Ana Luiza Meneguci Moreira Franco

Purpose: This study evaluates the reliability of three-dimensional (3D) facial measurements obtained from different acquisition technologies. Specifically, it investigates whether low-cost smartphone-based photogrammetry and videogrammetry can produce measurements comparable to those derived from structured light scanning, and identifies sources of variability associated with each modality. Methods: Fifteen participants were imaged using three techniques: structured light scanning, smartphone photogrammetry, and smartphone videogrammetry. Inter-landmark distances were computed for each resulting 3D model, including both stable anatomical landmarks and those prone to placement difficulty. A statistical workflow was applied, incorporating non-parametric hypothesis testing, iterative outlier detection, and normality assessments to evaluate measurement variability attributable to acquisition modality, subject movement, and landmark uncertainty. Results: The three acquisition modalities produced broadly comparable inter-landmark measurements, indicating no substantial loss of accuracy when using smartphone-based methods. However, increased variability was observed in anatomically complex regions, particularly the perioral area, as well as in landmarks known to be difficult to localize. These discrepancies persisted across all modalities, including structured light scanning. Conclusions: Smartphone-based photogrammetry and videogrammetry represent viable, low-cost alternatives to structured light scanning for 3D facial measurement. Nonetheless, landmark-specific uncertainty remains a critical factor, particularly in challenging anatomical regions. The findings highlight the importance of considering both acquisition modality and landmark reliability in the design and reporting of facial anthropometric studies.

As fendas orofaciais (FO) são anomalias congênitas que impactam o desenvolvimento infantil. Realizamos a análise ecológica-espacial e traçamos o perfil epidemiológico materno-infantil dos nascidos vivos (NV) com FO no Rio de Janeiro, por regiões de saúde, com dados do SINASC (2014–2023). A prevalência média de FO variou de 3,5 a 6,7 por 10.000 NV. Baía da Ilha Grande, Serrana e Noroeste apresentaram maiores prevalências, abaixo das estimativas nacionais e globais, sugerindo subnotificação. Houve maior frequência em prematuros, no sexo masculino e com baixos escores de Apgar. 23,3% dos casos estavam associados a outras anomalias, principalmente musculoesqueléticas.

Facial asymmetry presents a significant challenge for health practitioners, including physicians, dentists, and physical therapists. Manual measurements often lack the precision needed for accurate assessments, highlighting the appeal of imaging technologies like structured light scanners and photogrammetric systems. However, high-end commercial systems remain cost prohibitive, especially for public health services in developing countries. This study aims to evaluate cell-phone-based photogrammetric methods for generating 3D facial models to detect facial asymmetries. For this purpose, 15 patients had their faces scanned with the ACADEMIA 50 3D scanner, as well as with cell phone images and videos using photogrammetry and videogrammetry, resulting in 3D facial models. Each 3D model (coming from a 3D scanner, photogrammetry, and videogrammetry) was half-mirrored to analyze dissimilarities between the two ideally symmetric face sides using Hausdorff distances between the two half-meshes. These distances were statistically analyzed through various measures and hypothesis tests. The results indicate that, in most cases, both photogrammetric and videogrammetric approaches are as reliable as 3D scanning for detecting facial asymmetries. The benefits and limitations of using images, videos, and 3D scanning are also presented.

Objetivo Analisar a distribuição dos casos e a tendência temporal de fendas orofaciais (fenda palatina, fenda labial e fenda labial com fenda palatina) no Brasil, segundo regiões e unidades da Federação, nos últimos 12 anos, além de comparar proporções durante a pandemia de covid-19, de 2020 a 2021, com a série histórica anterior, de 2010 a 2019.

Objective To analyze distribution of orofacial cleft cases (cleft palate, cleft lip and cleft palate with cleft lip) and their temporal trend in Brazil, according to the country’s regions and Federative Units from 2010 to 2021, in addition to comparing proportions during the COVID-19 pandemic, from 2020 to 2021, with the preceding time series, from 2010 to 2019.