Effectiveness of iodoform-based filling materials in root canal treatment of deciduous teeth: a systematic review and meta-analysis

INTRODUCTION: The objective was to review the effectiveness of iodoform-based compared to noniodoform-based filling materials in the root canal treatment of deciduous teeth. METHODS: This systematic review and meta-analysis used randomized clinical trials with six months or more follow-up. The risk of bias of individual studies and the certainty of the evidence were evaluated (Cochrane risk of bias tool and GRADE, respectively). RESULTS: The initial search resulted in 5,127 studies after removal of duplicates. After screening by title and abstract, 34 full-text studies were eligible and 21 remained in the qualitative synthesis and 19 in the meta-analysis. Iodoform-based filling materials resulted in fewer clinical failures when compared to noniodoform-based filling materials at the 6 months (OR = 0.43, 95%CI: 0.19–0.97, p = .04) and 9–12 months (OR = 0.46, 95%CI: 0.23–0.93, p = .03), but not at the 18–30 months follow-up (OR = 1.08, 95%CI: 0.58–2.03, p = .81). When considering radiographic failures, there was no statistical difference between iodoform-based and noniodoform-based filling materials at the 6 months (OR = 0.72, 95%CI: 0.39–1.32, p = .29) and 18–30 months follow-ups (OR = 1.06, 95%CI: 0.51–2.21, p = .87), but fewer radiographic failures were detected at the 9–12 months follow-up (OR = 0.49, 95%CI: 0.29–0.80, p = .005). CONCLUSION: Iodoform-based filling materials showed better clinical and radiographic performance when compared to non-iodoform-based filling materials in the short term, and similar performance in the long term. However, most of the studies exhibited unclear or high risk of bias and the overall certainty of the evidence ranged from low to very low. Therefore, new randomized clinical trials must be accomplished to corroborate this conclusion.