Periodontal examination in growing patients with unilateral cleft lip and palate was performed in a split-mouth study design. Higher plaque acumulation and bleeding indices were recorded for teeth on the cleft side. Pocket probing depth (PPD) and clinical attachment level (CAL) values were higher at lateral incisors and canines adjacent to the cleft. Keratinized gingiva and depth of the vestibule were lower adjacent to the cleft. This study shows that growing patients with clefts present differences regarding periodontal parameters between the cleft and the control side. These alterations affected patients' ability to maintain proper oral hygiene and resulted in differences in PPD and CAL.