Scandcleft randomized trials of primary surgery for unilateral cleft lip and palate: comparison of dental arch relationships and dental indices at 5, 8, and 10 years

Abstract

Background and trial design: The Scandcleft intercentre study evaluates the outcomes of four surgical protocols (common method Arm A, and methods B, C, and D) for treatment of children with unilateral cleft lip and palate (UCLP) in a set of three randomized trials of primary surgery (Trials 1, 2, and 3).

Objectives: To evaluate and compare dental arch relationships of 5-, 8-, and 10-year-old children with UCLP after four different protocols of primary surgery and to compare three dental indices. The results are secondary outcomes of the overall trial.

Methods: Study models taken at the ages of 5 (n = 418), 8 (n = 411), and 10 years (n = 410) were analysed by a blinded panel of orthodontists using the Eurocran index, the 5-year-olds' (5YO) index, and the GOSLON Yardstick. Student's t-test, Pearson's correlation, chi-square test, and kappa statistics were used in statistical analyses.

Results: The reliability of the dental indices varied between moderate and very good, and those of the Eurocran palatal index varied between fair and very good. Significant correlations existed between the dental indices at all ages. No differences were found in the mean 5-, 8-, and 10-year index scores or their distributions within surgical trials. Comparisons between trials detected significantly better mean index scores in Trial 2 Arm C (at all ages) and in Trial 1 Arm B (at 5 and 10 years of age) than in Trial 3 Arm D. The mean Eurocran dental index scores of the total material at 5, 8, and 10 years of age were 2.50, 2.60, and 2.26, and those of the 5YO index and GOSLON Yardstick were 2.77, 2.90, and 2.54, respectively. At age 10 years, 75.8% of the patients had had orthodontic treatment.

Conclusions: The results of these three trials do not provide evidence that one surgical method is superior to the others. The reliabilities of the dental indices were acceptable, and significant correlations existed between the indices at all ages. The reliability of the Eurocran palatal index was questionable.

Trial registration: ISRCTN29932826.

Figure 1.

Flow charts of the three Scandcleft trials.

Figure 1.

Flow charts of the three Scandcleft trials.

Figure 1.

Flow charts of the three Scandcleft trials.

Figure 2.

Sequence of closure of unilateral cleft lip and palate (UCLP). The figure and text are reprinted with permission from Rautio et al. (2017), Journal of Plastic Surgery and Hand Surgery, Taylor & Francis. The first operation is indicated by the red line and the second operation by the blue line. In the common method (Arm A), the lip was repaired simultaneously with soft palate closure at 3–4 months, followed by hard palate closure at 12 months. In Trial 1, the common method (Arm A) was compared with hard palate closure delayed until 3 years of age (Arm B). In Trial 2, the common method (Arm A) was compared with closure of the lip at 3–4 months, followed by closure of the hard and soft palate together at 12 months (Arm C). In Trial 3, the common method (Arm A) was compared with lip and hard palate closure at 3–4 months, followed by soft palate closure at 12 months (Arm D).

Figure 3.

Photographs of examples of the models used for reference of palatal morphology of the Eurocran index scores from grade 1 to 3. Palatal morphology according to the Eurocran index (12). 1. Good anterior and posterior height; minor surface irregularities (bumps and crevices); no or minor deviation of arch form. 2. Moderate anterior and posterior height; moderate surface irregularities (bumps and crevices); moderate deviation of arch form (e.g. segmental displacement). 3. Severe reduction in palate height; severe surface irregularities (bumps and crevices); severe deviation in arch form (e.g. ‘hourglass’ constriction). The worst feature of the three suggests the initial score. This may be modified up or down depending on how good the other features are. If good arch form was achieved by means of orthodontic treatment, the case is graded lower.

Figure 4.

Proportions (%) of the mean dental index score distributions of the total sample at 5, 8, and 10 years of age.