Predictive factors for canine position in patients with unilateral cleft lip and palate.

Abstract

The aims were to compare cleft and non-cleft canine position, to find predictive factors for canine position and to assess surgically exposed canines. One hundred forty-eight individuals, born 1978-2005, with total unilateral cleft lip and palate (including Simonart's band <5 mm) treated in Gothenburg, were included. Canine angulation as well as vertical and horizontal position were assessed on panoramic radiographs (PAN) taken at the age of 10. Plausible predictive factors were registered from PAN, cast models and medical records. Data on spontaneous eruption or surgical exposure were available for 88 patients. Cleft- and non-cleft side was compared using paired t-test and Fisher's exact test. Multiple stepwise regression analysis and logistic regression analysis were used to detect possible predictors for cleft canine position. The cleft canine angulation was 29.3 ± 13.1 degrees (mean ± standard deviation) versus 7.6 ± 8.2 degrees on the non-cleft side (p < 0.001). Cleft canines were higher positioned and located closer to the midline compared to non-cleft canines (p < 0.001). Age for both hard palate closure and bone grafting, cleft lateral agenesis as well as transposition were associated with canine position. Cleft canines that required surgical exposure (28%) had an increased angulation and were higher positioned than spontaneously erupted canines (p < 0.001). The shortcomings were the retrospective design and incomplete assessment of the buccal-palatal canine position on 2D images. With increased age for bone grafting, decreased age for hard palate closure and transposition, an association with abnormal canine position was found. A rigorous monitoring of cleft canine eruption is, therefore, advocated.