The re-emerging role of linoleic acid in paediatric asthma.

Asthma is the most common chronic disease within the paediatric population. Although it is multifactorial, its onset may be linked to early-life exposures with subsequent impact on immune system development. Microbial and dietary metabolic products have been implicated in the development and exacerbation of paediatric asthma. Linoleic acid is the most common omega-6 polyunsaturated fatty acid in the Western diet. In this review, we summarise the literature regarding the involvement of linoleic acid in the development of and its impact on existing paediatric asthma. First, we summarise the existing knowledge surrounding the relationship between human microbial metabolism and allergic diseases in children. Next, we examine cellular or animal model-based mechanistic studies that investigated the impact of dietary- and microbial-derived linoleic acid metabolites on asthma. Finally, we review the literature investigating the impact of linoleic acid metabolites on the development and exacerbation of childhood asthma. While there is conflicting evidence, there is growing support for a role of linoleic acid in the onset and pathophysiology of asthma. We recommend that additional cellular, animal, and longitudinal studies are performed that target linoleic acid and its metabolites.

Glutarate regulates T cell metabolism and anti-tumour immunity.

T cell function and fate can be influenced by several metabolites: in some cases, acting through enzymatic inhibition of α-ketoglutarate-dependent dioxygenases, in others, through post-translational modification of lysines in important targets. We show here that glutarate, a product of amino acid catabolism, has the capacity to do both, and has potent effects on T cell function and differentiation. We found that glutarate exerts those effects both through α-ketoglutarate-dependent dioxygenase inhibition, and through direct regulation of T cell metabolism via glutarylation of the pyruvate dehydrogenase E2 subunit. Administration of diethyl glutarate, a cell-permeable form of glutarate, alters CD8+ T cell differentiation and increases cytotoxicity against target cells. In vivo administration of the compound is correlated with increased levels of both peripheral and intratumoural cytotoxic CD8+ T cells. These results demonstrate that glutarate is an important regulator of T cell metabolism and differentiation with a potential role in the improvement of T cell immunotherapy.

Comparison of heat production and bone architecture changes in the implant site preparation with compressive osteotomes, osseodensification technique, piezoelectric devices, and standard drills: an ex vivo study on porcine ribs.

This study aimed at investigating differences in heat generation and bone architecture following four different implant site preparation techniques: compressive osteotomes, conventional drills, osseodensification (OD mode with osseodensification drills), and piezoelectric systems. Porcine rib bones were used as a model for implant surgery. Thermocouples were employed to measure temperature changes, and micro-CT to assess the bone architecture. The primary stability and insertion torque values of the implants placed in the differently prepared sites were assessed. The temperature changes were higher with Piezo. The average primary stability using the ISQ scale was the greatest for drills (76.17 ± 0.90) and the lowest for osteotomes (71.50 ± 11.09). Insertion torque was significantly higher with the osseodensification method (71.67 ± 7.99 Ncm) in comparison to drills, osteotomes, and piezo. Osteotomes showed the highest bone to implant contact percentage (39.83 ± 3.14%) and average trabecular number (2.02 ± 0.21 per mm), while drills exhibited the lowest (30.73 ± 1.65%; 1.37 ± 0.34 per mm). Total implant site bone volume was the highest with osseodensification (37.26 ± 4.13mm3) and the lowest for osteotomes (33.84 ± 3.84mm3). Statistical analysis showed a high primary stability and decrease in temperature during implant site preparation with osseodensification technique. The results support the use of osseodensification technique for implant site preparation.

The octadecanoids: an emerging class of lipid mediators.

Oxylipins are enzymatic and non-enzymatic metabolites of mono- or polyunsaturated fatty acids that encompass potent lipid mediators including the eicosanoids and docosanoids. Previously considered of low interest and often dismissed as 'just fat', octadecanoid oxylipins have only recently begun to be recognized as lipid mediators in humans. In the last few years, these compounds have been found to be involved in the mediation of multiple biological processes related to nociception, tissue modulation, cell proliferation, metabolic regulation, inflammation, and immune regulation. At the same time, the study of octadecanoids is hampered by a lack of standardization in the field, a paucity of analytical standards, and a lack of domain expertise. These issues have collectively limited the investigation of the biosynthesis and bioactivity of octadecanoids. Here, we present an overview of the primary enzymatic pathways for the oxidative metabolism of 18-carbon fatty acids in humans and of the current knowledge of the major biological activity of the resulting octadecanoids. We also propose a systematic nomenclature system based upon that used for the eicosanoids in order to avoid ambiguities and resolve multiple designations for the same octadecanoid. The aim of this review is to provide an initial framework for the field and to assist in its standardization as well as to increase awareness of this class of compounds in order to stimulate research into this interesting group of lipid mediators.

Development of a Chiral Supercritical Fluid Chromatography-Tandem Mass Spectrometry and Reversed-Phase Liquid Chromatography-Tandem Mass Spectrometry Platform for the Quantitative Metabolic Profiling of Octadecanoid Oxylipins.

Octadecanoids are broadly defined as oxylipins (i.e., lipid mediators) derived from 18-carbon fatty acids. In contrast to the well-studied eicosanoids, there is a lack of analytical methods for octadecanoids, hampering further investigations in the field. We developed an integrated workflow combining chiral separation by supercritical fluid chromatography (SFC) and reversed-phase liquid chromatography (LC) coupled to tandem mass spectrometry detection for quantification of a broad panel of octadecanoids. The platform includes 70 custom-synthesized analytical and internal standards to extend the coverage of the octadecanoid synthetic pathways. A total of 103 octadecanoids could be separated by chiral SFC and complex enantioseparations could be performed in <13 min, while the achiral LC method separated 67 octadecanoids in 13.5 min. The LC method provided a robust complementary approach with greater sensitivity relative to the SFC method. Both methods were validated in solvent and surrogate matrix in terms of linearity, lower limits of quantification (LLOQ), recovery, accuracy, precision, and matrix effects. Instrumental linearity was good for both methods (R2 > 0.995) and LLOQ ranged from 0.03 to 6.00 ng/mL for SFC and 0.01 to 1.25 ng/mL for LC. The average accuracy in the solvent and surrogate matrix ranged from 89 to 109% in SFC and from 106 to 220% in LC, whereas coefficients of variation (CV) were <14% (at medium and high concentrations) and 26% (at low concentrations). Validation in the surrogate matrix showed negligible matrix effects (<16% for all analytes), and average recoveries ranged from 71 to 83%. The combined methods provide a platform to investigate the biological activity of octadecanoids and expand our understanding of these little-studied compounds.

Illegal drugs and periodontal conditions.

In recent years, the practice of dentistry and periodontology has become complicated by several risk factors, including the treatment of an increasing number of patients with substance use disorder. This review presents an update in the current literature of the impact of illegal drug use on periodontal conditions and their possible effect as risk factors or indicators. The main illegal drugs that may have an impact on periodontal health and conditions are described, including their effect, medical manifestations, risks, and the overall effect on oral health and on the periodontium. Where available, data from epidemiologic studies are analyzed and summarized. The clinical management of periodontal patients using illegal drugs is reported in a comprehensive approach inclusive of the detection of illicit drug users, screening, interviewing and counseling, the referral to treatment, and the dental and periodontal management. With regard to the impact of illegal substance use on periodontal conditions, there is moderate evidence that regular long-term use of cannabis is a risk factor for periodontal disease, manifesting as a loss of periodontal attachment, deep pockets, recessions, and gingival enlargements. Limited evidence also shows that the use of cocaine can cause a series of gingival conditions that mostly presents as chemical induced-traumatic lesions (application of cocaine on the gingiva) or necrotizing ulcerative lesions. There is a scarcity of data regarding the impact of other drug use on periodontal health. There is evidence to suggest that regular long-term use of cannabis is a risk factor for periodontal disease and that the use of cocaine can cause a series of periodontal conditions. The dental treatment of subjects that use illegal substances is becoming more common in the daily clinical practice of periodontists and other dental clinicians. When the clinicians encounter such patients, it is essential to manage their addiction properly taking into consideration the impact of it on comprehensive dental treatment. Further studies and clinical observations are required to obtain sound and definitive information.

Titanium Surface Decontamination: A Systematic Review of In Vitro Comparative Studies.

PURPOSE: To achieve high plaque removal around peri-implant tissues, noninvasive cleaning methods that guarantee the long-term success and survival of titanium implants should be established. This systematic review aimed to systematically evaluate in vitro investigations assessing different treatment modalities to decontaminate titanium surfaces, with special focus on the most effective cleaning procedures. MATERIALS AND METHODS: PRISMA guidelines were adopted in an electronic search conducted through MEDLINE, Scopus, and Google Scholar databases to identify studies on mechanical, chemical, or laser decontamination modalities up to November 2019. RESULTS: The search resulted in 326 articles; after removing duplicates and reading titles, abstracts, and full texts, 38 articles were ultimately processed for data extraction. Mechanical decontamination provided better results in comparison to laser and chemical procedures. Among mechanical modalities, air abrasion showed the best cleaning effectiveness. Conversely, upon comparison of the chemical methods, chlorhexidine demonstrated comparable results with all tested substances and even with photodynamic therapy. Among different lasers, the results showed that the diode was more promising compared with the other tested lasers. CONCLUSION: This review demonstrated that there is still no consensus on which technique performs better. However, mechanical decontamination yielded more favorable results than laser and chemical methods. This aspect would support the hypothesis that decontamination procedures adopted in a combination fashion, which includes mechanical procedures, may provide better clinical results than when used alone.

Working characteristics for practising dental hygienists in two countries in different hemispheres.

OBJECTIVES: The study aimed to collect and compare practising characteristics for dental hygienists (DHs) in New Zealand (NZ) and Sweden. METHODS: Dental hygienists from NZ and Sweden were invited to participate in an anonymous online survey focussing on their working practices. An email, with a link to the online survey and a participant information sheet, was sent to DHs registered with their professional association in their respective country. Frequency analyses and cross-tabulations were conducted using chi-square and Fisher's exact tests to investigate possible statistical associations to allow for comparisons between the countries. RESULTS: DH is a female-dominated workforce with equal distribution of gender in both countries. The majority of DHs in NZ worked in private practice while Swedish DHs mostly worked in the public sector. NZ participants were younger and with a more recent qualification than their Swedish counterparts. The highest degree of education was a PhD for DHs working in Sweden, compared with a master's degree for NZ participants. The majority of participants from both countries treated patients 65 years of age or older, with the most common medical conditions being cardiovascular disease and diabetes mellitus. The most common dental condition observed/treated was periodontal disease. Over 60% agreed to have an understanding of information technology (IT). The most used technical equipment was digital radiology, followed by other diagnostic tools. CONCLUSION: Findings confirm previous international data on demographical uptake for the DH workforce in NZ and Sweden. A coherence was seen in patient characteristics, DHs' attitudes towards information technology and use of technical equipment.

Clinical outcomes of laser microtextured implants or abutments: A systematic review.

PURPOSE: To investigate the effect of laser microtextured collars or laser microtextured abutments on clinical measures that may relate to improved implant success and survival. MATERIALS AND METHODS: This review was registered on the PROSPERO database and conducted according to Preferred Reporting Items for Systematic Reviews and Meta-Analysis guidelines. MEDLINE (via PubMed) and Embase were screened for studies with at least 10 participants and followed up for at least 1 year, reporting on the following clinical outcomes: radiographic marginal bone level, peri-implant probing depth, soft tissue index and failure rates of implants with laser microtextured collars or laser microtextured abutments. The quality of the studies was assessed using the Cochrane risk-of-bias tool or the Newcastle-Ottawa scale. RESULTS: After removal of duplicates, 86 articles were identified. A total of 25 articles were included after screening. Four were randomised controlled trials, two were non-randomised controlled trials, two were prospective studies, five were retrospective cohort studies and twelve had no control group. Most comparative studies reported that laser microtextured collar implants had less marginal bone loss and shallower peri-implant probing depth than machined collar implants. Only two studies had controls other than machined collar implants; in these, the use of laser microtextured collar implants was not observed to be significantly different. Three studies reported reduced marginal recession in laser microtextured collar implants when compared to machined collar controls. No difference in failure rate was observed between laser microtextured collar and machined collar implants. One study reported on peri-implant diseases and favoured laser microtextured collar implants. Three papers reported using laser microtextured abutments with no control, but no specific conclusions could be drawn. CONCLUSIONS: Laser microtextured collar implants appear to reduce marginal bone loss and peri-implant probing depth when compared to machined collar implants. There is weak evidence to suggest that laser microtextured collar implants may also improve aesthetic outcomes and reduce incidence of disease. Research is required regarding laser microtextured abutments, and studies comparing laser microtexturing with alternative solutions are also lacking.

Cold atmospheric plasma coupled with air abrasion in liquid medium for the treatment of peri-implantitis model grown with a complex human biofilm: an in vitro study.

OBJECTIVE: Treatment of implants with peri-implantitis is often unsuccessful due to residual microbial biofilm hindering re-osseointegration. The aim of this study was to treat biofilm-grown titanium (Ti) implants with different modalities involving air abrasion (AA) and cold atmospheric plasma (CAP) to compare the effectiveness in surface decontamination and the alteration/preservation of surface topography. MATERIALS AND METHODS: Saliva collected from a peri-implantitis patient was used to in vitro develop human biofilm over 35 implants with moderately rough surface. The implants were then mounted onto standardized acrylic blocks simulating peri-implantitis defects and treated with AA (erythritol powder), CAP in a liquid medium, or a combination (COM) of both modalities. The remaining biofilm was measured by crystal violet (CV). Surface features and roughness before and after treatment were assessed by scanning electron microscope (SEM). The data were statistically analyzed using Kruskal-Wallis followed by Tukey's multiple comparison test. RESULTS: In the present peri-implantitis model, the human complex biofilm growth was successful as indicated by the statistical significance between the negative and positive controls. All the treatment groups resulted in a remarkable implant surface decontamination, with values very close to the negative control for AA and COM. Indeed, statistically significant differences in the comparison between the positive control vs. all the treatment groups were found. SEM analysis showed no post-treatment alterations on the implant surface in all the groups. CONCLUSIONS: Decontamination with AA delivering erythritol with or without CAP in liquid medium demonstrated compelling efficacy in the removal of biofilm from implants. All the tested treatments did not cause qualitative alterations to the Ti surface features. No specific effects of the CAP were observed, although further studies are necessary to assess its potential as monotherapy with different settings or in combination with other decontamination procedures. CLINICAL RELEVANCE: CAP is a promising option in the treatment of peri-implantitis because it has potential to improve the elimination of bacterial plaque from implant surfaces, in inaccessible pockets or during open-flap debridement, and should stimulate the process of the re-osseointegration of affected dental implants by not altering surface features and roughness.

Operators matter - An assessment of the expectations, perceptions, and performance of dentists, postgraduate students, and dental prosthetist students using intraoral scanning.

OBJECTIVE: to assess the expectations, perceptions and performance of different operators with varying backgrounds and training in the use of full-arch intraoral scanning (IOS). METHODS AND MATERIALS: Dentists (DENT), postgraduate dental students (DPG), and student prosthetists (PROS) were invited to join an IOS training workshop. Participants completed a satisfactory scan of a mannikin-mounted typodont with the total scanning time (TST) recorded. They also completed anonymised pre and post-training questionnaires covering their background, and IOS expectations and experience. Statistical analysis was performed using the Mann-Whitney U, Kruskal Wallis, and chi-square tests. Open-ended questions were analysed manually and using Leximancer. RESULTS: Twenty-seven participants were recruited: 10 DENT; 10 PROS; and 7 DPG. Positive expectations of IOS was reported by 93 % of participants. Combined TST was 285 ± 83 s, with the PROS TST significantly longer (p < 0.05, 337 ± 79 s). Further training need was reported by 60 % of PROS and 50 % of DENT versus 14 % of DPG. Positive IOS experience was reported by 96 % of participants, 74 % perceived it to be accurate, and 63 % found it easy to use. Eighty-five percent of all participants stated that cost would influence their decision of adopting IOS in their practice. CONCLUSION: Expectations and perceptions of IOS were overwhelmingly positive, irrespective of operator background and experience. Scanning performance and training needs depended on the operator's background. Cost of IOS remains a barrier to acquiring the technology. CLINICAL SIGNIFICANCE: IOS training must be customised to accommodate the needs of different operators. The cost of IOS needs revision to improve its accessibility.

Biological Oriented Immediate Loading: A New Mathematical Implant Vertical Insertion Protocol, Five-Year Follow-Up Study.

One of the current major challenges in implant therapy is to minimize marginal bone loss around implants, since it can trigger bacterial colonization of the implant's neck, leading to its failure. The present study aimed (1) to scientifically validate a new mathematical rule based on soft tissues thickness, for choosing the correct implant position with respect to the bone level, in order to provide a better tissue adaptation to the abutment/implant surface to avoid bacterial invasion, and (2) to apply this mathematical rule to the Biological Oriented Immediate Loading (B.O.I.L.) surgical protocol, avoiding peri-implant bone resorption. N. 127 implants were inserted following B.O.I.L. protocol: implants were placed according to the mathematical rule Y = X - 3, which correlates the position of the implant from the bone crest level (Y) with the thickness of the soft tissues (X). All the implants were inserted in fresh extraction sockets, and immediately loaded with temporary abutments and prostheses. Bone levels were evaluated through radiographic examination just after surgical procedure (T0), and after 10 days (10D), 6 months (6M), 1 year (1Y), and 5 years (5Y). After 5 years, the implant survival rate was 100%, with a medium marginal bone loss around implants of 0.0704 mm (SD = 0.169 mm). One-way ANOVA, followed by Tukey's multiple comparison test was performed for statistical evaluations (p < 0.05). This protocol provided a safe and successful procedure, with a good soft tissue seal against bacterial challenge. The application of the mathematical rule allows the implant placement in a correct vertical position from the bone crest, avoiding bone resorption and bacterial infiltrations. Moreover, the use of Multi Unit Abutment (MUA) determined a stable biological seal, favouring the implant healing and preserving the adhesion of hemidesmosomes to the titanium of MUA.

Novel technique using cold atmospheric plasma coupled with air-polishing for the treatment of titanium discs grown with biofilm: An in-vitro study.

OBJECTIVES: The aim of the present study was to assess the decontamination efficacy and titanium surface alterations of erythritol based air abrasion (AA) and cold atmospheric plasma (CAP) targeting a human complex biofilm. METHODS: Saliva collected from a peri-implantitis patient was used to develop in vitro human biofilm over titanium discs with machined (group A) and moderately rough (group B) surface. The discs were treated with AA, experimental CAP or a combination of both treatments (COM). The amount of biofilm on the discs was measured by crystal violet (CV). Surface features and roughness before and after treatment were assessed by SEM and laser profilometry, respectively. The data were statistically analyzed using Kruskal Wallis followed by Dunn's multiple comparison test after being checked for normality by Shapiro-Wilk test. RESULTS: All the discs in group A performed better to treatments compared to group B. In both groups, CV data showed significantly lower amount of biofilm after AA treatment compared to CAP (p<0.05). Cleaning efficacy revealed relevant decontamination of both the surfaces following AA and COM treatments and almost complete biofilm removal after AA application on group A (99.92%). SEM analysis demonstrated no post-treatment alterations on the discs and laser profilometry did not show statistically significant changes in Sa and Sdr values. SIGNIFICANCE: Decontamination with AA delivering erythritol with or without CAP is highly effective in biofilm removal from different titanium surfaces. All the tested treatments, including CAP showed no noticeable alterations of the titanium discs surface features. Further in vivo studies are necessary to understand the potential of CAP technology in implant surface decontamination.

Effectiveness of Manual Toothbrushing Techniques on Plaque and Gingivitis: A Systematic Review.

PURPOSE: Currently, there is no consensus on recommendations for manual toothbrushing techniques between dentists, oral health therapists and dental companies. The aim of this systematic review is to identify and assess the quality of evidence of the effectiveness of manual toothbrushing techniques in the existing literature. METHODS: A broad search was conducted on the electronic databases Medline via Ovid, PubMed and EBSCO Dentistry & Oral Sciences. Included studies examined manual toothbrushing technique efficiency. Articles were assessed utilising the Cochrane Collaboration's tool for assessing risk of bias. Thirteen studies met the inclusion criteria and were included in this review. These included five randomised controlled trials (RCT), seven experimental non-randomised control studies and one in vitro study. RESULTS: Of the 3190 articles identified, 40 were relevant to manual toothbrushing and 13 were included in the final review. Studies indicating statistically significantly superior plaque removal for a given technique were Bass (one), modified Bass (one), Charter's (two), Fones (two), scrub (two), roll (one), modified Stillman (one), toothpick method (one). Four studies exhibited no statistically significant difference in effectiveness of plaque removal. Unfortunately, considerable variation was found between studies, making a definitive conclusion impossible in terms of an ideal manual toothbrushing technique that would promote plaque removal and reduce gingivitis. CONCLUSION: There is still insufficient evidence for suggesting that one toothbrushing method is more effective than another in plaque removal and reduction of gingivitis. Excessive variability in many aspects of the design and methodology of the selected studies hinder conclusions on an ideal manual toothbrushing technique. Experimental randomised controlled trials that follow the CONSORT guidelines are required to provide adequate-quality evidence and make any definitive conclusions on the relative effectiveness of manual toothbrushing techniques.

The Emerging Role of Cold Atmospheric Plasma in Implantology: A Review of the Literature.

In recent years, cold atmospheric plasma (CAP) technologies have received increasing attention in the field of biomedical applications. The aim of this article is to review the currently available literature to provide an overview of the scientific principles of CAP application, its features, functions, and its applications in systemic and oral diseases, with a specific focus on its potential in implantology. In this narrative review, PubMed, Medline, and Scopus databases were searched using key words like "cold atmospheric plasma", "argon plasma", "helium plasma", "air plasma", "dental implants", "implantology", "peri-implantitis", "decontamination". In vitro studies demonstrated CAP's potential to enhance surface colonization and osteoblast activity and to accelerate mineralization, as well as to determine a clean surface with cell growth comparable to the sterile control on both titanium and zirconia surfaces. The effect of CAP on biofilm removal was revealed in comparative studies to the currently available decontamination modalities (laser, air abrasion, and chlorhexidine). The combination of mechanical treatments and CAP resulted in synergistic antimicrobial effects and surface improvement, indicating that it may play a central role in surface "rejuvenation" and offer a novel approach for the treatment of peri-implantitis. It is noteworthy that the CAP conditioning of implant surfaces leads to an improvement in osseointegration in in vivo animal studies. To the best of our knowledge, this is the first review of the literature providing a summary of the current state of the art of this emerging field in implantology and it could represent a point of reference for basic researchers and clinicians interested in approaching and testing new technologies.

N-Glycosylation profiling of intact target proteins by high-resolution mass spectrometry (MS) and glycan analysis using ion mobility-MS/MS.

Glycosylation influences the structure and functionality of glycoproteins, and is regulated by genetic and environmental factors. The types and abundance of glycans on glycoproteins can vary due to diseases such as cancer, inflammation, autoimmune and neurodegenerative disorders. Due to the crucial role glycans play in modulating protein function, glycosylation analysis could lead to the discovery of novel biomarkers and is of prime importance in controlling the quality of glycoprotein biopharmaceuticals. Here, we present a method for the identification and quantification of glycoforms directly on intact proteins, after immunoaffinity purification from biological fluids. The method was validated and applied to serum transferrin and the biopharmaceutical trastuzumab. The accuracy of the method, expressed as the relative error (RE), ranged from 2.1 (at high concentrations) to 7.9% (at low concentrations), and intra- and inter-day precision, expressed as relative standard deviation (RSD), was 3.2 and 8.2%, respectively. The sensitivity and linearity of the method were suitable for serum analysis and the LOQ was calculated to be 3.1 and 4.4 µg mL-1 for transferrin (TFN) and trastuzumab (TRA), respectively. Its application to transferrin from five healthy human serum samples yielded concentrations between 1.61 and 3.17 mg mL-1, which are in agreement with blood reference levels. In parallel, the structure of the identified glycans was determined by ion mobility spectrometry coupled with tandem mass spectrometry. No chromatographic separation was required and sample preparation was performed in a semi-automatic manner, facilitating the handling of up to 12 samples at a time. This method should be useful for clinical laboratories and for the quality control of large batches of biopharmaceuticals.