Annals of 3D printed medicine最新文献

In pharmaceutics, 3D printing is considered as a promising future technology for fabricating more complex patient-specific drug delivery systems (DDSs). An anti-staphylococcal herbal preparation, “Chlorophyllipt”, is produced mainly in a liquid form by the pharmaceutical industry in Ukraine, and it is composed of an ethanolic eucalypt extract (EE). Since staphylococcal infections have become a true challenge for the health care in all over the world, it would be relevant and justified to develop the aqueous gels of the present EE applicable for the 3D printing of the corresponding solid DDSs. The aim of the present study was to develop a novel polyethylene oxide (PEO) gel loaded with EE for a semi-solid extrusion (SSE) 3D printing and to print the corresponding oral solid DDSs with different sizes and shapes. For SSE 3D printing, we prepared and tested total ten (10) different aqueous PEO gel formulations loaded with EE. Prior to 3D printing, the physical appearance, homogeneity, injection force and viscosity of the gels were investigated. The EE-PEO gels were printed to lattice- and round-shaped solid DDSs with the head speed of 0.5 mm/s, and the weight (mass uniformity) and effective surface area of the printed systems were determined. The most feasible EE-PEO gel for SSE 3D printing comprised of 10 mg/ml of EE, 30 mg/ml of eumulgin and 20 mg/ml of ascorbic acid in a 20-% aqueous PEO gel. The key process parameters of the SSE 3D printing were identified and verified. The printing quality of EE-PEO DDSs were very good, thus showing compatibility of a plant extract and carrier polymer. Such 3D-printed antimicrobial DDSs can be used for example in the treatment of skin wounds and infections of the oral cavity.

Purpose

From May 2021 the European regulation EU2017/745 covers the manufacture of medical devices in healthcare facilities under certain conditions. In this context, the use of 3D printing and free software can be combined to provide a solution to some of the problems for which no commercial product can be found in brachytherapy.

What we present here is a procedure for the design, using open source software, and manufacture, with Fused Deposition Modeling technology, of brachytherapy surface moulds.

Material and methods

The procedure starts with a CT scan of the patient treatment area with radiopaque markers. 3D slicer software is then used to delimit the applicator mould that follows the patient's surface. After this, we use the Freecad software to design the channels where we will insert the plastic tubes through which the radiation source will deliver the treatment. We also use the Meshmixer software to make the final delimitation of the applicator edges as well as to find and correct any inconsistency.

Results

Moulds created by means of 3D printing allow us to combine the precise fit to the patient's surface of homemade solutions with the geometric accuracy between catheters of commercial products. This is clearly seen when treating small and irregular surfaces such as the ear pinna.

Conclusion

Manufacture of brachytherapy surface moulds with FDG technology is a good example of customized solutions in healthcare facilities supported by new European legistation. If we add to this the use of free open source software, we are facing an alternative to classics solutions used up to now in superficial brachytherapy.

Food printing technology is going to be the promising technology of future. Advances in 3D food Printing or additive manufacturing technology adds extra dimension to the established food practices and offer opportunities for new interactive experiences. This paper aims to deliver the central flow of 3D food printing process and extends to summarize its knowledge towards the perception of personalized nutrition. The initial flow emphasizes the broad categories of food printing materials and further, to stream the concept of personalized nutrition, a unique attention is focused on latest technological innovations in the 3D printed foodstuffs with different nutritional approaches viz., nutrition enhancement, minerals/vitamins fortification, functional ingredients enrichment and the development of alternative foods. In addition to current prominent scientific researches, literature stuffing adds a new flavor drawing attention on several industrially developed 3D food printed products that are reached and inline to the market. A prominent highlight was embarked on recent technical progress in the development of pharma foods, insect and plant based meat alternatives using 3D printing techniques. It is strongly believed that personalization and customization of 3D printed foods could be a future talk in compromising, unsatisfied nutritional problems and eradicating several chronical diseases in the pandemic era.

The application of 3D Printing (3DP) for use in fracture casts and orthopaedic splints has been explored in several studies. The challenge of 3D printed casts is their size and relatively long production time compared to traditional/fibreglass casts. This preliminary study aims to determine the effects of three specific parameters specifically in the context of manufacturing Total Contact Casts (TCCs) for the treatment of diabetic foot ulcers.

The effects of printing parameters have been evaluated previously in the literature. However, there are little data in single experiments on layer height ratio dependent on line width; typically, lower values of layer height have been assessed that remain constant with all line widths. The combination of line width, layer height and print orientation have been evaluated here, with a focus on achieving quickest possible print time without sacrificing part strength in the context of 3D printed TCCs.

Flexural testing was conducted on FDM-printed PLA test specimens with 36 different treatments, adjusting the above parameters. The relationship between part strength (flexural modulus and maximum flexural stress) and print time was investigated.

It was determined that a low layer height could be paired with a high line width to achieve optimal part strength, considering also print time. The specific application, and associated direction of forces/loads is an important consideration when selecting a print orientation to optimise mechanical performance. A case example applied to the printing of a TCC is also presented.

Since the 1980s, 3D printing has considerably broadened its field of application. Although only recently developed, there are now several techniques that allow the custom design of 3D objects. Plastic surgery, with its wide range of surgical indications, also benefits from the various 3D printing techniques. It brings a precious help to the surgeon, whether it is within the framework of pre-operative planning, of the custom design of cutting tools in maxillofacial surgery, or within a pedagogical framework with the learning of surgical techniques to students or for the provision of more precise information to patients. This work first recalls the different modalities of three-dimensional printing, then describes the main uses of 3D printing in plastic surgery.

Aims

Twin blocks are appliances used for Class II skeletal discrepancies, where the lower jaw is positioned more posteriorly compared to the upper. The conventional method of fabrication of this appliance is tedious and labour-intensive; hence this study intends to explore the feasibility of a digital workflow to three-dimensionally (3D) print them.

Methods

Three sets of twin blocks, identical except for amount of offset (0.0 mm, 0.1 mm and 0.2 mm), were designed and 3D printed for 5 anonymized scans of patients with Class II skeletal discrepancies. The intaglio surfaces of the 0.0 mm offset twin blocks were scanned and superimposed onto their original computer-aided-design files. The resultant colour maps, root mean square (RMS) deviations, and percentage in-tolerance values at thresholds of 0.1 mm and 0.2 mm were assessed. The fit and retention of all twin blocks were assessed on their 3D printed models via a fit and retention score (FRS).

Results

The median RMS deviation was 0.10 mm; percentage in-tolerance values at thresholds of 0.1 mm and 0.2 mm were 79.90%, and 94.51%. Printing deviations occurred most often at labial and incisal edges anteriorly, and buccal and occlusal surfaces posteriorly. There was no significant difference between the total FRS for the three groups (p = 0.076). However, the frequency of satisfactory scores for upper fit (p = 0.049), lower fit (p = 0.018), upper retention (p = 0.038) and lower retention (p = 0.015) differed significantly between the three groups.

Conclusion

This study demonstrated the viability of a digital workflow to 3D print twin blocks. Print accuracy was satisfactory, with 0.1 mm offset providing the best fit and retention.

During imaging follow-up, the residual dissection after a type A repair dissection could progress and may require repair of the aortic arch and the distal aorta. Our approach for repairing the evolving dissection includes open aortic arch replacement involving all 3 supra-aortic branches in combination with the frozen elephant trunk (FET) technique (n = 14). Distal arch repair combines a vascular and endovascular treatment to treat aortic arch disease (n = 13). A 3D printed aorta model has been used preoperatively and intraoperatively to improve surgical results. Hereby we report our aortic arch surgical experience and results in the treatment for this challenging pathology.

Lactobacilli, play a beneficial role in the female reproductive tract (FRT), regulating pH via lactic acid metabolism to help maintain a healthy environment. Bacterial vaginosis (BV) is characterized by a dysregulated flora in which anaerobes such as Gardnerella vaginalis (Gardnerella) create a less acidic environment. Current treatment focuses on antibiotic administration, including metronidazole, clindamycin, or tinidazole; however, lack of patient compliance as wel as antibiotic resistance may contribute to 50% recurrence within a year. Recently, locally administered probiotic such as Lactobacillus crispatus (L. crispatus) have been evaluated as a prophylactic against recurrence. To mitigate the lack of patient compliance, sustained probiotic delivery has been proposed via 3D-bioprinted delivery vehicles. Successful delivery depends on a variety of vehicle fabrication parameters influencing timing and rate of probiotic recovery; detailed evaluation of these parameters would benefit from computational modeling complementary to experimental evaluation. This study implements a novel simulation platform to evaluate sustained delivery of probiotics from 3D-bioprinted scaffolds, taking into consideration bacterial lactic acid production and associated pH changes. The results show that the timing and rate of probiotic recovery can be realistically simulated based on fabrication parameters that affect scaffold degradation and probiotic survival. Longer term, the proposed approach could help personalize localized probiotic delivery to the FRT to advance women's health.

Adolescent idiopathic scoliosis (AIS) is a noticeable spinal deformity in both adult and adolescent population. In majority of the cases, the gold standard of treatment is surgical intervention. Technological advancements in medical imaging and 3D printing have revolutionised the surgical planning and intraoperative decision making for surgeons in spinal surgery. However, its applicability for planning complex spinal surgeries is poorly documented with human subjects. The objective of this study is to evaluate the accuracy of 3D printed models for complex spinal deformities based on Cobb angles between 40° to 95°.This is a retrospective cohort study where, five CT scans of the patients with AIS were segmented and 3D printed for evaluating the accuracy. Consideration was given to the Inter-patient and acquisition apparatus variability of the CT-scan dataset to understand the effect on trueness and accuracy of the developed CAD models. The developed anatomical models were re-scanned for analysing quantitative surface deviation to assess the accuracy of 3D printed spinal models. Results show that the average of the root mean square error (RMSE) between the 3DP models and virtual models developed using CT scan of mean surface deviations for the five 3d printed models was found to be 0.5±0.07 mm. Based on the RMSE, it can be concluded that 3D printing based workflow is accurate enough to be used for presurgical planning for complex adolescent spinal deformities. Image acquisition and post processing parameters, type of 3D printing technology plays key role in acquiring required accuracy for surgical applications.