Cirurgia ortognática: assimetria facial e a limitação do planejamento manual com articulador semi-ajustável Acon (ASA) - correção com planejamento virtual (3D) / Orthognathic surgery: facial asymmetry and the limitation of manual planning with the semi-adjustable Arcon (ASA) articulator ­ correction with virtual (3D) planning

Introdução: os casos de assimetria facial são considerados os de maior complexidade dentro do âmbito da cirurgia Buco-Maxilo-Facial, devido a alteração esquelético-morfológica nos três planos do espaço (Pitch, Yaw e Roll). Estes planos foram trazidos do posicionamento de uma aeronave no espaço para o mundo da cirurgia, mais especificamente ao planejamento virtual, para romper as limitações do planejamento manual e a plataforma de Erickson, usados durante décadas para correção não só de casos simples envolvendo movimentos puros dos ossos, como também assimetrias. Hoje é sabido que o planejamento manual ainda é usado, porém, vem caindo em desuso devido as suas limitações. A cirurgia virtual vem ganhando muito espaço e se superando a cada dia. Objetivo: relatar um caso de cirurgia ortognática em que a paciente era portadora de assimetria facial, planejada de forma manual (tradicional) e os erros encontrados após 04 anos, levando a uma re-operação baseada em planejamento virtual.

Introduction: the cases of facial asymmetry are considered the most complex within the scope of oral and maxillofacial surgery due to skeletal-morphological changes in the three planes of space (Pitch, Yaw and Roll). These plans were brought from the position of an aircraft in space to the world of surgery, specifically the virtual planning to break the limitations of manual planning and Erickson platform, used for decades to fix not only simple cases involving purê bone's movements as well as asymmetries. Today it is known that manual planning is still used, however, it has fallen into disuse because of its limitations. Virtual surgery is gaining a lot of space and surpassing every day. Objective: this article aims to report a case of orthognathic surgery in which the patient had facial asymmetry, planned manually (traditional) and the errors found after 04 years, leading to a virtual planning-based re-operation.

Fibrous Dysplasia Characterization Using Lacunarity Analysis.

Fibrous dysplasia (FD) is a developmental anomaly in which the normal medullary space of the affected bone is replaced by fibro-osseous tissue. This condition is typically encountered in adolescents and young adults. It affects the maxillofacial region and it can often cause severe deformity and asymmetry. Therefore, accurate diagnosis is critical to determine the appropriate treatment of each case. In this sense, computed tomography (CT) is a relevant resource among the imaging techniques for correct diagnosis of this condition. Thus, in this paper, we propose to analyze fibrous dysplasia through its texture pattern. To accomplish this task, we propose to use lacunarity analysis, a multiscale method for describing patterns of spatial dispersion. Results indicated lower lacunarity values for fibrous dysplasia in comparison to normal bone samples, an indication that their texture images are more homogeneous, and a high separability between the classes when using principal component analysis (PCA) and decision trees for statistical analysis.

Using a clinical protocol for orthognathic surgery and assessing a 3-dimensional virtual approach: current therapy.

Oral and maxillofacial surgeons who perform orthognathic surgery face major changes in their practices, and these challenges will increase in the near future, because the extraordinary advances in technology applied to our profession are not only amazing but are becoming the standard of care as they promote improved outcomes for our patients. Orthognathic surgery is one of the favorite areas of practicing within the scope of practice of an oral and maxillofacial surgeon. Our own practice in orthognathic surgery has completed over 1,000 surgeries of this type. Success is directly related to the consistency and capability of the surgical-orthodontic team to achieve predictable, stable results, and our hypothesis is that a successful result is directly related to the way we take our records and perform diagnosis and treatment planning following basic general principles. Now that we have the opportunity to plan and treat 3-dimensional (3D) problems with 3D technology, we should enter into this new era with appropriate standards to ensure better results, instead of simply enjoying these new tools, which will clearly show not only us but everyone what we do when we perform orthognathic surgery. Appropriate principles need to be taken into account when implementing this new technology. In other words, new technology is welcome, but we do not have to reinvent the wheel. The purpose of this article is to review the current protocol that we use for orthognathic surgery and compare it with published protocols that incorporate new 3D and virtual technology. This report also describes our approach to this new technology.

Observer reliability of three-dimensional cephalometric landmark identification on cone-beam computerized tomography.

OBJECTIVE: To evaluate reliability in 3-dimensional (3D) landmark identification using cone-beam computerized tomography (CBCT). STUDY DESIGN: Twelve presurgery CBCTs were randomly selected from 159 orthognathic surgery patients. Three observers independently repeated 3 times the identification of 30 landmarks in the sagittal, coronal, and axial slices. A mixed-effects analysis of variance model estimated the intraclass correlations (ICC) and assessed systematic bias. RESULTS: The ICC was >0.9 for 86% of intraobserver assessments and 66% of interobserver assessments. Only 1% of intraobserver and 3% of interobserver coefficients were <0.45. The systematic difference among observers was greater in X and Z than in Y dimensions, but the maximum mean difference was quite small. CONCLUSION: Overall, the intra- and interobserver reliability was excellent. Three-dimensional landmark identification using CBCT can offer consistent and reproducible data if a protocol for operator training and calibration is followed. This is particularly important for landmarks not easily specified in all 3 planes of space.