New neonatal classification of unilateral cleft lip and palate-part 1: to predict primary lateral incisor agenesis and inherent tissue hypoplasia.

Objectives: To bring a neonatal classification system of unilateral cleft lip and palate (UCLP) and to correlate this classification with the distribution of the primary lateral incisor.

Design: Retrospective with longitudinal follow-up. Setting : Tertiary. Patients : One hundred twenty-one patients with treated UCLP. Thirteen plaster casts were used as controls.

Main Outcome Measures: The UCLP patients were classified anatomically into four categories: class 1 corresponds to a maxillary arch with a narrow alveolar cleft, class 2 corresponds to a balanced form, class 3 corresponds to a wide cleft and short maxilla, and class 4 corresponds to a wide cleft and long maxilla. Clinical validity was evaluated with a concordance analysis (intra- and interexaminer). This anatomical classification was also corroborated with an automatic classification determined by morphometric parameters measured on neonatal maxillary plaster casts. The class was finally correlated with the distribution of the primary lateral incisor.

Results: Clinical classification of UCLP found 12 cases of class 1 (9.9%), 36 cases of class 2 (29.8%), 47 cases of class 3 (38.8%), and 26 cases of class 4 (21.5%). The clinical classification was validated with a good intra- and interexaminer concordance analysis (κ > .6). The automatic classification was close to the clinical classification in 84%. The correlation was ideal in class 1 (100%), almost perfect in class 4 (92%), but lower for class 2 (74%) and class 3 (70%). The primary lateral incisor was usually duplicated in class 1, whereas class 2 and class 4 were correlated with a primary lateral incisor located on the lateral palatal segment. Class 3 was associated with an agenesis of the primary lateral incisor (P < .001).

Conclusions: UCLP can be classified into four different classes at birth, which can all give information about the inherent tissue hypoplasia and the distribution of the primary lateral incisor.