Attachments for the Orthodontic Aligner Treatment—State of the Art—A Comprehensive Systematic Review
Abstract
:1. Introduction
2. Materials and Methods
2.1. Search Strategy
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- For MedLine (PubMed) and PubMedCentral: (“orthodontics”[MeSH terms] OR “malocclusion”[MeSH Terms] OR “Tooth movement techniques”[Mesh Major Topic]) AND (“aligner*”[All fields] OR “thermoformed splints”[All fields] OR “invisible splint*”[All fields]) AND (“attachment*”[All fields] OR “accessor*”[All fields] OR “auxill*”[All fields] AND “position*”[All fields]);
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- For Scopus: TITLE-ABS-KEY (((orthodontic*) OR (malocclusion)) AND (aligner*) AND ((attachment*) OR (accessor*) OR (auxill*) AND position*);
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- For Web of Science (“orthodontics” OR “malocclusion”) AND (“aligner*”OR “thermoformed splints” OR “invisible splint*”) AND (“attachment*” OR “accessor*” OR “auxill*” AND “position*”) (All Fields) and Article (Document Types);
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- For Embase: (“orthodontics” OR “malocclusion”) AND (“aligner*”OR “thermoformed splints” OR “invisible splint*”) AND (“attachment*” OR “accessor*” OR “auxill*” AND “position*”);
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- For EBSCO Dental and Oral Sciences: (“orthodontics” OR “malocclusion”) AND (“aligner*”OR “thermoformed splints” OR “invisible splint*”) AND (“attachment*” OR “accessor*” OR “auxill*” AND “position*”).
2.2. Eligibility Criteria
2.3. Data Extraction
2.4. Quality Assessment
Authors and Year | Type of Study | Studied Features | Subjects within the Study | Results and Clinically Relevant Conclusions |
---|---|---|---|---|
Alsaud et al. 2022 [16] | In vitro experimental study | The bonding strength of attachments to ceramic restorations | In total, 180 IPS e.max CAD specimens were divided into 12 different groups (n = 15 each). For surface roughness preparation, either 9.6% HF acid or 37% H3PO4 acid or air abrasion was used. For bonding, either Assure Bond or Single Bond Universal was used. The attachments were made either of condensable Filtek Z350 or of Z350 XT flowable composite. | The highest shear bond strength of composite attachments to ceramic restorations was achieved by using HF acid or air abrasion with Assure Bond and Filtek Z350 condensable composite. |
Bruno et al. 2021 [17] | Randomized control clinical trial | The influence of template type on bonding efficiency and attachment survival rate |
| The Spark group showed, in general, a lower frequency of debonding in comparison with the Invisalign group (87,5% vs. 73,5% of success rate after first bonding). Multiple failures occurred more often in the Invisalign group. However, no template characteristics proved to be crucial to this phenomenon. |
Chen et al. 2021 [18] | In vitro experimental study | The influence of composite material type on bonding efficiency |
| The operation time of Z350XT Flowable and SonicFill was shorter than Z350XT. The shear bond strength was the highest for SonicFill. SEM showed that the bonding interface of Z350XT and SonicFill was compact. The 3D deviation and volumetric change in the 3D designed attachments and the attachments after actual bonding of Z350XT Flowable were greater than that of Z350XT and SonicFill. The wear volume loss of SonicFill and Z350XT was less than that of Z350XT Flowable. |
D’Antò et al. 2019 [19] | In vitro experimental study | The influence of composite material type on bonding efficiency |
| Studied composites of different viscosities and did not present any difference in the shape and volume of attachments reproduced with a template on extracted teeth. The orthodontic composite showed more overflow when compared to the flowable one. |
Valeri et al. 2022 [20] | In vitro experimental study | The influence of transfer tray design and composite viscosity on the accuracy of attachment bonding |
| Transbond™ XT Light Cure Past attachments made with a rigid thicker transfer tray are associated with higher accuracy and minor dispersion. |
3. Results
3.1. Study Selection
3.2. Study Characteristics
- In vitro studies
- (a)
- Finite element analysis;
- (b)
- In vitro experimental studies.
- In vivo studies
- (a)
- Cross-sectional studies;
- (b)
- Randomized clinical trials.
3.3. Risk of Bias Assessment
4. Discussion
4.1. Attachment Bonding
4.2. Tooth Movement
4.3. Limitations and Direction of the Future Treatment
5. Conclusions
Author Contributions
Funding
Data Availability Statement
Conflicts of Interest
References
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Authors and Year | Type of the Study | Studied Phenomena | Subjects within the Study | Results and Clinically Relevant Conclusions |
---|---|---|---|---|
Ahmed et al. 2022 [21] | Finite element analysis | The influence of attachment positioning on movement efficiency (incisors intrusion/retrusion) and stress distribution |
| The most effective retraction was obtained by using palatal attachments. In the labial attachment model, the stress was concentrated in the middle third, while in all other models, this occurred in the cervical third. The model without an attachment generated the highest stresses. Placing the attachments on the labial surface can help avoid uncontrolled tipping. |
Ayidağa et al. 2021 [22] | Finite element analysis | The influence of attachment shape on movement efficiency (molar distalization) |
| All of the models were used to determine the effect on the periodontal ligament and the bone. The “no attachment” model was characterized by the lowest amount of desired translation on the y-axis and by the highest undesired distal tipping movement. In the rectangular attachment model, the tooth moved significantly more along the y-axis, with a smaller component of tipping and distal rotation. In the guided attachment model, the amount of movement along the y-axis was similar; however, there was the smallest range of undesired movements in the form of tipping or rotation. PDL was the point stress concentration in the first 2 groups, while in the guideline attachment group, the stress was equally distributed. |
Cortona et al. 2020 [23] | Finite element analysis | The influence of attachment positioning on movement efficiency (molar rotation) |
| The model with a single attachment on 45 and 1.2 degrees of aligner activation was the most efficient, followed by the three-attachment model (at the same degree of activation).Aligner activation should not exceed 1.2 degrees to achieve good control of movement and reasonable stress in periodontal structures. |
Costa et al. 2020 [24] | In vitro experimental study | The influence of attachment shape and positioning on movement efficiency (incisor extrusion) | Three models were designed to evaluate which attachment design enables the most effective upper incisor extrusion
| Different attachment geometries generate forces with significantly different intensities and directions. The third attachment had the best mechanical performance among the three models evaluated for extrusion. |
Dai et al. 2019 [25] | Randomized controlled clinical trial | The influence of attachment shape and positioning on movement efficiency (premolar extraction space closure) |
| G6-optimized attachments, together with horizontal attachments, showed similar efficacy and control in molar angulation. The vertical attachment had the biggest difference between the planned and achieved tooth movement and showed the worst anchorage control (the highest degree of molar tipping). |
Dasy et al. 2015 [26] | In vitro experimental study | The influence of attachment shape on aligner retention |
| The use of beveled attachments significantly increased retention. Ellipsoid attachments showed no significant effect on aligner retention with regard to an aligner with no attachments. |
Fan et al. 2022 [27] | Finite element analysis | The influence of attachment positioning on movement efficiency (molar intrusion) |
| The presence of an attachment is essential for clear aligners to intrude on the molars. Combined buccal and palatal attachments could effectively prevent buccal and palatal tipping and showed the best efficiency in terms of intruding on the molars. The second molar showed an unavoidable tendency to tip mesially, regardless of the attachment position. Thus, double attachment is advisable. |
Ferlias et al. 2022 [28] | In vitro experimental study | The influence of attachment shape and positioning on movement efficiency (premolar rotation) | A total of 11 different types of attachment and one with no attachment
| The rotations above 1° generate moments that are too high from a clinical point of view. Aligner steps of no more than 1–1.5° should be recommended for effective derotation of a premolar. The vertical rectangular attachments perform best when derotating a premolar due to their large flat active surface but receive the most side effects in terms of tipping, torque and intrusive force. Derotation of a premolar without any attachment was less efficient despite showing the least side effects. When a premolar was mesially rotated, the attachment producing the highest intrusive force was 3Shape. When the tooth was rotated distally, most attachments again received an intrusive force, while the 3Shape attachment displayed an extrusive force. When the tooth was rotated mesially, all setups received a buccal root torque, with the highest seen with the vertical rectangular attachment and the smallest with the beveled one. In the other direction, for the distally rotated tooth, a moment of lingual root torque was observed in all setups. |
Garino et al. 2016 [29] | Randomized clinical trial | The influence of attachment shape and positioning on movement efficiency (molar movement along a different axis) | A total of 30 non-growing patients in need of distalization after third-molar extraction.
| Although the groups did not differ in the amount of distalization, minimizing distal crown tipping and preventing molar extrusion, minimizing anterior anchorage loss and reducing undesirable changes in lower facial height were more effective in patients with all five teeth bonded with attachments. This approach seems promising in patients in need of 2–3 mm of distalization. |
Gomez et al. 2015 [30] | Finite element analysis | The influence of attachment presence on stress distribution (canine distalization) |
| The displacement of the model with attachments was equivalent to typical distal bodily movement. The displacement of the model without attachments was equivalent to typical uncontrolled distal crown tipping, with almost no reaction of the root. |
Karras et al. 2021 [31] | Retrospective cross-sectional study | The influence of attachment type (optimized vs. conventional) on movement efficacy | Included a total of 120 teeth arches, from which 163 teeth qualified for optimized rotation attachments (43%): 72 conventional rotation attachments (19%), 81 optimized extrusion attachments (21%) and 66 conventional extrusion attachments (17%) | For all tooth movements and attachment types, the mean predicted values were significantly larger than the mean achieved values. The least accurate tooth movement was mandibular canine extrusion with a conventional attachment (16.1%). The most accurate tooth movement was the extrusion of the maxillary central incisor with a conventional attachment (73.9%), followed closely by the rotation of the maxillary premolar with an optimized attachment (72.8%). Overall, the optimized attachments enabled achieving better results in terms of rotation movement, while conventional attachments performed better in extrusion movements. |
Kim et al. 2020 [32] | Finite element analysis | The influence of attachment shape and positioning on movement efficiency and stress distribution (lower canine rotation) | A virtual model with two attachments on the lower canine. The shape of the attachment for rotation had a plane perpendicular to the direction of rotation with the surfaces to which the load was applied. The models were classified as having angles of 90 degrees, 65 degrees and 45 degrees to the attachment surface of the teeth. There were four types of attachments for the torque tested; four shapes were half round, half round at the cross-section, half round at the cross-and longitudinal sections, and a lower bevel of 45°. | A desirable stress distribution was observed when there was a high contact area between the attachment and the aligner. Torque control and intended movement were achieved when the attachments were positioned on the lingual surface rather than on the buccal surface of the canines; thus the attachment used in the aligner treatment of the rotated canine is a cylinder form bonded to the lingual surface of the canine. In intrusion, a better control of the movement is achieved by bonding attachments to both the buccal and lingual surfaces of the canine. |
Kravitz et al. 2008 [33] | Randomized clinical trial | The influence of attachment shape and positioning on movement efficiency (canine rotation) |
| Vertical, ellipsoid attachments and interproximal reduction do not significantly improve the accuracy of canine rotation with the Invisalign system. |
Laohachaiaroon et al. 2022 [34] | Finite element analysis | The influence of attachments shape on movement efficiency and stress distribution (upper central incisors extrusion) |
| When considering the incisal edge as a reference, the model with the horizontal rectangular attachment had the greatest extrusive movement (0.037991 mm) followed by the model with the ellipsoid attachment (0.037606 mm) and the model with the rectangular beveled attachment (0.036786 mm). The model without a composite attachment demonstrated little intrusive movement (0.000105 mm). The differences were very small and were not clinically significant. The stress patterns were also similar in all three attachment models. |
Rossini et al. 2020 [35] | Finite element analysis | The influence of attachment use on movement efficiency and stress distribution (maxillary second molar distalization) |
| The attachments are mandatory to control the bodily movement of a second molar. Attachments should be used to reinforce the anchorage units and to function as active units on sequential distalizing molars. The configuration of attachments in the whole segment, from the canine to the 2nd molar, represents the most promising model for Class II correction via maxillary molar distalization. |
Rossini et al. 2021 [36] | Finite element analysis | The influence of attachment presence on movement efficiency and stress distribution (incisors extrusion) |
| The presence of 3 mm rectangular horizontal attachments on the buccal or palatal surface of the upper incisors with additional rectangular vertical attachments in the lateral from the canine to the second molar seemed to produce the most efficient force system to extrude incisors with minimal aligner deformation. Standard attachments seem to be more accurate than optimized ones. The most efficient configurations showed the need for the use of attachments on posterior teeth in order to obtain better anchorage. |
Savignano et al. 2019 [37] | Finite element analysis | The influence of attachments on movement efficiency and stress distribution during upper incisors extrusion |
| The extrusion of an upper central incisor cannot be achieved without any attachment. There was no clear difference between the rectangular and ellipsoid attachments. The position of the attachment showed a stronger influence on the outcome compared to the shape (palatal instead of buccal). |
Simon et al. 2014 [38] | Retrospective cross-sectional study | The influence of attachment shape and positioning on movement efficiency (incisors torque, lateral teeth derotation and distalization) |
| The use of attachments can significantly improve the efficiency of planned tooth movement. However, clinically planned movements are rarely completed. The crucial factors that influence the efficiency of aligner therapy are patient compliance and the reasonable, split staging of planned moves <1.5° of rotation per aligner, 1° aligner for incisor torque and up to 0.25 mm/aligner for distalization. Invisalign treatment usually needs refinements to achieve planned positions of the teeth. |
Smith et al. 2022 [39] | Retrospective cross-sectional study | The influence of attachments on tooth movement efficiency (lower incisor tipping) | 66 lower incisors in 42 non-extraction aligner patients
| It is possible to move roots using Invisalign® but not as predictably as ClinCheck® suggests. Moreover, the average amount of root movement achieved was substantially less than predicted. Vertical rectangular attachments are recommended when a large range of root movement is planned. Attachments improve the possibility of translating the root apex. |
Takara et al. 2022 [40] | In vitro experimental study | The influence of attachment shape on aligner retention | A total of 22 different models with 11 different types of attachments were placed on the lateral incisors or the first premolars and included a model with no attachments | Attachments significantly increase aligner retention. The easiest way to remove an aligner is from the lingual side of the first molar. It is difficult to remove the aligner by trying to lift it in the area of the incisors. However, the attachment on the lateral incisor may not contribute to the gripping force of the aligner when it is removed by lifting on the labial surface of the upper first molar. The retention of the aligner is influenced by the height, width and angulation of the attachment. The retention is superior when the bevel angle is close to the right angle. |
Yokoi et al. 2019 [41] | Finite element analysis | The influence of attachment shape and positioning on movement efficiency (diastema closure) |
| The use of attachments limited unplanned root movement and tooth tipping, increasing the effectiveness of diastema closure. In the aligner used with the attachments, the incisor overlapped completely on the target position in FEM, meaning that the efficacy of movement was almost 100%. However, the attachment did not influence the initial movement of the tooth, showing significant differences with an ongoing time simulation. |
Question | Ahmed et al. 2022 [21] | Ayidağa et al. 2021 [22] | Cortona et al. 2020 [23] | Fan et al. 2022 [27] | Gomez et al. 2015 [30] | Kim et al. 2020 [32] | Laohachaia-Roon et al. 2022 [34] | Rossini et al. 2020 [35] | Rossini et al. 2021 [36] | Savigniano et al. 2019 [37] | Yokoi et al. 2019 [41] | |
---|---|---|---|---|---|---|---|---|---|---|---|---|
Study Design and Presentation of Findings | ||||||||||||
1 | Was the hypothesis/aim/objective of the study clearly described? | Yes | Yes | Yes | Yes | Yes | Yes | Yes | Yes | Yes | Yes | Yes |
2 | Were all analyses planned at the outset of the study? Answer NO for unplanned analysis/sub-analysis, unable to determine. | Yes | Yes | Yes | Yes | Yes | Yes | Yes | Yes | Yes | Yes | Yes |
3 | If data dredging (establish objectives, hypothesis and endpoint parameters without scientific reason) was used, was the spectrum of the data justified by any concepts? Answer YES if no data dredging, NO if unable to determine | Yes | Yes | Yes | Yes | Yes | Yes | Yes | Yes | Yes | Yes | Yes |
4 | Were all the outcome measures and parameters (including all data reduction methods or derived parameters) clearly described and defined in the Objectives or Methods section? Answer NO if they are only defined in results or discussion | Yes | Yes | Yes | Yes | No | Yes | Yes | Yes | Yes | Yes | Yes |
5 | Were the time points or period for all the outcome measures clearly described? Answer YES if not applicable | No | No | Yes | Yes | Yes | No | Yes | Yes | Yes | Yes | Yes |
6 | Were the main outcome measures appropriate to describe the targeted conditions? Answer NO if unable to determine | Yes | Yes | Yes | Yes | Yes | Yes | Yes | Yes | Yes | Yes | Yes |
7 | Were the key findings described clearly? | Yes | Yes | Yes | Yes | Yes | Yes | Yes | Yes | Yes | Yes | Yes |
8 | Were all the contour plots that were used for comparison presented with the same color scale? | Yes | Yes | Yes | Yes | Yes | Yes | Yes | Yes | Yes | Yes | Yes |
Subject Recruitment | ||||||||||||
9 | Were the characteristics of the model subject clearly described? | Yes | Yes | Yes | Yes | Yes | Yes | Yes | Yes | Yes | Yes | Yes |
10 | Were the principal confounders of the model subject clearly described? | Yes | Yes | Yes | Yes | Yes | Yes | Yes | Yes | Yes | Yes | Yes |
11 | Was the model subject participated in the study representative of the population with the targeted clinical conditions or demographic features? (e.g., answer NO if simulating a pathology by modifying a normal subject model; or scaling an adult model to a child model) | Yes | Yes | No | Yes | Yes | Yes | Yes | Yes | Yes | Yes | Yes |
12 | Were the targeted intervention or clinical condition clearly described? | Yes | Yes | No | Yes | Yes | Yes | Yes | Yes | Yes | Yes | Yes |
Model Reconstruction and Configuration | ||||||||||||
13 | Was the model reconstruction modality for the body parts and all other items, such as implants, clearly described (e.g., MRI, 3D-scanning, CAD)? | Yes | Yes | No | Yes | No | Yes | Yes | Yes | Yes | Yes | Yes |
14 | Were all important technical specifications (e.g., resolution) for the reconstruction modality clearly described? | Yes | Yes | Yes/No—material described clearly, but not mandibular model | No | No | Yes | Yes | Yes | Yes | Yes | Yes |
15 | Was the posture or position of the body parts controlled during the acquisition process (e.g., MRI, CT) of the model reconstruction? | Yes | Yes | No | No | No | Yes | No | Yes | No | Yes | No |
16 | Were the model reconstruction methods for all components clearly described including those requiring additional procedures (e.g., connecting points for drawing ligaments from MRI)? | No | No | Yes/No | Yes | Yes | Yes | No | Yes | No | Yes | No |
17 | Were the orientation or relative position among the components of the model assembly (where appropriate) clearly described? Answer YES if not applicable | Yes | Yes | Yes | Yes | Yes | Yes | No | Yes | No | Yes | No |
18 | Was the type of mesh for all components, including the order of magnitude of the elements, clearly described? | No | Yes | No | Yes | Yes | Yes | Yes/No | No | No | Yes | Yes |
19 | Were the material properties for all components clearly described and justified? (e.g., with reference) | Yes | Yes | No | Yes | Yes | Yes | Yes | No | No | Yes | Yes |
20 | Were all the contact or interaction behaviours in the model clearly described and justified? | Yes/No | Yes | Yes/No | Yes | Yes | Yes | Yes | Yes | Yes | Yes | Yes |
Boundary and Loading Condition (Simulation) | ||||||||||||
21 | Were the boundary and loading conditions clearly described? | Yes | Yes | Yes | Yes | Yes | Yes | No | No | No | Yes | Yes |
22 | Was the boundary and loading condition sufficiently simulating the common activity/scenario of the conditions? (e.g., if the research or inference is targeted to ambulation or daily activities, simulations of balanced standing or pre-set compressive load are insufficient) | Yes | Yes | Yes | No | Yes | Yes | No | No | No | Yes | Yes |
23 | Was the model driven by the boundary condition acquired from the same model subject? | Yes | Yes | Yes | Yes | Yes | Yes | No | No | No | Yes | Yes |
24 | Was loading condition on the scenario sufficiently and appropriately considered in the simulation? (e.g., muscle force, boundary force, inertia force) | Yes/No | Yes/No | Yes | Yes | Yes | Yes | No | Yes | Yes | Yes | Yes |
25 | Was the loading condition acquired from the same model subject? | Yes | Yes | Yes | Yes | Yes | Yes | No | Yes | Yes | Yes | Yes |
26 | Was the software (e.g., Abaqus, Ansys), type of analysis (e.g., quasi-static, dynamic), and solver (e.g., standard, explicit) clearly described? (Solver can be regarded as clearly described if it is obvious to the type of analysis) | Yes | Yes | Yes | Yes | Yes | Yes | No | Yes | Yes | Yes | Yes |
Model Verification and Validation | ||||||||||||
27 | Were the methods of mesh convergence or other verification tests conducted and clearly described? | Yes | Yes | Yes | No | Yes | No | No | Yes | Yes | Yes | No |
28 | Were the model verification conducted and results presented clearly, and that the model was justified acceptable? | Yes | Yes | No | No—just mentioned carrying them out | Yes | Yes | No | Yes | No—just mentioned carrying them out | Yes | No |
29 | Was direct model validation (with experiment) conducted and described clearly? Answer YES if the authors had direct model validation previously with reference. | Yes | Yes | Yes | No | Yes | No | No | Yes | Yes | Yes | No |
30 | Were the model validation conducted and results presented clearly, and that the model was justified acceptable? | Yes | Yes | No | Yes/No | Yes | No | No | Yes | Yes | Yes | Yes |
31 | Were the model prediction or validation findings compared to relevant studies? | Yes | Yes | Yes | No | Yes | No | No | Yes | Yes | Yes | Yes |
Model Assumption and Validity | ||||||||||||
32 | Were the model assumptions or simplifications on model reconstruction/configuration and material properties discussed? | Yes | Yes | No | Yes | Yes | Yes | Yes | Yes | No | Yes | No |
33 | Were the model assumptions or simplifications on the boundary and loading conditions discussed? | Yes | Yes | Yes/No | Yes | Yes | Yes | Yes | Yes | No | Yes | No |
34 | Were the limitations of model validation discussed? (e.g., differences in case scenario; differences between validation metric and primary outcome) | No | Yes | No | Yes/No | Yes | No | No | Yes | No | Yes | Yes |
35 | Was the limitation on external validity, single-subject, and subject-specific design discussed? | Yes | Yes | No | No | Yes | Yes | No | Yes | No | No | Yes |
36 | Were there any attempts to improve or discuss internal validity (such as the mesh convergence test), uncertainty and variability in the study? | Yes | Yes | Yes | No | Yes | No | No | Yes | Yes | Yes | No |
37 | Was there any discussion, highlights or content on the implications or translation potential of the research findings? Answer NO if there are only bold claims without making use of the result findings or key concepts | Yes | Yes | Yes | Yes | Yes | Yes | No | Yes | Yes | Yes | Yes |
Sum: | 33.5 | 34.5 | 24.5 | 26.5 | 33 | 30 | 18.5 | 32 | 24 | 36 | 28 |
Criteria No. | Criteria | Alsaud et al. 2022 [16] | Chen et al. 2021 [18] | Costa et al. 2020 [24] | D’Antò et al. 2019 [19] | Dasy et al. 2015 [26] | Ferlias et al. 2022 [28] | Takara et al. 2022 [40] | Valeri et al. 2022 [20] |
---|---|---|---|---|---|---|---|---|---|
1 | Clearly stated aims/objectives | 2 | 2 | 2 | 2 | 2 | 2 | 2 | 2 |
2 | Detailed explanation of sample size calculation | 2 | 2 | 0 | 2 | 0 | 0 | 0 | 0 |
3 | Detailed explanation of sampling technique | 2 | 2 | 2 | 2 | 1 | 1 | 2 | 2 |
4 | Details of comparison group | 2 | 2 | 1 | 2 | 2 | 2 | 2 | 2 |
5 | Detailed explanation of methodology | 2 | 2 | 1 | 2 | 2 | 2 | 2 | 2 |
6 | Operator details | 0 | 1 | 0 | 2 | 0 | 2 | 2 | 2 |
7 | Randomization | 0 | 1 | 0 | 0 | 0 | 0 | 0 | 0 |
8 | Method of measurement of outcome | 2 | 2 | 2 | 2 | 2 | 2 | 2 | 2 |
9 | Outcome assessor details | 2 | 2 | 2 | 2 | 1 | 1 | 2 | 0 |
10 | Blinding | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
11 | Statistical analysis | 2 | 2 | 2 | 2 | 2 | 2 | 2 | 2 |
12 | Presentation of results | 2 | 2 | 2 | 2 | 1 | 2 | 2 | 2 |
Bruno et al. 2021 [21] | Dai et al. 2019 [25] | Garino et al. 2016 [29] | Kravitz et al. 2008 [33] | |
---|---|---|---|---|
Random sequence generation | LOW | SOME CONCERNS | LOW | LOW |
Allocation concealment | LOW | HIGH | LOW | SOME CONCERNS |
Blinding of participants and personnel | HIGH | HIGH | HIGH | HIGH |
Blinding of outcome assessment | SOME CONCERNS | HIGH | SOME CONCERNS | HIGH |
Incomplete outcome data | LOW | LOW | LOW | LOW |
Selective reporting | LOW | LOW | LOW | HIGH |
Other bias (why) | The bias comes from the difference between the bonding procedure and analyzing the data, as the templates and attachments differ from each other | Great loss to follow-up | The bias comes from the difference between the bonding procedure and analyzing data, as attachments are noticeable in the mouth | The pretreatment model was obtained by the indirect and direct methods, resulting in an uneven level of accuracy. |
Risk of bias judgement | SOME CONCERNS | HIGH | SOME CONCERNS | HIGH |
Study | Karras et al. 2021 [31] | Simon et al. 2014 [38] | Smith et al. 2022 [39] | |
---|---|---|---|---|
Selection | Representativeness of the cases | * | * | * |
Justified sample size | * | 0—not justified | * | |
Non-respondents | * | * | * | |
Ascertainment of the exposure (risk factor) | ** | * | ** | |
Comparability | The subjects in different outcome groups are comparable based on the study design or analysis. The confounding factors are controlled | ** | ** | ** |
Yes, the group was homogenous regarding the studying phenomena | Yes, the group was homogenous regarding the studied phenomena | Yes, the group was homogenous regarding the studied phenomena | ||
Outcome | Assessment of the outcome | ** | ** | ** |
Statistical test | * | * | * | |
Total | 10 | 8 | 10 |
Tooth | Movement | Attachment Type and Position | Example of Attachment in Orthodontic CAD Software [42] |
---|---|---|---|
Upper incisors | Retrusion/intrusion/extrusion | Conventional, rectangular, beveled, horizontal attachments, preferably placed on the palatal surface and preferably with auxiliary attachments on the posterior teeth | |
Upper incisors | Diastema closure | Double contrary, sassy attachments on the labial surfaces of the central incisor | |
Lower incisors | Intrusion/extrusion | Conventional, rectangular, beveled, horizontal attachments, preferably placed on the palatal surface and preferably with auxiliary attachments on the posterior teeth | |
Lower incisors | Tipping | Conventional, rectangular, vertical attachments, preferably placed on the palatal surface | |
Canine | Intrusion/Extrusion | Optimized, one-side-beveled attachment | |
Canine | Distalization | Two ellipsoid sassy optimized attachment or beveled angled single optimized attachment, preferably placed together with conventional vertical attachments on adjacent teeth | |
Canine | Rotation | Conventional ellipsoid one-side-beveled attachment on lingual surface of the tooth/Conventional vertical beveled attachments on the lingual and buccal surfaces of the tooth | |
Premolar | Rotation | Vertical rectangular attachments/optimized vertical attachments | |
Molar | Intrusion/extrusion | Two conventional vertical attachments—one on the palatal surface, one on the buccal surface/optimized vertical attachments | |
Molar | Mesialization | Optimized horizontal attachment | |
Molar | Rotation | Three vertical 3 mm attachments placed on the buccal surfaces of the teeth to be rotated and the adjacent teeth | |
Molar | Distalization | Preferably, conventional 3 mm vertical or optimized attachment on the second molar placed together with conventional (preferably vertical) attachments from the canine to the second molar | |
Molar | Distalization+ Distorotation | Vertical 3 mm attachment placed on the buccal surface | |
Molar | Uprighting | Horizontal 3 mm attachment located on the buccal surface at an angle of 45° |
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© 2023 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https://creativecommons.org/licenses/by/4.0/).
Share and Cite
Jedliński, M.; Mazur, M.; Greco, M.; Belfus, J.; Grocholewicz, K.; Janiszewska-Olszowska, J. Attachments for the Orthodontic Aligner Treatment—State of the Art—A Comprehensive Systematic Review. Int. J. Environ. Res. Public Health 2023, 20, 4481. https://doi.org/10.3390/ijerph20054481
Jedliński M, Mazur M, Greco M, Belfus J, Grocholewicz K, Janiszewska-Olszowska J. Attachments for the Orthodontic Aligner Treatment—State of the Art—A Comprehensive Systematic Review. International Journal of Environmental Research and Public Health. 2023; 20(5):4481. https://doi.org/10.3390/ijerph20054481
Chicago/Turabian StyleJedliński, Maciej, Marta Mazur, Mario Greco, Joyce Belfus, Katarzyna Grocholewicz, and Joanna Janiszewska-Olszowska. 2023. "Attachments for the Orthodontic Aligner Treatment—State of the Art—A Comprehensive Systematic Review" International Journal of Environmental Research and Public Health 20, no. 5: 4481. https://doi.org/10.3390/ijerph20054481