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van Zon A, van der Heijden GJ, van Dongen TM, Burton MJ, Schilder AG.van Zon A, et al. Among authors: burton mj.Cochrane Database Syst Rev. 2012 Sep 12;(9):CD009163. doi: 10.1002/14651858.CD009163.pub2.Cochrane Database Syst Rev. 2012.Update in: Cochrane Database Syst Rev. 2016 Jun 12;(6):CD009163. doi: 10.1002/14651858.CD009163.pub3PMID: 22972136Updated.Review.