The purpose of this study was to identify factors affecting Migrant Head Start (MHS) children's dental health. Enrollment duration (number of years and weeks enrolled) and individual and family factors were considered. Children (N = 931) who enrolled in Michigan Migrant Head Start during 2012-2013 were selected for the study sample and classified by years of enrollment: those who enrolled for one year, two years, or three or more years. Children's dental outcomes were measured on identified dental problems and follow-up dental treatment. Logistic regression analyses were conducted to examine whether enrollment duration was associated with dental health in addition to individual and family characteristics. Children who spent more time in the program were more likely to have their dental problems identified and to receive follow-up dental treatment. Children's special needs status, ethnicity, welfare receipt, transportation, health insurance status at enrollment, and other health treatment statuses were associated with dental health outcomes. Findings suggest that MHS should consider various individual, family, and Head Start enrollment factors in promoting dental health.