Non-Cochrane · intervention · PM42270616
Comparative impact of clear aligners versus fixed orthodontic appliances on periodontal health, pain, and quality of life: a systematic review and meta-analysis.
Kaur Kanwalpreet, Quadri Syed Altafuddin, Saini Ravinder S, et al. · BDJ open · 2026 · PubMed · doi:10.1038/s41405-026-00450-z
Findings
Population Patients undergoing orthodontic treatment (all ages)
19 findings
| Clear aligners (Invisalign and similar removable aligners) | Fixed orthodontic appliances (metal, self-ligating, ceramic, lingual brackets) | Probing depth All reported follow-up · Sensitivity analysis (Suppl. Table S3 base pooled effect) | SMD -0.681 GRADE not reported Studies not reported |
| Clear aligners (Invisalign and similar removable aligners) | Fixed orthodontic appliances (metal, self-ligating, ceramic, lingual brackets) | Quality of life 3 months · Follow-up duration: 3 months | SMD -0.590 [-1.194, 0.013] GRADE not reported 1 study |
| Clear aligners (Invisalign and similar removable aligners) | Fixed orthodontic appliances (metal, self-ligating, ceramic, lingual brackets) | Probing depth All reported follow-up | MD -0.332 [-0.431, -0.234] High 8 studies · 445 participants |
| Clear aligners (Invisalign and similar removable aligners) | Fixed orthodontic appliances (metal, self-ligating, ceramic, lingual brackets) | Plaque index All reported follow-up (up to 18 months) Unresolved: the two extractors disagree on this row. | MD -0.437 [-0.507, -0.367] GRADE not reported 12 studies · 687 participants |
| Clear aligners (Invisalign and similar removable aligners) | Fixed orthodontic appliances (metal, self-ligating, ceramic, lingual brackets) | Quality of life 10 days · Follow-up duration: 10 days | SMD -0.895 [-1.426, -0.364] GRADE not reported 1 study |
| Clear aligners (Invisalign and similar removable aligners) | Fixed orthodontic appliances (metal, self-ligating, ceramic, lingual brackets) | Quality of life 20 days · Follow-up duration: 20 days | SMD -0.895 [-1.426, -0.364] GRADE not reported 1 study |
| Clear aligners (Invisalign and similar removable aligners) | Fixed orthodontic appliances (metal, self-ligating, ceramic, lingual brackets) | Quality of life All follow-up durations (1 week to end of treatment) Unresolved: the two extractors disagree on this row. | SMD -0.850 [-0.973, -0.727] Moderate Downgraded: inconsistency 16 studies · 856 participants |
| Clear aligners (Invisalign and similar removable aligners) | Fixed orthodontic appliances (metal, self-ligating, ceramic, lingual brackets) | Quality of life End of treatment · Follow-up duration: End of treatment | SMD -0.970 [-1.412, -0.528] GRADE not reported 2 studies |
| Clear aligners (Invisalign and similar removable aligners) | Fixed orthodontic appliances (metal, self-ligating, ceramic, lingual brackets) | Gingival index All reported follow-up | MD -0.233 [-0.296, -0.170] High 7 studies · 412 participants |
| Clear aligners (Invisalign and similar removable aligners) | Fixed orthodontic appliances (metal, self-ligating, ceramic, lingual brackets) | Quality of life 2 weeks · Follow-up duration: 2 weeks | SMD -0.734 [-1.172, -0.397] GRADE not reported 2 studies |
| Clear aligners (Invisalign and similar removable aligners) | Fixed orthodontic appliances (metal, self-ligating, ceramic, lingual brackets) | Pain intensity All follow-up time points (1 week to 6 months) Unresolved: the two extractors disagree on this row. | SMD -0.419 [-0.536, -0.302] Moderate Downgraded: publication bias 18 studies · 892 participants |
| Clear aligners (Invisalign and similar removable aligners) | Fixed orthodontic appliances (metal, self-ligating, ceramic, lingual brackets) | Quality of life 1 week · Follow-up duration: 1 week | SMD -0.985 [-1.272, -0.699] GRADE not reported 3 studies |
| Clear aligners (Invisalign and similar removable aligners) | Fixed orthodontic appliances (metal, self-ligating, ceramic, lingual brackets) | Plaque index All reported follow-up · Study design: randomized controlled trials | MD -0.667 [-1.019, -0.315] GRADE not reported 5 studies |
| Clear aligners (Invisalign and similar removable aligners) | Fixed orthodontic appliances (metal, self-ligating, ceramic, lingual brackets) | Quality of life 6 months · Follow-up duration: 6 months | SMD -0.850 [-1.144, -0.557] GRADE not reported 4 studies |
| Clear aligners (Invisalign and similar removable aligners) | Fixed orthodontic appliances (metal, self-ligating, ceramic, lingual brackets) | Quality of life 1 month · Follow-up duration: 1 month | SMD -0.829 [-1.081, -0.577] GRADE not reported 4 studies |
| Clear aligners (Invisalign and similar removable aligners) | Fixed orthodontic appliances (metal, self-ligating, ceramic, lingual brackets) | Plaque index All reported follow-up · Sensitivity analysis (Suppl. Table S3 base pooled effect) | SMD -0.959 [-1.148, -0.770] GRADE not reported Studies not reported |
| Clear aligners (Invisalign and similar removable aligners) | Fixed orthodontic appliances (metal, self-ligating, ceramic, lingual brackets) | Plaque index All reported follow-up · Study design: non-randomized studies | MD -0.457 [-0.563, -0.350] GRADE not reported 6 studies |
| Clear aligners (Invisalign and similar removable aligners) | Fixed orthodontic appliances (metal, self-ligating, ceramic, lingual brackets) | Quality of life 12 months · Follow-up duration: 12 months | SMD -0.531 [-1.178, 0.116] GRADE not reported 1 study |
| Clear aligners (Invisalign and similar removable aligners) | Fixed orthodontic appliances (metal, self-ligating, ceramic, lingual brackets) | Probing depth All reported follow-up · Trim-and-fill adjusted (2 missing studies imputed) | MD -0.348 [-0.444, -0.253] GRADE not reported Studies not reported |
Included primary studies 32
Open in Studies| Study | Year | Also included by | Outcomes it informs here | Trial data |
|---|---|---|---|---|
| Alfawal 2022 The impact of non-extraction orthodontic treatment on oral health-related quality of life: clear aligners versus fixed appliances-a… PMID:35395075 | 2022 | 3 other reviews | Quality of life | not extracted yet |
| Karkhanechi 2013 Periodontal status of adult patients treated with fixed buccal appliances and removable aligners over one year of active orthodontic… PMID:22725616 | 2013 | 3 other reviews | Plaque index; Gingival index; Probing depth | not extracted yet |
| Levrini 2015 Periodontal health status in patients treated with the Invisalign(®) system and fixed orthodontic appliances: A 3 months clinical and… PMID:26430371 | 2015 | 3 other reviews | Plaque index; Probing depth | not extracted yet |
| Antonio-Zancajo 2020 Pain and Oral-Health-Related Quality of Life in Orthodontic Patients During Initial Therapy with Conventional, Low-Friction, and Lingual… PMID:32635196 | 2020 | 2 other reviews | Pain intensity; Quality of life | not extracted yet |
| Gao 2021 Comparison of pain perception, anxiety, and impacts on oral health-related quality of life between patients receiving clear aligners and… PMID:32613250 | 2021 | 2 other reviews | Pain intensity; Quality of life | not extracted yet |
| Miethke 2005 A comparison of the periodontal health of patients during treatment with the Invisalign system and with fixed orthodontic appliances. PMID:15959635 | 2005 | 2 other reviews | Plaque index; Gingival index; Probing depth | not extracted yet |
| Miller 2007 A comparison of treatment impacts between Invisalign aligner and fixed appliance therapy during the first week of treatment. PMID:17346581 | 2007 | 2 other reviews | Pain intensity; Quality of life | not extracted yet |
| Tunca 2024 Comparison of anxiety, pain, and quality of life in individuals with mild or moderate malocclusion between conventional fixed orthodontic… PMID:38760747 | 2024 | 2 other reviews | Pain intensity; Quality of life | not extracted yet |
| Abbate 2015 Periodontal health in teenagers treated with removable aligners and fixed orthodontic appliances. PMID:25929710 | 2015 | 1 other review | Plaque index; Probing depth | not extracted yet |
| Alcon 2021 matched by author and year (probable) | NR | 1 other review | Pain intensity | not extracted yet |
| Almasoud 2018 Pain perception among patients treated with passive self-ligating fixed appliances and Invisalign® aligners during the first week of… PMID:30206531 | 2018 | 1 other review | Pain intensity | not extracted yet |
| Azaripour 2015 Braces versus Invisalign®: gingival parameters and patients' satisfaction during treatment: a cross-sectional study. PMID:26104387 | 2015 | 1 other review | Gingival index | not extracted yet |
| Borsato 2025 Impact of orthodontic treatment with aligners and fixed appliances on OHRQoL: a randomized clinical trial. PMID:39936711 | 2025 | 1 other review | Quality of life | not extracted yet |
| Chhibber 2018 Which orthodontic appliance is best for oral hygiene? A randomized clinical trial. PMID:29407494 | 2018 | 1 other review | Plaque index; Gingival index | not extracted yet |
| Flores-Mir 2018 Patient satisfaction and quality of life status after 2 treatment modalities: Invisalign and conventional fixed appliances. PMID:30384934 | 2018 | 1 other review | Quality of life | not extracted yet |
| Fujiyama 2014 Analysis of pain level in cases treated with Invisalign aligner: comparison with fixed edgewise appliance therapy. PMID:25416143 | 2014 | 1 other review | Pain intensity | not extracted yet |
| Shalish 2012 Adult patients' adjustability to orthodontic appliances. Part I: a comparison between Labial, Lingual, and Invisalign™. PMID:21750242 | 2012 | 1 other review | Pain intensity | not extracted yet |
| White 2017 Discomfort associated with Invisalign and traditional brackets: A randomized, prospective trial. PMID:28753032 | 2017 | 1 other review | Pain intensity | not extracted yet |
| Withayanukonkij 2023 Root resorption during maxillary molar intrusion with clear aligners: a randomized controlled trial. PMID:37922387 | 2023 | 1 other review | not stated | not extracted yet |
| Zamora-Martinez 2021 Comparative Study of Oral Health-Related Quality of Life (OHRQL) between Different Types of Orthodontic Treatment. PMID:34356964 | 2021 | 1 other review | Quality of life | not extracted yet |
| Bollen 2003 Activation time and material stiffness of sequential removable orthodontic appliances. Part 1: Ability to complete treatment. PMID:14614415 | 2003 | this review only | not stated | not extracted yet |
| Casteluci 2021 Evaluation of pain intensity in patients treated with aligners and conventional fixed appliances: Randomized clinical trial. PMID:33058419 | 2021 | this review only | Pain intensity | not extracted yet |
| Dubey 1993 Oral hygiene and gingival status in orthodontic patients. PMID:9791270 | 1993 | this review only | Plaque index; Gingival index | not extracted yet |
| Hennessy 2016 A randomized clinical trial comparing mandibular incisor proclination produced by fixed labial appliances and clear aligners. PMID:27571371 | 2016 | this review only | not stated | not extracted yet |
| Leyva 2023 Orthognathic surgery and aligners. A comparative assessment of periodontal health and quality of life in postsurgical orthodontic… PMID:37026606 | 2023 | this review only | Pain intensity; Plaque index; Probing depth; Quality of life | not extracted yet |
| Lin 2022 Differences in finished case quality between Invisalign and traditional fixed appliances. PMID:35168256 | 2022 | this review only | Quality of life | not extracted yet |
| Melo 2021 Effects of orthodontic treatment with aligners and fixed appliances on speech. PMID:34037699 | 2021 | this review only | not stated | not extracted yet |
| Miethke 2007 A Comparison of the periodontal health of patients during treatment with the Invisalign system and with fixed lingual appliances. PMID:17522806 | 2007 | this review only | Plaque index; Gingival index; Probing depth | not extracted yet |
| Pereira 2021 Frequency of awake bruxism behaviour in orthodontic patients: Randomised clinical trial: Awake bruxism behaviour in orthodontic patients. PMID:33278836 | 2021 | this review only | not stated | not extracted yet |
| Petti 1997 Effect of orthodontic therapy with fixed and removable appliances on oral microbiota: a six-month longitudinal study. PMID:9037669 | 1997 | this review only | Plaque index; Probing depth | not extracted yet |
| Rego 2010 Clinical and microbiological studies of children and adolescents receiving orthodontic treatment. PMID:21344829 | 2010 | this review only | Plaque index; Gingival index; Probing depth | not extracted yet |
| Silva 2023 Comparison between clear aligners and 2 × 4 mechanics in the mixed dentition: a randomized clinical trial. PMID:36066265 | 2023 | this review only | Plaque index | not extracted yet |
Overlap with other reviews
Reviews that include the same primary studies are not independent evidence. Shared counts match studies by PMID, DOI or NCT, and otherwise by author and year (a probable match). Only the non-Cochrane dental reviews have study lists, so overlap with Cochrane reviews is not counted yet.
Review question
| Element | Planned (methods) | Found (results) |
|---|---|---|
| Population | Patients undergoing orthodontic treatment for malocclusion, all ages and sexes; excluded severe periodontal disease, craniofacial anomalies, orthognathic surgery | Orthodontic patients of all ages (children to adults), 32 studies, sample sizes 28 to 145 |
| Intervention | Clear aligner therapy (Invisalign and similar removable appliances) | Clear aligners (Invisalign, orthodontic aligners, removable appliances) |
| Comparison | Fixed orthodontic appliances (conventional metal braces, self-ligating brackets, ceramic braces) | Fixed labial appliances, self-ligating brackets, lingual braces, traditional metal appliances |
| Outcomes | Quality of life, plaque index, gingival index, probing depth, pain perception; secondary: treatment duration, patient-reported discomfort | Pain intensity (SMD), plaque index (MD), gingival index (MD), probing depth (MD), quality of life (SMD) |
| Study designs | RCTs, cohort studies, case-control studies | 17 RCTs and 15 observational studies (28 in the meta-analysis) |
| Timing | Short-term (1 week to 1 month) versus long-term (12 months or more) follow-up | 1 week to end of treatment (up to 12 months for quality of life) |
AMSTAR 2 items
Two independent extractors rated each item. Their ratings are shown side by side because they have not been reconciled yet. The overall rating follows Shea et al. 2017: one critical flaw gives Low, more than one gives Critically Low.
| Item | Extractor A | Extractor B | Agree |
|---|---|---|---|
| 1Research question includes PICO components | Yes | Yes | yes |
| 2Protocol established before the reviewcritical | Partial Yes | Partial Yes | yes |
| 3Choice of study designs explained | Yes | Yes | yes |
| 4Comprehensive literature searchcritical | Partial Yes | Partial Yes | yes |
| 5Study selection in duplicate | Yes | Yes | yes |
| 6Data extraction in duplicate | No | No | yes |
| 7List of excluded studies with reasonscritical | No | No | yes |
| 8Included studies described in detail | Partial Yes | Partial Yes | yes |
| 9Risk of bias assessed satisfactorilycritical | RCT: Yes · NRSI: Yes | NRSI: Yes · RCT: Yes | no |
| 10Funding of included studies reported | No | No | yes |
| 11Appropriate meta-analysis methodscritical | RCT: No · NRSI: No | NRSI: No · RCT: No | no |
| 12Impact of risk of bias on the pooled results | No | No | yes |
| 13Risk of bias accounted for in interpretationcritical | Yes | Yes | yes |
| 14Heterogeneity explained | Yes | Yes | yes |
| 15Publication bias investigatedcritical | Yes | Yes | yes |
| 16Conflicts of interest reported | Yes | Yes | yes |
| Overall | Critically Low | Critically Low | yes |