Influences of patient positioning and general anesthesia on condylar position and surgical accuracy in orthognathic surgery.

Objectives: To assess the effect of patient positioning and general anesthesia on the condylar position in orthognathic surgery.

Materials And Methods: This prospective study included patients undergoing orthognathic surgery between 2019 and 2020. Four weeks prior to surgery (T0) cone-beam computed tomography (CBCT) scans and intra-oral scans (IOS) were acquired in an upright position.

Safety of vertical osteotomies in segmental Le Fort I procedures: a one-year radiological follow-up study.

The aim of this study was to evaluate dental and periodontal injuries and radiological bone healing at vertical osteotomies in patients treated with segmental Le Fort I (LFI) osteotomy, using cone beam computed tomography (CBCT) scans. This retrospective study analyzed 105 patients who underwent segmental LFI osteotomy. Vertical osteotomies were performed between the lateral incisor and canine using a bur and osteotome.

Accuracy and stability of the condyle position after orthognathic surgery: A retrospective study.

The purpose of this study was to evaluate the accuracy and stability of condylar positioning in patients treated with bimaxillary procedures compared with patients treated with maxillary procedures alone. All patients had undergone treatment at Odense University Hospital and were treated with inferior maxillary procedures. The primary outcome was changes in condyle position and the primary predictor variable was time: pre-operative (T) measurements to 1-week post-operative (T) and 1-year post-operative (T) measurements.

Novel Developments in the Treatment of Multiple Myeloma-Associated Bone Disease.

Osteolytic bone disease is present in about 80% of patients with multiple myeloma at the time of diagnosis. Managing bone disease in patients with multiple myeloma is a challenge and requires a multi-faceted treatment approach with medication, surgery, and radiation. The established treatments with intravenous or subcutaneous antiresorptives can cause debilitating adverse events for patients, mainly osteonecrosis of the jaw, which, traditionally, has been difficult to manage.

Schottky barrier lowering due to interface states in 2D heterophase devices.

The Schottky barrier of a metal-semiconductor junction is one of the key quantities affecting the charge transport in a transistor. The Schottky barrier height depends on several factors, such as work function difference, local atomic configuration in the interface, and impurity doping. We show that also the presence of interface states at 2D metal-semiconductor junctions can give rise to a large renormalization of the effective Schottky barrier determined from the temperature dependence of the current.

Contemporary Techniques in Orbital Reconstruction: A Review of the Literature and Report of a Case Combining Surgical Navigation, Computer-Aided Surgical Simulation, and a Patient-Specific Implant.

Purpose: Complex orbital fractures can be surgically challenging because the orbital cavity contains several vital anatomic structures and visibility is limited. We present a case in which computer-aided surgical simulation (CASS), surgical navigation (SN), and a patient-specific implant (PSI) were used. Furthermore, the reported data regarding this topic were systematically searched and investigated.

Inferior Maxillary Repositioning Remains Stable 1 Year After Surgery but Entails a High Risk of Osteosynthesis Failure.

Purpose: Inferior maxillary repositioning has continued to be among the most unstable orthognathic procedures. The overall purpose of the present study was to measure skeletal stability after inferior maxillary repositioning.

Materials And Methods: We implemented a retrospective cohort study.

QuantumATK: an integrated platform of electronic and atomic-scale modelling tools.

QuantumATK is an integrated set of atomic-scale modelling tools developed since 2003 by professional software engineers in collaboration with academic researchers. While different aspects and individual modules of the platform have been previously presented, the purpose of this paper is to give a general overview of the platform. The QuantumATK simulation engines enable electronic-structure calculations using density functional theory or tight-binding model Hamiltonians, and also offers bonded or reactive empirical force fields in many different parametrizations.

Synovial Cysts in the Temporomandibular Joint: a Case Report and Critical Review of the Literature.

Background: Synovial cysts of the temporomandibular joint are rare and treatment is based on consensus from cases reporting unilateral successful outcomes. A patient with a synovial cyst is presented, treated with successful surgical excision of the cyst, but without remission of joint symptoms. Furthermore, the case is supplemented by a critical, literature review.

Does Mandible-First Sequencing Increase Maxillary Surgical Accuracy in Bimaxillary Procedures?

Purpose: In bimaxillary procedures, it is important to know how the chosen sequence affects the surgical outcome. The purpose of this study was to explore whether the theoretical advantages of using the mandible-first procedure were supported by clinical data.

Materials And Methods: The authors performed a retrospective investigation on a cohort compiled from 3 published retrospective studies.

Patient-specific 3D printed plates improve stability of Le Fort 1 osteotomies in vitro.

Purpose: Selective laser melting used to manufacture patient-specific 3D-printed (PSP) plates is a delicate process, which may introduce weakened areas in the plates, with risk of fracture. This in vitro study's purpose was to test the ability of PSP plates to stabilize Le Fort I osteotomies compared with manually adapted stock plates. The study's objectives were to measure the force needed to compress the osteotomy and evaluate whether the PSP plates would break during compression.

Patient-Specific Printed Plates Improve Surgical Accuracy In Vitro.

Purpose: It remains unclear to what extent patient-specific printed plates can improve surgical outcomes in orthognathic procedures. This study aimed to quantify the surgical accuracy of patient-specific printed plates in vitro and to compare the results with patients' actual surgical outcomes.

Patients And Methods: This in vitro study enrolled 20 postoperative orthognathic surgical patients, all treated with inferior maxillary repositioning.

Autotransplantation of premolars: does surgeon experience matter?

Autotransplantation of premolars is a well-established method to rehabilitate aplasia of premolars. Nevertheless, with the introduction of titanium implants, not all surgical units offer this procedure. The aim of this study was to examine the predictability of autotransplantation of premolars on orthodontic indication as suggested by Andreasen et al.

Surgical Accuracy in Inferior Maxillary Reposition.

Purpose: Inferior maxillary repositioning is among the least stable and least predictable orthognathic procedures. The purpose of this study was to investigate whether posterior movement occurred with inferior maxillary repositioning and to analyze potential causes.

Materials And Methods: This retrospective observational study evaluated all consecutive patients treated at the Department of Oral and Maxillofacial Surgery of the Odense University Hospital (Odense, Denmark) with inferior maxillary repositioning from 2011 to 2013.

Complex band structure and electronic transmission eigenchannels.

It is natural to characterize materials in transport junctions by their conductance length dependence, β. Theoretical estimations of β are made employing two primary theories: complex band structure and density functional theory (DFT) Landauer transport. It has previously been shown that the β value derived from total Landauer transmission can be related to the β value from the smallest |k| complex band; however, it is an open question whether there is a deeper relationship between the two.

A 3-Dimensional Approach for Analysis in Orthognathic Surgery-Using Free Software for Voxel-Based Alignment and Semiautomatic Measurement.

Purpose: In orthognathic surgery, the repeatability of 3-dimensional (3D) measurements is limited by the need for manual reidentification of reference points, which can incorporate errors greater than 1 mm for every 4 repeated measurements. This report describes a semiautomatic approach to decrease the manual reidentification error. This study evaluated the repeatability of surgical outcome measurements using the semiautomatic approach.

Proximity Band Structure and Spin Textures on Both Sides of Topological-Insulator/Ferromagnetic-Metal Interface and Their Charge Transport Probes.

The control of recently observed spintronic effects in topological-insulator/ferromagnetic-metal (TI/FM) heterostructures is thwarted by the lack of understanding of band structure and spin textures around their interfaces. Here we combine density functional theory with Green's function techniques to obtain the spectral function at any plane passing through atoms of BiSe and Co or Cu layers comprising the interface. Instead of naively assumed Dirac cone gapped by the proximity exchange field spectral function, we find that the Rashba ferromagnetic model describes the spectral function on the surface of BiSe in contact with Co near the Fermi level E, where circular and snowflake-like constant energy contours coexist around which spin locks to momentum.

Method for determining optimal supercell representation of interfaces.

The geometry and structure of an interface ultimately determines the behavior of devices at the nanoscale. We present a generic method to determine the possible lattice matches between two arbitrary surfaces and to calculate the strain of the corresponding matched interface. We apply this method to explore two relevant classes of interfaces for which accurate structural measurements of the interface are available: (i) the interface between pentacene crystals and the (1 1 1) surface of gold, and (ii) the interface between the semiconductor indium-arsenide and aluminum.

Surgical Navigation: A Systematic Review of Indications, Treatments, and Outcomes in Oral and Maxillofacial Surgery.

Purpose: This systematic review investigates the most common indications, treatments, and outcomes of surgical navigation (SN) published from 2010 to 2015. The evolution of SN and its application in oral and maxillofacial surgery have rapidly developed over recent years, and therapeutic indications are discussed.

Materials And Methods: A systematic search in relevant electronic databases, journals, and bibliographies of the included articles was carried out.

Surgical Splint Design Influences Transverse Expansion in Segmental Maxillary Osteotomies.

Purpose: In segmental maxillary procedures, it is imperative to obtain as much of the planned expansion as possible. Lack of obtained expansion, in addition to late relapse after splint removal, can result in relapse of the posterior crossbite. This study investigated the influence of 2 surgical splint designs on achieving the planned transverse expansion in bimaxillary surgery with segmental maxillary procedures.

Changes in Upper Airway Volume Following Orthognathic Surgery.

Reduced volume of the internal skeletal dimensions of the face is 1 of the main causes of obstructive sleep apnea, and attention to patients' airways is necessary when planning orthognathic treatment. This study aims to describe changes in upper airway volume following virtually planned orthognathic surgery.A retrospective pilot study was designed with 30 randomly selected patients (10 men and 20 women, aged 23.

Surgical accuracy of three-dimensional virtual planning: a pilot study of bimaxillary orthognathic procedures including maxillary segmentation.

This retrospective study evaluated the precision and positional accuracy of different orthognathic procedures following virtual surgical planning in 30 patients. To date, no studies of three-dimensional virtual surgical planning have evaluated the influence of segmentation on positional accuracy and transverse expansion. Furthermore, only a few have evaluated the precision and accuracy of genioplasty in placement of the chin segment.

Improved initial guess for minimum energy path calculations.

A method is presented for generating a good initial guess of a transition path between given initial and final states of a system without evaluation of the energy. An objective function surface is constructed using an interpolation of pairwise distances at each discretization point along the path and the nudged elastic band method then used to find an optimal path on this image dependent pair potential (IDPP) surface. This provides an initial path for the more computationally intensive calculations of a minimum energy path on an energy surface obtained, for example, by ab initio or density functional theory.

Virtual planning in orthognathic surgery.

Numerous publications regarding virtual surgical planning protocols have been published, most reporting only one or two case reports to emphasize the hands-on planning. None have systematically reviewed the data published from clinical trials. This systematic review analyzes the precision and accuracy of three-dimensional (3D) virtual surgical planning of orthognathic procedures compared with the actual surgical outcome following orthognathic surgery reported in clinical trials.

First-principles modeling of electron transport.

The dimensions of electronic devices are rapidly decreasing and there is a need for a new generation of modeling tools that can accurately calculate the electrical properties of devices where atomic scale details and quantum effects are important. A promising framework for such calculations is density functional theory within the non-equilibrium Green's function formalism (NEGF-DFT). In this paper we present the basic framework and applications of the formalism.