Accuracy of three-dimensional virtual simulation of the soft tissues of the face in OrtogOnBlender for correction of class II dentofacial deformities: an uncontrolled experimental case-series study

Abstract

Purpose To assess whether virtual simulations of the projection of the soft tissues of the face after class II bimaxillary orthognathic surgery, generated from 3D reconstruction of preoperative computed tomography (CT) scans, differed significantly from the actual soft tissue profile obtained in the late postoperative period (beyond 6 months). Secondarily, to validate the accuracy of a free, open-source software suite for virtual soft tissue planning in orthognathic surgery. Methods Helical CT scans were obtained pre- and postoperatively from 16 patients with Angle class II malocclusion who underwent bimaxillary orthognathic surgery. A comparative study between soft tissue meshes constructed for surgical simulation (M1) and the actual meshes obtained from postoperative scans (M2) was then performed. To establish the accuracy of 3D facial soft tissue simulation in a free and open-source software suite (OrtogOnBlender-OOB), 17 predetermined anatomic landmarks were measured in M1 and M2 scans after alignment of cranial structures. Results The mean error between preoperative simulations and actual postoperative findings was < 2 mm for all anthropometric landmarks. The overall average error for the facial soft tissues was 1.07 mm. Conclusion Comparison between preoperative simulation (M1) and actual postoperative findings (M2) showed clinically relevant ability of the method to reproduce actual surgical movement reliably (< 2-mm error). OOB is capable of accurate soft tissue planning for orthognathic surgery, but mesh deformation methods still require improvement. Trial registration RBR-88jff9 . Retrospectively registered at Brazilian Registry of Clinical trials-ReBec ( http://www.ensaiosclinicos.gov.br ) May 06, 2020.

The Facial Reconstruction of a Mesolithic Dog, Muge, Portugal

“…In addition to its usefulness to archaeology, the anatomical deformation technique was also applied in the veterinary medicine field for the manufacture of beaks' prostheses for species of toucan (IE Staff, 2016) [28], goose (Dormehl, 2016) [29], macaw parrot (Hooper, 2016) [30], crow (Duncombe, 2017) [31] and tortoise shell (Thorbecke, 2016) [32], which demand high anatomical rigor. Human medicine (e.g., surgical planning) has also benefited (Façanha de Carvalho et al, 2021) [33], since the anatomical deformation allowed for the adjustment of prostheses using virtual donors or even mirroring healthy parts of the face (cogitas3d, 2016 [34]; Cunha et al, 2020 [35]; Gamarra et al, 2019 [36]; Salazar-Gamarra, 2020) [37]. It is an approach based on real structures and deformations that maintain anatomical proportions.…”

A quantitative analysis of facial changes after orthodontic treatment with vertical control in patients with idiopathic condylar resorption

“…33 Likewise, assisted by TAD, an average of 2.03 mm intrusion of the upper first molar and 1.57° counterclockwise rotation of the mandibular plane were achieved by Oliveira et al 9 Similarly, Kuroda et al 34 With 3DMM, the change in the nose-lip-chin relationship can be intuitively and accurately demonstrated. By using 2 mm as the threshold for clinical significance, 22 an elliptical area marked by supralabial, soft tissue pogonion, and both chelion points was observed. The largest retrusion of the lips was at the lower vermilion (5.00 mm), which was supported by previous studies.…”

“…Moreover, 3D facial heatmaps were used for the visualization of the study findings 21 . The changes in the facial area that were larger than 2 mm were assumed to have clinical significance and were also marked 22 . Moreover, the upper lip (the area marked by left/right Chelion, Stomion Superius, and Subnasale), lower lip (the area marked by left/right Chelion, Stomion Superius, and Sublabial), and chin (the area marked by the perpendicular line passing through left/right Chelion, Soft Tissue Menton, and Sublabial) were extracted and displayed separately via heatmaps.…”

Orthognathic Surgical Treatment and Its Effect on Soft Tissues

“…Dijitalleşen dünyada, ameliyat öncesinde, hastaların ameliyat sonrasındaki muhtemel yeni yüz görünüşleri ile fikir sahibi olmak istemeleri, hastaların beklentilerinin ne kadar karşılanacağı ile hekimlerin bir fikir sahibi olmalarına yardımcı olabilen öngörü uygulamaları ayrıca hekim hasta fikir alışverişinde bulunarak tedaviyi en başarılı şekilde sonuçlandıracak en uygun tedavi yolunu seçmesi, hastanın anlayabilirliğini artırmak ve tedavi önerilerinin kabul edilebilirliğini sağlamak açısından da oldukça önemlidir 42,43 . Bu sebeplerle 20 yıldan fazla bir süredir, araştırmacılar ortognatik cerrahide yumuşak doku hareketlerini simüle etmek için bilgisayar yazılımı geliştirmekte ve yüzün stereofotogrametri ve lazer tarayıcılar gibi 3 boyutlu tarayıcılar yardımı ile görüntülerini kaydetmektedirler 44 .…”

“…2020 yılında Cunha ve ark. 'ı tarafından çift çene ortognatik cerrahi ile tedavi edilen 16 iskeletsel Sınıf II hasta üzerinde yapılan çalışmanın sonuçlarına göre, ameliyattan önce ve sonra ölçülen 17 anatomik landmark'ın simülasyon programındaki (OrtogOnBlender-OOB) ve gerçek ölçümleri arasındaki genel hata ortalaması 1.07 mm olarak tespit edilmiştir ve klinik olarak ilgili programın güvenli bir şekilde kullanılabileceği rapor edilmiştir 44 .…”