Comparative evaluation of accuracy of the orthodontic treatment outcome in predicted and achieved results using clear aligners: A prospective clinical study

INTRODUCTION

Malocclusion, or deviation from an optimal occlusion, affects many children and adolescents, affecting dentofacial growth, function, and tooth damage. It also impacts psychological well-being, self-esteem, and self-image. Malocclusion significantly impacts teenagers and young adults, prompting them to avoid situations to alleviate the discomfort and negative emotions related to the condition. Conforming to societal norms is the primary motivation for seeking orthodontic treatment, as it can negatively impact their quality of life. Clear aligner therapy, introduced by Align Technology, has revolutionized orthodontics with its transparent, polyurethane splints capable of correcting tooth movements discreetly.^[1,2]

Clear aligners offer esthetic advantages, improved oral hygiene, and reduced decay incidence compared to conventional treatments. The aligners are designed to move teeth gradually within 2 weeks, requiring excellent patient compliance. Various generations of aligners have evolved, introducing attachments and features to address complex malocclusions.^[3-5]

The historical development of clear aligners, from Dr. Harold Kesling’s thermoplastic tooth positioners in 1946 to the founding of Align Technology in 1997, has undergone multiple generations, incorporating advancements such as power ridges, precision cuts, and smart force attachments.^[6-9]

The material used in clear aligners plays a crucial role in treatment efficacy. Thermoplastic materials such as Polyethylenterephthalat-Glycol (PET-G), polypropylene polycarbonate (PC), thermoplastic polyurethanes (TPU), and ethylene acetate are commonly used, with PET-G being favored for its transparency and formability. The thickness, activation, and stiffness of the material influence the force exerted on teeth during treatment. The effectiveness of clear aligners is attributed to their semi-elastic polyurethane material, offering various tooth movements such as translation, rotation, extrusion, intrusion, torque, and uprighting. Thus, the benefits of using clear aligners over traditional fixed orthodontics include better esthetics, comfort, and improved periodontal health.^[3,5,10,11]

The fabrication of clear aligners involves manual processes or computer aided design and manufacturing (CAD-CAM) technology. The latter, utilizing digital impressions and virtual treatment planning, has become the preferred method for its precision. The aligner treatment’s success depends on the properties of the material and factors such as patient compliance and clinical experience.^[12-14]

Clear aligner treatments come with certain limitations: First, patient compliance is critical. Since the aligners are removable, the orthodontist must rely on the patient’s motivation and reliability to achieve desired outcomes. All permanent teeth must be fully erupted before starting treatment with these appliances. Basal orthopedic changes cannot be achieved with this system, and both hard and soft tissues of the cranium cannot be treated using these techniques. Therefore, clinicians lack a clear understanding of the position of teeth in relation to the basal bone, lips, and other soft tissues of the head. Major restorative work should be completed before beginning treatment, as changes to the surface architecture of the teeth during treatment can affect the fit of the aligners. Insufficient operator control and the inability to integrate computer treatment into the hard and soft tissues of the cranium are significant drawbacks of this treatment. Consequently, clinicians lack a clear indication of the position of teeth in relation to the basal bone.^[7,8]

A critical review of prior studies (Djeu et al. [2005],^[15] Tepedino et al. [2018],^[16] Karras et al. [2021]^[17]), highlights that most research has focused on retrospective or in vitro data, with limited prospective evaluation comparing predicted versus achieved clinical outcomes. Our study provides a prospective, clinically validated comparison of digital predictions and actual treatment results, addressing this gap.

For aligner treatment to be valid and effective, the predicted and achieved results should be comparable. The digital setup provides a complete vision of the treatment plan at the beginning, reflecting the treatment outcome and allowing the anticipated result to be envisioned. There is a lack of literature quantifying the deviation between clinical results and predictions for clear aligners. No studies compare clinical treatment outcomes to predictions. Understanding the effectiveness of clear aligners in the rapidly expanding market is essential. Therefore, it is crucial to evaluate and compare the clinical and expected therapeutic outcomes of clear aligners. This study aims to compare the accuracy of orthodontic treatment outcomes in predicted and achieved results using clear aligners.^[18]

MATERIAL AND METHODS

• Sample size: 20 patients

• Sample size formula: $n=z^2\frac{pq}{{\left(me\right)}^2}$

• Study design: Prospective clinical study.

n - Required sample size.

z - z-score or value corresponding to the desired confidence level.

p - Estimated population proportion.

q - Represents (1-p), the complement of the estimated population proportion or the estimated proportion of the population that does not possess the attribute of interest.

me - Margin of error.

After ethical clearance, 20 patients were selected for clear aligner therapy from the outpatient department of our institute. The study group comprised 20 adult participants with an age group of 18–35 years, with an average age of 22 years (7 males and 13 females). The patients who fulfilled the inclusion criteria were selected for the study.

The inclusion criteria for this study were male and female subjects of age 18–35 years, subjects with a complaint of spacing in the anterior region of either arches (2–10 mm), subjects with good compliance, normal/minimal overbite, no midline deviations, and subjects providing a valid informed consent.

The exclusion criteria: Subjects with missing 1^st molars, unwillingness to give informed consent, any history of systemic disorders, presence of anterior or posterior crossbite, allergy to polyvinyl siloxane impression material, and severe crowding in either of the arches. Furthermore, a subject withdrawal criterion was also included for subjects who were unwilling to participate in further study, and loss of the subject follow-up due to certain circumstances.

All records of the 20 individuals were obtained, such as (a) Lateral cephalogram, (b) Orthopantomogram (OPG), (c) Intraoral and extraoral photographs, (d) Maxillary and mandibular impressions were recorded using Addition Silicone impression material (Light body putty), (e) Study models (using Orthokal plaster). After collecting all the records, the Open Technology Lab scanner (Desktop 3D scanner) was used to scan the study model and create a virtual model of the study model. Autoalign Software (Version 1.6.4.0 2021) was used for treatment planning, and once the treatment plan was approved, the Phrozen Sonic Mini 4k 3D printer was used for printing the models, and the Biostar thermoforming machine was used for aligner fabrication using the “Duran thermoplastic material.” At the end of the treatment, Geomagic Software Control X 2020 (Version 1.1) was used for the superimposition of the predicted and achieved models.

Methodology

The study involved a comprehensive pre-treatment analysis of all the records, including impressions, OPG, lateral cephalograms, intra-oral and extra-oral photographs, and study models. Patients who matched the inclusion criteria were selected for the study. The procedure involved recording the impressions of both arches using addition silicon polyvenylsiloxine impression material (light body putty). Two sets of impressions were taken, one as a study cast model and one for scanning for the aligner fabrication. Orthokal plaster was used to make a negative replica of the impressions. The occlusion registration was taken for articulating maxillary and mandibular models.

The Open Technology 3D scanner (Italy) was used to create a 3D virtual model of a cast. The scan data was generated in native or proprietary formats and meshed for usability outside the scanner/CAD workflow. The Autolign software, provided by DIORCO (Digital Orthodontic Company, South Korea), is the world’s first real-time collision detection technology, enabling instant consultation and virtual set-up.

The model is prepared, segmented, and virtual setups are performed. The software allows for multiple treatment methods and tooth movements. The software also checks the animation of tooth movements and compares pre-treatment and post-treatment models. After segmentation, an automatic model analysis is generated, and a treatment analysis report is generated. The software then stimulates a treatment plan, and a virtual model was fabricated for the production of aligners. The number of aligners to be given to the patients was predicted by the software individually for the maxilla and mandible. The predicted aligners were given according to the tooth movements and the designed treatment plan.

The Phrozen Sonic Mini 4k 3D printer was used to make detailed 3D printed parts. The printer works best with Phrozen Aqua-Gray 4k resin. A virtual model was printed using the printer, and plastic models were created using stereolithography. Aligners were built using the thermoforming technique using the Biostar thermoforming machine, a universal pressure molding device.

The study created aligners using Duran thermoplastic material and a Biostar thermoforming machine based on predicted tooth movements. Participants were given these aligners to wear consistently throughout treatment. Post-treatment records were recorded using the same procedure as the pre-treatment records.

A 3D scan of the study cast model was created, and the predicted and achieved models were superimposed using the first molars. Autolign software was used for treatment planning, and Geomagic Control X 2020 1.1 software was used for superimposition of reference and measured data [Figure 1]. Incisal edges and cusp tips were used as reference points for recording the linear measurement.

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Figure 1:

(a) Addition silicone impression of upper and lower arch. (b) Process of Scanning Plaster Model in Open Technology Lab Scanner. (c) Autolign Software (Version 1.6.4.0 2021) (Showing superimposition of models; White illustrates models before the planning, and green color illustrates model after the planning). (d) Virtual setup: Planning of tooth movements for space closure. (e) Phrozen Sonic Mini 4k 3D printer with resin used for 3D printing. (f) Duran Thermoplastic Sheets for aligner fabrication. (g) Biostar Thermoforming Machine. (h) 3D Printed Model along with upper and lower aligners. (i) 3D Compare (Upper Models) (Geomagic Control X 2020 1.1 software).

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Horizontal changes are the labiolingual movements of the teeth. These movements involve the teeth moving toward the lips (labial) or toward the tongue (lingual). The labial and lingual surfaces of the teeth are considered when checking for these horizontal changes after superimposition of achieved and predicted results. The precision of horizontal tooth movements was evaluated specifically for anterior teeth (canine, lateral incisor, and central incisor) in both the maxillary and mandibular arches.

Vertical changes are the extrusion and intrusion of teeth. Extrusion refers to the movement of a tooth out of the jawbone, while intrusion refers to the movement of a tooth into the jawbone. The incisal edges of teeth were used as a reference to record vertical changes in both the maxilla and mandible after superimposition of reference and measured data. Similar to horizontal changes, the precision of vertical tooth movements was evaluated for anterior teeth.

Transverse changes are evaluated by measuring changes in the intercanine width and interpremolar width in both the maxillary and mandibular arches after superimposition of the reference and measured data. The cusp tips of canines and the central pits of premolars and molars were used to measure these transverse changes [Figure 2].

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Figure 2:

(a) Vertical changes (Extrusion and Intrusion) (Upper), after superimposition of the reference and measured data. (b) Horizontal changes (Labiolingual movement) (Upper), after superimposition of the reference and measured data. (c) Transverse changes (Upper) after superimposition of the reference and measured data (intercanine width, interpremolar width, and intermolar width). (d) Vertical changes (Extrusion and Intrusion) (Lower), after superimposition of the reference and measured data. (e) Horizontal changes (Labiolingual movement) (Lower), after superimposition of the reference and measured data. (f) Transverse changes (Lower) after superimposition of the reference and measured data (intercanine width, interpremolar width, and intermolar width).

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Measurements were taken on each patient, and 222 teeth were examined for changes in the horizontal, vertical, as well as transverse directions. The precision of tooth movements in the horizontal and vertical directions was evaluated only for anterior teeth (Canine, Lateral Incisor, and Central Incisor) in arches. The molars were kept as a stable location for superimposition. Premolars and canines were used to determine accuracy in the transverse direction. By contrasting the anticipated and actual tooth movements, accuracy was evaluated. The measurement was made in 50 mm. A comparison point was selected to measure the changes. The comparison point consists of coordinates such as x, y, z [Figure 3].

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Figure 3:

3D Compare, comparison point consisting of coordinates such as x, y, z (Geomagic Control X 2020 1.1 software). X axis - Horizontal changes are the labiolingual movements of the teeth. These movements involve the teeth moving toward the lips (labial) or toward the tongue (lingual). Y axis - Vertical changes are the extrusion and intrusion of teeth. Extrusion refers to the movement of a tooth out of the jawbone, while intrusion refers to the movement of a tooth into the jawbone. Z axis - Transverse changes are evaluated by measuring changes in the intercanine width and interpremolar width in both the maxillary and mandibular arches after superimposition of the reference and measured data.

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The discrepancy between the achieved and predicted measurements will determine the accuracy of the treatment outcome. The gap distance of all the individual teeth was measured, which signifies the linear measurement between the predicted and achieved models. They were denoted as positive or negative values. Positive values indicated that the tooth has moved labially or extruded, and negative values indicated that the tooth has moved lingually or intruded to close the spaces in the anterior region. Deviation or discrepancy between the predicted and achieved results was noted.

Percentages were used to calculate the treatment outcome’s overall accuracy. The units of measurement were both in mm as well as in percentage.

A consolidated standards of reporting trials (CONSORT) diagram has been incorporated to illustrate the participant flow and study design for the clinical evaluation of clear aligner therapy [Diagram 1].

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Diagram 1:

CONSORT diagram

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RESULTS

The study evaluated the effectiveness of clear aligner therapy in orthodontic treatment outcomes for both the maxilla and mandible. The overall mean accuracy of the treatment was 68%, with the maxilla showing a higher mean accuracy (70.42%) compared to the mandible (66.35%) [Graph 1]. Significant differences were observed in the intercanine width deviation between the maxilla and mandible, with higher values in the maxilla. However, there were non-significant differences in interpremolar and intermolar width deviation between the two groups. This suggests that, on average, the clear aligner treatment achieved the planned transverse movements without significant deviations [Graph 2].

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Graph 1:

Comparison of mean accuracy percentage of orthodontic treatment outcome in maxilla and mandible.

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Graph 2:

Comparison of the mean value of gap distance between predicted and achieved intercanine, interpremolar and intermolar width in maxilla and mandible.

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Predicted and achieved maxillary and mandibular intercanine, interpremolar, and intermolar widths showed no statistically significant differences. Similarly, there were non-significant differences in horizontal and vertical movements of teeth in relation to the maxillary and mandibular arch. However, highly significant differences were found in predicted and achieved vertical changes, with higher values for intrusion compared to extrusion, especially in central incisors, lateral incisors, and canines [Graph 3].

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Graph 3:

Mean comparison of predicted and achieved vertical changes in maxillary and mandibular central incisors, lateral incisors, and canine.

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The study also revealed highly significant differences in predicted and achieved horizontal changes, with higher values for labial movement compared to lingual movement in central incisors, lateral incisors, and canines [Graph 4]. Overall, the results suggest that clear aligner therapy was more effective in achieving desired outcomes in the maxilla compared to the mandible, and there were notable variations in tooth-type-specific vertical and horizontal changes [Figure 4].

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Graph 4:

Mean comparison of predicted and achieved horizontal changes in maxillary and mandibular central incisors, lateral incisors, and canine.

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Figure 4:

(a) Pre-treatment (front), (b) Pre-treatment (right), (c) Pre-treatment (left), (d) Pre-treatment (maxillary occlusal), (e) Pre-treatment (mandibular occlusal), (f) Post-treatment (front), (g) Post-treatment (right), (h) Post-treatment (left), (i) Post-treatment (maxillary occlusal), (j) Post-treatment (mandibular occlusal).

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DISCUSSION

Malocclusion, a common issue in children and adolescents, affects dentofacial growth, function, and psychological well-being. Dissatisfaction with dental appearance drives many to seek orthodontic treatment, often motivated by esthetic concerns and societal norms. Clear aligners, a modern alternative to traditional braces, have gained popularity due to their esthetic appeal, improved oral hygiene, and patient comfort. Made from transparent polyurethane using CADCAM technology, they gradually correct tooth position with strict compliance required for effective results. Their rise reflects the growing demand for discreet orthodontic solutions.^[1,2]

There had not been much research directly comparing the clinical treatment outcomes achieved with clear aligners to the outcomes predicted by the treatment plan. Therefore, it was considered essential to evaluate and compare the clinical and expected therapeutic outcomes of clear aligners in the rapidly growing market for these appliances. Treatment planning software plays a crucial role in planning clear aligner treatments and offers several advantages such as: it is used to evaluate and determine the final results, serves as an effective computerized treatment-planning tool that allows the clinician to determine the sequence of tooth movement, final tooth locations, and final occlusion, enables virtual and computerized treatment planning, allowing the clinician to modify individual tooth positions, add and remove conventional attachments and precision cuts, and adjust the amount of interproximal reduction (IPR), enables the orthodontist to see the treatment from all angles and superimpose one stage of treatment over another to visualize individual tooth movements to assess the feasibility of the planned movement. Duran is a thermoplastic material made of PET-G. Duran thermoplastic sheets of 0.8 mm thickness made of Duran (Scheu Dental, Iserlohn, Germany) were thermoformed on the 3D-printed models of the patients’ teeth using a Biostar pressure moulding device (Biostar^®;Scheu Dental, Iserlohn, Germany). The study conducted by Dalaie et al. concluded that thermomechanical properties were significantly reduced due to thermoforming more than aging, and critically, the thermomechanical stability of Duran was found to be greater than Erkodur, which is why Duran was used in this study.^[8,12,14,18]

Clearly, successful aligner therapy is not confined to aligners alone; other adjuncts and auxiliaries should be used to expand the frontiers of aligners in treating patients with complex or unique malocclusions. These variables affect the clinical result of the aligners anticipated and lessen the CAT’s mean accuracy.^[19]

The efficiency of tooth movement, on the other hand, is strictly related not only to the virtual setup but also to the mechanical properties of the thermoplastic materials used in aligners and attachment design.^[20] Furthermore, using aligners in the oral cavity exposes the aligner to additional elements such as temperature, humidity, salivary enzymes, and elastic deformation, all of which can affect the physical and chemical properties of transparent aligners in patients’ mouths.^[21]

In our study, participants were told to wear the consecutive pair of aligners for 7 days. Rossini et al.^[22] addressed an Aligner change regimen identical to the one used in this investigation. He stated that the aligner change regime should be defined based on the movement that needs to be controlled during treatment: A 7-day protocol is generally sufficient for most movements, but molar torque control, lower canine and bicuspid rotation, torque control, and lower molars rotation require a 14-day aligner change.^[22]

Aligner fit and treatment simulation comparison are crucial in assessing the accuracy of predicted tooth movements and evaluating patient compliance.

In conclusion, these variables, along with the patient wearing aligners for the recommended duration, are essential to achieving the desired treatment outcome and should be carefully considered.^[23]

The overall mean accuracy of clear aligner therapy observed in this study was 68.38%. When considering the individual arches, the maxilla exhibited a statistically significantly higher mean accuracy of 70.42% compared to the mandible’s 66.35% (P < 0.01). This finding suggests a potentially greater predictability of tooth movement within the maxillary arch using clear aligners, possibly due to inherent differences in bone density, root morphology, or arch form compared to the mandible. This overall accuracy rate provides a valuable benchmark for clinicians and aligns with some existing research while differing from others, underscoring the ongoing need for comprehensive evaluations in this rapidly evolving field of orthodontics.

In examining the accuracy of specific tooth movements, the study found incisor intrusion to be the least predictable linear movement, displaying a statistically highly significant difference between the predicted and achieved outcomes (P < 0.01), particularly in the maxillary and mandibular central incisors. This observation corroborates findings from a study by Charalampakis et al.,^[18] which also identified incisor intrusion as a challenging movement with clear aligners. The lower accuracy of intrusion may be attributed to anchorage limitations inherent in the SmartForce protocol utilized in this study, where anchorage is considered in a later stage (since anchorage issues often become apparent as treatment progresses, they are managed after initial movements to ensure precise force control). Another study by Djeu, Karras and Buschang reported a similarly low accuracy (43.28%) for intrusion, further supporting the difficulty in achieving predictable intrusive movements with these appliances.^[15,17,24]

Conversely, incisor extrusion demonstrated a higher degree of accuracy, with no statistically significant differences observed between the predicted and achieved movements. This finding contrasts with some existing literature that suggests extrusion is also a less predictable movement with clear aligners. The study posits that the mechanics of aligner design, where forces are applied to attachment surfaces to facilitate extrusion, might contribute to the improved accuracy observed in this cohort. However, it is important to note that the extent of extrusion attempted in this study, which focused on minor crowding cases, might differ from studies involving more significant vertical discrepancies.^[25-27]

Regarding labiolingual movements, the study identified a statistically highly significant difference between predicted and achieved labial movement compared to lingual movement (P < 0.01), with labial movement exhibiting lower accuracy. The greatest variability in labial movement was noted in the maxillary and mandibular lateral incisors. This finding is consistent with the work of D’Antò et al., who reported greater accuracy for lingual constriction compared to labial expansion.^[23] The inherent design and material properties of clear aligners, which primarily bend in the buccolingual direction, may contribute to this disparity, potentially offering more controlled forces for lingual movements than for labial expansion.^[17,18]

There is a consensus that horizontal movements are generally more accurate than vertical movements. Furthermore, both the current study and D’Antò et al. found that lingual movement (constriction) is more accurate or predictable than labial movement (expansion).^[23]

In the transverse dimension, the achieved intermolar width displayed minimal deviation from the predicted values, with no statistically significant difference observed. However, a statistically significant difference was found in the gap distance of the intercanine width between the maxilla and mandible (P < 0.05), with higher values observed in the maxilla. This suggests that achieving precise intercanine width changes, particularly in the maxillary arch, might be less predictable than changes in intermolar width.

A similar study done by Charalampakis et al. (2018)^[18] found that the greatest difference was detected in the change in maxillary intercanine width, with the discrepancy in the maxillary arch being greater than in the mandibular arch. They also reported that interpremolar expansion was accurate. These findings suggest that the challenges are associated with maxillary canine movement (due to long roots and conical crown morphology).

An interesting observation in this study was the prevalence of achieved root parallelism among the treated patients. This suggests that clear aligner therapy in this cohort resulted in more tooth translation than tipping movements. However, the study acknowledges that achieving parallel roots can be more challenging in extraction cases due to the potential for undesirable tipping movements during space closure, as highlighted by other authors. As this study did not include extraction cases, the findings regarding root parallelism might not be generalizable to such treatment modalities.

Attachments play a key role in improving the predictability of tooth movement when using clear aligners, as they enhance grip and optimize force application. Although this study did not directly assess the effects of various attachment designs, it recognizes their expected positive contribution to treatment precision. In addition, the study emphasizes that anchorage was the last factor considered in the SmartForce protocol, a detail that may affect the accuracy of movements such as intrusion, where strong anchorage control is essential.^[19,26,27]

Several limitations inherent in the study design warrant consideration when interpreting the findings. The use of a multistep method for creating digital models, involving plaster casts from polyvinyl siloxane impressions followed by scanning, introduces a potential source of inaccuracy. Possible deformation or shrinkage of the impression material and the resolution limitations of the model scanner could have influenced the accuracy of the digital representations. The study acknowledges that the use of intraoral scanners, generally considered more accurate than traditional impression techniques, might have yielded different results.

Despite these limitations, this study provides valuable insights into the accuracy of clear aligner therapy for specific types of tooth movements in adult patients with minor crowding. The findings underscore the relative challenges in achieving predictable incisor intrusion and labial movements with this treatment modality. Clinicians should be cognizant of these limitations and may need to incorporate strategies such as overcorrection or adjunctive procedures when these movements are critical for the desired treatment outcome. The statistically significant difference in accuracy between the maxillary and mandibular arches also warrants consideration during treatment planning.

Future research should aim to address the limitations of this study by employing intraoral scanners for digital impression acquisition, including a broader range of malocclusion severities and patient demographics, and objectively quantifying patient compliance. Further investigations are also needed to evaluate the influence of different attachment designs, aligner materials, and anchorage protocols on the predictability of various tooth movements. Longitudinal studies utilizing more stable superimposition techniques, such as those based on cone-beam computed tomography, could provide a more comprehensive understanding of the three-dimensional changes achieved with clear aligner therapy. By addressing these areas, future research can further refine our understanding of the capabilities and limitations of clear aligners and contribute to evidence-based clinical practice in orthodontics.

CONCLUSION

The overall mean accuracy of the orthodontic treatment outcome in predicted and achieved results using clear aligners was 68.38%. The percentage accuracy of the orthodontic treatment outcome in the maxilla and mandible was 70.42% and 66.35%, respectively. The accuracy of the orthodontic treatment outcome in the maxilla was greater than the mandible. The overall horizontal and vertical movements predicted were achieved in all the patients who had undergone clear aligner therapy. No difference was observed between the predicted and achieved horizontal and vertical movements in relation to the maxillary and mandibular arches. Intrusion was the least accurate tooth movement with the largest gap distance when compared to extrusion in both the maxilla and mandible. Labial movement was the least accurate tooth movement with the largest gap distance when compared to the lingual movement in both maxilla and mandible. Thee accuracy was determined by the gap distance between the predicted and achieved models. The larger the gap distance, the lower the accuracy is. No differences were detected between the predicted and achieved transverse movements of teeth. Thee discrepancy in maxillary intercanine width change was greater than the discrepancy in mandibular intercanine width change. The greatest difference was found in the maxillary intercanine width change. The predictability of the transverse dimension showed that mandibular arch width is more predictable than the maxillary arch. There was no difference detected between the intercanine, interpremolar, and intermolar width of the predicted and achieved model. Superimposition of the models revealed a minimal/negligible amount of discrepancy in intercanine, interpremolar, and intermolar width, which was not significant. Clear aligner therapy was able to achieve predicted tooth positions with high accuracy in most of the given cases. This study was beneficial primarily because it aimed to address a lack of detailed literature comparing predicted and achieved clear aligner treatment outcomes in a quickly expanding market. By evaluating the accuracy of orthodontic treatment outcomes when using clear aligners and comparing predicted results from digital setups to the results actually achieved in patients, the study provided valuable insights for clinicians and contributed to the understanding of clear aligner therapy.