Abstract
Background
This study aimed to investigate how orthodontists’ clinical experience influences their treatment preferences and clinical strategies in clear aligner therapy (CAT). CAT has become increasingly widespread in contemporary orthodontic practice, largely due to its aesthetic appeal and the enhanced comfort it offers to patients, making it a preferred option among both orthodontists and patients. The reasons for the preference of CAT and the manner in which it is applied can vary significantly between orthodontists, especially in complex cases. The study was designed based on the assumption that one possible reason for these differences is the varying levels of clinical expertise among orthodontists.
Methods
A cross-sectional original, validated questionnaire was distributed to orthodontists in Türkiye. The questionnaire consisted of four main sections: (1) demographic information, (2) management of CAT, including clinical experience and clinical protocols, (3) types of patients treated and/or managed with CAT, and (4) perspectives of orthodontists who do not use CAT. Responses were analyzed using descriptive statistics and chi-square tests with effect sizes to explore associations between clinical experience and treatment-related variables.
Results
A total of 338 orthodontists completed the survey (response rate: 14.1%). Mild-to-moderate crowding was the most frequently treated condition. More experienced orthodontists reported significantly greater use of CAT in complex cases, including extractions and skeletal discrepancies. Clinical experience was also significantly associated with the use of adjunctive techniques, refinement frequency, and awareness of CAT limitations. Distalization was perceived as the most predictable advantage of CAT over fixed appliances, regardless of experience. Patient compliance was considered the most critical factor for success, whereas aligner brand had minimal impact.
Conclusions
Clinical experience appears to play a critical role in shaping orthodontists’ treatment decisions regarding CAT. Greater clinical exposure and structured training may expand orthodontists’ ability to manage complex malocclusions effectively with CAT, underscoring the importance of continued education and experience-based proficiency in achieving predictable and optimal outcomes.
Supplementary Information
The online version contains supplementary material available at 10.1186/s12903-025-07405-0.
Keywords: Clear aligners, Orthodontists, Experience, Preferences
Background
Advancements in orthodontic technology have led to the growing acceptance of CAT among both orthodontists and patients [1, 2]. Compared to conventional fixed appliances, CAT offer well-recognised advantages in aesthetics, comfort, and oral hygiene, making them a preferred option particularly for adults [3, 4]. Importantly, pediatric patients also show high acceptance of CAT; Invisalign First users report greater comfort and satisfaction compared with traditional removable appliances [5].
Although the first clear aligner systems were developed to address minor malocclusions, recent technological progress has enabled their use in more complex cases that require comprehensive orthodontic treatment [6]. Adjunctive techniques—such as temporary anchorage devices and corticotomy—have further expanded the scope of CAT, particularly in multidisciplinary treatment plans involving prosthodontic or orthognathic interventions [3]. However, despite these improvements, CAT may still lack sufficient precision in finishing stages, especially for root control, rotations, and anterior extrusion [6–10].
The increasing number of available CAT, combined with the limited and heterogeneous evidence in the literature, has resulted in clinicians relying heavily on their own clinical experience when planning CAT [9, 11–15]. No clear consensus exists on aligner system selection, treatable malocclusions, or the predictability of specific tooth movements.
Most of the studies conducted to date have evaluated orthodontists and general dentists who use CAT and have compared these practitioner groups [11, 14–18]. However, no data exist in the literature examining whether differences in clinical experience among orthodontists influence their perspectives on CAT and their treatment protocols. Moreover, data on orthodontists who do not use CAT remain limited, as do insights into the differences between provider and non-provider groups and the reasons behind their choices [3, 11, 16].
To address this gap, the present study investigates the impact of clinical experience—measured by years in practice and number of completed cases—on the use of CAT among Turkish orthodontists. It also explores orthodontists’ general treatment approaches and patient evaluations to provide a more comprehensive understanding of their perspectives on CAT. It was hypothesized that clinical experience significantly influences orthodontists’ approaches to CAT, including their case selection and treatment planning decisions, with more experienced practitioners tending to use CAT in complex cases.
Methods
This cross-sectional study received approval from the Scientific Research and Publication Ethics Committee of Nuh Naci Yazgan University (Approval No: 2024/002–04). A total of 2,395 registered orthodontists were identified as the target population based on the Turkish Orthodontic Society membership records. Using a 95% confidence level, 5% margin of error, and a response distribution of 50%, the minimum required sample size was calculated to be 331. Accordingly, the final sample size (n = 338) exceeded this threshold, ensuring adequate statistical power and representativeness for the target population.
Based on current literature, an original electronic questionnaire was designed to evaluate clinical protocols, treatment preferences, and orthodontists’ perspectives on CAT. The survey was administered using the Google Forms platform (Google LLC, Mountain View, CA, USA). Google Forms was selected on the basis that it is an effective data collection instrument that facilitates secure, accessible, and anonymous response aggregation. The design and reporting of the questionnaire were guided by the CHERRIES checklist [19].
To ensure clarity and relevance, a single-stage pilot study was conducted with 15 orthodontists who had at least 10 years of CAT experience. Based on their feedback, minor wording and phrasing adjustments were made to improve clarity and clinical relevance. After these revisions, the same group of experts subsequently evaluated each question using a three-point relevance scale (“essential,” “useful but not essential,” and “not necessary”) following Lawshe’s content validity method. Content validity ratios were calculated for each question, and two questions falling below the critical threshold were excluded from the final version of the questionnaire [20]. The final questionnaire included separate sections for CAT providers and non-providers. The average completion time was 10 min.
The final questionnaire comprised 35 questions divided into three sections for orthodontists who use CAT: Sect. 1 gathered demographic information; Sect. 2 focused on the management of CAT, case selection, and treatment protocols; and Sect. 3 addressed patient profiles and their reasons for opting for CAT (Additional file 1). In Sect. 2, a 5-point Likert scale (1 = least important, 5 = most important) was employed to assess factors influencing treatment success, while a 6-point Likert scale (1 = easiest, 6 = most difficult) was used to evaluate the perceived difficulty of various tooth movements. Clinical experience with CAT was assessed based on two criteria: the number of years the orthodontist had been providing CAT and the total number of cases they had completed with CAT. Clinical experience with CAT was assessed using duration of CAT practice (1–2, 2–5, and 5–10 years) and number of completed CAT cases (No case, 1–10, 11–30, > 30). Orthodontists who had treated more cases and had a longer history of using CAT were considered to have higher levels of clinical experience.
For orthodontists who do not use CAT, the questionnaire included 7 specific questions aimed at exploring their reasons for not adopting CAT and their future intentions (Additional file 1).
The online survey was distributed to members of the Turkish Orthodontic Society (TOD), the national association for orthodontic specialists in Türkiye. An initial email containing the survey link was sent to all registered members on February 20, 2024. Upon accessing the link, participants were presented with a brief description outlining the study’s objectives, the voluntary and anonymous nature of participation, and a statement of informed consent. To proceed to the survey, participants were required to check a pre-determined box indicating their consent. Only after confirming their agreement were they directed to the subsequent sections containing demographic questions and the study questionnaire. A reminder email was sent on March 21, 2024, and the survey remained open for one additional week. Data collection was completed on March 28, 2024. Survey responses were exported from Google Forms to Microsoft Excel (Version 2410; Microsoft, Redmond, WA) for data processing and cleaning.
Statistical analysis
Demographic data and responses to survey questions were summarized using frequencies and percentages. Chi-square tests were used to compare groups based on differences in clinical experience. For post hoc analysis in multiple comparisons, Bonferroni-adjusted standardized residuals (z-scores) were applied. Effect sizes for significant chi-square associations were calculated using Cramér’s V to indicate the strength of the relationships. All statistical analyses were performed using SPSS software (Version 22.0; SPSS Inc., Chicago, IL). Questions that allowed the orthodontists to “select all that apply” were analyzed by evaluating each response option individually. A significance level of p < 0.05 was set for determining statistical significance.
Results
Participant characteristics and CAT experience
The survey was distributed to 2,395 active members of the Turkish Orthodontic Society. A total of 338 participants completed the questionnaire, yielding a response rate of 14.1%.
69.5% of respondents actively use CAT. Among them, 44.7% had 1–2 years and an equal proportion had 2–5 years of experience, while 10.6% had used CAT for more than 5 years. Overall, 80.4% of respondents had completed at least one CAT case. Of these, 37% reported completing 1–10 cases, 15.7% completed 11–30 cases, and 27.7% reported more than 30 completed cases, whereas 19.6% had not yet completed any case, (Supplementary Table 1, Additional file 2).
Clinical experience and complexity
More than half of the participants reported achieving desired treatment outcomes without the need for fixed appliances. The most commonly treated malocclusions with CAT were Class I crowding and Class I diastema, (Supplementary Table 1, Additional file 2).
Increased clinical experience—measured by years of use and number of cases— was correlated with broader use of CAT, particularly in complex cases such as extractions, severe crowding, and skeletal Class II/III malocclusions, (p < 0.001, Cramer’s V = 0.302–0.400.302.400), (Tables 1 and 2, Supplementary Table 1, Additional file 3). More experienced orthodontists were more comfortable treating challenging cases and more likely to use adjunctive mechanics (p < 0.001, Cramer’s V = 0.385–0.443), (Table 3, Supplementary Table 1, Additional file 3). Less experienced orthodontists tended to avoid orthognathic surgery cases, whereas more experienced ones avoided short clinical crowns, (Supplementary Table 1, Additional file 3).
Table 1.
CAT use for extraction cases by clinical experience
| Years providing CAT | Do you use CAT of extraction cases? | ||
|---|---|---|---|
| Yes | No | ||
| 1–2 years | 36 (34.3)a | 69 (65.7)a | |
| 2–5 years | 68 (64.8)b | 37 (35.2)b | |
| 5–10 years | 16 (64.0)b | 9 (36.0)b | |
| χ2 | 21.387 | ||
| p value | < 0.001* | ||
| Cramer’s V | 0.302 | ||
| Number of cases completed with CAT | Yes | No | |
| No cases | 7(15.2)a | 39(84.8)a | |
| 1–10 cases | 44(50.6)b | 43(49.4)b | |
| 11–30 cases | 40(61.5)bc | 25(38.5)bc | |
| 30 + | 29(78.4)c | 8(21.6)c | |
| χ2 | 37.563 | ||
| p value | < 0.001* | ||
| Cramer’s V | 0.400 | ||
* p value from chi-squared tests
a−c No difference between interactions with the same letter
Table 2.
Preferred crowding severity and malocclusion types managed with CAT according to clinical experience
| How many millimeters of crowding do you treat with CAT? | 1–2 years | 2–5 years | 5–10 years | χ2 | p value | No cases | 1–10 cases | 11–30 cases | 30 + | χ2 | p value |
|---|---|---|---|---|---|---|---|---|---|---|---|
| n (%) | n (%) | n (%) | n (%) | n (%) | n (%) | n (%) | |||||
| 1–4 mm | 74 (70.5)a | 50 (47.6)b | 9 (36.0)b | 45.640 | < 0.001* | 36(78.3)a | 49(56.3)ab | 22(59.5)ab | 26(40.0)b | 96.872 | < 0.001* |
| 4–8 mm | 73 (69.5)a | 88 (83.8)b | 20 (80.0)a, b | 18(39.1)a | 72(82.8)b | 37(100)c | 54(83.1)b | ||||
| 8–10 mm | 33 (31.4)a | 45 (42.9)a | 8 (32.0)a | 12(26.1)a | 30(34.5)a | 15(40.5)a | 29(44.6)a | ||||
| 10 mm + | 10 (9.5)a | 23 (21.9)b | 12 (48.0)c | 5(5.7)a | 6(13)ab | 11(29.7)bc | 23(35.4)c | ||||
| Cramer’s V 0.158 | Cramer’s V 0.154 | ||||||||||
| Class I spacing | 69 (65.7)a | 77 (73.3)a | 21 (84.0)a | 141.529 | < 0.001* | 26(56.5)a | 59(67.8)ab | 27(73)ab | 55(84.6)b | 202.934 | < 0.001* |
| Class I crowding | 103 (98.1)a | 103 (98.1)a | 21 (84.0)a | 44(95.7)a | 85(97.7)a | 37(100)a | 61(93.8)a | ||||
| Class I deep bite | 51 (48.6)a | 77 (73.3)b | 21 (84.0)b | 19(41.3)a | 54(62.1)ab | 24(64.9)ab | 52(80.0)b | ||||
| Class I open bite | 59 (56.2)a | 74 (70.5)a, b | 21 (84.0)b | 19(41.3)a | 51(58.6)a | 31(83.8)b | 53(81.5)b | ||||
| Class II deep bite | 40 (38.1)a | 78 (74.3)b | 19 (76.0)b | 15(32.6)a | 44(50.6)a | 29(78.4)b | 49(75.4)b | ||||
| Class II open bite | 43 (41.0)a | 69 (65.7)b | 17 (68.0)b | 20(43.5)a | 31(35.6)a | 33(89.2)b | 45(69.2)b | ||||
| Class III deep bite | 15 (14.3)a | 43 (41.0)b | 16 (64.0)b | 7(15.2)a | 11(12.6)a | 20(54.1)b | 36(55.4)b | ||||
| Class III open bite | 19 (18.1)a | 41 (39.0)b | 14 (56.0)b | 6(13)a | 17(19.5)a | 22(59.5)b | 29(45.3)b | ||||
| Cramer’s V 0.115 | Cramer’s V 0.116 | ||||||||||
The left part of the table shows how many years orthodontists have been providing CAT. The right part shows the number of CAT cases they have completed
* p value from chi-squared tests
a−c No difference between interactions with the same letter
Table 3.
Use of auxiliary techniques in CAT by clinical experience
| Use of auxiliary techniques | 1–2 years | 2–5 years | 5–10 years | χ2 | p value | No cases | 1–10 cases | 11–30 cases | 30 + | χ2 | p value |
|---|---|---|---|---|---|---|---|---|---|---|---|
| n (%) | n (%) | n (%) | n (%) | n (%) | n (%) | n (%) | |||||
| Yes | 83 (79.0)a | 105 (100.0)b | 25 (100.0)b | 30.051 | < 0.001* | 30 (65.2)a | 81 (93.1)b | 37 (100.0)b | 65 (100.0)b | 46.191 | < 0.001* |
| No | 22 (21.0)a | 0 (0.0)b | 0 (0.0)b | 16 (34.8)a | 6 (6.9)b | 0 (0.0)b | 0 (0.0)b | ||||
| Cramer’s V 0.385 | Cramer’s V 0.443 | ||||||||||
The left part of the table shows how many years orthodontists have been providing CAT. The right part shows the number of CAT cases they have completed
* p value from chi-squared tests
a−b No difference between interactions with the same letter
Distalization was reported to be more effectively achieved with CAT than with fixed appliances. In addition, CAT was perceived to be superior for intrusion and expansion. However, no statistically significant association was found between the perceived superiority of specific tooth movements and CAT experience (p = 0.153; p = 0.061), (Table 4).
Table 4.
Perceived advantages of clear aligners over fixed appliances by clinical experience
| In which of the following tooth movements do you believe clear aligners are superior to fixed orthodontic appliances? | 1–2 years | 2–5 years | 5–10 years | χ2 | p value | No cases | 1–10 cases | 11–30 cases | 30 + | χ2 | p value |
|---|---|---|---|---|---|---|---|---|---|---|---|
| n (%) | n (%) | n (%) | n (%) | n (%) | n (%) | n (%) | |||||
| Distalization | 89 (84.8) | 77 (73.3) | 20 (80.0) | 21.696 | 0.153 | 37(80.4) | 64(73.6) | 30(81.1) | 55(84.6) | 37.795 | 0.061 |
| Mesialization | 5 (4.8) | 2 (1.9) | 1 (4.0) | 1(2.2) | 5(5.7) | 0(0) | 2(3.1) | ||||
| Rotation | 6 (5.7) | 3 (2.9) | 0 (0.0) | 0(0) | 6(6.9) | 2(5.4) | 1(1.5) | ||||
| Intrusion | 34 (32.4) | 54 (51.4) | 11 (44.0) | 12(26.1) | 34(39.1) | 26(70.3) | 27(41.5) | ||||
| Extrusion | 5 (4.8) | 8 (7.6) | 1 (4.0) | 0(0) | 6(6.9) | 3(5.7) | 1(1.5) | ||||
| Expansion | 21 (20.0) | 29 (27.6) | 7 (28.0) | 12(26.1) | 11(12.6) | 14(37.8) | 20(30.8) | ||||
| Root movement | 2 (1.9) | 4 (3.8) | 1 (4.0) | 1(2.2) | 3(3.4) | 1(2.7) | 2(3.1) | ||||
| None of the above | 9 (8.6) | 14 (13.3) | 1 (4.0) | 5(10.9) | 10(11.5) | 2(5.4) | 7(10.8) | ||||
| Cramer’s V 0.127 | Cramer’s V 0.155 | ||||||||||
The left part of the table shows how many years orthodontists have been providing CAT. The right part shows the number of CAT cases they have completed
* p value from chi-squared tests
Root movement was rated as the most difficult (3.88 ± 1.59), while tipping was the easiest (2.46 ± 1.93). By experience level, rotation was rated most difficult by those with 1–2 years, root movement by those with 2–5 years, and extrusion by those with 5–10 years. All groups agreed tipping was the easiest movement (Fig. 1). Patient cooperation (4.42 ± 0.81) was consistently rated as the most critical success factor, whereas aligner brand (3.54 ± 1.14) was the least (Fig. 2). With more experience, orthodontists expertise was valued over case selection.
Fig. 1.
Perceived difficulty of tooth movements with CAT by clinical experience and number of cases completed
Fig. 2.
Perceived factors affecting CAT success by clinical experience and number of cases completed
Patients were generally satisfied with CAT outcomes but satisfaction levels varied significantly according to orthodontists’ experience, both in terms of years providing CAT and the number of completed cases (p = 0.021 and p < 0.001, Cramer’s V = 0.222–0.361), (Table 5).
Table 5.
Patient satisfaction according to clinical experience
| Patient satisfaction | 1–2 years | 2–5 years | 5–10 years | χ2 | p value | No cases | 1–10 cases | 11–30 cases | 30 + | χ2 | p value |
|---|---|---|---|---|---|---|---|---|---|---|---|
| n (%) | n (%) | n (%) | n (%) | n (%) | n (%) | n (%) | |||||
| Always/All the time | 8 (9.1)a | 25 (23.4)b | 11 (27.5)b | 11.571 | 0.021* | 2(4.3)a | 8(9.2)a | 15(40.5)b | 19(29.2)b | 30.639 | < 0.001* |
| Mostly/Most of the time | 80 (90.9)a | 80 (74.8)b | 29 (72.5)b | 44(95.7)a | 78(89.7)a | 21(56.8)b | 46(70.8)b | ||||
| Sometimes | 0 (0.0)a | 2 (1.9)a | 0 (0.0)a | 0 (0.0)a | 1 (1.1)a | 1 (2.7)a | 0 (0.0)a | ||||
| Cramer’s V 0.222 | Cramer’s V 0.361 | ||||||||||
The left part of the table shows how many years orthodontists have been providing CAT. The right part shows the number of CAT cases they have completed
* p value from chi-squared tests
a−b No difference between interactions with the same letter
Refinement procedures became significantly more frequent as orthodontists gained experience and completed a greater number of cases (Table 6). Less experienced orthodontists reported using refinements rarely, whereas more experienced orthodontists applied them routinely (p < 0.001, Cramer’s V = 0.413–0.322), (Table 6).
Table 6.
Use of refinements in CAT by clinical experience
| Use of refinements | 1–2 years | 2–5 years | 5–10 years | χ2 | p value | No cases | 1–10 cases | 11–30 cases | 30 + | χ2 | p value |
|---|---|---|---|---|---|---|---|---|---|---|---|
| n (%) | n (%) | n (%) | n (%) | n (%) | n (%) | n (%) | |||||
| 10% or less | 37 (35.2)a | 3 (2.9)b | 1 (4.0)b | 79.985 | < 0.001* | 23 (50.0)a | 14 (16.1)b | 1 (2.7)b | 3 (4.6)b | 73.167 | < 0.001* |
| 25% | 11 (10.5)a | 21 (20.0)a, b | 10 (40.0)b | 6 (13.0)a | 15 (17.2)a | 3 (8.1)a | 18 (27.7)a | ||||
| 50% | 29 (27.6)a | 26 (24.8)a, b | 1 (4.0)b | 6 (13.0)a | 31 (35.6)b | 12 (32.4)b | 7 (10.8)c | ||||
| 75% | 17 (16.2)a | 47 (44.8)b | 4 (16.0)a | 6 (13.0)a | 17 (19.5)a | 17 (45.9)b | 28 (43.1)b | ||||
| 100% | 11 (10.5)a | 8 (7.6)a | 9 (36.0)b | 5 (10.9)a | 10 (11.5)a | 4 (10.8)a | 9 (13.8)a | ||||
| Cramer’s V 0.413 | Cramer’s V 0.322 | ||||||||||
The left part of the table shows how many years orthodontists have been providing CAT. The right part shows the number of CAT cases they have complete
* p value from chi-squared tests
a−b No difference between interactions with the same letter
Orthodontists with greater experience were less likely to believe that CAT provides superior or faster outcomes than fixed appliances, viewing both as comparable (p = 0.005–0.001) (Supplementary Tables 2–3, Additional file 3).
Non-providers responses
Among non-providers, 44.7% were affiliated with university hospitals. Although 80.6% were not using CAT at the time, most intended to adopt it in the future. The main barrier was lack of equipment, (Supplementary Table 2, Additional file 2).
Discussion
In our study, clinical experience emerged as a key factor influencing treatment preferences. Consistent with previous research, the absence of standardized criteria for defining CAT expertise led to the adoption of a pragmatic, experience-based classification [17, 21, 22]. Clinical experience was significantly associated with the frequency of CAT use, particularly in complex cases such as extractions and skeletal malocclusions. The greater use of CAT by experienced orthodontists likely reflects their ability to manage space closure and biomechanical challenges more effectively. Previous studies have also reported that premolar extraction cases are rarely treated with CAT due to their inherent complexity, with clinicians often opting for non-extraction approaches supported by mandibular incisor extraction or auxiliary mechanics [3, 11, 15, 17]. These findings highlight that managing extraction cases with CAT remains clinically demanding.
Consistent with previous studies, CAT is most commonly preferred for Class I mild-to-moderate crowding and diastema cases, whereas its application in complex situations such as severe crowding, skeletal malocclusions, impacted teeth, and orthognathic surgery remains limited [3, 11, 16–18]. Miranda et al. and Abu-Arqub et al. reported that only 30–40% of orthodontists felt confident managing such complex cases with CAT, indicating widespread hesitancy [3, 17]. This study addresses a gap in the literature by demonstrating that orthodontists who reported higher confidence were those with greater clinical experience, using CAT more frequently and confidently in complex cases. Conversely, Best et al. found that general dentists were more likely to attempt complex treatments, suggesting that limited knowledge may lead to inappropriate case selection and lower predictability [18]. In contrast, our results show that increasing experience promotes more deliberate and controlled management of complex cases, likely because all participants in this study were orthodontic specialists and less experienced orthodontists may be more aware of their own limitations.
The thermoforming process and intraoral use of thermoplastic materials can alter their mechanical properties and affect force delivery [17]. Such changes may lead to less predictable force systems than those of fixed appliances, making the effective use of attachments, auxiliaries, and advanced biomechanics critical for success in complex cases [17, 23]. The more frequent use of auxiliaries among experienced orthodontists likely reflects their deeper biomechanical understanding and confidence in complex case management. This finding is consistent with Best et al., who reported that general dentists with limited biomechanical understanding used auxiliaries less systematically [18]. Overall, clinical experience appears to enhance not only the frequency but also the quality of auxiliary use in accordance with biomechanical principles.
The perception of tipping as the easiest and root movement as the most difficult tooth movement aligns with previous reports indicating that forces applied farther from the center of resistance favor tipping, whereas root movement requires precise force control [17, 23, 24]. Participants rated distalization as the most predictable, intrusion moderately effective, and torque, mesialization, rotation, and especially extrusion as the least controllable, reflecting the biomechanical limitations of CAT. The limited force transmission of thermoplastic materials increases tipping tendencies and reduces torque efficiency; even with ellipsoid attachments, torque beyond 5° remains less than 50% effective [25, 26]. Overall, distalization appears predictable with standard protocols, whereas expansion, root movement, and especially extrusion require greater clinical experience. These findings are consistent with previous reports describing distalization as the most predictable and mesialization and rotation as less controllable [24–29]. Even experienced orthodontists considered extrusion unpredictable, reinforcing its well-documented difficulty in CAT [6, 23, 24, 30].
Patient cooperation and clinician experience were the most influential factors for treatment success, whereas brand selection had the least impact. This pattern suggests that the quality of digital planning, case suitability, patient compliance, and clinical skill play far greater roles than the specific aligner brand used. These results align with previous reports emphasizing that marketing factors exert little impact on clinical outcomes [3, 11]. Moreover, the tendency of experienced orthodontists to attribute success more to their expertise than to case selection implies that, with growing experience, orthodontists increasingly rely on their biomechanical understanding and clinical judgment.
The frequency of refinements was significantly associated with clinical experience. Less experienced orthodontists reported using refinements occasionally, whereas experienced orthodontists applied them routinely, reflecting greater biomechanical awareness and clinical maturity rather than treatment failure. This may also relate to their higher involvement in complex cases. Refinement serves not only as a technical adjustment but as a strategic approach for stepwise management of difficult cases. Similarly, Miranda et al. reported more frequent digital plan revisions with experience, while Abu-Arqub et al. and Maurice et al. found refinement stages to be almost inevitable in most cases [3, 11, 17]. Kravitz et al. observed that only 6% of patients required no refinements, a rate higher in older patients [12].
Perceptions of CAT’s advantages over fixed appliances appear to differ according to clinical experience. Experienced orthodontists viewed this belief more critically, whereas less experienced orthodontists more often reported that CAT shorten treatment time. This may stem from CAT being introduced mainly through simple cases in training and from limited exposure of novices to complex cases. Furthermore, an excessive reliance on digital setups has the potential to create the impression of accelerated treatment. With experience, orthodontists better recognize biomechanical complexity and the need for refinements, forming a more realistic understanding of treatment duration. Previous studies similarly reported that mild cases can be completed faster with CAT, while complex malocclusions yield more predictable outcomes with fixed appliances [3, 9, 11, 15, 17]. Lin et al. found that simple cases treated with fixed appliances finished about 4.8 months earlier on average [9]. As clinicians gain experience, their perception of treatment efficiency becomes more balanced and grounded in realistic expectations.
Participants did not currently use CAT, though most planned to adopt it in the future, indicating growing acceptance. Conversely, the discontinuation by some orthodontists indicates that limited technical infrastructure and insufficient training remain key barriers. This may reflect not the shortcomings of CAT, but rather the younger age, limited experience, and local practice constraints of the respondents [3, 11, 16]. Enhancing technical resources and expanding clinical training could therefore promote wider and more effective adoption of CAT in routine practice.
To date, no study has comprehensively examined orthodontists’ attitudes toward CAT in relation to their clinical experience. By identifying measurable indicators such as the duration of CAT use and the number of completed cases, this study provides new insight into how experience shapes treatment preferences and decision-making. The findings highlight the decisive role of clinical experience in treatment planning and support the notion that growing expertise fosters more informed and confident use of CAT, thereby offering a valuable framework for future research.
This study has several limitations. As a cross-sectional survey, it reflects participants’ views at a single time point and may not capture changes in clinical practice or opinion over time. The use of a specific sample may also limit the generalizability of the findings, particularly across different regions. The relatively low response rate could have introduced response bias, potentially influenced by survey length or the lack of participation incentives. In addition, reliance on self-reported data may have led to recall bias or subjective interpretation, limiting how accurately real clinical practices and outcomes are represented. Finally, as most respondents had moderate experience levels, early-career and highly experienced orthodontists may have been underrepresented. Future longitudinal studies with larger and more diverse samples are warranted to validate these results.
Conclusions
Clinical experience significantly influences orthodontists’ approaches to CAT.
More experienced orthodontists tended to employ CAT in complex cases, such as those involving extractions or severe malocclusions, and to integrate adjunctive mechanics—such as attachments and auxiliaries— more effectively and confidently.
Patient compliance was identified as the most critical factor for treatment success, while aligner brand had minimal impact.
These findings underscore the pivotal role of clinical experience in CAT practice and support the need for structured, experience-based training to prepare less experienced orthodontists for increasingly complex CAT.
The integration of targeted aligner-focused training modules, case-based learning, and continuing education programs has the potential to facilitate skill development and enhance clinical decision-making among less experienced orthodontists.
Supplementary Information
Additional file 1: Original questionnaire items used in the CAT survey.
Additional file 2: Frequency distributions of responses from CAT providers and non-providers.
Additional file 3: Supplementary Tables: Perceived advantages, treatment efficacy, and treatment time of clear aligners based on clinical experience.
Acknowledgements
The authors would like to express their gratitude to Assist. Prof. Dr. Osman Demir for his invaluable assistance during statistical analysis. The authors would like to express their sincere gratitude to Dr. Ludovica Nucci for her valuable guidance, constructive feedback, and continuous support throughout the revision process of this manuscript.
Abbreviations
- CAT
Clear Aligner Therapy
Authors’ contributions
H.D contributed to conceptualization, data curation, methodology, investigation, formal analysis, validation, visualization, manuscript review and editing, and original draft preparation; M.A contributed to conceptualization, investigation, formal analysis, original draft preparation and manuscript review and editing; and L.P contributed to manuscript editing.
Funding
The author(s) received no financial support for the research.
Data availability
Available upon reasonable request and after approval of all authors.
Declarations
Ethics approval and consent to participate
Prior to participation, all subjects provided electronic informed consent, ensuring their anonymity and the confidentiality of their information. All study procedures were conducted in accordance with the ethical standards outlined in the Declaration of Helsinki. This cross-sectional study received approval from the Scientific Research and Publication Ethics Committee of Nuh Naci Yazgan University (Approval No: 2024/002–04).
Consent for publication
Not applicable.
Competing interests
The authors declare no competing interests.
Footnotes
Publisher’s Note
Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.
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Associated Data
This section collects any data citations, data availability statements, or supplementary materials included in this article.
Supplementary Materials
Additional file 1: Original questionnaire items used in the CAT survey.
Additional file 2: Frequency distributions of responses from CAT providers and non-providers.
Additional file 3: Supplementary Tables: Perceived advantages, treatment efficacy, and treatment time of clear aligners based on clinical experience.
Data Availability Statement
Available upon reasonable request and after approval of all authors.