Summary of findings 3. Conventional nickel‐titanium (NiTi) versus superelastic NiTi arch wires.
| Conventional NiTi versus superelastic NiTi arch wires | ||||||
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Population: people receiving orthodontic treatment with fixed appliances
Settings: university clinics, faculty practices and private practices
Intervention: superelastic NiTi Control: conventional NiTi | ||||||
| Outcomes | Illustrative comparative risks* (95% CI) | Relative effect (95% CI) | Number of participants (studies) | Quality of the evidence (GRADE) | Comments | |
| Assumed risk | Corresponding risk | |||||
| Control | Superelastic NiTi | |||||
| Alignment rate between canines Little's Irregularity Index Follow‐up: about 5 weeks | Mean alignment rate in the control groups was
1.42 mm/about 5 weeks (1.34 mm per month) |
Mean alignment rate between canines in the intervention groups was 0.28 faster (0.33 slower to 0.89 faster) | 40 (1 study) | ⊕⊝⊝⊝ very low1,2 | Abdelrahman 2015a also reported no statistically significant difference of alignment rate over 8 or 16 weeks. | |
| Time to alignment Follow‐up: 16 weeks | Mean time to alignment in the control groups was 9.8 weeks | Mean time to alignment in the intervention groups was 0.3 longer (1.14 shorter to 1.74 longer) | 49 (1 study) | ⊕⊕⊝⊝ low2 | ||
| Pain day 1 VAS (0‐100 mm) Follow‐up: 7 days | Mean pain in the control groups was 37.8 | Mean pain day 1 in the intervention groups was 1.1 mm lower (15.1 lower to 12.9 higher) | 79 (1 study) | ⊕⊝⊝⊝ very low1,2 | MD of pain day 7 (multistrand stainless steel versus superelastic NiTi) was ‐0.40, 95% CI ‐4.61 to 3.81 RR of analgesic consumption within 7 days (multistrand stainless steel versus superelastic NiTi) was 2.58, 95% CI 0.52 to 12.81 |
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| Root resorption | Not measured | |||||
| *The basis for the assumed risk (e.g. the median control group risk across studies) is provided in footnotes. The corresponding risk (and its 95% confidence interval) is based on the assumed risk in the comparison group and the relative effect of the intervention (and its 95% CI). CI: confidence interval; MD: mean difference; NiTi: nickel‐titanium; RR: risk ratio | ||||||
| GRADE Working Group grades of evidence High quality: we are very confident that the true effect lies close to that of the estimate of the effect. Moderate quality: we are moderately confident in the effect estimate: the true effect is likely to be close to the estimate of the effect, but there is a possibility that it is substantially different. Low quality: our confidence in the effect estimate is limited: the true effect may be substantially different from the estimate of the effect. Very low quality: we have very little confidence in the effect estimate: the true effect is likely to be substantially different from the estimate of effect. | ||||||
1Downgraded one level due to serious risk of bias: one study at high risk. 2Downgraded two levels due to very serious imprecision.