthermore, based on the Surface roughness, the comparison is made between the surface quality polished with various chemicals (namely methylethylketone (also known as 2-butanone), toluene and, cyclohexanone). Moreover, Response Surface Methodology (RSM) is used to analyze the impact of different process parameters (i.e., the chemical volume, exposure time, and workpiece orientation) on the surface quality of the clear aligners. Moreover, RSM shows that the impact of the clear aligners orientation on %ΔRa during the CVS is higher than other process parameters. Results demonstrate that cyclohexanone produces more uniform surface quality with a 92.73% reduction in surface roughness compared to methylethylketone and toluene on PETG, i.e., 89.66% and 88.63%, respectively. The developed surface finishing method is capable of producing uniform, smooth surfaces over the FDM-fabricated PETG clear aligners.
... The fact that all three groups in the study predominantly preferred conventional or self-ligating metallic brackets in terms of treatment success shows that there is a consensus that successful orthodontic treatment can be achieved with the best-known classical methods. 20 Additionally, considering this result, it can be said that while the orthodontists trust clear aligner in terms of esthetics and advantage/disadvantages, they do not trust them enough regarding treatment success. Also, according to the results of our study, clear aligners were more preferred for short-term treatments in all groups, while CMBs were more preferred for long-term treatments, supporting our viewpoint on this matter (Table 2). ...
Objective:
The aim of this study was to evaluate orthodontic treatment method preferences among dentistry students, dentists and orthodontic residents taking into account factors such as esthetics, advantage/disadvantage, cost and treatment duration.
Methods:
The study was carried out on three groups: dentistry students (n=318), dentists (n=110) and orthodontic residents (n=98), and a 17-question survey was applied. Questionnaire forms included informational photos of conventional metal brackets (CMB), esthetic ceramic brackets (ECB), self-ligating brackets (SLB), clear aligner (CA), and lingual brackets (LB). The participants' preferences for orthodontic treatment methods were evaluated using chi-square analysis, not only between groups but also considering gender and income level.
Results:
Regarding esthetics, dentists (41%) and orthodontic residents (78%) mostly preferred CA, while dentistry students mostly preferred LB (44%). With regard to advantage/disadvantage, dentistry students (31%) and dentists (39%) mostly preferred SLB, while orthodontic residents mostly preferred CA (55%). Regarding the success of the treatment, all three groups mostly preferred CMB. (respectively 50%; 47%; 72%). While CA was mostly preferred for short-term treatments in all three groups (respectively 40%; 71%; 88%), CMB was mostly preferred for long-term treatments (respectively 35%, 51%, 55%). Gender and income-level differences had little effect on orthodontic treatment method preferences.
Conclusion:
Except for long-term treatments and treatment success, there was generally great interest in CA, especially among orthodontic residents. Ceramic brackets and LB were generally the least preferred treatment methods among dentistry students, dentists, and orthodontic residents.
... In the 1960s, stainless-steel brackets were introduced; lingual brackets were preferred until the 1980s, when toothcolored ceramic brackets were introduced, and ceramic brackets and clear aligners are now in use [1][2][3][4]. However, there are significant advantages for metal brackets in certain cases over clear aligners due to their mechanical properties and tooth movement biomechanics [5][6][7]. This includes premolar-extraction cases that require bodily movements of molars and/or anterior teeth, which is challenging to achieve using clear aligners [8]. ...
This study provides valuable insights into the cosmetic impact of orthodontic appliances on job-hiring prospects in Saudi Arabia. Both ceramic braces and clear aligners are considered cosmetic corrective devices compared to traditional metallic braces. This survey-based, cross-sectional study used two models, one male, and one female. Four standardized smiling frontal photographs were taken for each model: one without any appliance and three with different orthodontic appliances (i.e., metal braces, ceramic braces, and clear aligners). The photographs of each model were shown to potential employers, followed by three questions for each photo to assess the employers' views on the applicants' professionalism, communication skills, and the likelihood of being hired. The survey was distributed via an electronic questionnaire to employers in Saudi Arabia, collecting feedback from 189 participants. The sample was collected from October 2022 to February 2023. The models' scores while wearing metal and ceramic bracket appliances were significantly lower than when the models were wearing clear aligners or were not wearing any appliance in each domain. In conclusion, orthodontic appliances have cosmetic implications that affect job-hiring prospects, with a higher chance of being hired if the candidate does not have an orthodontic appliance.
... With the advent of Invisalign®, the use of aligners was indicated for treating mild to moderate degrees of crowding, mild to moderate spaces, correction of dental flaring and tipping, and for relapsed cases treated previously using fixed appliances [13]. Over time, the range of the treated cases with clear aligners has expanded from the treatment of simple orthodontic cases to more complex cases such as treatment of anterior open bite [14], bimaxillary protrusion [15], excessive facial height, and severe dental crowding [16]. ...
This systematic review aimed to critically assess the available evidence regarding the effectiveness and efficiency of clear aligners in the comprehensive treatment of complex cases accompanied by premolars extraction. An electronic literature search by two reviewers was independently done on 27 February 2023 in the following databases without time and language limitations: Pubmed®, Scoups®, Google Scholar, Cochrane Library database, Web of Science™, and Proquest Database Open. Randomized controlled trials (RCTs) of any type, non-randomized clinical trials (CCT), cohort studies, and prospective, retrospective, and cross-sectional studies were reviewed. The risk of bias in included studies was assessed using the Risk of Bias (RoB 2.0) tool for randomized trials and the Risk of Bias in Non-randomized Studies (ROBINS-I) tool for non-randomized studies. After carefully searching the literature, six trials were included in this systematic review, three RCTs, two retrospective cohort studies, and one CCT. Two hundred eighty-three patients were included (186 females, 97 males). Three studies found that there were no differences between the clear aligners and fixed appliances when evaluations were done using the American Board of Orthodontists Objective Grading System (ABO-OGS) or the Peer Assessment Rating (PAR) index. Two studies found that there were some differences between predicted and achieved tooth movements when clear aligners were used in premolars extraction cases. Based on the included studies, the duration of treatment was shorter with fixed appliances than the clear aligners when applied to orthodontic extraction cases. Both clear aligners and fixed appliances were found effective in the orthodontic treatment of premolar extraction-based cases. Fixed appliances have the advantage of achieving better buccolingual inclination and occlusal contacts in a shorter treatment duration. Treatment with clear aligners might be associated with differences between predicted and achieved tooth movements. Therefore, the characteristics of these techniques should be considered when making a treatment decision.
... Fixed orthodontic treatment is still the best and most common choice for treating different types of malocclusions [1][2][3][4]. Although the effectiveness of traditional brackets has been recognized worldwide, this therapeutic method still has some disadvantages. ...
Orthodontic treatment with fixed devices should only be indicated in case of a stable, non-active periodontal disease status. Throughout orthodontic treatment, a careful assessment of the periodontal status is advised. Due to its anti-inflammatory and antimicrobial effects, laser therapy is frequently used as an adjunct to classic periodontal therapy. The aim of this study was to evaluate the advantages and limitations of the use of laser therapy on periodontal status during orthodontic treatment. Throughout the 9 months during which this placebo-controlled, single-blind clinical trial was conducted, 32 patients were included in the study, divided into two groups: microscope “+” (patients who observed the bacteria within the dental plaque-sample examination on the screen of a dark-field microscope in real time) and microscope “−” (patients who did not see the oral pathogens using a dark-field microscope). For all patients, using the split-mouth study design, laser therapy was applied to one hemiarch (HL), whereas the other hemiarch received treatment without active light (HC). After one month, by analyzing the main indicators of periodontal health status, we found that the plaque index (PI) and bleeding on probing (BOP) values were significantly decreased after receiving treatment (for PI: HL-p = 0.0005, HC-p = 0.0297; for BOP: HL-p = 0.0121, HC-p = 0.0236), whereas the probing-depth (PD) values remained almost the same as before treatment (HL-p = 1.5143; HC-p = 1.4762). Conclusions: The use of the dark-field microscope proved to be beneficial in sensitizing patients to the presence of bacteria in the oral cavity and motivated them to strictly follow the rules of oral hygiene. Laser treatment can be a valuable aid in periodontal therapy, but only in adjunction with mechanical therapy.
... However, prior meta-analyses have failed to identify significant differences in treatment duration between clear aligners and traditional braces. [12,25,26] Nonetheless, a recent randomized clinical trial found that, when using Invisalign clear aligners to treat minor malocclusions, treatment duration was longer than traditional braces by 4.8 months. [27] Most respondents in the present study (especially males) believed that Invisalign treatment produces superior results to traditional braces. ...
Objectives:
The demand for clear aligner treatment has increased in recent years. Thus, this study investigated public knowledge regarding Invisalign clear aligner treatment.
Material and Methods:
A web-based survey was administered through different social media platforms covering different aspects of Invisalign treatment, namely: Treatment efficiency, patient discomfort, appliance esthetic attractiveness, oral hygiene maintenance, and treatment aesthetic results. Participants were also asked to outline their perception of Invisalign treatment cost. A Likert-type scale was used to rank the participant responses. Data were analyzed with the Chi-square test and Bonferroni correction for multiple comparisons.
Results:
Out of 934 eligible adult participants, 19.6% were aware of Invisalign. Most of the Invisalign-familiar respondents were unaware of its cost (27.9%) but agree it is generally better (49.7%), requires fewer visits (38.2%), results in shorter treatment duration (39.4%) and reduced teeth discomfort (35%), more esthetically attractive (64%), yields easier oral hygiene maintenance (55.2%), and produces superior esthetic results (43.7%) than traditional braces. In addition, males and average-income participants were more likely to believe that Invisalign treatment produces superior esthetic results than traditional braces (P = 0.0002 and P = 0.002, respectively). Average-income participants also believed that Invisalign treatment was generally better (P < 0.0001). While participants in the age-range 55–64 years strongly believe, it is cheaper (P < 0.0001) than traditional braces.
Conclusion:
This study highlighted the lack of public knowledge about Invisalign treatment. The results also indicated the importance of ensuring public access to reliable information backed up by high-quality evidence.
... This tool contains 12 questions, with a global ideal score for comparative studies of 24 points. The quality assessment of the included studies was measured as follows: 0 to 6 points, very low quality; 7 to 12 points, low quality; 13 to 18 points, moderate quality; and 19 to 24 points, high quality (Pithon et al., 2019). ...
Background: The treatment of rheumatoid arthritis (RA), a chronic systemic inflammatory autoimmune disease, is based on disease-modifying anti-rheumatic drugs (DMARDs). Typically, it starts with conventional synthetic DMARDs (csDMARDs), and depending on the patient’s response to the treatment and the adverse events experienced, biological DMARDs (bDMARDs) are initiated. bDMARDs are more specific to inflammatory factors than csDMARDs and more efficient in inducing remission and low disease activity. Thus, this study aimed to assess the effectiveness of biological therapy in patients with rheumatoid arthritis in administrative health databases.
Methods: PubMed, Embase, Lilacs, Ovid, Scopus, and Web of Science databases were searched from inception to 21 October 2021, to identify observational studies that evaluated the effectiveness of biological therapy in patients with rheumatoid arthritis using administrative databases and real-world data. The methodological quality was assessed by the methodological index for non-randomized studies (MINORS). A fixed or random-effects model estimated risk ratios with 95% confidence intervals. The analysis was divided into four groups: tumor necrosis factor inhibitors (TNFi) versus non-TNFi; TNFi versus TNFi (adalimumab, etanercept, and golimumab versus infliximab); bDMARDs versus Janus kinase inhibitors (JAKi); and bDMARDs monotherapy versus combination therapy (bDMARDs and MTX).
Results: Twenty-one records were eligible for inclusion in this systematic review and meta-analysis; seven population-based cohorts, eight prospective, and six retrospective cohort studies. Overall, 182,098 rheumatoid arthritis patients were evaluated. In the meta-analysis, lower effectiveness was observed among TNFi users than in non-TNFi (RR: 0.88; 95% CI: 0.81–0.95; p < 0.01; I² = 94.0%) and bDMARDs than in JAKi (RR: 0.86; 95% CI: 0.79–0.94; p < 0.01; I² = 93.0%). Higher effectiveness among adalimumab, etanercept, and golimumab than in infliximab (RR: 1.19; 95% CI: 1.05–1.36; p < 0.01; I² = 96.0%) was found. No significant differences in the effectiveness of bDMARD monotherapy compared to combination therapy (RR: 0.83; 95% CI: 0.68–1.00; p < 0.01; I² = 81.0%) was observed. E-value analysis indicated that the estimates were not robust against unmeasured confounding.
Conclusion: According to the available real-world data, our results suggest that biological therapy effectively treats patients with rheumatoid arthritis, indicating higher effectiveness with non-TNFi and JAKi than with TNFi.
Systematic Review Registration: https://www.crd.york.ac.uk/prospero/display_record.php?ID#CRD42020190838, identifier CRD42020190838.
... The solution that does not interfere with the appearance of dental arches is the use of braces mounted on the lingual surfaces of teeth or the use of aligners, which are becoming more and more popular. Unfortunately, both of the above-mentioned methods have limitations that do not allow optimal results to be achieved in the treatment of severe malocclusion [2][3][4][5]. In addition, the use of lingual techniques significantly increases the costs of therapy and often extends the period of follow-up visits. ...
The high aesthetic value of orthodontic appliance elements during treatment constitutes an important factor for an increasing number of adult patients. The aim of this study was to determine whether food dyes could significantly affect the color of both plastic and ceramic orthodontic brackets. Four brands of orthodontic brackets were investigated in the present study. Twenty-five samples of each kind were prepared. Five brackets of each series were stored in pure water, coffee, black tea and red wine for 1 h, 24 h, 7 days and 14 days. Total color change ∆E* of the samples was analyzed after storage with the use of the SpectroShade dental spectrophotometer (MHT, Verona, Italy) according to the CIE L*a*b* color scale. Correlations between bracket brand, kind of food dye and intensity of color change at the significance level p = 0.05 were investigated. After 1 and 24 h of incubation, water had the least influence on the color change of aesthetic orthodontic brackets, and tea had the greatest effect (p = 0.05). After 7 and 14 days of incubation of the samples, water still remained the environment influencing ∆E* change to the smallest extent, whereas storage in red wine changed the color of brackets to the significantly (p = 0.05) highest degree. The degree of discoloration of the assessed brackets depended on the type of material and the storage time in the environment of the individual food dyes (p = 0.05). The results of the present study show that, in the event of contact with food dyes, aesthetic orthodontic brackets discolor, the intensity of which can be influenced by the materials they are made of, the kind of food dye and the time of samples' storage.
... In this regard, orthodontic treatment based on virtual setup would notably benefit from teleorthodontics since it is possible to eliminate simple visits while maintaining those relevant for the treatment strategies such as stripping, brackets/attachments or auxiliaries placement, and extraction [8,15,17]. is would enhance the treatment experience, making orthodontic treatment even more appealing for adults who are seeking invisible and efficient orthodontics [22,23], but also for clinicians since this would streamline the orthodontic workflow in the office [24]. ...
Teleorthodontics represents the orthodontic care system involving remote management of orthodontic treatment. Despite skepticism, there are several advantages of including teleorthodontics in the clinical orthodontic practice. In the present review, we discuss the lights and shadows of this new communication healthcare system and its applications in the field of orthodontics that is destined to change the future of our clinical practice. For this purpose, we have provided a point-to-point analysis based on data from the most valuable scientific evidence on this topic. e information and data discussed in the present paper were obtained from the most relevant studies evaluating the performance of teleorthodontics and remote monitoring systems in clinical practice.
Invisible or clear retainers have gained significant popularity as a post-orthodontic treatment option due to their clear, removable design and effectiveness in maintaining teeth alignment discreetly and comfortably. However, as with any dental intervention, adverse events may occur, particularly if the device is misused or if there is poor patient compliance. We present a case of extensive enamel and dentin destruction associated with the misuse of invisible retainers in a 14-year-old female patient who used the retainer for 30 months permanently, even eating with it. The extensive destruction needed several appointments until a complete reconstruction was obtained. Our clinical case underscores the importance of diligent post-treatment follow-up to guarantee the correct use of clear retainers. Communication and close follow-up are essential to guarantee the correct use of invisible retainers.
Background: This cephalometric study aimed to evaluate the effects of clear aligner therapy in growing individuals with Class II malocclusion, comparing two functional approaches: the use of Class II elastics or the Mandibular Advancement (MA). Methods: Cephalometric data from 39 patients with Class II malocclusion treated using clear aligners either combined with Class II elastics (EL group; n = 18) or Mandibular Advancement (MA group; n = 21) were analyzed and compared with an untreated control group (UC2; n = 15). Results: Both treatment groups (EL and MA) showed a significant reduction in the ANB angle compared to the control (MA: −1.5°; EL: −2.2°; UC2: +0.2°). An increase in mandibular length, as measured by Co–Gn, was observed in both the EL and MA groups (+5.5 mm and +8.3 mm, respectively) relative to the control group. Soft tissue analysis of the Pg–TVL distance from T1 to T2 revealed the most substantial forward displacement of the chin in the MA group (MA: +2.0 ± 3.7 mm; EL: +0.5 ± 0.7 mm; UC2: −1.6 ± 3.3 mm). Vertically, the MA group exhibited a more marked decrease in the palatal-mandibular plane angle than the other groups. Both treatment modalities significantly reduced overjet and overbite from T1 to T2. Conclusions: The EL and MA appliances effectively advanced the mandible, leading to significant improvements in the sagittal relationship, overjet, and overbite while maintaining stable vertical control. Additionally, the MA group exhibited a more pronounced forward movement of the soft tissue chin.
Introduction
Orthognathic surgery, a well-established procedure for correcting significant skeletal imbalances, addresses both aesthetic and functional concerns. Traditionally, fixed orthodontic appliances have been preferred due to their effectiveness in managing dental movements and ensuring postoperative stability. However, the increasing demand for more aesthetic and comfortable options has led to the growing use of clear aligners, even in complex surgical cases. Although aligners present some limitations, such as reduced control over certain dental movements and the need for greater patient compliance, they offer notable advantages in terms of comfort and aesthetics. Similar to fixed appliances, the successful integration of aligners with orthognathic surgery requires meticulous planning and close coordination between the orthodontist and surgeon.
Objective
This article provides detailed guidelines for professionals on planning and executing orthodontic-surgical treatments using clear aligners, covering both conventional and surgery-first approaches. Clinical examples will illustrate the aesthetic and functional benefits, as well as key technical challenges in daily practice.
Background: Clear aligners have become a pivotal advancement in orthodontic treatment, offering a viable alternative to traditional metal braces. Despite the reported benefits of clear aligners such as being more hygienic and aesthetic, some orthodontists remain sceptical about the effectiveness of aligners in achieving treatment goals. This uncertainty may arise due to traditional preferences or the perceived limitations in their ability to execute complex tooth movements. Aim of the study: This systematic review investigates the effectiveness of clear aligners in achieving dentoalveolar expansion of the maxillary arch. Materials and methods: An electronic search was conducted on PubMed, Web of Science, Google Scholar, and Scopus from January 2020 to July 2024 to identify relevant articles. Methodological shortcomings were highlighted, and an evaluation of the quality of the included studies was completed using the Risk of Bias in Non-randomised Studies of Interventions (ROBINS-I) tool. Results: Out of 453 studies identified, seven studies met the inclusion criteria and were included in this review. Four studies were on adult subjects with full permanent dentition and three were on subjects with mixed dentition. The risk of bias was generally minimal according to the ROBINS-I tool in all the studies reviewed. The efficacy of expansion with clear aligners was more prominent in the canine and premolar area, with the expansion mainly achieved with tipping movements rather than bodily translation movement. The planning software overpredicted the dental movements compared to what was achieved. Conclusions: Clear aligners primarily achieve expansion via dental tipping. Overcorrection and buccal root torque should be planned to ensure more bodily movements and expansion goals are met after treatment. Employing clear aligners in younger patients is particularly advantageous for upper arch development and correction of transverse malocclusions, especially in the canine segment.
Introduction
Although with increasing popularity due to aesthetic appeal and comfort, clear aligners (CAs) are facing challenges in efficacy and predictability. Advancement in the underlying biomechanical field is crucial to addressing these challenges. This paper endeavors to provide a comprehensive framework for understanding the biomechanics of CA and enlightening biomechanics-based improvements on treatment strategies.
Methods
A thorough review of the English-language literature accessible through PubMed and Google Scholar, without any publication year restrictions, was undertaken to unravel the biomechanical aspects of CA.
Results
This review presented an up-to-date understanding of aligner biomechanics arranged by the framework of the material-dependent mechanical characteristics of CA, the geometric characteristics-dependent force transmission of the CA system, methods for studying the biomechanics of CA, and the biomechanical analyses for different types of tooth movement.
Conclusions
Biomechanics should be the fundamental concern for concepts, methods and adjuncts attempting to enhance the accuracy and predictability of tooth movement induced by CA. Improvement on material properties and alteration of geometric design of CA are two main approaches to develop biomechanically optimized force system. Exploration of real-world force sensing and monitoring system would make substantial progresses in aligner biomechanics.
Background Current 3D printing materials limit the mechanical properties of directly 3D-printed clear dental aligners. This study aimed to evaluate the mechanical properties of direct 3D-printed clear resin embedded with orthodontic wire under different surface treatments to provide a new integration method for orthodontic appliances and treatment. Methods Samples were prepared with stainless-steel wire and direct 3D-printing clear resin. The different surface treatments were applied to the wires and divided into three groups: control (C), sandblasting (S), sandblasting and acid etching (SA), and then the surface characteristics were analyzed. Static and dynamic mechanical tests were performed to measure interfacial shear strength (IFSS), elastic modulus, tensile strength, and stress relaxation. Results The average roughness and surface morphology of stainless-steel wires exhibited significant differences (P < 0.001) when applying different surface treatments. Sandblasting and acid-etching significantly affected IFSS, improving the adhesion by a factor of 5 from 5.71 MPa to 28.84 MPa. The elastic modulus and tensile strength increased significantly in the 3D-printed resin embedded with the wire group compared to the 3D-printed pure resin group but did not change significantly between the different surface treatments of the wire. The sandblasting and acid-etching group produced higher residual stress than the other three groups in the 6 hours and cyclic stress relaxation. Conclusion This study presents the development of 3D-printed clear dental aligners with embedded metal wires for orthodontic treatment. Surface treatment of orthodontic metal wire through sandblasting and acid etching improves the bond between the wire and 3D printing clear resin, thereby improving the static and dynamic mechanical properties of directly 3D-printed clear resin appliances. The developed process and device can offer an integrated solution that enables advanced orthodontic treatments by providing stabilized orthodontic forces.
Introduction
Orthodontic improvements, mainly through the previous decade, have led to a substantial rise in patients’ esthetic needs. Traditional orthodontic procedures have been linked with a compromise in facial appearance, which increases concern among patients pursuing orthodontic treatment.
Methods
PubMed, MEDLINE, Google Scholar, and Cochrane Library of Systematic Reviews databases were searched using appropriate entry terms and Boolean operators. Search strategy was conducted till June 2022 for systematic reviews and meta-analyses. Publications were systematically assessed for eligibility, and two observers independently graded the methodologic quality using AMSTAR-2 tool. For each meta-analysis, we estimated the summary effect size by the use of random-effects and fixed-effects models and the 95% confidence interval. We estimated the between-study heterogeneity expressed by I ² (defined as large for I ² ≥50%), evidence of small-study effects (i.e., large studies had significantly more conservative results than smaller studies), and evidence of excess significance bias (i.e., more studies than expected with significant results).
Results
Overall, 16 unique systematic reviews and meta-analyses following the eligibility criteria were selected for umbrella review. The results of qualitative analysis of studies revealed that 4 studies had a critically low risk of bias, 11 showed low risk, and 1 study had moderate risk. The results of the meta-analysis favored clear aligners with respect to oral hygiene and root resorption parameters. When tooth movements were considered, the results favored conventional orthodontic treatment.
Conclusion
Clear aligner therapy (CAT) has significant advantages with regard to efficiency (treatment time, chair time) in mild-moderate malocclusion cases. The overall accuracy of CAT when compared to fixed orthodontic treatment was found to be 55-82%.
Background
To study and compare the effects of clear aligners without brackets and traditional fixed aligners in orthodontic treatment.
Methods
The samples were collected from January 2022 to April 2023. The control group (n = 26) received orthodontic treatment using traditional fixed appliances. The research group (n = 20) received orthodontic treatment using the clear aligners without brackets. Compare the therapeutic effects and related evaluation indicators between two groups.
Results
The total effective ratio was compared between the 2 groups, and the study group was greater(P < 0.05). After treatment, the detected values of the periodontal condition indicators (plaque index, debris index, and gingival bleeding index), serum inflammatory factors (CRP, IL-6 and TNF-α) of the two groups, were less than before, also were all less than the control group. (P < 0.05). After therapy, in comparison of the control group, the value of mastication efficiency, comfort and psychological evaluation, sleep indicators and the points of the four dimensions of life quality in the study group was greater, and the detection results were obviously greater than before(P < 0.05).
Conclusion
In the orthodontic therapy of sufferers with malocclusion, compared with the traditional fixed appliance, the clear aligners without brackets can enhance the treatment effects, improve the periodontal condition and masticatory function, and reduce the inflammatory responses, so that patients can feel more comfortable, thereby improving their psychology, sleep and quality of life. In the future, with the continual advancement of technology and people’s pursuit of beauty, the application of clear aligners without brackets in orthodontic treatment will become more and more extensive. The continuous introduction of new materials and new technologies will further improve the effects and comfort of the clear aligners without brackets, reduce treatment time and discomfort, and also reduce patients’ resistance to aligners, bringing patients a better treatment experience.
Background
Orthodontics is a common treatment for malocclusion and is essential for improving the oral health and aesthetics of patients. Currently, patients often rely on the clinical expertise and professional knowledge of doctors to select orthodontic programs. However, they lack their own objective and systematic evaluation methods to quantitatively compare different programs. Therefore, there is a need for a more comprehensive and quantitative approach to selecting orthodontic treatment plans, aiming to enhance their scientific validity and effectiveness.
Methods
In this study, a combination of the analytic hierarchy process (AHP) and semantic analysis was used to evaluate and compare different orthodontic treatment options. An AHP model and evaluation matrix were established through thorough research and semantic analysis of patient requirements. This model considered various treatment factors. Expert panels were invited to rate these factors using a 1–9 scale. The optimal solution was determined by ranking and comparing different orthodontic treatment plans using the geometric mean method to calculate the weights of each criterion.
Results
The research indicates a higher preference for invisible correction compared to other orthodontic solutions, with a weight score that is 0.3923 higher. Factors such as comfort and difficulty of cleaning have been given significant attention.
Conclusion
The Analytic Hierarchy Process (AHP) method can be utilized to effectively develop orthodontic treatment plans, making the treatment process more objective, scientific, and personalized. The design of this study offers strong decision support for orthodontic treatment, potentially improving orthodontic treatment outcomes in clinical practice and ultimately enhancing oral health and patients’ quality of life.
Background
With orthodontic patient demographics expanding to involve more adults, the demand for esthetic appliances is greater and orthodontists are keen on offering their patients more discreet and even invisible options. Clear aligners are a very viable option which offers all this, and it is noteworthy that more and more orthodontists in India are practicing the craft. Keeping this vision in mind, and the fact that aligners are revolutionary and here to stay, this study was conducted to assess the efficiency of various tooth movements carried out with clear aligner therapy as compared to traditional orthodontic treatment.
Aim
This questionnaire-based survey aimed to analyze and assess the orthodontists’ perception and experience of various tooth movements carried out with clear aligner in their routine clinical practice in India.
Methodology
A cross-sectional study was conducted by sending out a questionnaire on a virtual platform. It was approved by the Ethical Committee of the Dental Institute it was carried out in (Ref no: SDCH/IEC/OUT 2021/13). A sample size of 205 participants within the age group of 27–59 years was taken. The participants comprised of orthodontists practicing in various parts of India. A questionnaire, comprising of 22 closed-ended questions, was created on Google forms and circulated to participants using various social media platforms. The data of responses of participants were analyzed and evaluated with the help of chi-square test and p values were interpreted for the significance of responses.
Results
This survey analyzed the experience of orthodontists with respect to the various tooth movements carried out with clear aligners. There were mixed responses, but most of them suggested the aligners to be either same in effectiveness or poorer than the fixed appliances in carrying out various tooth movements.
Conclusion
This questionnaire-based survey helped in analyzing the orthodontists’ perception on the use of clear aligners in their routine clinical practice in India. It most importantly helped in assessing various kinds of tooth movements achievable with clear aligners. It also helped in getting an opinion on the movements presently not possible with aligners alone. This study clearly suggests that the general perception amongst the orthodontists is that more advancement is needed as far as aligners are concerned before they become competent enough to deal with various tooth movements easily achievable with fixed appliances.
Introduction:
In an ideal clinical setting, orthodontic therapy with clear aligners (CA) should improve the patients' initial malocclusion and must guarantee equivalence between the results predicted and those obtained clinically to be considered an effective treatment. Therefore, this scoping review aimed to identify the orthodontic literature concerning the effectiveness and predictability of CA treatments.
Methods:
A systematic computerized search was performed in 3 databases: PubMed, Scopus, and Embase. Inclusion criteria selected observational and clinical studies performed in at least 10 adult orthodontic patients, whose results of CA treatment's effectiveness and/or predictability were assessed.
Results:
The 3 database computerized searches resulted in 1,553 articles, and 169 full texts were considered potentially relevant. After applying the eligibility criteria, 33 studies were included. Most studies (76%) were designed as cohort studies and have been published in the last 5 years (79%). The majority included only non-extraction treatments (73%), and 79% reported results achieved with the Invisalign® system. The most predictable movement was the buccolingual tipping, while the least predictable movements were rotation, intrusion, and extrusion. Aligner treatment was effective for mild to moderate crowding resolution, and the success of overbite correction still seems to be limited.
Conclusions:
The studies have demonstrated improvement of initial malocclusion through CA treatments. Still, predictability degree is overestimated and does not accurately reflect the occlusion immediately at the end of treatment. In future studies, there should be an effort to broaden the utilization of alternative aligner systems beyond Invisalign® and broadly disseminate their outcomes to strengthen clear aligners evidence base.
Background
Over the last two decades, clear aligners have become a mainstay in contemporary orthodontic practice primarily due to improvements in digital and 3D printing technologies, a growing interest in esthetic orthodontics, especially in the adult population, and aggressive manufacturer marketing internationally.
Material and Methods
PubMed, Google Scholar, Cochrane Library, and EMBASE databases were searched from January 1998 to November 2021. The search terms used were “Invisalign” OR “clear aligner.” A total of 7000 records were searched, of which 369 potentially relevant articles were retrieved in full. 190 studies met the selection criteria following screening and were included in the scoping review.
Results
This review scopes and analyses published orthodontic literature about CA according to a year-wise distribution into 3 groups, 2001–2010/2011–2020/2021. Most of the studies were published in the period between 2011 and 2020, with 138 studies accounting for 73%. The year 2021 followed, with 31 studies accounting for 16%, which was greater than the number of studies published in 10 years from 2001 to 2010. Studies were also classified based on the study designs with most of the published studies representing the lowest level of evidence including case reports, case series, narrative reviews, expert opinions, and editorials accounting for 137 studies, whereas case-control studies were the least reported studies with only 4 studies reported in the literature. In addition, they were categorized into seven main domains: (1) Biological considerations associated with clear aligner therapy (CAT), (2) Treatment outcomes considerations associated with CAT, (3) Geometrical considerations associated with CAT (clinical), (4) Biomechanical considerations associated with CAT (Laboratory/Finite element analysis), (5) Biomaterial considerations associated with CAT, (6) Patient education and experience and aesthetic and social perception of CAT, and (7) Miscellaneous. Treatment outcome considerations associated with CAT had the greatest percentage representing 36% of the total published domains, while the final place was occupied by the biomechanical considerations associated with CAT accounting for only 4% of the published domains about CAT.
Conclusion
Treatment outcome was the domain most commonly reported by studies accounting for (36%). Most of the published studies are at the lowest level of evidence including case reports, case series, narrative reviews, and expert opinions. The vast majority of studies utilized only a single clear aligner brand. There is a greater need for research that studies CAT from a holistic perspective.
Objectives
The objective of this study was to assess bone biomarkers and cytokines in patients with conventional labial appliances (CLAs) and aligners.
Materials and Methods
Participants were recruited to undergo orthodontic treatment with CLAs and aligners according to predefined inclusion and exclusion criteria. Periodontal examination was accomplished at baseline and 4 weeks using the plaque index (PI), gingival index (GI), and bleeding on probing (BoP). Samples of gingival crevicular fluid (GCF) were collected at baseline (T0) before the start of treatment and at the 1-month follow-up (T1) to assess bone metabolic and inflammatory biomarkers. GCF from participants with CLAs and aligners was evaluated with enzyme-linked immunosorbent assay. Comparison between labial conventional orthodontic treatment and aligners were assessed using an unpaired t-test. The difference between T0 and T1 was measured using a paired t-test.
Results
BoP, PI, and GI demonstrated no significant difference between participants treated with aligners and subjects with CLAs at baseline and at 4 weeks (P > .05). Bone markers and other biomarkers (tumor necrosis factor α, interleukin [IL]-α, IL-2, IL-6, and IL-8) showed significant differences (P < .05). Also, a significant difference between CLAs and aligners was noted among all biomarkers (P < .05) except IL-β.
Conclusions
Aligners and CLAs increase the level of inflammatory and bone metabolic biomarkers after 1 month.
The clear aligner treatment in the last years has been increasing its relevance and use. The use of aligners to treat malocclusion has had a remarkable surge in the last decades, a growing interest has been reported for such methods of invisible orthodontics, especially among adult patients. Clear aligners are orthodontic devices that use elastic thermoplastic material, applying pressure to the teeth to move into the aligner’s position, being an alternative to dental braces. They are esthetic, efficient, and comfortable compared to a traditional fixed appliance for mild-to-moderate malocclusion. A clinician should know strengths and weaknesses of aligners for a correct use, being guided by clinical indications. The present paper will highlight the increasing popularity of clear aligner appliances, as well as the clinical scope and the limitations of aligner therapy in general.
Background: In the last decades, adult patients require orthodontic treatment as a therapeutic method in an increasing percentage. This treatment has a lot of benefits, but unfortunately it also presents a number of complications and risks, among which favoring the accumulation of bacterial plaque is the most concerning.
Aim of the study: In this study we aimed to evaluate the effectiveness of using the dark-field microscope as a method of motivating adult patients with orthodontic treatment in maintaining a proper oral hygiene.
Material and methods: Thirty-six patients were selected based on the inclusion and exclusion criteria. At time T0, patients were divided into two groups: Group 1–microscope and Group 2 – control, in such a way that the groups were as homogeneous as possible. Dental plaque samples were collected and analyzed under a dark field microscope in the presence of the patient for subjects from Group 1 but not Group 2. All patients were then instructed on oral hygiene techniques. The following periodontal indices were recorded of each patient: plaque index (PI), index of bleeding on probing (BOP), probing depth (PD) – at T0 and T1 (after one month).
Results: Comparing the PI and BOP values before (T0) and after treatment (T1), statistically significant results were detected (PI: p = 0.0020, BOP: p = 0.0297), which denotes that patients who observed the bacterial load of their dental plaque in real time using the dark-field microscope had a better oral hygiene and lower values of periodontal health indices. Regarding the PD index, the difference between time T0 and T1 was not statistically significant (p = 1.4762).
Conclusions: During the orthodontic treatment, adult patients often present gingival inflammation caused by improper hygiene. The use of the dark-field microscope is effective in motivating patients regarding the rules of maintenance of a proper oral hygiene.
Hovedbudskap
For å gi pasientene våre best mulige resultater og opplevelse av behandling må behandlere som bruker alignere kjenne til fordeler og begrensninger i bruken av behandlingsmetoden.
Generell kjeveortopedisk viten, forståelse av okklusjon, respekt for de biologiske grenser hos den enkelte pasient og oppstilling av behandlingsmål må være på plass før start av behandling med alignere.
Utvelgelsen av pasienter er ytterst viktig for å respektere læringskurven og bli fortrolig med teknikken.
Simuleringer av behandlingsresultater før oppstart har flere problemer med presisjon av flere bevegelsestyper, hvilket må korrigeres for før behandlingsstart i de mer kompliserte pasienttilfellene.
Baykov A.V., Shaghbatyan T.L. Bedside teaching in undergraduate medical education. Medicine, Science and Education, N 33, 2022, Yerevan, 35-41; https://doi.org/10.56936/18291775-2022.33-35.
Baykov AV, Shaghbatyan TL (2022). Bedside teaching in undergraduate medical education. Medicine, Science and Education. Yerevan. 33: 35-41
Keywords: bedside teaching, clinical teaching, higher medical education, clinical skills.
Baykov A.V., Shaghbatyan T.L. Bedside teaching in undergraduate medical education. Medicine, Science and Education, N 33, 2022, Yerevan, 35-41; https://doi.org/10.56936/18291775-2022.33-35.
Keywords: bedside teaching, clinical teaching, higher medical education, clinical skills.
Introduction
A high number of women are exposed to acetaminophen during pregnancy worldwide. This drug safety during pregnancy regarding preterm birth, birth weight, and fetal development has not been well described. This study investigated the effect of acetaminophen use during pregnancy on selected adverse pregnancy outcomes.
Areas covered
Databases were searched to identify studies reporting the effects of acetaminophen use during pregnancy on preterm birth, low birth weight, and small for gestational age. The studies’ quality was assessed by the Newcastle-Ottawa Scale and the Methodological Index for Non-Randomized Studies. Relative risk with 95% confidence intervals of each outcome was estimated using a fixed or random‐effects model. Six studies were included for final review, four cohort and two case‐control studies. We found no increased risk of preterm birth (RR 0.97; 95% CI 0.59-1.58), and decreased risks of low birth weight (RR 0.65; 95% CI 0.59-0.72) and small for gestational age (RR 0.69; 95% CI 0.50-0.97). Acetaminophen exposure during the third trimester revealed non-significantly in the outcomes.
Expert opinion
Exposure to acetaminophen during pregnancy appears to not increase the risk of the outcomes analyzed. However, there is a lack of information regarding the exposure dose and frequency of acetaminophen use.
Background
Clear aligners (CAs) can distalize mandibular molars. The present study aimed to study the efficiency and influencing the factors of CAs for mandibular molar distalization and to provide guidance for clinical design.
Materials and Methods
The present study evaluated 32 adult orthodontic patients who needed mandibular molar distalization and were treated with CAs between September 2018 and September 2020 at the school of medicine. The cone-beam computed tomography images of T 0 (before orthodontic treatment) and T 1 (after mandibular molars were fully distalized) were collected, and the actual movements of mandibular molars were measured and compared with the expected movements. The efficiency of mandibular molar distalization during treatment was comprehensively evaluated, and the relevant factors were analyzed.
Results
For mandibular first molar distalization, the average efficiency of the crown was 67.19% 9swn. 13%, and that of the root was 37.87% 7stn. 72%. There was a significant difference between the achieved movement amount and the expected amount ( P < 0.05). For mandibular second molars, the average efficiency of the crown was 58.47% 7swn. 07%, and that of the root was 57.03% 3stn. 48%. There was a statistically significant difference between the achieved movement amount and the expected amount ( P < 0.05). There was a significant negative correlation between the expected movement and the efficiency of the crown.
Conclusions
CAs can achieve mandibular molar distalization, and the movement pattern of molars is mainly a tipping movement. To accomplish bodily movement, overcorrection should be fully considered. In addition, it is suggested that close attention should be given to observing root movement during molar distalization.
This treatment-outcome assessment objectively compares Invisalign (Align Technology, Santa Clara, Calif) treatment with braces.
This study, a retrospective cohort analysis, was conducted in New York, NY, in 2004. Records from 2 groups of 48 patients (Invisalign and braces groups) were evaluated by using methods from the American Board of Orthodontics Phase III examination. The discrepancy index was used to analyze pretreatment records to control for initial severity of malocclusion. The objective grading system (OGS) was used to systematically grade posttreatment records. Statistical analyses evaluated treatment outcome, duration, and strengths and weaknesses of Invisalign compared with braces.
The Invisalign group lost 13 OGS points more than the braces group on average, and the OGS passing rate for Invisalign was 27% lower than that for braces. Invisalign scores were consistently lower than braces scores for buccolingual inclination, occlusal contacts, occlusal relationships, and overjet. Invisalign's OGS scores were negatively correlated to initial overjet, occlusion, and buccal posterior crossibite. Invisalign patients finished 4 months sooner than those with fixed appliances on average. P < .05 was used to determine statistically significant differences.
According to the OGS, Invisalign did not treat malocclusions as well as braces in this sample. Invisalign was especially deficient in its ability to correct large anteroposterior discrepancies and occlusal contacts. The strengths of Invisalign were its ability to close spaces and correct anterior rotations and marginal ridge heights. This study might help clinicians to determine which patients are best suited for Invisalign treatment.
The aim of this study was to assess treatment outcomes of the Invisalign and compare results with braces.
One hundred and fifty-two adult orthodontic patients, referred to two Orthodontic Specialist Clinics, were randomized to receive either invisalign or brace treatment. All patients were evaluated by using methods from the American Board of Orthodontics Phase III examination. The discrepancy index was used to analyze pretreatment records to control for initial severity of malocclusion. The objective grading system was used to systematically grade posttreatment records. The Wilcoxon 2-sample tests were used to evaluate treatment outcome of Invisalign and braces.
The total mean scores of the objective grading system categories were improved after treatment in both groups. The improvements were not statistically significant in scores for alignment, marginal ridges, occlusal relations, over jet, inter-proximal contacts, and root angulation. Invisalign scores were consistently lower than braces scores for buccolingual inclination and occlusal contacts.
The overall improvement in OGS scores indicate that both Invisalign and fixed appliances were successful in treating Class I adult extraction cases in this sample.
Gynura bicolor (Roxb. & Willd.) DC., a perennial plant belonging to the Asteraceae family, is originated from the tropical area of Asia. The total hemocyte count (THC), phenoloxidase (PO) activity, respiratory bursts (RBs), superoxide dismutase (SOD) activity, and lysozyme activity were examined after white shrimp Litopenaeus vannamei had been fed diets containing the water extract of G. bicolor at 0 (control), 0.5, 1.0, and 2.0 g (kg diet)(-1) for 7-28 days. The results indicated that these parameters increased accordingly with the amount of extract and time. THCs of the shrimp fed the G. bicolor diets at 1.0 and 2.0 g (kg diet)(-1) were significantly higher than that fed the control diet for 14-28 days. For the shrimp fed the G. bicolor diets at 0.5, 1.0, and 2.0 g (kg diet)(-1), the PO, RBs, and lysozyme activities reached the highest levels after 7 days, whereas SOD activity reached the highest levels after 14 days. In a separate experiment, white shrimp L. vannamei fed the diets containing the G. bicolor extract for 28 days were challenged with Vibrio alginolyticus at 3 x 10(6) cfu shrimp(-1) and white spot syndrome virus (WSSV) at 1 x 10(3) copies shrimp(-1). The survival rate of the shrimp fed the G. bicolor diets was significantly higher than that of the shrimp fed the control diet at 48-144 h post challenge V. alginolyticus and WSSV. For the shrimp fed the G. bicolor diets at 0.5, 1 and 2 g (kg diet)(-1) under challenges of V. alginolyticus and WSSV, their LPS- and beta-1,3-glucan-binding protein (LGBP) and peroxinectin (PE) mRNA expressions were significantly higher than those of the challenged control shrimp at 12-96 and 24-144 h post-challenge, respectively. We concluded that dietary administration of a G. bicolor extract could enhance the innate immunity within 28 days as evidenced by the increases in immune parameters (PO, RBs, and lysozyme) and antioxidant enzyme (SOD) activities of shrimp to against V alginolyticus and WSSV infections.
In this study, we examined the impacts of age, sex, root length, bone levels, and bone quality on orthodontic tooth movement.
Clear aligners were programmed to move 1 central incisor 1 mm over the course of 8 weeks. Thirty subjects, ages 19 to 64, were enrolled, and measurements were made on digital models (percentage of tooth movement goal achieved). Morphometric features and bone quality were assessed with cone-beam computed tomography. Data from this study were combined with data from 2 similar studies to increase the power for some analyses.
The mean percentage of tooth movement goal achieved was 57% overall. Linear regression modeling indicated a cubic relationship between age and tooth movement, with a decreasing rate of movement from ages 18 to 35 years, a slightly increasing rate from ages 35 to 50, and a decreasing rate from ages 50 to 70. The final decreasing trend was not apparent for women. As would be expected, the correlation was significant between the percentage of the goal achieved and the cone-beam computed tomography superimposed linear measures of tooth movement. A significant negative correlation was found between tooth movement and the measurement apex to the center of rotation, but bone quality, as measured by fractal dimension, was not correlated with movement.
The relationship between age and tooth movement is complex and might differ for male and female patients. Limited correlations with cone-beam computed tomography morphology and rate of tooth movement were detected.
Introduction
In this study, we examined the impacts of age, sex, root length, bone levels, and bone quality on orthodontic tooth movement.
Methods
Clear aligners were programmed to move 1 central incisor 1 mm over the course of 8 weeks. Thirty subjects, ages 19 to 64, were enrolled, and measurements were made on digital models (percentage of tooth movement goal achieved). Morphometric features and bone quality were assessed with cone-beam computed tomography. Data from this study were combined with data from 2 similar studies to increase the power for some analyses.
Results
The mean percentage of tooth movement goal achieved was 57% overall. Linear regression modeling indicated a cubic relationship between age and tooth movement, with a decreasing rate of movement from ages 18 to 35 years, a slightly increasing rate from ages 35 to 50, and a decreasing rate from ages 50 to 70. The final decreasing trend was not apparent for women. As would be expected, the correlation was significant between the percentage of the goal achieved and the cone-beam computed tomography superimposed linear measures of tooth movement. A significant negative correlation was found between tooth movement and the measurement apex to the center of rotation, but bone quality, as measured by fractal dimension, was not correlated with movement.
Conclusions
The relationship between age and tooth movement is complex and might differ for male and female patients. Limited correlations with cone-beam computed tomography morphology and rate of tooth movement were detected.
It is not necessary or desirable to treat every case of malocclusion that is presented. Many, if not most, of these children of 3 to 6 years can be safely put under observation in order that the tendency of growth can be noted. A fair percentage will be seen to improve as Nature seeks to correct some earlier period of retarded growth. Others may require the correction of a habit which is obstructing the normal course of development. Still others, such as the cases shown here, require slight mechanical corrections before normal function can be established and the forces of normal occlusion can exert their influence. Practically all of these cases suffer from low and improperly balanced muscle tone, and myofunctional therapy is used both during treatment and afterward to overcome this deficiency. As the span of attention is short in these younger cases, appointments must be kept brief and appliances simple; however, if these conditions are observed, the preschool children will be found to be among our most cooperative patients.
The aim of this study was to evaluate the changes in the transverse dimension and the perimeter of the maxillary arch produced by low friction self-ligating brackets TIME 3 compared to the Invisalign technique.
Both the self-ligating sample and the Invisalign group were composed of 20 subjects, evaluated at the beginning (T0) and at the completion of therapy (T1). All subjects presented a Class I malocclusion with mild crowding in a permanent dentition, without craniofacial anomalies, missing teeth or a history of orthodontic treatment. Dento-alveolar measurements were made on the maxillary dental casts at T0 and T1. Significant differences between the treated groups were assessed with Independent Samples t test (p<0.05).
Statistically significant differences between self-ligating sample and Invisalign group were recorded for CWC, FPWF, FPWL, SPWF, SPWL, and AP measurements. No significant changes were found for CWL, MWF, MWL, and AD values. There was not a statistically significant difference between the treatment durations of the groups: 1.8 years for both patients. These data suggest that Invisalign treatment cannot be somewhat faster than fixed appliances. Moreover the final occlusion might not be as ideal.
The low fiction self-ligating system produced statistically significant different outcomes in the transverse dento-alveolar width and the perimeter of the maxillary arch during treatment when compared to Invisalign tecnique.
This prospective study examined the adult patient's perception of recovery after insertion of three types of orthodontic appliances: Buccal, Lingual and Invisalign.
The sample consisted of sixty-eight adult patients (45 females and 23 males) who comprised three groups: 28 Buccal, 19 Lingual, and 21 Invisalign patients. After appliance insertion, patients completed a Health-Related Quality of Life questionnaire daily for the first week and again on day 14, in order to assess patients’ perception of pain and analgesic consumption. In addition, four areas of dysfunction were assessed: oral dysfunction, eating disturbances, general activity parameters, and oral symptoms.
Lingual appliance was associated with more severe pain and analgesic consumption, the greatest oral and general dysfunction, and the most difficult and longest recovery. The Invisalign patients complained of relatively high levels of pain in the first days after insertion; however this group was characterized by the lowest level of oral symptoms and by a similar level of general activity disturbances and oral dysfunction compared to the Buccal appliance.
Many Lingual and some Buccal patients did not reach a full recovery from their eating difficulties by the end of the study period.
The present study provides information to adult patients and clinicians assisting them in choosing the most appropriate treatment modality in relation to Health-Related Quality of Life parameters.
This study examined how halitosis, oral dryness and general oral health were impacted during treatment with the Invisalign(®) system. Furthermore, the effect of a lowdose chlorhexidine solution (CHX) was evaluated.
Thirtyone patients with good periodontal health participated in this crossover study and were divided into two groups (group 1: CHX/no CHX, group 2: no CHX/CHX). The following parameters were recorded during the first 8 months of Invisalign(®) treatment: stimulated saliva flow rate, organoleptic index, tongue coating index, measurement of the oral volatile sulfur compound level (ppb), modified gingival and plaque index and bleeding on probing index. Professional oral cleaning was performed at the beginning of each period lasting 3 months. The patients received a questionnaire at the first, third, fourth, sixth and eighth control visits.
The very low volatile sulfur compound level was significantly decreased by CHX (0.06%) during the first examination period (p = 0.02), i.e. for the first group of patients only. Neither halitosis, nor oral dryness, nor high plaque or gingival index measurements were observed. Oral health-related quality of life was hardly influenced by wearing aligners and oral hygiene habits were very good.
This study provides evidence that Invisalign(®) treatment is characterized by only minimal impairment of overall oral health and the associated quality of life. Consequently, it appears unnecessary to recommend the general adjunctive use of a low-dose chlorhexidine mouthwash during treatment with Invisalign(®).
The purpose of this prospective clinical study was to evaluate the efficacy of tooth movement with removable polyurethane aligners (Invisalign, Align Technology, Santa Clara, Calif).
The study sample included 37 patients treated with Anterior Invisalign. Four hundred one anterior teeth (198 maxillary and 203 mandibular) were measured on the virtual Treat models. The virtual model of the predicted tooth position was superimposed over the virtual model of the achieved tooth position, created from the posttreatment impression, and the 2 models were superimposed over their stationary posterior teeth by using ToothMeasure, Invisalign's proprietary superimposition software. The amount of tooth movement predicted was compared with the amount achieved after treatment. The types of movements studied were expansion, constriction, intrusion, extrusion, mesiodistal tip, labiolingual tip, and rotation.
The mean accuracy of tooth movement with Invisalign was 41%. The most accurate movement was lingual constriction (47.1%), and the least accurate movement was extrusion (29.6%)- specifically, extrusion of the maxillary (18.3%) and mandibular (24.5%) central incisors, followed by mesiodistal tipping of the mandibular canines (26.9%). The accuracy of canine rotation was significantly lower than that of all other teeth, with the exception of the maxillary lateral incisors. At rotational movements greater than 15 degrees, the accuracy of rotation for the maxillary canines fell significantly. Lingual crown tip was significantly more accurate than labial crown tip, particularly for the maxillary incisors. There was no statistical difference in accuracy between maxillary and mandibular teeth of the same tooth type for any movements studied.
We still have much to learn regarding the biomechanics and efficacy of the Invisalign system. A better understanding of Invisalign's ability to move teeth might help the clinician select suitable patients for treatment, guide the proper sequencing of movement, and reduce the need for case refinement.
In this report, three patients were treated with a new treatment protocol for Invisalign to demonstrate that a variety of complex malocclusions can be successfully treated using this protocol, including correction of moderate crowding, correction of moderate Class II division 1, and deep overbite. Previous studies of Invisalign showed significant limitations for more complex orthodontic treatment, although a few recent case reports have shown successfully completed moderate to difficult orthodontic malocclusions. One reason for the discrepancy is that the earlier studies were done during the first four years of the appliance development (now ten years of clinical use), when significant problems existed with accomplishing bodily movement, torquing of roots, extrusions, and rotations of premolars and canines. The new protocol included new methods for anterior/posterior corrections, showing on the computer the effect of elastics for Class II treatment simulated as a one-stage anterior/posterior movement at the end of treatment. Staging for interproximal reduction (IPR) is now automatically staged when there is better access to interproximal contacts to avoid IPR where significant overlap between teeth is present to avoid performing IPR on surfaces that may be damaged by instruments such as burs, strips, and disks when cut on a sharp angle. Staging for tooth movements is now also done to enable combination movements to occur simultaneously for each tooth with the tooth that needs to move the most (the lead tooth) determining the minimum number of stages required. All other teeth move at a slower rate than the lead tooth throughout the duration of treatment. Attachments are now placed in the middle of the crown automatically for rotation and automatically sized in proportion to the clinical crown. Use of 1 mm thick (buccal-lingual dimension) horizontal beveled rectangular attachments is standard on premolars for retention of aligners during intrusive movements, such as leveling the lower curve of Spee in deep overbite for extrusions and for control of the tooth long axis during torquing movements. Staging of tooth movements now track linear and rotational velocities of teeth separately with the number of treatment stages determined by the lead tooth based on its rotational or linear maximum velocities at no more than two degrees of rotation per stage. Simultaneous movements are done for all teeth providing visible space (approximately 0.05 mm) between teeth during movements past other teeth using expansion instead of IPR as a primary way to increase space available for correction of crowding.
The Invisalign System of tooth movement has been available to orthodontists since 1999 and has now become available to the entire dental profession. This paper explores the role of this system within the dental armamentarium and describes the clinical evolution of the appliance, based on a feasibility study initiated at the University of the Pacific in 1997.
Because of specific methodological difficulties in conducting randomized trials, surgical research remains dependent predominantly on observational or non-randomized studies. Few validated instruments are available to determine the methodological quality of such studies either from the reader's perspective or for the purpose of meta-analysis. The aim of the present study was to develop and validate such an instrument.
After an initial conceptualization phase of a methodological index for non-randomized studies (MINORS), a list of 12 potential items was sent to 100 experts from different surgical specialties for evaluation and was also assessed by 10 clinical methodologists. Subsequent testing involved the assessment of inter-reviewer agreement, test-retest reliability at 2 months, internal consistency reliability and external validity.
The final version of MINORS contained 12 items, the first eight being specifically for non-comparative studies. Reliability was established on the basis of good inter-reviewer agreement, high test-retest reliability by the kappa-coefficient and good internal consistency by a high Cronbach's alpha-coefficient. External validity was established in terms of the ability of MINORS to identify excellent trials.
MINORS is a valid instrument designed to assess the methodological quality of non-randomized surgical studies, whether comparative or non-comparative. The next step will be to determine its external validity when used in a large number of studies and to compare it with other existing instruments.
The aim of this study was to evaluate the differences in quality of life impacts between subjects treated with Invisalign aligners (Align Technology, Santa Clara, Calif) and those with fixed appliances during the first week of orthodontic treatment.
A prospective, longitudinal cohort study involving 60 adult orthodontic patients (33 with Invisalign aligners, 27 with fixed appliances) was completed by using a daily diary to measure treatment impacts including functional, psychosocial, and pain-related outcomes. A baseline survey was completed before the start of treatment; diary entries were made for 7 consecutive days to measure various impacts of the subjects' orthodontic treatment over time. The data were then analyzed for differences between treatment modalities in terms of the subjects' reported impacts from their orthodontic treatment.
The baseline mean values did not differ between groups for pain reports (P = .22) or overall quality of life impact (P = .51). During the first week of treatment, the subjects in the Invisalign group reported fewer negative impacts on overall quality of life (P <.0001). The Invisalign group also recorded less impact in each quality of life subscale evaluated (functional, psychosocial, and pain-related, all P <.003). The visual analog scale pain reports showed that subjects in the Invisalign group experienced less pain during the first week of treatment (P <.0001). The subjects in the fixed appliance group took more pain medications than those in the Invisalign group at days 2 and 3 (both P <.007).
Adults treated with Invisalign aligners experienced less pain and fewer negative impacts on their lives during the first week of orthodontic treatment than did those treated with fixed appliances.
Adult patients seeking orthodontic treatment are increasingly motivated by esthetic considerations. The majority of these patients reject wearing labial fixed appliances and are looking instead to more esthetic treatment options, including lingual orthodontics and Invisalign appliances. Since Align Technology introduced the Invisalign appliance in 1999 in an extensive public campaign, the appliance has gained tremendous attention from adult patients and dental professionals. The transparency of the Invisalign appliance enhances its esthetic appeal for those adult patients who are averse to wearing conventional labial fixed orthodontic appliances. Although guidelines about the types of malocclusions that this technique can treat exist, few clinical studies have assessed the effectiveness of the appliance. A few recent studies have outlined some of the limitations associated with this technique that clinicians should recognize early before choosing treatment options.
To compare the postretention dental changes between patients treated with Invisalign and those treated with conventional fixed appliances.
This is a comparative cohort study using patient records of one orthodontist in New York City. Two groups of patients were identified that differed only in the method of treatment (Invisalign and Braces group). Dental casts and panoramic radiographs were collected and analyzed using the objective grading system (OGS) of the American Board of Orthodontics (ABO). The cases were evaluated immediately after appliance removal (T1) and at a postretention time (T2), three years after appliance removal. All patients had completed active orthodontic treatment and had undergone at least one year of retention. A Wilcoxon rank sum test was used to evaluate differences in treatment outcomes between the groups for each of the eight categories in the OGS, including four additional subcategories in the alignment category. A Wilcoxon signed rank test was used to determine the significance of changes within each group from T1 to T2.
The change in the total alignment score in the Invisalign group was significantly larger than that for the Braces group. There were significant changes in total alignment and mandibular anterior alignment in both groups. There were significant changes in maxillary anterior alignment in the Invisalign group only.
In this sample for this period of observation, patients treated with Invisalign relapsed more than those treated with conventional fixed appliances.
To evaluate the influence of attachments and interproximal reduction on canines undergoing rotational movement with Invisalign.
In this prospective clinical study, 53 canines (33 maxillary and 20 mandibular) were measured from the virtual TREAT models of 31 participants treated with anterior Invisalign. The pretreatment virtual model of the predicted final tooth position was superimposed on the posttreatment virtual model using ToothMeasure, Invisalign's proprietary measurement software. A one-way analysis of variance (ANOVA) (P < .05) compared three treatment modalities: attachments only (AO), interproximal reduction only (IO), and neither attachments nor interproximal reduction (N). Student's t-tests (P < .05) compared the mean accuracy of canine rotation between arches.
The mean accuracy of canine rotation with Invisalign was 35.8% (SD = 26.3). Statistical analyses indicated that there was no significant difference in accuracy between groups AO, IO, and N (P = .343). There was no statistically significant difference (P = .888) in rotational accuracy for maxillary and mandibular canines for any of the treatment groups. The most commonly prescribed attachment shape was the vertical-ellipsoid (70.5%).
Vertical-ellipsoid attachments and interproximal reduction do not significantly improve the accuracy of canine rotation with the Invisalign system.
Cochrane Handbook for systematic reviews of interventions. Version 5.1.0 [updated
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Orthodontics and dentofacial orthopedics
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McNamara JA, Brudon WL, Kokich VG, eds. Orthodontics and dentofacial orthopedics. Ann Arbour, MI: Needham Press; 2001.
Cochrane Handbook for systematic reviews of interventions. Version 5.1.0 [updated
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Higgins JPT, Green S.Cochrane Handbook for systematic reviews
of interventions. Version 5.1.0 [updated March 2011]2011 August
2016. Available from http://handb ook.cochr ane.org/
The Invisalign Reference Guide
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Inc. AT. The Invisalign Reference Guide. Santa Clara, CA: Invisalign;2002.