Abstract
Background: This systematic review aimed to compare the pain discomfort levels between InvisalignⓇ aligners comparing with traditional fixed appliances at multiple time points, through Pain Visual Analog Scale (VAS).
Methods: Four electronic databases (Pubmed, Medline, CENTRAL and Scholar) were searched up to February 2019. There were no restrictions on year and publication status. Randomized clinical trials (RCTs) and case-control studies comparing pain perception through VAS in patients treated with Invisalign aligners and with labial appliances were included. Risk of bias within and across studies was assessed using Cochrane tool and Newcastle-Ottawa Scale (NOS) approach. Random-effects meta-analysis were conducted. VAS score at 1, 3 and 7 days, and analgesic consumption was collected. Pairwise and Binary Random-Effects Meta-analyses were used to synthesize available data.
Results: At the initial search, a total of 87 articles were retrieved. Following the review protocol, 4 articles met the inclusion criteria and were included, with a total of 214 participants (139 females, 75 males). All studies were considered of high methodological quality. The results demonstrate that Invisalign aligners seems to be associated with significantly less pain than fixed appliances at 7 days after beginning the orthodontic treatment, although at 1 and 3 days the pain experience was similar in both orthodontics appliances. In regard to the type of material, SmartTrackⓇ aligners appear to give significantly better comfort for orthodontic patients than previous standard material, being that 3 days after appliance’s insertion this pain differential becomes significant, and this difference is more pronounced at 7 days.
Conclusion: Patients treated with Invisalign experience less pain discomfort than those treated with fixed appliances and consume less analgesics. Overall, Invisalign promotes better pain and discomfort experience for the patient in the course of orthodontic treatment. Larger RCTs are needed to definitely demonstrate these findings throughout the orthodontic treatment.