Objective: To evaluate the efficiency of molar distalization associated with the second and third molar eruption stage.
Materials and methods: A systematic computerized database search was conducted using several databases. Adaptations of the terms molar distalization and distalizing appliances were used. The reference lists of all the selected articles were also searched for any potential articles that might have been missed in the electronic search. The data provided in the selected publications were grouped and analyzed in terms of molar distalization with respect to various eruption stages of maxillary second and third molars.
Results: Out of the 13 initially identified articles only four fulfilled the final selection criteria. Three of the four studies showed no statistical significance in linear molar distalization based on the eruptive stage of the second and/or third molars, while one study found that the amount of distal movement of the first molars was significantly greater in the group with unerupted second molars. Only one study found that the amount of molar tipping that occurred as a result of distalization was related to the eruption stage of the maxillary molars. Similarly, three of the four studies found that molar distalization time was not significantly affected by eruption of the second or third molars.
Conclusion: The effect of maxillary second and third molar eruption stage on molar distalization-both linear and angular distalization-appears to be minimal. This conclusion is only based on low-level of evidence clinical trials. The large variability in the outcomes should be considered clinically.