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To investigate the short-term optical, chemical and morphological changes in Invisalign appliances.

In hip arthroplasty, preoperative planning is fundamental to reaching a successful surgery. Nowadays, several software tools for computed tomography (CT) image processing are available. However, research studies comparing segmentation tools for hip surgery planning for patients affected by osteoarthritic diseases or osteoporotic fractures are still lacking. The present work compares three different software from the geometric, dimensional, and usability perspectives to identify the best three-dimensional (3D) modelling tool for the reconstruction of pathological femoral heads. Syngo.via Frontier (by Siemens Healthcare) is a medical image reading and post-processing software that allows low-skilled operators to produce prototypes. Materialise (by Mimics) is a commercial medical modelling software. 3D Slicer (by slicer.org) is an open-source development platform used in medical and biomedical fields. The 3D models reconstructed starting from the in vivo CT images of the pathological femoral head are compared with the geometries obtained from the laser scan of the in vitro bony specimens. The results show that Mimics and 3D Slicer are better for dimensional and geometric accuracy in the 3D reconstruction, while syngo.via Frontier is the easiest to use in the hospital setting. [ABSTRACT FROM AUTHOR]

AIM: The purpose of this study is to compare the stress effects developed on the periodontal ligaments and teeth by three different types of mandibular advancement devices (MADs) using a finite element method (FEM) analysis. Introduction: Obstructive sleep apnea (OSA) is a disease with a high prevalence and, in recent years, the use of MADs as an alternative or support treatment to the continuous positive airway pressure (CPAP) has spread. Their use finds relative contraindications in the case of partial edentulism and severe periodontal disease. Given the widespread of periodontal problems, it is essential to know the effects that these devices cause on the periodontal ligament of the teeth. Materials and methods: Starting from the computed tomography (CT) scan of a patient's skull, 3D reconstructions of the maxilla and mandible were implemented. Three different MADs were prepared for the patient, then 3D scanned, and lastly, coupled with the 3D models of the jaws. The devices have two different mechanics: One has a front reverse connecting rod (OrthoapneaTM), and two have lateral propulsion (SomnodentTM and HerbstTM). A FEM analysis was performed to calculate the stress applied on periodontal ligaments, on every single tooth and the displacement vectors that are generated by applying an advancement force on the mandible. Results: HerbstTM and SomnodentTM devices present very similar stress values, mainly concentrated on lateral teeth, but in general, the forces are very mild and distributed. The maximum stresses values are 3.27 kPa on periodontal ligaments and 287 kPa on teeth for SomnodentTM and 3.56 kPa on periodontal ligaments and 302 kPa on teeth for HerbstTM. OrthoapneaTM has, instead, higher and concentrated stress values, especially in the anterior maxillary and mandibular area with 4.26 kPa and 600 kPa as maximum stress values, respectively, on periodontal ligaments and teeth. Conclusions: From the results, it is concluded that devices with a bilateral mechanism generate less and more distributed stress than an anterior connecting rod mechanism. Therefore, they may be advisable to patients with compromised periodontal conditions in the anterior area. [ABSTRACT FROM AUTHOR]

The paper aims to evaluate the effects caused by a Mandibular Advancement Device (MAD) for Obstructive Sleep Apnoea Syndrome (OSAS) treatment. This study is based on Finite Element Method (FEM) for evaluating the load distribution on temporomandibular joint, especially on the mandibular condyle and disc, and on periodontal ligaments. The stress values on condyle and periodontal ligaments lead authors to consider MAD a safe procedure even for a long period. The obtained results also show the relationship between MAD material and load distribution at the periodontal ligaments. The paper is a step toward future analyses for studying and comparing the effects of MAD features, such as material, shape and dimensions, in order to allow the clinician prescribing the most fitting device. [ABSTRACT FROM AUTHOR]

The article focuses on the establishment of a three-dimensional cell model for studying uterine leiomyosarcoma, specifically examining the morphology and growth of spheroids formed using an agarose-based culture system, providing insights into tumor pathophysiology and potential drug testing applications.

Purpose – The purpose of this study is to show how selective laser sintering (SLS) manufacturing of bioresorbable scaffolds is used for applications in bone tissue engineering. Design/methodology/approach – Polycaprolactone (PCL) scaffolds were computationally designed and then fabricated via SLS for applications in bone and cartilage repair. Findings – Preliminary biocompatibility data were acquired using human mesenchymal stem cells (hMSCs) assuring a satisfactory scaffold colonization by hMSCs. Originality/value – A promising procedure for producing porous scaffolds for the repair of skeletal defects, in tissue engineering applications, was developed. [ABSTRACT FROM AUTHOR]

Objective: To evaluate volumetric variations in the palate following rapid expansion, both immediately after treatment and over time. Materials and Methods: The sample was composed of 30 patients in early mixed dentition treated with a Haas-type device cemented onto the primary second molars. The mean age of the patients upon commencement of expansion was 7 years and 6 months (standard deviation [SD], 12 months). Measurement of palatal volume was conducted via 3D acquisition of plaster models using laser scanning before treatment (Ti), upon device removal (T2), and 2.6 years afterward (T3). Results: The volume of the palate increased in a statistically significant fashion from Ti to T2 and from Ti to T3, and it decreased in a nonsignificant fashion from T2 to T3. Conclusions: Palatal volume significantly increases with rapid maxillary expansion (RME) treatment with insignificant relapse. The use of virtual 3D models with the aid of Apposite software permits evaluation of the morphologic and volumetric changes induced by orthodontic treatment. [ABSTRACT FROM AUTHOR]

The increase in concrete structures' durability is a milestone to improve the sustainability of buildings and infrastructures. In order to ensure a prolonged service life, it is necessary to detect the deterioration of materials by means of monitoring systems aimed at evaluating not only the penetration of aggressive substances into concrete but also the corrosion of carbon-steel reinforcement. Therefore, proper data collection makes it possible to plan suitable restoration works which can be carried out with traditional or innovative techniques and materials. This work focuses on building heritage and it highlights the most recent findings for the conservation and restoration of reinforced concrete structures and masonry buildings.

The paper represents the "state of the art" on sustainability in construction materials. In Part 1 of the paper, issues related to production, microstructures, chemical nature, engineering properties, and durability of mixtures based on binders alternative to Portland cement were presented. This second part of the paper concerns the use of traditional and innovative Portland-free lime-based mortars in the conservation of cultural heritage, and the recycling and management of wastes to reduce consumption of natural resources in the production of construction materials. The latter is one of the main concerns in terms of sustainability since nowadays more than 75% of wastes are disposed of in landfills.

This review presents "a state of the art" report on sustainability in construction materials. The authors propose different solutions to make the concrete industry more environmentally friendly in order to reduce greenhouse gases emissions and consumption of non-renewable resources. Part 1-the present paper-focuses on the use of binders alternative to Portland cement, including sulfoaluminate cements, alkali-activated materials, and geopolymers. Part 2 will be dedicated to traditional Portland-free binders and waste management and recycling in mortar and concrete production.

Quality of service, in terms of improvement in patient satisfaction, is an increasingly important objective in all medical fields, and is especially imperative in orthodontics due to the high numbers of patients treated. Information technology can provide a meaningful contribution to bettering treatment processes, and we maintain that systems such as CAD, CAM and CAE, although initially conceived for industrial purposes, should be evaluated, studied and customized with a view to use in medicine. The present study aims to evaluate Reverse Engineering (RE) and Rapid Prototyping (RP) in order to define an ideal chain of advanced technological solutions to support the critical processes of orthodontic activity.