Experiences of nursing students in A peer mentoring program during their clinical practices. A qualitative study.

BACKGROUND: Clinical placements allow nursing students to develop the skills and attitudes necessary to provide care. Peer mentoring programmes seem to facilitate these achievements, but there are very few studies on the effects of peer mentoring on clinical placements and what it can bring to both mentors and mentees. AIM: To describe the perspectives of nursing students on a peer mentoring programme during their clinical placements. DESIGN: A qualitative descriptive and exploratory study. SETTINGS AND PARTICIPANTS: First year and third year nursing students were included. METHODS: Focus groups were conducted with students after they participated in a peer mentoring programme during their clinical practice rotation. RESULTS: The support received from the student mentors was very important both academically and personally. Mentors also acknowledged having improved their teaching and leadership skills. CONCLUSIONS: Our results can be applied to future studies to inform peer mentoring programmes as a complementary teaching tool in clinical placements to improve leadership and empowerment in nursing students.

Early exploration of the economic impact of transradial access (TRA) versus transfemoral access (TFA) for neurovascular procedures in Spain.

INTRODUCTION: Transfemoral access (TFA) is the primary access approach for neurointerventional procedures. Transradial access (TRA) is established in cardiology due to its lower complications, yet, it is at its early stages in neuroprocedures. This study performs an early exploration of the economic impact associated with the introduction of TRA in diagnostic and therapeutic neuroprocedures from the Spanish NHS perspective. METHODS: An economic model was developed to estimate the cost and clinical implications of using TRA compared to TFA. Costs considered access-related, complications and recovery time costs obtained from local databases and experts' inputs. Clinical inputs were sourced from the literature. A panel of eight experts from different Spanish hospitals, validated or adjusted the values based on local experience. Hypothetical cohorts of 10,000 and 1000 patients were considered for diagnostic and therapeutic neuroprocedures respectively. Deterministic sensitivity analysis was performed. RESULTS: TRA in diagnostic procedures was associated with lower costs with savings ranging between €486 and €157 depending on the TFA recovery time considered. TRA is estimated to lead to 158 fewer access-site complications. In therapeutic procedures, TRA resulted in 76.4 fewer complications and was estimated to be cost-neutral with an incremental cost of €21.56 per patient despite recovery times were not included for this group. Variation of the parameters in the sensitivity analysis did not change the direction of the results. LIMITATIONS: Clinical data was obtained from literature validated by experts therefore results generalizability is limited. In therapeutic neuroprocedures, there is an experience imbalance between approaches and recovery times were not included hence the total impact is not fully captured. CONCLUSIONS: The early economic model suggests that implementing TRA is associated with reduced costs and complications in diagnostic procedures. In therapeutic procedures, TRA lead to fewer complications and it is estimated to be cost-neutral, however its full potential still needs to be quantified.

Evaluation of Interactions of Added Soybean Peroxidase with Other Nutrients Present in Fish Feeds Using an In Vitro Digestive Simulation.

Peroxidase (PO) has been applied in different areas of industrial biotechnology, including the control of contaminants like aflatoxin B1 in fish feeds. However, its potential negative interactions with the macro and micro components of feeds have not been evaluated. The aim of this study was to evaluate the impact of PO's addition to a feed on compounds like fatty acids and polyphenols using an in vitro simulation of the digestive tract of the tilapia. The influence on fatty acids was determined by changes in the peroxide index, with the feed including PO presenting values four times higher than those of the control feed. On the other hand, the in vitro digestive simulation also evidenced an effect of PO on the bioaccessibility of polyphenols significantly influenced by the total digestion time and temperature. The bioaccessibility of polyphenol ranged from 2.09 to 16.23 µmol of the total Trolox equivalent antioxidant capacity for the combinations evaluated in the study. The greatest bioaccessibility was observed at the central point under the following conditions of digestive hydrolysis: pH of 7, 30 °C, 4.5 h of digestive hydrolysis and an absence of PO.

Use of polyphenolic fingerprints established by comprehensive two-dimensional liquid chromatography for the classification of honeys according to their floral origin.

In this work, the polyphenolic composition of honeys from three different floral origins (chestnut, heather, and thyme), coming from different geographical areas of Spain was investigated. First, samples were characterized in terms of total phenolic content (TPC) and antioxidant capacity, which was established by three different assays. The results revealed that the studied honeys presented similar TPCs and antioxidant capacities, with a wide variability within each floral origin. Next, a comprehensive two-dimensional liquid chromatography method was developed for the first time to establish polyphenol fingerprints of the three types of honeys, after optimizing the separation in terms of column combination and mobile phase gradient programs. After that, the detected common peaks were used for the construction of a linear discriminant analysis (LDA) model able to discriminate honeys according to their floral origin. The LDA model obtained was adequate for the classification of the floral origin of the honeys based on polyphenolic fingerprint data.

Detection of Mycobacterial DNA in Human Bone Marrow.

Bone marrow is a cell-rich tissue of the reticuloendothelial system essential in the homeostasis and accurate functioning of hematopoiesis and of the immune system; moreover, it is also rich in lipids because it contains marrow adipocytes. This work aimed to evaluate the detection of mycobacterial DNA in human bone marrow as a tool to understand the complex pathology caused by the main pathogen Mycobacterium tuberculosis (Mtb). Formalin-fixed paraffin-embedded human bone marrow samples were studied using both conventional PCR + hybridization and in situ PCR to figure out the cell distribution of the targeted DNA. Samples were retrospectively collected from HIV+ patients with microbiologically proved mycobacterial infection and from subjects without evidence of infection. Mycobacterium avium (Mav) as well as Mtb DNA was detected in both settings, including tissues with and without granulomas. We detected DNA from both mycobacterial species, using in situ PCR, inside bone marrow macrophages. Other cell types, including adipocytes, showed positive signals only for Mtb DNA. This result suggested, for the first time, that marrow adipocytes could constitute an ideal reservoir for the persistence of Mtb, allowing the bacilli to establish long-lasting latent infection within a suitable lipid environment. This fact might differentiate pathogenic behavior of non-specialized pathogens such as Mav from that of specialized pathogens such as Mtb.

Implant-supported full-arch rehabilitation with immediate loading using two different digital impression techniques: a case report with 2-year follow-up.

Immediate full-arch loading is a highly complex and technique-sensitive procedure. Digital impression techniques aim to replace conventional analog systems to carry out dental treatments in a more predictive, safer, and less time-consuming way. This case report describes a patient with a guarded periodontal prognosis, who was rehabilitated with implant-supported fixed prostheses after full-mouth extractions. Immediate full-arch loading was performed by means of two digital impression systems: photogrammetric technology with PIC dental in the maxillary arch, and MedicalFit in the mandible. Immediate provisional prostheses in acrylic resin (polymethyl methacrylate) were milled and placed within 12 hours after implant placement surgeries. Both provisional structures fitted properly providing adequate esthetics and function. After the implant osseointegration period, final digital impressions were registered, and definitive zirconia full-arch implant-supported prostheses were delivered. The 24-month follow-up did not show biologic or mechanical complications.

Medication Adherence and Contraceptive Counseling.

Combined oral contraceptives (COC) are a very popular form of birth control. Incorrect use and lack of adherence to treatment reduce the effectiveness of this method. Having a standard tool to identify poor-adherence profiles quickly and objectively can be helpful for midwives and potentially for COC users. The MMAS-4 adherence scale has been used in various medical fields, but there is little evidence of its potential in contraceptive consultation. This paper presents a piece of multicenter observational research based on a sample of 327 women who had attended contraceptive counselling in Spain and were COC users or had informed the midwife that they want to start to use this method. Two interviews were conducted: at the time of consultation and after one year. In our research, the MMAS-4 identified high-risk behaviors: during the 1-year follow-up period, COC users classified as poorly adherent had a significantly higher risk of missed contraceptive pills, more incidents and problems related to the method of contraception, as well as a lower degree of satisfaction with the contraceptive method. One case of unplanned pregnancy and two cases of emergency contraception were identified, all of them corresponding to poorly adherent women. The use of MMAS-4 in consultation can improve midwives' contraceptive counselling.

Organization and Characterization of the Promoter Elements of the rRNA Operons in the Slow-Growing Pathogen Mycobacterium kumamotonense.

The slow-growing, nontuberculous mycobacterium Mycobacterium kumamotonense possesses two rRNA operons, rrnA and rrnB, located downstream from the murA and tyrS genes, respectively. Here, we report the sequence and organization of the promoter regions of these two rrn operons. In the rrnA operon, transcription can be initiated from the two promoters, named P1 rrnA and PCL1, while in rrnB, transcription can only start from one, called P1 rrnB. Both rrn operons show a similar organization to the one described in Mycobacterium celatum and Mycobacterium smegmatis. Furthermore, by qRT-PCR analyses of the products generated from each promoter, we report that stress conditions such as starvation, hypoxia, and cellular infection affect the contribution of each operon to the synthesis of pre-rRNA. It was found that the products from the PCL1 promoter of rrnA play a pivotal role in rRNA synthesis during all stress conditions. Interestingly, the main participation of the products of transcription from the P1 promoter of rrnB was found during hypoxic conditions at the NRP1 phase. These results provide novel insights into pre-rRNA synthesis in mycobacteria, as well as the potential ability of M. kumamotonense to produce latent infections.

Galactose-functionalized methacrylate polymers as affinity sorbents for extraction of food allergen lectins.

In this study, glycidyl methacrylate (GMA)-based materials functionalized with different galactose derivatives were prepared to be used as affinity sorbents for solid-phase extraction (SPE) of several food allergen lectins (such as phytohemagglutinin (PHA)). First, GMA-based polymers were synthesized and then galactose derivatives were immobilized onto the GMA surface using two different synthetic routes. In the first approach, the bare polymer was modified with ethylenediamine and glutaraldehyde, and subsequently two galactose derivatives were immobilized. In the second strategy, the starting polymer was modified with cystamine and gold nanoparticles (AuNPs), on which a thiolated galactose derivative was subsequently anchored. The resulting materials were characterized by scanning electron microscopy and used as SPE sorbents for the isolation of PHA (as probe protein) from food matrices. Different SPE parameters (sample pH, eluent solution composition, binding capacity, sample volume, selectivity and reusability) were evaluated. The material that provided the best PHA recovery (98%) was the one obtained in the second approach, being this material successfully applied to the selective extraction of PHA and other similar lectins from different foods (red and lima dried beans, fresh soybeans and biscuits containing soybean protein traces as indicated in their label). After SDS-PAGE of eluates, all samples only exhibited the characteristic PHA band around 30 kDa, suggesting the high potential of the developed material for application in food allergy field.

Reflective based learning for nursing ethical competency during clinical practices.

BACKGROUND: A combination of theoretical and practical approaches is required to learn and acquire ethical competencies in caring. Occasionally, reflection on practical action differs from theoretical learning. In the context of reflective learning, issues such as ethical values can be discussed since they evoke conflict among nursing students. AIM: To identify ethical conflicts encountered by nursing students during clinical placements and to determine their cooperation strategies. RESEARCH DESIGN: Qualitative study with a content analysis according to Elo and Kinglas framework. PARTICIPANTS AND RESEARCH CONTEXT: Students enrolled in a nursing program at a Spanish university aged between 22 and 35, mainly women. METHODOLOGY: The study includes 134 ethical reflections from nursing students in the last year of the nursing program, written during their clinical practices in a variety of learning environments. The research team analyzed the reflections using an inductive content analysis method. ETHICAL CONSIDERATIONS: Ethical permission was obtained by the management center according to Law 3/2028, and all the participants accepted to participate through the informed consent form. FINDINGS: Three main categories emerged from the analysis of the ethical reflections: (1) evaluation of professional performance and patient care; (2) the student as the protagonist of the dilemma; (3) student coping. Student dilemmas and concerns are related to ignorance, student-patient communication, mistakes made and self-confidence. Some situations conflict with the autonomy of patients and their rights, and can contribute to stressful situations for patients. Stress factors include hospital routines, which the patient cannot modify, and asymmetric relationships with staff, which encourage passivity. CONCLUSION: All ethical problems detected by the students begin with the professional-patient relationship, including issues related to bad news, errors or malpractice. Reflection on the ethical values of nursing, both in the classroom and in clinical practices, allows students to develop a greater ethical awareness of care, enhancing their decision-making skills in ethical dilemmas.

Complete Genome Sequence Analysis of Kribbella sp. CA-293567 and Identification of the Kribbellichelins A & B and Sandramycin Biosynthetic Gene Clusters.

Minor genera actinomycetes are considered a promising source of new secondary metabolites. The strain Kribbella sp. CA-293567 produces sandramycin and kribbellichelins A & B In this work, we describe the complete genome sequencing of this strain and the in silico identification of biosynthetic gene clusters (BGCs), focusing on the pathways encoding sandramycin and kribbellichelins A-B. We also present a comparative analysis of the biosynthetic potential of 38 publicly available genomes from Kribbella strains.

Baricitinib or imatinib in hospitalized COVID-19 patients: Results from COVINIB, an exploratory randomized clinical trial.

Baricitinib and imatinib are considered therapies for coronavirus disease 2019 (COVID-19), but their ultimate clinical impact remains to be elucidated, so our objective is to determine whether these kinase inhibitors provide benefit when added to standard care in hospitalized COVID-19 patients. Phase-2, open-label, randomized trial with a pick-the-winner design conducted from September 2020 to June 2021 in a single Spanish center. Hospitalized adults with COVID-19 pneumonia and a symptom duration ≤10 days were assigned to 3 arms: imatinib (400 mg qd, 7 days) plus standard-care, baricitinib (4 mg qd, 7 days) plus standard-care, or standard-care alone. Primary outcome was time to clinical improvement (discharge alive or a reduction of 2 points in an ordinal scale of clinical status) compared on a day-by-day basis to identify differences ≥15% between the most and least favorable groups. Secondary outcomes included oxygenation and ventilatory support requirements, additional therapies administered, all-cause mortality, and safety. One hundred and sixty-five patients analyzed. Predefined criteria for selection of the most advantageous arm were met for baricitinib, but not for imatinib. However, no statistically significant differences were observed in formal analysis, but a trend toward better results in patients receiving baricitinib was found compared to standard care alone (hazard ratio [HR] for clinical improvement: 1.41, 95% confidence intervals [CI]: 0.96-2.06; HR for discontinuing oxygen: 1.46, 95% CI: 0.94-2.28). No differences were found regarding additional therapies administered or safety. Baricitinib plus standard care showed better results for hospitalized COVID-19 patients, being the most advantageous therapeutic strategy among those proposed in this exploratory clinical trial.

Skin absorption of inorganic nanoparticles and their toxicity: A review.

The role of inorganic nanoparticles in our society is increasing every day, from its use in sunscreens to their introduction in analytical laboratories, pharmacy, medicine, agricultural and other uses. Therefore, in order to establish precautions as well as correct handling of this type of material by operators, it is important to determine the ability of these compounds to travel through the different layers of the skin and to study their possible toxicological effects. In this sense, several authors have studied the ability of inorganic nanoparticles to penetrate the skin barrier by diverse methodologies in in vivo and in vitro modes. In the first case, most of the studies have been performed with animal skins that can imitate the human one (porcine, mouse and guinea pigs, among others), although human skin from surgery have been also explored. However, the use of animals is a common model that should be avoided in the following years due to ethical issues. In this sense, the use of in vitro methodologies is also usually selected to study the dermal absorption of nanoparticles through the skin. Nevertheless, most of the studies are performed with authentic animal skins, instead of the use of synthetic skins that imitate the permeability of our skin system, which has been scarcely studied. In addition, most of the literature is focused in achieving high-transdermal uptake to use nanoparticles (not only inorganic) as carriers for drugs, but little efforts have been done in the study of their inherent percutaneous absorption and toxicity. For these reasons, this review covers the current state-of-the-art of dermal absorption of inorganic nanoparticles in skin and their possible toxicity taking into account that people can be in contact with these nanomaterials in daily life, work or other places. In this sense, the observed results showed that the nanoparticles rarely reach the blood circulatory system, and no big toxicological effects were commonly found when in vivo and actual skin was used. In addition, similar results were found when synthetic skins were used, demonstrating the possibility of avoiding animals in these studies. In any case, more studies covering the dermal absorption of nanoparticles should be performed to have a better understanding of how nanoparticles can affect our health.

Local Welfare Systems and Health Inequalities: The Effects of Institutional Overlapping and Local Variations.

A growing research agenda shows the importance of local welfare systems in understanding socio-spatial inequalities in health. Welfare services provided by local governments overlap with those provided by other levels of government. Thus, differences in the provision of welfare services between municipalities could explain differences in residents' health, moderating the magnitude of health inequalities if local governments deploy actions capable of positively influencing the social determinants of health. This article attempts to analyse this idea in the Spanish case, exploring the influence of local policies according to the orientation of municipal spending on three indicators of the population's health status: self-perceived health, healthy practices and activity limitations due to health problems. A multilevel cross-sectional study was designed using information from two waves of the 2006-2007 and 2011-2012 National Health Survey for the population aged 15 years and older (N = 31,378) residing in Spanish municipalities of 20,000 inhabitants or over (N = 373). The results show that the magnitude of inequalities in self-perceived health, in the adoption of healthy practices and in daily activity limitations by social class are smaller as municipalities" spending was oriented towards policy areas considered as redistributive. Therefore, the proposed institutional overlap thesis could help understand the role of subnational governments on the magnitude of health inequalities, as well as in comparative analysis between countries with institutional systems in which local governments have a greater or lesser capacity to provide welfare services.

Immunogenicity of Mycobacterial Extracellular Vesicles Isolated From Host-Related Conditions Informs About Tuberculosis Disease Status.

Tuberculosis (TB) still represents a major global health problem affecting over 10 million people worldwide. The gold-standard procedures for TB diagnosis are culture and nucleic acid amplification techniques. In this context, both lipoarabinomannan (LAM) urine test and rapid molecular tests have been major game changers. However, the low sensitivity of the former and the cost and the prohibitive infrastructure requirements to scale-up in endemic regions of the latter, make the improvement of the TB diagnostic landscape a priority. Most forms of life produce extracellular vesicles (EVs), including bacteria despite differences in bacterial cell envelope architecture. We demonstrated that Mycobacterium tuberculosis (Mtb), the causative agent of TB, produces EVs in vitro and in vivo as part of a sophisticated mechanism to manipulate host cellular physiology and to evade the host immune system. In a previous serology study, we showed that the recognition of several mycobacterial extracellular vesicles (MEV) associated proteins could have diagnostic properties. In this study, we pursued to expand the capabilities of MEVs in the context of TB diagnostics by analyzing the composition of MEVs isolated from Mtb cultures submitted to iron starvation and, testing their immunogenicity against a new cohort of serum samples derived from TB+ patients, latent TB-infected (LTBI) patients and healthy donors. We found that despite the stringent condition imposed by iron starvation, Mtb reduces the number of MEV associated proteins relative to iron sufficient conditions. In addition, TB serology revealed three new MEV antigens with specific biomarker capacity. These results suggest the feasibility of developing a point-of-care (POC) device based on selected MEV-associated proteins.

Diurnal variation on tear stability and correlation with tear cytokine concentration.

PURPOSE: To investigate the effect of time of day on tear evaporation rate (TER) and tear break-up time, and its possible relationship with the concentration of inflammatory tear molecules (cytokines) in healthy subjects. METHODS: Participants with healthy ocular surfaces attended 3 visits, including the screening visit (V0), the 2nd visit (V1) and the 3rd visit (V2). There were 7-day intervals between visits. Participants with Dry Eye Disease (DED) were excluded by using appropriate clinical tests during V0. Clinical evaluation (TER and Non-Invasive Tear Break-Up Time (NITBUT)) and tear collection were performed during V1 and V2, between 9 and 10AM and 3-4PM. The relative humidity and temperature of the examination room were also measured. The tear fluid concentrations of 15 cytokines were measured by multiplex bead analysis. RESULTS: Seven men and 10 women (mean age ± S.D; 25.1 ± 6.63 years old) participated in the study. There were no differences in neither the TER and NITBUT outcomes, nor humidity and temperature among times or visits. Eleven out of the 15 cytokines measured were detectable in tear fluids in > 50% of the participants. In the tear levels, no significant (p > 0.05) inter- and/or intra-day differences were detected for EGF, fractalkine, IL-1RA, IL-1ß and IP-10. However, significant inter-day differences were found in the tear levels of IL-10 (p = 0.027), IFN-γ (p = 0.035) and TNF-α(p = 0.04) and intra-day differences in the tear levels of IL-8/CXCL8 (p = 0.034) and MCP-1 (p = 0.002). A significant correlation between TER and IL1-ß, IL-2, and Fractalkine (p = 0.03, p = 0.03 and p = 0.046, respectively) was found at V1. CONCLUSIONS: NITBUT and TER values had no significant variability over the course of a day (AM versus PM), or on different days in healthy participants when humidity and temperature were constant. However, some tear molecule levels did show inter- and intra-day variability, having an inconsistent and moderate correlation with TER diurnal variation.

Reticular framework materials in miniaturized and emerging formats in analytical chemistry.

In recent years, important efforts have been put into miniaturization, coming on the scene formats such as chips, 3D-printed objects and paper-based devices. These systems have been applied to biological and chemical processes taking profit of their advantages such as waste reduction, low cost, portability, etc. Despite their benefits, there is a need to continue developing easier-to-use devices with enhanced performance addressed to face the current analytical challenges. In this sense, reticular porous materials such as metal- (MOFs) and covalent- (COFs) organic frameworks with unique features including tailorable porous architectures and tunable chemistry have attracted a lot of attention in various fields. Nevertheless, the combination of these materials with miniaturized and emerging formats has been scarcely investigated. This review is intended to bridge this gap and highlight the recent contributions of these materials in these analytical formats. Thus, this work aims to provide a comprehensive review of the field, highlighting incorporation strategies into the functional supports available to date, and the applications of the resulting systems in both off-site laboratory studies (mostly dedicated to (micro)extraction purposes) and on-site analysis. Finally, a discussion of challenges and future directions in this field is also given.

Automatic and non-targeted analysis of the volatile profile of natural and alkalized cocoa powders using SBSE-GC-MS and chemometrics.

A total of 56 key volatile compounds present in natural and alkalized cocoa powders have been rapidly evaluated using a non-target approach using stir bar sorptive extraction gas chromatography mass spectrometry (SBSE-GC-MS) coupled to Parallel Factor Analysis 2 (PARAFAC2) automated in PARADISe. Principal component analysis (PCA) explained 80% of the variability of the concentration, in four PCs, which revealed specific groups of volatile characteristics. Partial least squares discriminant analysis (PLS-DA) helped to identify volatile compounds that were correlated to the different degrees of alkalization. Dynamics between compounds such as the acetophenone increasing and toluene and furfural decreasing in medium and strongly alkalized cocoas allowed its differentiation from natural cocoa samples. Thus, the proposed comprehensive analysis is a useful tool for understanding volatiles, e.g., for the quality control of cocoa powders with significant time and costs savings.

New Life Transition of Former Caregivers: Positive Mental Health Approach.

After the end of their time as a caregiver, former caregivers have needs and feelings that have been subject to little study to date. The aim of the study is to determine and analyse the feelings, perceptions and practices of former caregivers in the reconstruction of their daily lives. This is a qualitative study based on the Grounded Theory developed by Charmaz. The study involved 14 former caregivers who had cared for their relative for more than 2 years and who had stopped caring for them more than 2 years previously. Fourteen in-depth interviews were conducted and data were collected over 13 months between 2015 and 2017. Data were analysed using the Grounded Theory Method. In addition, this study was approved by the ethics committee of the Institut Universitari d'Investigació en Atenció Primària Jordi Gol. The former caregiver experiences a transition, which begins in the days before the death of their relative and may continue for more than 3 years. Three critical moments in the post-caring transition were found: (1) the post-caring emptiness; (2) the end of the period as a caregiver; and (3) the movement towards a new life. Family and professional support is needed during this transition. Former caregivers experience a transition in the rebuilding of their daily lives; furthermore, former caregivers may be a source of support for other caregivers, which is linked to positive mental health factors. Healthcare organisations need to acknowledge the emotional, psychosocial and psychological health of former caregivers.

Accuracy of Digital Dental Implants Impression Taking with Intraoral Scanners Compared with Conventional Impression Techniques: A Systematic Review of In Vitro Studies.

The aim of this systematic review was to evaluate the in vitro accuracy of dental implants impressions taken with intraoral scanner compared with impressions taken with conventional techniques. Two independent reviewers conducted a systematic electronic search in the PubMed, Web of Science and Scopus databases. Some of the employed key terms, combined with the help of Boolean operators, were: "dental implants", "impression accuracy", "digital impression" and "conventional impression". Publication dates ranged from the earliest article available until 31 July 2021. A total of 26 articles fulfilled the inclusion criteria: 14 studies simulated complete edentation (CE), nine partial edentation (PE) and only two simulated a single implant (SI); One study simulated both CE and SI. In cases of PE and SI, most of the studies analyzed found greater accuracy with conventional impression (CI), although digital impression (DI) was also considered adequate. For CE the findings were inconclusive as six studies found greater accuracy with DI, five found better accuracy with CI and four found no differences. According to the results of this systematic review, DI is a valid alternative to CI for implants in PE and SI, although CI appear to be more accurate. For CE the findings were inconclusive, so more studies are needed before DI can be recommended for all implant-supported restorations.