Trial reportThe Angle orthodontist2024
Evaluation of anchorage loss after en masse retraction in orthodontic patients with maxillary protrusion using friction vs frictionless mechanics: randomized clinical trial.
Trial report in The Angle orthodontist, 2024. The graph could read no effect estimate from its abstract, so it casts no vote on the map. An erratum has been issued. It is linked to trial NCT06928896 (Friction or Frictionless), which is not on this map. Cited by 6 papers, 2 of them syntheses that pooled it.
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.
Friction or Frictionless: What is the Most Effective Method for Retracting Anterior Teeth?
Who cites it
6 citing papers in PubMed, 2 syntheses or guidelines pooled it.
- Radiographic assessment and orthodontic intervention effects on orthodontically induced root resorption: a systematic review and meta-analysis of clinical trials.Acta odontologica Scandinavica · 2026Pooled it
- Methods of incisor inclination control during the non-accelerated retraction of upper anterior teeth with fixed orthodontic appliances: a systematic review and meta-analysis.BMC oral health · 2026Pooled it
- Beyond Sagittal and Vertical: Transverse Constriction as a Feature of the Collapsed Arch in Angle Class II Post-Extraction Retreatment Patients: A Retrospective CBCT Pilot Study.Healthcare (Basel, Switzerland) · 2026Article
- Biomechanical analysis of interradicular and infrazygomatic miniscrew anchorage during two-step and en-masse retraction: A finite element study.BMC oral health · 2026Article
- Space closure rate and anchorage control during maxillary anterior en-masse retraction using bidimensional versus conventional sliding mechanics.Bioinformation · 2026Article
- Three-dimensional CBCT analysis of bone remodeling, root resorption, and incisive canal morphology during miniscrew-assisted aligner-based incisor retraction with and without extractions.Frontiers in oral health · 2026Article
Corrections and comments
- Erratum issuedErratum.2025
Authors and funding
5 authors.
Funding
No grant is acknowledged in the PubMed record.
Abstract
objectivesTo evaluate anchorage loss after en masse retraction in bimaxillary dentoalveolar protrusion patients using friction vs frictionless mechanics. MATERIALS AND
methodsThirty patients with bimaxillary dentoalveolar protrusion needing extraction of upper first premolars and en masse retraction with maximum anchorage were included in this two-arm, parallel, single-center, single-blinded randomized clinical trial with a 1:1 allocation ratio using fully sealed opaque envelopes. Friction group retraction utilized elastomeric power chain between miniscrews and hooks crimped mesial to upper canines on 17 × 25 stainless steel archwire. Frictionless group used customized T-loop springs loading upper first molars indirectly anchored to miniscrews. Activation was every 4 weeks until full retraction. The primary outcome assessed was anchorage loss evaluated at cusp tip and root apex of the first molar. First molar rotation, incisor tip and torque, and root resorption of anterior teeth were evaluated on digital models and cone beam computed tomography taken before and after space closure.
resultsAnchorage loss at crown of first molar was significantly more in frictionless group by 2.1 mm (95% CI = -0.4 to 3.5), (P = .014), while there was no significant difference in anchorage loss at root apex between groups. Significant mesial in molar rotation of 6.672° (95% CI = 12.2-21.2), (P = 0.02) was greater in the frictionless group. Both groups showed comparable tip, torque, and root resorption values. No severe harms were reported. There was mild gingival overgrowth and inflammation in the frictionless group due to T-loop irritation.
conclusionsExtra anchorage considerations are needed during en masse retraction when frictionless mechanics is implemented as higher anchorage loss and molar rotation were detected. No difference in tip, torque, and root resorption was observed.
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