Relation of maxillary permanent central incisor rotations with the primary palatal margin and overjet in repaired complete unilateral cleft lip and palate.

Objectives: To examine the relation of maxillary permanent central incisor rotation with the primary palatal margin (PPM) and overjet in the mixed dentition in complete unilateral cleft lip and palate (cUCLP).

Materials and methods: Dental casts and preorthodontic records taken before alveolar bone grafting were examined to exclude patients having permanent teeth distal to the cleft side maxillary central incisor (CS1) and mesial to the cleft. Maxillary central incisor rotation, the angle between PPM and midline, proximity of the lingual surface of the central incisor to PPM, and overjet were measured from standardized occlusal photographs of the dental casts of 54 children with repaired cUCLP (38 M, 16 F; aged 8.7 ± 1.0 years). Descriptive analysis and correlation statistics were performed.

Results: Rotations were noted in 92.6% of the CS1. Their magnitude (111.2 ± 24.2°) was significantly greater than the noncleft side maxillary central incisor (NCS1) rotations (76.7 ± 15.7°). Rotations were predominantly distolabial for the CS1 and distopalatal for the NCS1. The PPM was located within 2 mm of the lingual surface of the CS1 in 35.2% of the sample. Severe CS1 rotation existed in 48.2% of the sample and was significantly correlated with the PPM angle (r = 0.3; P = .046) and when its proximity to the PPM was within 2 mm (φ = 0.3; P = .028). Overjet was not significantly correlated with the magnitude of rotation.

Conclusions: The angle between PPM and the midline and its proximity to CS1 are associated with the severity of CS1 rotation in repaired cUCLP. Orthodontic implications are discussed.