Reference

Zheng M, Liu R, Ni Z, Yu Z. Efficiency, effectiveness and treatment stability of clear aligners: A systematic review and meta-analysis.
Orthodontics & Craniofacial Research. 2017 Aug;20(3):127-133.
DOI: 10.1111/ocr.12177
PMID: 28547915

Background

Clear aligner therapy has become an important alternative to conventional fixed orthodontic appliances because of its aesthetic advantages and improved patient comfort. However, questions remain regarding treatment efficiency, predictability of tooth movement and long-term stability compared with traditional orthodontic techniques.

Objective

The aim of this systematic review and meta-analysis was to evaluate the efficiency, clinical effectiveness and treatment stability of clear aligner therapy based on available scientific evidence.

Materials and Methods

The authors performed a systematic review of published studies evaluating orthodontic treatment outcomes using clear aligners. Clinical parameters related to treatment duration, effectiveness and stability were analyzed and compared with conventional orthodontic approaches when available.

Results

The analysis showed that clear aligners can provide satisfactory orthodontic results, particularly in cases involving mild to moderate malocclusions.

Compared with fixed appliances, clear aligners demonstrated advantages in patient comfort and aesthetic acceptance. However, limitations were observed for complex tooth movements requiring precise biomechanical control.

Treatment predictability was influenced by the type of tooth movement, treatment planning accuracy and patient compliance.

Main Scientific Findings

• Clear aligners are effective for selected orthodontic indications.
• Patient satisfaction is generally higher due to improved aesthetics and comfort.
• Complex movements remain less predictable compared with fixed appliances.
• Long-term stability depends on appropriate retention protocols.

Conclusion

The authors concluded that clear aligner therapy is an effective orthodontic treatment option in appropriately selected patients. Nevertheless, current evidence indicates that treatment planning, case selection and clinician experience remain essential to obtain predictable results.

Clinical Relevance for Orthodontists

Clear aligners should be considered as an additional therapeutic modality rather than a complete replacement for fixed appliances. Their success depends on understanding biomechanical limitations and selecting cases where predictable tooth movement can be achieved.

Keywords

Clear aligners; Invisalign; orthodontic treatment; systematic review; meta-analysis; treatment outcomes; digital orthodontics.