BACKGROUND: Long-term health of the stomatognathic system, as well as esthetics, is the therapeutic goal in patients with facial clefts. The aim of this study was to analyze the periodontal situation of patients with cleft palate (CP) and cleft lip, palate, and alveolus (CLPA) to elicit the differing degrees and localization of periodontal disease. METHODS: In 30 patients with unilateral cleft lip, palate, and alveolus (UCLPA), 30 patients with cleft palate (CP), and 20 patients with bilateral cleft lip, palate, and alveolus (BCLPA), the gingival situation was identified and classified according to the sulcus bleeding index (SBI). Periodontal attachment loss and pathological loosening of teeth were noted for identification of periodontal lesions. The state of oral hygiene was recorded by the approximal plaque index (API). RESULTS: In general, poor oral hygiene was found in all patients. The SBI showed a high incidence of gingivitis in patients with cleft lip, palate, and alveolus. Patients with cleft palate had a minor extent of sulcus bleeding. Periodontal disease was found to a similar extent to that in the general population in patients with cleft palate, whereas patients with cleft lip, palate, and alveolus had a predisposition to deep periodontal destruction of teeth adjacent to the cleft. The registration of pathological loosening of teeth, a result of attachment loss, corresponded to the degree of periodontal disease shown by the attachment loss. CONCLUSIONS: A critical periodontal situation was found in patients with unilateral and bilateral cleft lip, palate, and alveolus, ultimately leading to tooth loss in the front tooth region. In contrast, patients with cleft palate exhibited periodontal situations similar to that found in the general population with additional damage, which may be attributed to orthodontic treatment.