Effectiveness of Low-Level Laser Therapy in Reducing Orthodontic Pain: A Systematic Review and Meta-Analysis

Table 4

GRADE quality evidence.

Outcomes	N. of participants; (studies)	Quality of the evidence; (GRADE)	Anticipated absolute effects
			Risk with placebo	Risk difference with pain laser
Spontaneous pain 24 h, elastomeric separators	203 participants; (4 RCTs)	⨁⨁◯◯; low	—	SMD 0.76 SD lower; (1.19 lower to 0.33 lower)
Spontaneous pain 24 h, archwire placement	60 participants; (2 RCTs)	⨁⨁◯◯; low	—	SMD 2.09 lower; (4.1 lower to 0.09 lower)
Spontaneous pain 72 h, elastomeric separators	185 participants; (3 RCTs)	⨁⨁◯◯; low	—	SMD 0.54 lower; (0.91 lower to 0.17 lower)
Spontaneous pain 72 h, archwire placement	20 participants; (1 RCT)	⨁⨁◯◯; low	—	SMD 1.54 lower; (2.57 lower to 0.51 lower)
Chewing pain 24 h, elastomeric separators	160 participants; (3 RCTs)	⨁⨁◯◯; low	—	SMD 0.99 lower; (1.28 lower to 0.7 lower)
Chewing pain 72 h, elastomeric separators	160 participants; (3 RCTs)	⨁⨁◯◯; low	—	SMD 0.68 lower; (1.03 lower to 0.32 lower)

CI, confidence interval; SMD, standardised mean difference; 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; explanations: the evidence was downgraded by two levels because of very serious concern regarding the risk of bias; one study had high risk in random sequence generation, two studies did not report information regarding allocation concealment, and two studies had a high risk of performance bias; the evidence was downgraded by one level because one study had high risk regarding selective report and small number of participants; the evidence was downgraded by two levels because of very serious concern regarding the risk of bias; one study had high risk in random sequence generation, two studies did not report information regarding allocation concealment, and one study had a high risk of performance bias; the evidence was downgraded by one level because one study had high risk regarding selective report and one level because it is single study (indirectness); the evidence was downgraded by two levels because of very serious concern regarding the risk of bias; one study did not report information regarding allocation concealment and two studies had a high risk of performance bias.