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The 3D prediction of post-operative changes is an inevitable tool for the surgical correction of facial asymmetry. The objective is to execute an evidence-based review answering the following question. Does the 3D virtual prediction planning draw reliable and accurate results in the surgical outcome related to the soft tissues of the face in facial asymmetry? This systematic review of the literature is based on the 3D soft tissue prediction planning of facial asymmetry correction to draw conclusions on the reliability and accuracy of these methods in the surgical outcome related to the soft tissues of the face. PubMed, Web of Science, Cochrane, and Ovid databases were adopted for the literature search. Studies published between years 2000 and 2020, aimed at the assessment of soft tissue predictions using software prediction packages for facial asymmetry, were selected. The Preferred Reporting Items for Systematic Reviews and Meta-analysis (PRISMA) was applied. Quadas-2 tool was used for the qualitative evaluation of selected studies. Initial search yielded 248 articles. Twenty articles fulfilled the inclusion and exclusion criteria and selected for qualitative analysis. Finally, 12 articles were selected for quantitative analysis. The results indicate 3D imaging prediction methods provided more accurate information with less distortion for soft tissue prediction regardless of various softwares currently available. The prediction of soft tissue accuracy in facial asymmetry was less accurate in lower face regardless of the type of surgery for facial asymmetry. The mean prediction error was less than 2 mm. [ABSTRACT FROM AUTHOR]

Using a computer-aided, three-dimensional surgical simulation planning program, soft-tissue planning can help achieve adequate facial esthetics and patient satisfaction after orthognathic surgery. This study aimed to assess the Simplant O&O software's soft tissue prediction accuracy. Fourteen skeletal type III patients who underwent orthognathic surgery by the same surgeons were included in this prospective study, and they were separated into two groups: the one-jaw (n = 5) and two-jaw (n = 9) groups. The software was used to analyze the preoperative (T0) and 4-month postoperative computed tomography data (T1), as well as intraoral scans. Data from cone-beam computed tomography and stereolithography from a scanned dental cast were used to reconstruct a composite skull model. Based on the presurgical CT data, the program generated a predicted soft tissue image (TP), which was then superimposed on the T1. The distances between seven T1 and TP landmarks were measured and evaluated using a one-sample t-test. In the one-jaw group, the mean error for all linear measurements was 1.73 ± 1.14 mm, whereas the mean error of the two-jaw group was 1.03 ± 0.83 mm, and both measurements were within clinically acceptable limits. Pronasele had the best correlation (mean error of 0.63 ± 0.45 mm) while soft tissue pogonion and soft tissue point B had the worst correlations (mean error of 2.87 ± 2.22 mm and 1.31 ± 0.98 mm, respectively). Even though there were some limitations, it was possible to conclude that the ability to accurately predict soft tissue changes using Simplant O&O for skeletal type III patients makes it adequate for use in clinical practice. [ABSTRACT FROM AUTHOR]

Using a computer-aided, three-dimensional surgical simulation planning program, soft-tissue planning can help achieve adequate facial esthetics and patient satisfaction after orthognathic surgery. This study aimed to assess the Simplant O&O software’s soft tissue prediction accuracy. Fourteen skeletal type III patients who underwent orthognathic surgery by the same surgeons were included in this prospective study, and they were separated into two groups: the one-jaw (n = 5) and two-jaw (n = 9) groups. The software was used to analyze the preoperative (T0) and 4-month postoperative computed tomography data (T1), as well as intraoral scans. Data from cone-beam computed tomography and stereolithography from a scanned dental cast were used to reconstruct a composite skull model. Based on the presurgical CT data, the program generated a predicted soft tissue image (TP), which was then superimposed on the T1. The distances between seven T1 and TP landmarks were measured and evaluated using a one-sample t-test. In the one-jaw group, the mean error for all linear measurements was 1.73 ± 1.14 mm, whereas the mean error of the two-jaw group was 1.03 ± 0.83 mm, and both measurements were within clinically acceptable limits. Pronasele had the best correlation (mean error of 0.63 ± 0.45 mm) while soft tissue pogonion and soft tissue point B had the worst correlations (mean error of 2.87 ± 2.22 mm and 1.31 ± 0.98 mm, respectively). Even though there were some limitations, it was possible to conclude that the ability to accurately predict soft tissue changes using Simplant O&O for skeletal type III patients makes it adequate for use in clinical practice.

Featured Application: Endodontics. The instrumental fracture is a common endodontic complication that is treated by surgical or non-surgical removal approaches. However, no tool exists to help the clinician to choose between available strategies, and decision-making is mostly based on clinical judgment. Digital solutions, such as Finite Element Analysis (FEA) and Virtual Treatment Planning (VTP), were recently proposed in maxillofacial surgery. The aim of the current study is to present a digital tool to help decide between non-surgical and surgical strategies in a clinical situation of a fractured instrument. Five models have been created: the initial state of the patient, two non-surgical removal strategies using a low or high root canal enlargement, and two surgical removal strategies using a 3- or 6-mm apicoectomy. Results of the VTP found a risk of perforation for the non-surgical strategies and sinus proximity for surgical ones. FEA showed the lowest mechanical risk for the apicoectomy strategy. A 3-mm apicoectomy approach was finally chosen and performed. In conclusion, this digital approach could offer a promising decision support for instrument removal by planning the treatment and predicting the mechanical impact of each strategy, but further investigations are required to confirm its relevance in endodontic practice. [ABSTRACT FROM AUTHOR]

Purpose: While novel tools for segmentation of the mitral valve are often based on automatic image processing, they mostly require manual interaction by a proficient user. Those segmentations are essential for numerical support of mitral valve treatment using computational fluid dynamics, where the reconstructed geometry is incorporated into a simulation domain. To quantify the uncertainty and reliability of hemodynamic simulations, it is crucial to examine the influence of user-dependent variability in valve segmentation. Methods: Previously, the inter-user variability of landmarks in mitral valve segmentation was investigated. Here, the inter-user variability of geometric parameters of the mitral valve, projected orifice area (OA) and projected annulus area (AA), is investigated for 10 mitral valve geometries, each segmented by three users. Furthermore, the propagation of those variations into numerically calculated hemodynamics, i.e., the blood flow velocity, was investigated. Results: Among the three geometric valve parameters, AA was least user-dependent. Almost all deviations to the mean were below 10%. Larger variations were observed for OA. Variations observed for the numerically calculated hemodynamics were in the same order of magnitude as those of geometric parameters. No correlation between variation of geometric parameters and variation of calculated hemodynamic parameters was found. Conclusion: Errors introduced due to the user-dependency were of the same size as the variations of calculated hemodynamics. The variation was thereby of the same scale as deviations in clinical measurements of blood flow velocity using Doppler echocardiography. Since no correlation between geometric and hemodynamic uncertainty was found, further investigation of the complex relationship between anatomy, leaflet shape and flow is necessary. [ABSTRACT FROM AUTHOR]

The instrumental fracture is a common endodontic complication that is treated by surgical or non-surgical removal approaches. However, no tool exists to help the clinician to choose between available strategies, and decision-making is mostly based on clinical judgment. Digital solutions, such as Finite Element Analysis (FEA) and Virtual Treatment Planning (VTP), were recently proposed in maxillofacial surgery. The aim of the current study is to present a digital tool to help decide between non-surgical and surgical strategies in a clinical situation of a fractured instrument. Five models have been created: the initial state of the patient, two non-surgical removal strategies using a low or high root canal enlargement, and two surgical removal strategies using a 3- or 6-mm apicoectomy. Results of the VTP found a risk of perforation for the non-surgical strategies and sinus proximity for surgical ones. FEA showed the lowest mechanical risk for the apicoectomy strategy. A 3-mm apicoectomy approach was finally chosen and performed. In conclusion, this digital approach could offer a promising decision support for instrument removal by planning the treatment and predicting the mechanical impact of each strategy, but further investigations are required to confirm its relevance in endodontic practice.

Purpose: Severe mitral valve regurgitation can either be treated by a replacement or a repair of the valve. The latter is recommended due to lower perioperative mortality and better long-term survival. On the other hand, recurrence rates after mitral valve repair are high compared to those after replacements and the repair intervention can cause induced mitral valve stenosis. So far, there are no methods to predict the hemodynamic outcome of a chosen treatment or to compare different treatment options in advance. To overcome this, diastolic mitral valve hemodynamics are simulated using computational fluid dynamics after different virtual treatments of the valve.Methods: The left ventricular geometry of one patient was reconstructed using trans-esophageal echocardiography and computed tomography data. Pre-op hemodynamics are simulated using a referenced wall model to avoid expansive modeling of wall motion. Subsequently, the flow structures are compared to in vivo measurements. After manipulating the patient-specific geometry in order to mimic a restrictive mitral annuloplasty as well as a MitraClip intervention, hemodynamics results are calculated.Results: Good agreements exist between calculated pre-op hemodynamics and in vivo measurements. The virtual annuloplasty did not result in any remarkable change of hemodynamics. Neither the pressure drop nor the velocity field showed strong differences. In contrast, the virtual MitraClip intervention led to a complete change in blood flow structures as well as an elevated pressure drop across the valve.Conclusion: The presented approach allows fast simulation of the diastolic hemodynamic situation before and after treatment of a mitral valve insufficiency. However, this approach is limited to the early diastolic phase of the cardiac cycle and needs to be validated using a larger sample size. [ABSTRACT FROM AUTHOR]

Advances in precision medicine portend similar progress in orthodontics and will be increasingly harnessed to achieve customized treatment approaches and enhance treatment efficiencies. Our goal is to provide a background on emerging advances in computer technologies and biomedicine and highlight their current and likely future applications to precision orthodontics. A review of orthodontically relevant technologies and advances in pertinent biological research was undertaken. Innovations in computer hardware and software, and 3D imaging technologies offer the ability for customized treatment and biomechanical planning that will be more fully realized within the next few decades. These technologies combined with 3D printing are already being applied to customized appliance fabrication such as aligners and retainers. The future prospects for custom fabrication of orthodontic brackets of appropriate material properties and smart devices are highly desirable and compelling goals. Within biomedicine, the fundamental understanding of cartilage growth and bone biology is currently being tested in animal models to modify mandibular growth and modulate tooth movement, respectively. Some of these discoveries will ultimately have clinical applications in orthodontics including for growth modification, accelerating orthodontic tooth movement, and enhancing anchorage or retention of teeth. Additional genomic and proteomic information will add to further customization of orthodontic diagnosis and treatments. Over the coming decades, precision orthodontics will continue to benefit from advances in many fields and will require the integration of advances in technology, and biomedical and clinical research to deliver optimal, efficient, safe, and reproducible personalized orthodontic treatment. [ABSTRACT FROM AUTHOR]

Three-dimensional (3D) soft tissue prediction is replacing two-dimensional analysis in planning for orthognathic surgery. The accuracy of different computational models to predict soft tissue changes in 3D, however, is unclear. A retrospective pilot study was implemented to assess the accuracy of Dolphin 3D software in making these predictions. Seven patients who had a single-segment Le Fort I osteotomy and had preoperative (T 0 ) and >6-month postoperative (T 1 ) cone beam computed tomography (CBCT) scans and 3D photographs were included. The actual skeletal change was determined by subtracting the T 0 from the T 1 CBCT. 3D photographs were overlaid onto the T 0 CBCT and virtual skeletal movements equivalent to the achieved repositioning were applied using Dolphin 3D planner. A 3D soft tissue prediction (T P ) was generated and differences between the T P and T 1 images (error) were measured at 14 points and at the nasolabial angle. A mean linear prediction error of 2.91 ± 2.16 mm was found. The mean error at the nasolabial angle was 8.1 ± 5.6°. In conclusion, the ability to accurately predict 3D soft tissue changes after Le Fort I osteotomy using Dolphin 3D software is limited. [ABSTRACT FROM AUTHOR]

Abstract: We describe our experience with various silicone materials for making one-step and two-step impressions of the cleft-lip-palate-nose complex during nasoalveolar moulding. Our technique is superior to common alginate-based impression techniques, as it provides precise reproduction of the complex anatomy of the cleft, and is compatible with the latest available methods of planning treatment with nasoalveolar moulding, such as computer-aided reverse engineering and rapid prototyping. [Copyright &y& Elsevier]

This study aimed to investigate the factors that could be associated with the risk of labial cortical bone wall perforation with immediate implant placement (IIP) in the maxillary aesthetic zone, in a cone-beam computed tomography (CBCT) virtual study. CBCT exams from 126 qualified subjects (756 teeth) were included. Implants were virtually positioned in two different positions: in the long axis of the tooth (prosthetically-driven position) and in an ideal position in relation to adjacent anatomical structures (bone-driven position). Two different implant diameters were planned for each tooth position, namely, 3.75 and 4.3 mm for central incisors and canines, and 3.0 and 3.3 mm for lateral incisors. The incidence of perforation was nearly 80% and 5% for prosthetically- and bone-driven position, respectively. Factors associated with a higher risk of cortical bone wall perforation (bone-driven position), according to logistic regression analysis, were women, wider implants, Sagittal Root Position class IV, and decrease of the labial concavity angle. Perforation of the labial cortical bone wall can be greatly minimized when the implant is placed in a bone-driven position compared to a prosthetically-driven position. It is important to preoperatively evaluate the morphological features of the implant site for risk assessment and to individualize the treatment plan.

Introduction: This article aims at describing the four-year outcome of a surgical procedure implanting a patient specific epithesis system in two patients., Technical Note: After virtual 3D reconstruction of the anatomy and mirroring of the healthy ear, the position of the three Locator ® attachments were optimized in the software to embed them as accurately as possible in the planned episthesis antihelix. The personalized plate bearing the three Locator ® implants was then manufactured. Ten osteosynthesis screws were placed around the abutments to ensure bone anchorage. Post-operative antibiotic therapy was prescribed for the duration of ten days. The episthesis was placed two months post-operatively. The follow-up for each patient was 65 and 57 months respectively with no complications to report., Conclusion: 3D planning assists the surgeon and eliminates several constraints related to the placement of bone implants. It assists the surgical procedure and improves both the aesthetics and functional result of the surgery., (Copyright © 2018 Elsevier Masson SAS. All rights reserved.)

Introduction: Cutting and drilling guides manufactured using computer-aided design/computer-aided manufacturing (CAD/CAM) technologies have attracted increasing interest in orthognathic surgery, particularly in complex cases. The development of these guides requires virtual surgery planning and three-dimensional modelling before they can be printed in titanium, polyamide or resin. We report the use of a personalized titanium device to assist bilateral sagittal split osteotomy (BSSO) with or without genioplasty combined with individual implants for repositioning and fixation. This one-piece guide for both sides of the BSSO allows the initiation of cutting and drilling with less invasive drill placement and greater accuracy., Procedure: The titanium guide was manufactured using CAD/CAM technologies after conventional digital planning of BSSO. Intraoperatively, the guide was fitted on each side of the mandibular occlusal surface and screwed to predesigned drill holes. The guide facilitates the predrilling of screw holes and the initiation of cutting for buccal, lingual and external oblique ridge corticotomy using a piezosurgery device., Conclusion: Based on our experience, we think that this guide is a promising new tool to assist BSSO. It helped limit the extent of tissue detachment required and provided the strength necessary for accurate bone cutting and drilling. It also allowed the accurate fixation of preformed plates to obtain occlusion as per virtual planning., (Copyright © 2017 Elsevier Masson SAS. All rights reserved.)