Two-dimensional vs three-dimensional assessment of soft tissue facial prifile : a non invasive study in healthy 6-year-old children

AIM: In medical practice, the analysis of facial soft tissues often complement (or even supplement) the evaluation of the hard-tissue relationships. Current technology provides reference data in three dimensions, but clinical practice still uses two-dimensional photographs. In the current study, two-dimensional photographic and computerized, three-dimensional angles measured on the facial profile of children were compared. METHODS: Two-dimensional angular measurements (facial convexity including/excluding the nose; maxillary prominence; nasal prominence; nasolabial; mentolabial; maxillo-labio-mandibular; interlabial) were obtained on the facial profile photographs of 55 boys and 31 girls aged 6; measurements were compared to three-dimensional computerized data collected on 27 boys and 28 girls of the same age and ethnic group. RESULTS: On average, in boys, only the angles of facial convexity including the nose, interlabial, nasolabial and maxillo-labio-mandibular showed differences between the means larger than 2 degrees (up to 2.5 degrees). Statistically significant differences (P<0.05, Watson-Williams' test) were found for the angle of facial convexity including the nose and the maxillary prominence angle. In girls, differences between the two methods larger than 2 degrees were found for the interlabial, maxillo-labio-mandibular (statistically significant), and mentolabial angles (differences up to 7 degrees, corresponding to 4% of the relevant mean). CONCLUSION: The two-dimensional photographic and the three-dimensional computerized data compared in the current study, even not superimposable, seemed sufficiently interchangeable, at least from a clinical point of view. A particular attention should be given to the recording of lip position.