Heterogeneity of studies
Variables List
Different study designs Retrospective [36,44], prospective [32,34], randomised [58,64].
Different overall aims Assessment of the molding of the nasal cartilage [27,44], molding of the alveolar possesses [40,42].
Mixed criteria for evaluating results Landmarks on casts [26], cephalometry, facial photographs [43,44], photographs on cast [45,46],
three-dimensional optical scanner on the cast [64], three-dimensional optical facial scanner [62,63].
Inadequate sample sizes Small sample size [17,19], without control group [27].
Inconsistent follow-up period Before the primary surgery (during the first 18 months), after the primary surgeries [22,23,26].
Heterogeneity of appliances Hotz plate [41,43], Grayson NAM [40].
Variable age of the patient When the appliance was used, when primary surgeries were performed.
Mixed level of surgeon experience [12]

NAM = nasoalveolar molding.