ObjectivePatients with a cleft require structured procedures to achieve feasible treatment results. Since many treatment protocols coexist without being superior to one another, this study investigated the Saarland University Hospital treatment concept for patients with unilateral and bilateral clefts to evaluate its effects upon dental arch dimensions until the early mixed dentition.Material and methodsDigitized plaster models were used for data collection. Records of 83 patients (Cleft n = 41 [UCLP n = 28, BCLP n = 13], Non-Cleft Control n = 42) comprised 249 casts. The evaluation included established procedures for measurements of edentulous and dentate jaws. Statistics included Shapiro–Wilk, Friedmann, Wilcoxon and Mann–Whitney-U-Tests for the casts. The level of significance was set at p < 0.05.ResultsThe cast analysis showed an approximation of arch dimensions towards those of age-matched patients without a cleft until early mixed dentition. The mean values of patients with and without cleft lip and palate were almost indistinguishable when compared in primary and/or early mixed dentition.ConclusionsThe evaluated treatment concept leads to feasible outcomes regarding dental arches in patients with unilateral and bilateral clefts compared to an age-matched non-cleft control.Clinical relevanceThe evaluated treatment concept leads to favorable outcomes until early mixed dentition.