Assessment of facial and cranial symmetry in infants with deformational plagiocephaly undergoing molding helmet therapy

Abstract

Objectives: The aim of this study was to determine the effects on facial and cranial symmetry through molding helmet therapy in infants with positional plagiocephaly. A 3D asymmetry index (3DAI), which measures both cranial and facial symmetry, was introduced and compared to the Cranial Vault Asymmetry Index (CVAI).

Material & methods: Optical 3D-scans of children with positional plagiocephaly were evaluated retrospectively. Pre- and post-therapeutic asymmetry values of the cranium and face were determined and paired t-tests were applied. Pearson correlations were calculated for facial and cranial asymmetries.

Results: 65 children (age: 3-6 months) were included. Asymmetry values (mean/standard deviation, pre- and post-therapeutic) were for 3DAI determinations: cranium: 9.96/1.84-8.11/1.74 p < 0.001; face: 4.70/1.06-3.89/0.91 p < 0.001; and for CVAI measurements: 9.10/3.29-5.88/2.78 p < 0.001. No correlation was found between facial and cranial asymmetry (p > 0.05).

Conclusion: Symmetry values improved significantly in post therapeutic 3D-scans for both asymmetry indices. The analysis of cranial symmetry by 3DAI should be preferred over the CVAI because it gives more comprehensive information, including the symmetry of the entire cranial surface and the face.

Keywords: 3D imaging; Cranial deformation; Molding helmet therapy; Positional plagiocephaly; Symmetry.