SynthesisProgress in orthodontics2026
Predicting transversal dental arch expansion outcomes with Invisalign aligners in permanent dentition: a systematic review and meta-analysis.
Synthesis in Progress in orthodontics, 2026. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 2 papers.
What it found
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The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.
The trial behind it
Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.
Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.
Who cites it
2 citing papers in PubMed.
- Clinical trends and utilization of clear aligner therapy among specialist orthodontists in Iran.Frontiers in oral health · 2026Article
- Clear aligner therapy: a scoping review of treatment prediction, clinical effectiveness, and limitations.Frontiers in dental medicine · 2026Review
Corrections and comments
PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.
Authors and funding
5 authors.
Funding
No grant is acknowledged in the PubMed record.
Abstract
objectiveTo evaluate the predictability of Invisalign in producing transverse dental arch expansion in permanent dentition and to identify clinical and methodological factors influencing expansion accuracy.
methodsA systematic search of PubMed, Embase, Scopus, and WOS (up to November 2025) identified clinical studies reporting planned and achieved expansion. Predictability was defined as the achieved-to-planned expansion ratio and synthesized as logit-transformed proportions in random-effects meta-analyses. Tooth-group-specific pooled estimates were calculated for each arch. Meta-regressions, non-parametric correlations, linear and multivariable regressions, and hierarchical clustering explored the influence of publication year, age, arch, tooth type, material, aligner-change interval, and planned/achieved expansion. Risk of bias was assessed with ROBINS-I and certainty of evidence with GRADE.
resultsTwenty-three studies (1391 patients) were included; 21 entered the meta-analyses. Average predictability was 75.5% in the maxilla and 80.6% in the mandible. Mandibular second premolars showed the highest pooled predictability (88%), whereas lower second molars were least reliable (73%). In subsets reporting both levels, gingival-margin predictability was consistently lower than cusp-level values. Prediction intervals were very wide in both arches. Meta-regressions showed small but significant reductions in predictability in more recent publications (p = 0.01) and with increasing patient age (p = 0.016); greater achieved expansion showed only a modest positive association with predictability. Multivariable regression identified younger age (p = 0.001), SmartTrack material (p < 0.001), and mandibular segments (p = 0.001) as independent predictors of higher predictability. Publication bias was evident, and overall certainty of evidence was rated very low.
conclusionsInvisalign aligners provide moderate-to-high predictability for dentoalveolar transverse expansion in permanent dentition, particularly in premolar regions and in the mandibular arch. Expansion is mainly expressed as buccal crown tipping. Age, aligner material, and arch location modestly influence outcomes, underscoring the need for biologically realistic planning, selective overcorrections, and careful case selection.
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Registered trials
Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the Socratic graph.