Title Nickel Titanium Closing Springs Are More Effective Than Elastomeric Power Chains for Orthodontic Space Closure
Clinical Question In an orthodontic patient, will a nickel titanium closing spring as compared to an elastomeric power chain lead to faster space closure?
Clinical Bottom Line For orthodontic patients, a nickel titanium closing spring is more effective than an elastomeric power chain for space closure. This is based on a systematic review and meta-analysis of four randomized clinical trials (RCTs) that included 290 quadrants where nickel titanium closing springs led to faster space closure compared to elastomeric power chains. Nickel titanium closing springs are well within the expertise of the average orthodontic practice and likely to be accepted by the average orthodontic patient.
Best Evidence  
PubMed ID Author / Year Patient Group Study type
(level of evidence)
29265578Mohammed/2017290 quadrants from 4 studies (RCTs)Systematic review of randomized trials
Key resultsBoth nickel titanium closing springs and elastomeric power chains are effective treatment modalities for space closure. However, nickel titanium closing springs were shown to lead to faster space closure by a mean difference of 0.20 millimeters per month (95% CI: 0.12-0.28) compared to elastomeric power chains. With the exception of anchorage loss, this systematic review and meta-analysis did not include secondary outcomes to space closure such as adverse periodontal effects or patient preferences.
Evidence Search “niti closing springs” AND “elastomeric power chains”
Comments on
The Evidence
Mohammed systematically reviewed literature in 2017 by searching several databases (CENTRAL, MEDLINE, EMBASE, Scopus, LILACS and Web of Science). 11 articles were initially assessed but only 4 articles met the inclusion criteria. All 4 studies were human randomized clinical trials, two of which implemented a split-mouth design and the other two, a parallel-group design. Each study was assessed for bias using Cochrane’s collaboration tool and found to have either unclear or high risk of bias. Each study reported the mean rate of space closure per month except one study which reported space closure after 4 months. Overall, 290 quadrants treated with either a nickel titanium closing spring or an elastomeric power chain were evaluated. The studies were assessed as having moderate quality evidence proposing that nickel titanium closing springs generate a faster rate of space closure by a mean difference of 0.20 millimeters per month (95% CI: 0.12-0.28) compared to elastomeric power chains. Two studies measured anchorage loss but there was no statistical difference between the two. There was no or little heterogeneity between the studies indicating that the effect of the intervention was true and accurate.
Applicability This systematic review and meta-analysis included orthodontic patients of any age that were currently undergoing orthodontic treatment with fixed, conventional-ligation appliances and required space closure secondary to premolar extraction. The evidence suggested that nickel titanium closing springs produced a faster rate of space closure compared to elastomeric power chains by a mean difference of 0.20mm/month. The studies included in this systematic review did not effectively evaluate adverse periodontal effects, cost efficiency or patient-centered outcomes. As such, careful consideration of these factors may need to be implemented on a case-by-case basis.
Specialty (Orthodontics)
Keywords niti closing springs, elastomeric power chains
ID# 3468
Date of submission 11/22/2021
E-mail evansb1@livemail.uthscsa.edu
Author Brandy Evans, DDS
Co-author(s) Turki Althenyan, BDS
Co-author(s) e-mail althenyan@livemail.uthscsa.edu
Faculty mentor Ravikumar Anthony, BDS, MDS, MS
Faculty mentor e-mail anthonyr@uthscsa.edu
Basic Science Rationale
(Mechanisms that may account for and/or explain the clinical question, i.e. is the answer to the clinical question consistent with basic biological, physical and/or behavioral science principles, laws and research?)
None available
Comments and Evidence-Based Updates on the CAT
None available