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The purpose of this paper is to describe two different approaches for manufacturing pre-formed titanium meshes to assist prosthetically guided bone regeneration of atrophic maxillary arches. Both methods are based on the use of additive manufacturing (AM) technologies and aim to limit at the minimal intervention the bone reconstructive surgery by virtual planning the surgical intervention for dental implants placement.

Two patients with atrophic maxillary arches were scheduled for bone augmentation using pre-formed titanium mesh with particulate autogenous bone graft and alloplastic material. The complete workflow consists of four steps: three-dimensional (3D) acquisition of medical images and virtual planning, 3D modelling and design of the bone augmentation volume, manufacturing of biomodels and pre-formed meshes, clinical procedure and follow up. For what concerns the AM, fused deposition modelling (FDM) and direct metal laser sintering (DMLS) were used.

For both patients, a post-operative control CT examination was scheduled to evaluate the progression of the regenerative process and verify the availability of an adequate amount of bone before the surgical intervention for dental implants placement. In both cases, the regenerated bone was sufficient to fix the implants in the planned position, improving the intervention quality and reducing the intervention time during surgery.

A comparison between two novel methods, involving AM technologies are presented as viable and reproducible methods to assist the correct bone augmentation of atrophic patients, prior to implant placement for the final implant supported prosthetic rehabilitation.

The purpose of the paper was to present a specific case study of how 3D printing was introduced in the chest wall construction process of a specific patient with unique medical condition. A life-size 3D model of the patient’s chest wall was 3D printed for pre-surgical planning. The intent was to eliminate the need for operative exposure to map the pathological area. The model was used for preoperative visualization and formation of a 1-mm thick titanium plate implant, which was placed in the patient during chest wall reconstructive surgery. The purpose of the surgery was to relive debilitating chronic pain due to right scapular entrapment.

The patient was born with a twisted spine. Over time, it progressed to severe and debilitating scoliosis, which required the use of a thoracic brace. Computerized tomography (CT) data were converted to a 3D printed model. The model was used to size and form a 1-mm thick titanium plate implant. It was also used to determine the ideal location for placement of the plate during thoracotomy preoperatively.

The surgery, aided by the model, was successful and resulted in a significantly smaller incision. The techniques reduced invasiveness and enabled the doctors to conduct the procedure efficiently and decreased surgery time. The patient experienced relief of the chronic debilitating pain and no longer need the thoracic brace.

The 3D model facilitated pre-operative planning and modeling of the implant. It also enabled accurate incision locations of the thoracotomy site and placement of the implant. Although chest wall reconstruction surgeries have been undertaken, this paper documents a specific case study of chest wall construction fora specific patient with unique pathological conditions.

Orbital fractures are the most commonly encountered midfacial fractures, and usually, the fracture involves the floor and/or the medial wall of the orbit. This paper aims to present an innovative approach for primary and secondary reconstructions of fractured orbital walls through the use of computer-assisted techniques and additive manufacturing.

First, through the 3D anatomical modelling, the geometry of the implant is shaped to fill the orbital defect and recover the facial symmetry. Subsequently, starting from the modelled implant, a customised mould is designed taking into account medical and technological requirements.

The selective laser sintered mould is able to model and form several kind of prosthetic materials (e.g. titanium meshes and demineralised bone tissue), resulting in customised implants and allowing accurate orbital cavity reconstructions. The case study proved that this procedure, at the same time, reduces the morbidity on the patients, the duration of surgery and the related costs.

This innovative approach has great potential, as it is an easy and in-office procedure, and it offers several advantages over other existing methods.

This study aims to assess the design, manufacturing and surgical implantation of three-dimensional (3D) customized implants, including surgical preoperative planning, surgery and postoperative results, for cranioplasty along with zygomatic and orbital floor implants using additive manufacturing (AM) technics for a 23-year-old female who suffered from severe craniomaxillofacial trauma.

The skull biomodel was produced in polyamide while implants were made of Ti-6Al-4V alloy by AM.

The method enabled perfectly fitting implants and anatomical conformance with the craniomaxillofacial defect, providing complete healing for the patient. Surgical planning using a customized 3D polyamide biomodel was effective. This proved to be a powerful tool for medical planning and manufacturing of customized implants, as complete healing and good craniofacial aesthetic results were observed.

Satisfactory surgical procedures, regarding surgery time reduction and good craniofacial aesthetic results, were achieved. Furthermore, the 3D titanium customized implants represented a favorable alternative for the repair of craniomaxillofacial defects.

To relieve intracranial pressure and save patient inflicted with severe head injury, neurosurgeons restore cranial defects. These defects can be caused because of trauma or diseases (Osteomyelitis of bone) which are treated by cranioplasty, using the preserved bone of patient. In case of non-availability of bone, a cranial implant is generated using a biocompatible synthetic material, but this process is less accurate and time-consuming. Hence, this paper aims to present the use of rapid prototyping technology that allows the development of a more accurate patient-specific template and saves the surgery time.

A five-year-old girl patient having cranial defect was taken up for cranioplasty. CT (computed tomography) scans of the patient were used to generate 3D design of the implant suitable to conceal the defect on the left frontal portion using CAD/CAM (computer-aided design/ computer-aided manufacturing) software. The design was used for 3D printing to manufacture a base template, which was finally used to fabricate the actual implant using Simplex® P bone cement material to conceal the defect.

Surgery using Simplex® P implant was performed successfully on the patient, giving precise natural curvature to left frontal portion of the patient, decreasing surgery time by about 30 per cent.

The case demonstrates the development of a convenient, time-saving and aesthetically superior digital procedure to treat cranial defect in the absence of preserved bone flap using CT scan as input. 3D modelling and printing were deployed to produce an accurate template which was used to generate an implant using bone cement biocompatible material.

ACEL — Tay Bridge cathodic protection. Aberdeen Corrosion Engineers Ltd in conjunction with R B R (Scotland) Limited, have been awarded a major contract for structural repairs and installation of cathodic protection to supporting columns of the River Tay A92 Road Bridge at Dundee. Work commenced during July 1989, and comprises installation of expanded titanium mesh using both sprayed and poured mortar overlays.

Insoluble and therefore oxygen developing anodes tend to destroy additives in plating baths. With a modified mixed metal oxide coated anode, it is possible to reduce the consumption of additives in copper electrolytes and to reduce the formation of Sn⁴⁺ in acid tin electrolytes. Favourable applications for this new anode type are under discussion.

Boost additive for nickel plating. Permalite has developed a boost additive, Solarbrite 125, which works with Solarbrite 3000, 4000 and 6000 to bring the following important benefits to the nickel plating industry:‐

Evidence of corrosion of reinforncing steel in concrete has become a familiar sight on United States highways and parking structures. Decks and substructures expected to provide maintenance‐free service for 40 years often require major repair within 5 to 10 years, and frequently have to be replaced after only 15 years of service. At first, poor construction practice and excessive loading were the primary factors blamed by most highway engineers. However, a geographical distribution of the problem pointed to a relationship with salt used to melt snow and ice, or present in seawater and salt spray. Only recently, as research has continued and as field evaluation tools were developed, has corrosion of reinforcing steel been understood as the major cause of this problem.

Introduction Cathodic protection may be defined as a means of rendering a metal, immersed in an electrolytically conducting environment, immune from corrosion by causing direct current electricity to flow from the environment into the metal. This paper is not intended to elaborate in depth on the application of cathodic protection, which is exhaustively covered elsewhere, but in general the technique is commonly applied to pipelines, storage tanks, jetties, ships and offshore platforms, where the electrolyte is soil or natural waters. See Figure 1 (appendix I).