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Bretz WA, Eklund SA, Radicchi R, Schork MA, Schork N, Schottenfeld D, Lopatin DE, Loesche WJ.Bretz WA, et al.J Public Health Dent. 1993 Fall;53(4):235-40. doi: 10.1111/j.1752-7325.1993.tb02710.x.J Public Health Dent. 1993.PMID: 8258786Free article.