Decalcification and bond failure rate in resin modified glass ionomer cement versus conventional composite for orthodontic bonding: A systematic review & meta-analysis

Background: Demineralized white spot lesions (DWSLs) are one of the unfavourable effects of orthodontic treatment. Resin modified glass ionomer cement (RMGIC) was introduced to reduce its occurrence. Objective: The study aimed to determine the incidence of DWSLs as primary objective and bond failure rate in brackets bonded with RMGIC versus conventional composite (CC) as secondary objective. Material and methods: A thorough literature search was done until April 2019 on various databases including Scopus, Web of Science, PubMed, Cochrane database, CINHAL, Dental and Oral Science, and manual search. Only human clinical trials and published in English language were included. We considered the experimental group of orthodontic patients with brackets bonded with RMGIC and the control group with brackets bonded with CC. Blind and induplicate study selection, data extraction, and risk of bias assessment were undertaken. RevMan software was used for data analysis. Odds ratio with 95% confidence intervals (CIs) was used to express the effect estimate of frequency of bracket failure bonded using RMGIC and CC. The risk of bias was assessed using Cochrane risk of bias tool for RCTs and ROBINS-I tool for N-RCTs. Sensitivity analyses and subgroup analysis were performed as well. Results: Out of 2285 articles, nine met the inclusion criteria. Five were RCTs and four were N-RCTs. Out of nine, seven studies were included in the meta-analysis. A random effect model was used. No significant difference was found in the bond failure rate (risk ratio: 1.48; 95% CI: 0.57–3.87; P ≤ 0.42). No difference was found in the occurrence of DWSLs between the two groups. Conclusions: Due to the limited number of studies and studies with high risk of bias, no strong conclusion can be drawn. More studies need to be done to reasonably conclude that RMGIC is beneficial in reducing the occurrence of DWSLs and have comparable bond failure rate. The protocol was registered on PROSPERO (CRD42019125386) prior to the commencement of the systematic review.