Dentistry

Cite as: Archiv EuroMedica. 2026. 16; 5. DOI 10.35630/2026/16/Iss.5.25

Received 15 July 2026;
Accepted 25 October 2026;
Published 27 October 2026

COMPLICATIONS AND FAILURE RATES OF TEMPORARY ANCHORAGE DEVICES IN ORTHODONTICS: A SCOPING REVIEW

Tomasz Horodniczy¹ , Justyna Polko² ,
Zuzanna Jeziorska² , Izabela Migdał² ,
Bartosz Szymajda² , Maja Witek³ ,
Zuzanna Galicka² , Jakub Artur Czapkiewicz² ,
Weronika Kwaśnica⁴ , Katarzyna Raczek⁵

¹ Ortho.pl Dental Office, Wrocław, Poland
² Medical University of Silesia, Katowice, Poland
³ Medical University of Warsaw, Warsaw, Poland
⁴ Poznan University of Medical Sciences, Poznan, Poland
⁵ Wroclaw Medical University, Wroclaw, Poland

download article (pdf)

  polkojustyna95@gmail.com

ABSTRACT

Background

Temporary anchorage devices (TADs) provide skeletal anchorage in orthodontics, but reported complications and success and failure rates vary across studies.

Aim

To summarize evidence on TAD complications, success and failure rates, and factors investigated in relation to these outcomes.

Methods

PubMed, Europe PMC and BASE were searched on 20 August 2026. Eligibility was restricted to English publications with freely accessible full texts. Two reviewers independently selected studies and extracted data. Thirty-seven studies were included and synthesized descriptively without meta-analysis.

Results

Outcomes varied across device types, anatomical sites, loading protocols and follow-up periods. Failures frequently occurred during the first few months after insertion. Root contact was associated with failure in several studies, and peri-implant inflammation was associated with early instability in one prospective study. Postoperative pain and sinus penetration were also reported. Findings concerning screw dimensions, insertion procedures, loading time and patient characteristics were inconsistent or specific to particular settings. Greater primary stability did not necessarily correspond to better clinical survival. The predictive value of inflammatory and microbiological findings remained uncertain. Differences in outcome definitions and incomplete reporting limited comparisons.

Conclusions

The available evidence does not support a single protocol for TAD selection, placement or loading. Future prospective studies should distinguish primary stability from clinical success throughout orthodontic loading and use standardized outcome definitions and reporting methods.

Keywords: temporary anchorage devices; orthodontics; complications; failure rates; anchorage stability; scoping review.

INTRODUCTION

Temporary anchorage devices (TADs), including orthodontic mini-implants, micro-implants, palatal implants and miniplates, are widely used in contemporary orthodontics to provide skeletal anchorage and support the control of complex tooth movements. Their clinical value has been supported by generally high reported success and survival rates, often reaching or exceeding 90% in several reviews, although these outcomes vary depending on the type of device, placement site, patient characteristics and orthodontic protocol [20, 19].

Despite their established role in orthodontic treatment, TADs may be associated with complications or failure events, such as reduced stability, loosening or loss of the device, soft-tissue inflammation, discomfort, mucosal overgrowth, or injury to adjacent anatomical structures. Previous reviews have contributed substantially to the understanding of TAD effectiveness and survival; however, they have also highlighted important areas requiring further clarification. In particular, the evidence base is characterized by heterogeneity in study design, terminology, outcome definitions and clinical protocols, which makes direct comparison between studies challenging [20]. Similarly, differences between device types have been reported, with palatal implants and miniplates showing high survival rates and miniscrews demonstrating more variable outcomes, suggesting that device-related and clinical-context factors remain relevant when interpreting success and failure rates [19].

Several potential risk factors for TAD success or failure have been described in the literature and may be grouped into patient-related, device-related, procedure-related and orthodontic treatment-related factors [20]. However, the strength of evidence for specific factors remains uneven. For example, insertion torque has been frequently discussed as a clinically relevant parameter, but existing evidence does not clearly support a specific torque range as being associated with higher success rates. This uncertainty has been attributed to limitations such as subjective definitions of success, variability in measurement methods, and the need for more objective and standardized stability assessments [21].

The present review therefore focuses on a descriptive synthesis of reported complications, success and failure rates, and factors associated with TAD outcomes across different clinical settings.

A scoping review was chosen to summarize evidence from studies with different designs, clinical settings and outcome measures.

AIM AND OBJECTIVES

The aim of this review was to summarize the available evidence on complications and success and failure rates of TADs used in orthodontic treatment.

The specific objectives were to:

1. Describe the complications and adverse events reported in the included studies.
2. Summarize reported success and failure rates in relation to device type, anatomical placement site, loading protocol and follow-up duration.
3. Review the patient, device, anatomical and procedural factors investigated in relation to TAD complications or failure, highlighting inconsistent findings.

METHODS

Eligibility criteria

The population of interest was human patients of any age (children, adolescents, and adults) undergoing orthodontic treatment in which temporary anchorage devices (TADs), including orthodontic mini-implants and micro-implants, were used as skeletal anchorage. Studies conducted on animals or in vitro were excluded. Studies in which mini-implants were used exclusively for non-orthodontic purposes (e.g., purely surgical or prosthetic applications without an orthodontic anchorage role) were also excluded.

The main concept of the review was complications and failure or success rates associated with TADs in orthodontics. Eligible studies were required to report clinical outcomes related to adverse events and/or device stability, such as loss of stability, loosening or loss of the implant, soft tissue inflammation or infection, pain or discomfort, damage to adjacent anatomical structures, and overall success or failure rates. Studies that focused exclusively on biomechanical effectiveness or tooth movement outcomes without any data on complications or failure/success rates were excluded, as were purely technical or narrative articles that did not present clinical data.

The context comprised orthodontic treatment carried out in any clinical setting, including private practices, university clinics, and hospital departments, and in any anatomical location of TAD placement (maxilla, mandible, palate, etc.). Reports describing the use of similar devices solely in non-orthodontic contexts were not considered.

Regarding the types of evidence sources, the review included primary clinical studies such as randomized and non-randomized clinical trials, prospective and retrospective cohort studies, case-control studies, and larger case series (involving at least 8 patients or 20 TADs; the minimum sample-size threshold was defined before screening and applied consistently during study selection). Systematic reviews and other secondary studies were used to identify additional primary studies and to map existing evidence, but they were not considered the primary unit of analysis. Single case reports, very small case series, editorials, letters, and conference abstracts without sufficient clinical data or without an accessible full text were excluded.

Only articles published in English were considered. No lower date limit was applied; studies published up to and including 20 August 2026 were eligible. Furthermore, only studies with freely accessible full-text articles (open access or otherwise available without a paywall) were included in the review. The eligibility criteria are summarized in Table 1.

Information sources

The primary information sources for this scoping review were electronic bibliographic databases. A systematic search was conducted in PubMed (MEDLINE), Europe PMC and Bielefeld Academic Search Engine (BASE) to identify relevant clinical studies reporting complications and/or failure or success rates of temporary anchorage devices used in orthodontics. In addition, the reference lists of included articles and relevant reviews were screened to identify any further eligible studies that were not retrieved by the electronic database searches. Only studies with freely accessible full texts in English were considered.

Search

A structured electronic search was conducted in PubMed (MEDLINE), Europe PMC, and the Bielefeld Academic Search Engine (BASE) using a universal query combining free-text terms related to temporary anchorage devices in orthodontics and their complications or failure/success outcomes. The same universal query was applied across all databases:

("temporary anchorage device" OR "temporary anchorage devices" OR "orthodontic mini implant" OR "orthodontic mini implants" OR miniscrew OR "mini screw" OR "micro implant" OR "skeletal anchorage" OR TAD) AND orthodontic AND (failure OR complication OR infection OR "success rate" OR "survival rate" OR stability OR loosening OR dislodgement OR "root contact" OR "peri-implant inflammation" OR "peri implant inflammation" OR "loading protocol" OR "CBCT planning")

The electronic searches of PubMed, Europe PMC, and BASE were conducted on 20 August 2026.

Selection of sources

All records identified through the database search were imported into the Rayyan screening software, and duplicates were removed (T.H.). The remaining records were screened in two stages using Rayyan, a web-based systematic review management platform. Before formal screening, the reviewers completed a calibration exercise to ensure consistent application of the eligibility criteria. First, titles and abstracts were independently reviewed in a blinded manner to identify potentially relevant studies (K.R. and W.K.). Subsequently, the full texts of the selected articles were independently assessed for eligibility against the predefined inclusion and exclusion criteria (K.R. and W.K.). Any disagreements were resolved through discussion and consensus. Reasons for exclusion at the full-text stage were recorded. The study selection process was presented in a PRISMA-ScR flow diagram (Figure 1).

Data charting process

Data from the included studies were charted using a standardized data charting form developed by the research team. The form was pilot tested on a small sample of studies and refined as necessary. Two reviewers independently charted data from the selected articles using tables prepared in Google Sheets to ensure accuracy and consistency (K.R. and W.K.). Any discrepancies were resolved through discussion and consensus between the reviewers.

Data items

The following data items were collected from each included study when reported: (1) general study characteristics (first author, year of publication, country, study design, clinical setting, study period); (2) population characteristics (number of participants and/or number of TADs, age, sex distribution, relevant patient‑related factors such as oral hygiene, smoking status or systemic conditions, where available); (3) details of the temporary anchorage devices and their use (type of device, dimensions, manufacturer if reported, number of devices per patient, anatomical placement site, side/jaw, indication for use, loading protocol and timing, duration of use, operator characteristics); (4) outcomes related to complications and adverse events (type and number of events such as loss of stability, loosening, complete loss of the device, soft‑tissue inflammation or infection, mucosal overgrowth, pain or discomfort, damage to adjacent roots or other anatomical structures, and any other local or systemic complications); (5) outcomes related to success and failure (definitions of success/failure adopted in the study, number and proportion of successful and failed TADs, timing of failure, reported success or survival rates per device and/or per patient, follow‑up duration); (6) factors examined as potential determinants of complications or failure/success (patient‑, device‑ and procedure‑related variables, including results of any statistical analyses, if reported); and (7) other relevant methodological or reporting details (e.g. inclusion/exclusion criteria, method of outcome assessment, handling of missing data, funding or conflict‑of‑interest statements).

Synthesis of results

The results were synthesized descriptively in line with the scoping review methodology. Extracted data were first organized in tabular form to provide an overview of study characteristics, populations, TAD types and placement sites, as well as reported complications and success/failure outcomes. Studies were then grouped and compared according to key dimensions such as study design, anatomical location, type of device, clinical indication and patient population, where feasible. Frequencies and ranges of reported complications and success/failure rates were summarized narratively, and simple descriptive statistics (e.g. counts, proportions and ranges) were used where appropriate. Particular attention was paid to how success, failure and specific complications are defined and measured across studies, as well as to any reported associations with patient-, device- or procedure-related factors. No formal meta-analysis or quantitative pooling of data was performed, as the primary aim was to map and describe the breadth and nature of the existing evidence rather than to estimate pooled effect sizes.

RESULTS

Selection of sources of evidence

The electronic searches in PubMed, Europe PMC, and the Bielefeld Academic Search Engine (BASE) yielded a total of 1464 records. After the removal of 582 duplicates, 882 records remained for screening. Titles and abstracts were screened against the eligibility criteria, resulting in the exclusion of 836 clearly irrelevant records (e.g., animal or in vitro studies, non-orthodontic use of mini-implants, non-clinical articles, non-English publications, and studies without accessible full text). The full texts of 46 potentially relevant articles were then assessed in detail, of which 37 met all inclusion criteria and were included in the scoping review. The remaining 9 full-text articles were excluded for predefined reasons (e.g., absence of data on complications or failure/success rates, sample size below the threshold for inclusion, conference abstract only, case report, or very small case series) and were listed in Table 2 with the specific reason for exclusion. The study selection process, including the number of records at each stage and the reasons for exclusion at the full-text level, was presented in a PRISMA-ScR flow diagram. Screening of the reference lists of included studies and relevant reviews identified no additional eligible studies.

Characteristics and main findings of included studies

The included studies span randomized trials, prospective and retrospective cohorts, and a case–control design, conducted in clinical orthodontic settings and covering common TAD types, sizes, and placement sites (buccal alveolar, palatal, extra‑alveolar). They report success/survival, timing of failures, and selected complications, and examine patient-, device-, anatomic-, and procedural risk factors. Detailed study characteristics and outcomes are presented in Table 3.

Synthesis of results

Reported TAD success was 79–90% in buccal alveolar sites [14, 7, 4] and ~90–96% in palatal placements [13, 6], while IZC survival over 6 months was comparable to alveolar sites [11]. However, substantial variation was also reported in other clinical settings: success was 73.7% in the maxillary tuberosity [25], 82.1–84.4% for cylindrical and dual-thread miniscrews [30], 85.1% in a prospective cohort [18], and 87.5% for mandibular buccal-shelf and interradicular miniscrews [22].

Failures clustered early: ≈70–80% occurred within 1–4 months after insertion, with a first-month peak; stability generally consolidated by 12–16 weeks [14, 5, 4]. In contrast, some studies reported later failures, particularly in mandibular buccal sites, whereas all primary failures in one prospective study occurred by day 42 [22, 26]. These findings indicate that the timing of failure may depend on anatomical site, loading protocol, operator experience, and implant design [26, 15, 25].

Root contact was the most consistent independent predictor of failure (OR ≈28) on CBCT, outweighing other factors [8]. A separate CBCT-based study similarly identified root contact as the strongest predictor of failure, with an odds ratio of 13.50; among implants contacting a root, each additional millimetre of contact length approximately doubled the failure risk [24]. Miniscrews positioned centrally between the roots showed substantially higher success than those close to or contacting a root [30].

In one cohort, greater distance from the alveolar crest was associated with lower failure odds, indicating the benefit of denser, thicker bone away from the crest [10]. CBCT-based anatomical studies further indicated that greater cortical bone thickness, adequate insertion depth, and a greater distance from the palatal suture may improve primary stability [23]. In the mandibular buccal shelf, the most favourable site was distal to the second molar, approximately 7 mm from the alveolar crest, with an insertion angle of about 30° [37].

In the palate, smaller pilot holes (60% of screw diameter; e.g., 1.2 mm for 2.0-mm screws) increased primary stability and success, with effective torque bands around 20–30 N·cm [13]. Longer miniscrews (10–12 mm) improved alveolar survival compared with 8–9 mm [7], whereas in IZC, longer length raised primary stability without survival benefit and increased sinus penetration and early pain, supporting shorter screws for safety [11]. Surface treatment enhanced removal torque (secondary stability) but did not clearly reduce failures within limited samples [3]. Similarly, double-threaded miniscrews produced higher insertion and removal torque than single-threaded designs [31], although differences in long-term clinical success between cylindrical and dual-thread miniscrews were not statistically significant [30]. Titanium and stainless-steel miniscrews also demonstrated comparable clinical stability and success, suggesting that implant material alone is not a dominant determinant of outcome [38, 39].

Very early loading (≤1 week) increased failure in alveolar cohorts; after 2–4 weeks, loading effects were inconsistent [5, 7]. Nevertheless, a randomized trial found 100% success with both immediate and delayed loading when implant dimensions, insertion angle, force magnitude, placement site, and hygiene instructions were standardized [33]. Immediate loading was associated with more pain, swelling, speech difficulty, chewing difficulty, mild bleeding, and ulceration, but not with increased implant loss [33].

Associations between vertical skeletal pattern and TAD outcome were inconsistent. [15] reported more early failures at lower FMA values, whereas [8] observed higher FMA values in the failure group on bivariate analysis, with no independent effect in multivariable analysis. [14] also reported an association between vertical skeletal pattern and success. These findings should therefore be regarded as heterogeneous and site-specific rather than as evidence of a uniform effect.

In 467 buccal molar TADs, overall failure was 15.6% and was higher in the mandible, males, and patients aged ≥30 years. Early failure increased as FMA decreased, reaching 19.0% in patients with FMA ≤20° [15]. Low FMA may represent a marker of increased early mechanical risk in some posterior buccal cohorts, although the anatomical and temporal specificity of this association remains uncertain. The potential role of predrilling and torque-controlled insertion in such cases remains to be tested prospectively.

Age and sex were not consistently associated with failure: some studies reported higher failure in males, older patients, or patients aged over 45 years [15, 17], whereas other cohorts found no significant demographic effects [18, 8]. In one large cohort, operator experience was the only significant predictor, with implants placed by less-experienced operators showing approximately fourfold higher odds of failure [25].

Among 121 immediately loaded TADs, overall success was 89.3%. Success was higher in vestibular than palatal sites, although the difference was not statistically significant. In 958 TADs used for maxillary distalization, the failure rate was only 1.5%. Failures were more frequent in palatal sites and in patients older than 45 years. A standardized protocol involving pilot drilling, controlled insertion, and immediate loading may have reduced technical variability [17]. The particularly low failure rate in this cohort suggests that immediate loading may be predictable when placement is performed using a standardized protocol with controlled angulation, pilot drilling, and a defined loading force [17].

In a prospective study of 47 TADs, success was 85.1%. Early mobility occurred in 14.8% of implants, most often during the second week. No significant association was found with age, sex, jaw, placement site, mucosal type, or screw dimensions [18]. Peri-implant inflammation was associated with early instability. During the first week, success decreased from 92.9% without inflammation to 33.3% with moderate inflammation; during the second week, it decreased from 96.3% to 63.6%, respectively [18]. Pain was common shortly after insertion but decreased over time and was not associated with TAD success. Therefore, pain alone should not be considered a predictor of failure [18].

Immediate loading may be successful when placement, force, and case selection are carefully controlled. However, its effects depend on implant design, bone quality, insertion technique, and soft-tissue condition [16, 18]. A randomized trial of low-level diode laser therapy reported lower Periotest values and greater stability at 1 and 3 months, together with reduced IL-1β concentrations, suggesting that modulation of peri-implant inflammation may improve early stability [29]. However, the study assessed stability rather than definitive implant survival and included a small final sample.

Vertical skeletal pattern and other patient-related characteristics correlated with lower success in posterior buccal placements in some analyses [14, 15], but the association was mainly observed during the first 120 days in patients with lower FMA values in the Yoshida cohort [15], whereas the Yamaguchi study reported higher FMA values in the failure group on bivariate analysis, without an independent effect in multivariable analysis [8]. In the prospective study by Omer, age and sex were not significant predictors of success [18].

Site-related soft-tissue context influenced complications: buccal fold showed more mobility/inflammation than palate; intrusion mechanics had higher loosening than extrusion [6]. Keratinized mucosa showed numerically higher success, although mucosal type was not statistically significant [18]. IZC sinus penetration was common radiographically yet usually asymptomatic; deeper penetration may elevate risk [11]. In the IZC trial, sinus penetration occurred in more than half of the implants and was numerically more frequent with 14-mm than 12-mm screws, while longer screws also produced greater pain on the first postoperative day. These findings support choosing the shortest screw that provides adequate mechanical stability [11].

Biological correlates of failure included elevated peri-implant IL-6 [9] and dysbiotic microbiota enriched in periodontal pathogens, notably Prevotella intermedia [1]. Peri-implant inflammation may also serve as an early clinical marker of failure [18]. The microbiome study further showed distinct microbial profiles between failed and successful TADs, with enrichment of Prevotella intermedia, Eikenella corrodens, Parvimonas species, and other periodontal pathogens in failed implants. Prevotella intermedia demonstrated promising discriminatory ability for failure, although these findings remain preliminary [1].

Insertion technique and imaging guidance may also influence the risk of anatomical complications. CBCT-guided placement produced significantly lower vertical deviation than two-dimensional radiography combined with a surgical guide, and root contact occurred only in the radiography group in one randomized study [36]. However, the differences in mesiodistal, transverse, and angular deviations were not statistically significant. A separate randomized study found that a 3D-printed surgical guide produced lower platform deviation than real-time navigation or freehand placement, although no immediate clinical complications were observed [12].

For anterior maxillary intrusion, insertion angle appeared particularly important: 90° placement showed greater six-month stability than 45° placement, although the absolute stability rates were low in both groups. Male patients also demonstrated higher six-month stability than female patients in that study; because of the small sample and high overall failure rate, these findings should be interpreted cautiously [40].

Loading time should therefore be interpreted together with implant design, insertion technique, force magnitude, bone quality, and soft-tissue health [16, 18]. The available evidence also suggests that a healing period may be particularly important in conventional alveolar sites, whereas immediate loading can be acceptable in carefully selected cases with high primary stability [5, 33, 17]. Immediate loading should therefore be regarded as a protocol-dependent clinical option rather than a universally equivalent alternative to delayed loading.

Methodological heterogeneity, nonstandard success/failure definitions, variable follow-up, and incomplete reporting of torque, loading, and tissue conditions limit direct comparison and pooling across studies [14, 7, 8]. Additional limitations arise from the use of surrogate outcomes, such as insertion or removal torque, Periotest values, and radiographic safety criteria, which do not always correspond to long-term clinical survival [31, 29, 28]. Several studies also included small samples, single-centre populations, or multiple implants per patient without fully accounting for clustering. Consequently, the observed associations should be considered hypothesis-generating rather than definitive evidence of causality.

DISCUSSION

Summary of evidence

The included studies suggest that TAD outcomes vary across anatomical sites and treatment protocols. Failures frequently occurred during the first few months after insertion, although their timing differed between studies [4,5,14]. Root contact was associated with failure in several studies [8,24,30]. These findings identify anatomical relationships as an important consideration when interpreting TAD outcomes, but they do not establish a single placement protocol applicable to all sites.

The findings also distinguish initial mechanical stability from longer-term clinical success. Longer screws were associated with better survival in some alveolar sites, whereas greater length in the infrazygomatic crest improved primary stability without a clear survival benefit and was associated with sinus penetration and early pain [7,11]. Similarly, findings on palatal pilot-hole preparation cannot automatically be extended to other anatomical sites [13]. Evidence on loading time was inconsistent: early loading was associated with failure in some cohorts, while a randomized trial reported no failures with either immediate or delayed loading [5,7,33]. These differences limit conclusions about the independent effect of loading time.

Associations with skeletal pattern and demographic characteristics were also inconsistent. Low FMA values were associated with early failure in the Yoshida cohort, whereas the association with higher FMA values in the Yamaguchi study did not remain independent in multivariable analysis [8,15]. Findings on age and sex likewise differed between studies [8,15,17,18]. These variables therefore cannot be treated as uniform predictors of failure across clinical settings.

Biological findings require similarly cautious interpretation. In one prospective study, peri-implant inflammation was associated with early instability, whereas postoperative pain decreased over time and was not associated with success [18]. Differences in inflammatory markers and microbial composition were also reported between successful and failed devices [1,9]. These associations do not establish whether the biological changes preceded instability or developed alongside it, and their value for predicting failure remains uncertain.

Previous reviews provide context for the present findings. Schätzle et al. reported differences in failure rates between TAD types [19], while Ramírez-Ossa et al. identified factors related to the device, patient, procedure and orthodontic treatment that were associated with TAD outcomes [20]. Reynders et al. specifically examined the relationship between insertion torque and mini-implant success and highlighted the need for more objective stability measurements [21].

Strengths

This review considers reported complications alongside TAD success and failure outcomes, bringing together findings on anatomical, mechanical, inflammatory and microbiological factors. The structured presentation of study characteristics, outcome definitions and loading protocols provides context for interpreting differences between studies. Independent screening and data extraction by two reviewers, with disagreements resolved through discussion, were used to reduce errors in study selection and data collection.

Limitations

The search was limited to PubMed, Europe PMC and BASE, and inclusion was restricted to publications in English with freely accessible full texts. Relevant studies available through other sources, in other languages or behind paywalls may therefore have been omitted. The full-text restriction reflected the lack of institutional access to subscription-only articles and may have introduced availability bias.

The included studies differed in design, sample size, anatomical site, device characteristics, loading protocol, follow-up duration and outcome definitions. These differences limited direct comparison of reported success, failure and complication rates. Retrospective designs and small samples in some studies also limit confidence in the reported associations.

Potentially relevant variables, including bone quality, oral hygiene, insertion torque, loading force and soft-tissue condition, were not consistently reported. Some studies assessed mechanical or radiographic measures rather than clinical survival or complications, and these outcomes should not be treated as equivalent. Associations identified in observational studies do not establish causality.

This review provides a descriptive synthesis without pooled estimates of success or failure. Heterogeneity among the included studies and limitations of the available comparisons prevent firm conclusions about the relative performance of different devices, placement techniques or loading protocols.

CONCLUSIONS

Reported TAD success, failure and complication outcomes varied across anatomical sites and treatment protocols. Failures frequently occurred during the first few months after insertion. Root contact was associated with failure in several studies, while peri-implant inflammation was associated with early instability in one prospective study. Postoperative pain and sinus penetration were also reported. The predictive value of inflammatory and microbiological findings remains uncertain.

Findings concerning device dimensions, insertion procedures, loading time and patient characteristics were inconsistent or specific to particular clinical settings. The available evidence does not support a single protocol for TAD selection, placement or loading.

Differences in study design, follow-up duration and outcome definitions, together with incomplete reporting of relevant variables, limited comparisons between studies. Future prospective studies should distinguish primary stability from clinical success throughout the intended period of orthodontic loading and use standardized outcome definitions and reporting methods.

DISCLOSURE

Author Contributions

Conceptualization: Tomasz Horodniczy
Methodology: Tomasz Horodniczy, Justyna Polko, Izabela Migdał
Data collection: Katarzyna Raczek, Weronika Kwaśnica
Analysis: Zuzanna Jeziorska, Bartosz Szymajda
Writing: Jakub Artur Czapkiewicz, Zuzanna Galicka, Maja Witek
Supervision: Tomasz Horodniczy

Ethics Statement

This scoping review was based on previously published studies and did not require ethical approval.

Conflict of Interest

The authors declare no conflicts of interest.

Funding

This research received no external funding.

Use of Artificial Intelligence

Artificial intelligence tools were used to assist with language editing and formatting. The authors take full responsibility for the content of the manuscript.

REFERENCES

1. Zhao N, Zhang Q, Guo Y, Cui S, Tian Y, Zhang Y, et al. Oral microbiome contributes to the failure of orthodontic temporary anchorage devices (TADs). BMC Oral Health. 2023;23(1):22. doi: https://doi.org/10.1186/s12903-023-02715-7.
2. Yao CCJ, Chang HH, Chang JZC, Lai HH, Lu SC, Chen YJ. Revisiting the stability of mini-implants used for orthodontic anchorage. J Formos Med Assoc. 2015;114(11):1122-1128. doi: https://doi.org/10.1016/j.jfma.2014.08.001.
3. Ravi J, Duraisamy S, Rajaram K, Kannan R, Arumugam E. Survival rate and stability of surface-treated and non-surface-treated orthodontic mini-implants: a randomized clinical trial. Dental Press J Orthod. 2023;28(2):e2321345. doi: https://doi.org/10.1590/2177-6709.28.2.e2321345.oar.
4. Umeh OD, Offojebe UL, Isiekwe IG, Utomi I, daCosta O. Survival analysis of temporary anchorage devices: a retrospective analysis in a Nigerian orthodontic patient population. J Orthod Sci. 2023;12:45. doi: https://doi.org/10.4103/jos.jos_10_23.
5. Jeong JW, Kim JW, Lee NK, Kim YK, Lee JH, Kim TW. Analysis of time to failure of orthodontic mini-implants after insertion or loading. J Korean Assoc Oral Maxillofac Surg. 2015;41(5):240-245. doi: https://doi.org/10.5125/jkaoms.2015.41.5.240.
6. Gurdán Z, Szalma J. Evaluation of the success and complication rates of self-drilling orthodontic mini-implants. Niger J Clin Pract. 2018;21(5):546-552. doi: https://doi.org/10.4103/njcp.njcp_105_17.
7. Tsai CC, Chang HP, Pan CY, Chou ST, Tseng YC. A prospective study of factors associated with orthodontic mini-implant survival. J Oral Sci. 2016;58(4):515-21. doi: https://doi.org/10.2334/josnusd.16-0145.
8. Yamaguchi A, Koizumi S, Ikenaka R, Yamaguchi T. Use of cone-beam computed tomography for investigation of factors affecting the failure of temporary anchorage devices. J Oral Sci. 2024;66(4):247-253. doi: https://doi.org/10.2334/josnusd.24-0180.
9. Andrucioli MCD, Matsumoto MAN, Fukada SY, Saraiva MCP, Bergamo AZN, Romano FL, et al. Quantification of pro-inflammatory cytokines and osteoclastogenesis markers in successful and failed orthodontic mini-implants. J Appl Oral Sci. 2019;27:e20180476. doi: https://doi.org/10.1590/1678-7757-2018-0476.
10. Haddad R, Saadeh M. Distance to alveolar crestal bone: a critical factor in the success of orthodontic mini-implants. Prog Orthod. 2019;20(1):19. doi: https://doi.org/10.1186/s40510-019-0273-1.
11. Alsaeedi AF, Alrubayee MA, Sivamurthy G. Evaluation of Two Mini-implant Lengths in the Infrazygomatic Crest Region: A Randomized Clinical Trial. Eur J Dent. 2025;19(2):399–408. doi: https://doi.org/10.1055/s-0044-1789015.
12. Chen YC, Lin HY, Kok SH, Chang HH, Lin CP. Accuracy and safety of real-time navigation during insertion of temporary anchorage devices - A randomized clinical trial. J Dent Sci. 2025;20(2):1168-1174. doi: https://doi.org/10.1016/j.jds.2025.01.026.
13. Uchida Y, Namura Y, Inaba M, Osada A, Charleston-Coad T, Nakamura Y, et al. Influence of pre-drilling diameter on the stability of orthodontic anchoring screws in the mid-palatal area. J Oral Sci. 2021;63(3):270-274. doi: https://doi.org/10.2334/josnusd.21-0012.
14. Moon CH, Park HK, Nam JS, Im JS, Baek SH. Relationship between vertical skeletal pattern and success rate of orthodontic mini-implants. Am J Orthod Dentofacial Orthop. 2010;138(1):51-57. doi: https://doi.org/10.1016/j.ajodo.2008.08.032.
15. Yoshida M, Nakano H, Haga S, Arishima T, Maki K. Investigation of the association between vertical skeletal patterns and the timing of failure of temporary anchorage devices. Showa Univ J Med Sci. 2022;34(4):191-199. doi: https://doi.org/10.15369/sujms.34.191.
16. Martha K, Pop SI, Farczadi L, Pop RV, Dudás C, Jánosi KM. Success rate of immediately loaded orthodontic temporary anchorage devices: a retrospective analysis of patient- and treatment-related factors. Bioengineering (Basel). 2026;13(7):790. doi: https://doi.org/10.3390/bioengineering13070790.
17. Bettenhäuser-Hartung L, Beyling F, Schwestka-Polly R, Katsaros C, Schmid JQ. Failure rates of 958 interradicular mini-screws for maxillary total arch distalization following a well-established insertion protocol. Eur J Orthod. 2026;48(4):cjag051. doi: https://doi.org/10.1093/ejo/cjag051.
18. Omer ZQ. Prospective study of oral health, pain and discomfort and success rates following insertion of orthodontic mini-implants. Sulaimani Dent J. 2018;5(1):38-48. doi: https://doi.org/10.17656/sdj.10075.
19. Schätzle M, Männchen R, Zwahlen M, Lang NP. Survival and failure rates of orthodontic temporary anchorage devices: a systematic review. Clin Oral Implants Res. 2009;20(12):1351-1359. doi: https://doi.org/10.1111/j.1600-0501.2009.01754.x.
20. Ramírez-Ossa DM, Escobar-Correa N, Ramírez-Bustamante MA, Agudelo-Suárez AA. An umbrella review of the effectiveness of temporary anchorage devices and the factors that contribute to their success or failure. J Evid Based Dent Pract. 2020;20(2):101402. doi: https://doi.org/10.1016/j.jebdp.2020.101402.
21. Meursinge Reynders RA, Ronchi L, Ladu L, van Etten-Jamaludin F, Bipat S. Insertion torque and success of orthodontic mini-implants: a systematic review. Am J Orthod Dentofacial Orthop. 2012;142(5):596-614.e5. doi: https://doi.org/10.1016/j.ajodo.2012.06.013.
22. Tseng YC, Pan CY, Liu PH, Yang YH, Chang HP, Chen CM. Resonance frequency analysis of miniscrew implant stability. J Oral Sci. 2018;60(1):64-69. doi: https://doi.org/10.2334/josnusd.16-0613.
23. Ichinohe M, Motoyoshi M, Inaba M, Uchida Y, Kaneko M, Matsuike R, et al. Risk factors for failure of orthodontic mini-screws placed in the median palate. J Oral Sci. 2019;61(1):13-18. doi: https://doi.org/10.2334/josnusd.17-0377.
24. Ikenaka R, Koizumi S, Otsuka T, Yamaguchi T. Effects of root contact length on the failure rate of anchor screw. J Oral Sci. 2022;64(3):232-235. doi: https://doi.org/10.2334/josnusd.21-0536.
25. Azeem M, Ul Haq A, Awaisi ZH, Saleem MM, Tahir MW, Liaquat A. Failure rates of miniscrews inserted in the maxillary tuberosity. Dental Press J Orthod. 2019;24(5):46-51. doi: https://doi.org/10.1590/2177-6709.24.5.046-051.oar.
26. Geshay D, Campbell P, Tadlock L, Schneiderman E, Kyung HM, Buschang P. Stability of immediately loaded 3 mm long miniscrew implants: a feasibility study. Dental Press J Orthod. 2021;26(1):e2119155. doi: https://doi.org/10.1590/2177-6709.26.1.e2119155.oar.
27. Centeno ACT, Fensterseifer CK, Chami VO, Ferreira ES, Marquezan M, Ferrazzo VA. Correlation between cortical bone thickness at mini-implant insertion sites and age of patient. Dental Press J Orthod. 2022;27(1):e222098. doi: https://doi.org/10.1590/2177-6709.27.1.e222098.oar.
28. Ashil AM, Sharma A, Jose LK, Grover S, Kochar AS, Varghese ST, et al. A CBCT assessment of orthodontic mini-implant placement. J Pharm Bioallied Sci. 2024;16(Suppl 1):S927-S929. doi: https://doi.org/10.4103/jpbs.jpbs_1102_23.
29. Yassaei S, Kordi S, Aghili H, Zavar Reza J, Ebrahiminik Z. Diode laser irradiation effects on miniscrew stability and IL-1β and TGF-β1 levels: a split-mouth randomized controlled clinical trial. J Lasers Med Sci. 2023;14:e3. doi: https://doi.org/10.34172/jlms.2023.03.
30. Lee Y, Choi SH, Yu HS, Erenebat T, Liu J, Cha JY. Stability and success rate of dual-thread miniscrews: a retrospective study using the buccal alveolar region as the insertion site. Angle Orthod. 2021;91(4):509-514. doi: https://doi.org/10.2319/083020-756.1.
31. Singh J, Singh SK, Gupta AR, Nayak SC, Vatsa R, Priyadarshni P. Comparative evaluation of primary stability of two different types of orthodontic mini-implants. J Pharm Bioallied Sci. 2021;13(Suppl 1):S128-S131. doi: https://doi.org/10.4103/jpbs.JPBS_604_20.
32. Song YL, Yow M, Chew MT, Foong KWC, Wong HC. A study of success rate of miniscrew implants as temporary anchorage devices in Singapore. Int J Dent. 2015;2015:294670. doi: https://doi.org/10.1155/2015/294670.
33. Sahoo SN, Pattanaik S, Nanda SB, Mohammad N, Khan A, Pani S. Patients’ perceptions and success rate of temporary anchorage devices after the immediate and delayed loading of orthodontic mini-implants-randomized clinical trial. J Pharm Bioallied Sci. 2024;16(Suppl 5):S4396-S4399. doi: https://doi.org/10.4103/jpbs.jpbs_750_24.
34. He Y, Liu J, Huang R, Chen X, Jia X, Zeng N, et al. Clinical analysis of successful insertion of orthodontic mini-implants in infrazygomatic crest. BMC Oral Health. 2023;23(1):348. doi: https://doi.org/10.1186/s12903-023-03081-0.
35. Yildiz MS, Ulutas PA, Ozenci I, Akcalı A. Clinical and radiographic assessment of the association between orthodontic mini-screws and periodontal health. BMC Oral Health. 2024;24(1):1376. doi: https://doi.org/10.1186/s12903-024-05136-2.
36. Kalra S, Tripathi T, Rai P, Kanase A. Evaluation of orthodontic mini-implant placement: a CBCT study. Prog Orthod. 2014;15(1):61. doi: https://doi.org/10.1186/s40510-014-0061-x.
37. Athira VM, Shashidhar K, Kuttappa MN, Nayak USK, Ravi MS, D’Souza N. Safe sites for buccal shelf bone screw placement in various skeletal malocclusions: a CBCT study. J Orthod Sci. 2023;12:63. doi: https://doi.org/10.4103/jos.jos_13_23.
38. Garg H, Ahluwalia R, Grewal SB, Pandey SK, Mahesh A, Saini N. Stainless steel vs. titanium miniscrew implants: evaluation of stability during retraction of maxillary and mandibular anterior teeth. J Orthod Sci. 2022;11:49. doi: https://doi.org/10.4103/jos.jos_198_21.
39. Bollero P, Di Fazio V, Pavoni C, Cordaro M, Cozza P, Lione R. Titanium alloy vs. stainless steel miniscrews: an in vivo split-mouth study. Eur Rev Med Pharmacol Sci. 2018;22(8):2191-2198. doi: https://doi.org/10.26355/eurrev_201804_14803.
40. Chawshli OF, Hasan HS, Yalda FA, Al-Talabani SZ. The success rate of mini-screws for incisors intrusion and patient age, gender, and insertion angle in the maxilla using CBCT and implant-guided surgery. A split-mouth, randomized control trail. Orthod Craniofac Res. 2024;27(1):118-125. doi: https://doi.org/10.1111/ocr.12700.
41. Li X, Liu J, Xu J, Yang Y, Wang J, Zhang X. Cone beam computed tomography references for placement site and insertion angle of a palatal orthodontic miniscrew in the posterior maxillary area. Research Square [Preprint]. 2022 Jan 18. doi: https://doi.org/10.21203/rs.3.rs-1218146/v1.

back