Use of electrical stimulation for accelerated orthodontics in humans: a systematic review and meta-analysis

The main objective of this systematic review is to comprehensively evaluate all the relevant studies to evaluate the effectiveness of electrical stimulation to accelerate orthodontic tooth movement in human patients.

Using a suitable search strategy, various databases like PubMed, CENTRAL, Scopus and Google Scholar were surveyed for relevant randomized controlled trials (RCTs); after which a hand search of related orthodontic journals was completed. The risk of bias of studies was checked using Cochrane's ROB-2 tool. The quality of evidence of the included studies was evaluated using the Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) framework. Rate of orthodontic tooth movement was compared and thus efficiency of electrical stimulation to accelerate tooth movement was assessed. Meta-analysis was done on 2 studies out of the 4; rate of orthodontic tooth movement was compared at two time periods after start of treatment (3^rd month and 5^th month) with standardized mean difference (SMD) as summary estimate, with p < 0.05 denoting statistical significance. Publication bias was checked using a funnel plot.

Via exploration of the online databases and hand searching, 1080 studies were found after removing duplicates. After full text assessment, 13 studies in total were selected that used electrical stimulation, out of which 4 studies were included in the qualitative analysis as they met the inclusion criteria. The meta-analysis was done for 3^rd month and 5^th month with SMD as 0.69(-1.26-0.12) and 1.64(-3.44-0.16), respectively. The strength of evidence in the meta-analysis is moderate. There was no publication bias as shown by funnel plot.

The studies included showed increased risk of selection and performance bias. Also due to the limited number of studies available, there was difficulty in reaching definitive conclusions. The meta-analysis showed a significant difference among the control and experimental group for the 3^rd month.

Even though a positive correlation is found between electrical stimulation and acceleration of orthodontic tooth movement, it is advised to conduct further studies, particularly with human participants, to establish a more conclusive outcome.

This review has received no funding. The protocol for the study was registered in the Prospective Registration of Systematic Review (PROSPERO)(CRD42023495077).