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Secondary organic aerosol (SOA) is formed in the atmosphere through the oxidation and condensation of organic compounds. Intermediate volatility compounds, compounds with effective saturation concentration (C*) at 298 K between 103 and 106 μg m-3, have high SOA yields and can be important SOA precursors. The first efforts to simulate IVOCs in chemical transport models (CTMs) used the volatility basis set (VBS), a highly parametrized scheme that oversimplifies their chemistry. In this work we propose a more detailed approach for simulating IVOCs in CTMs, treating them as lumped species that retain their chemical characteristics. Specifically, we introduce four new lumped species representing large alkanes, two lumped species representing polyaromatic hydrocarbons (PAHs) and one species representing large aromatics, all in the IVOC range. We estimate IVOC emissions from road transport using existing estimates of volatile organic compound (VOC) emissions and emission factors of individual IVOCs from experimental studies. Over the European domain, for the simulated period of May 2008, estimated IVOC emissions from road transport were about 21 Mmol d-1, a factor of 8 higher than emissions used in previous VBS applications. The IVOC emissions from diesel vehicles were significantly higher than those from gasoline ones. SOA yields under low-NOx and high-NOx conditions for the lumped IVOC species were estimated based on recent smog chamber studies. Large cyclic alkane compounds have both high yields and high emissions, making them an important, yet understudied, class of IVOCs., Manavi, S. E. I. and Pandis, S. N.: A lumped species approach for the simulation of secondary organic aerosol production from intermediate-volatility organic compounds (IVOCs): application to road transport in PMCAMx-iv (v1.0), Geosci. Model Dev., 15, 7731–7749, https://doi.org/10.5194/gmd-15-7731-2022, 2022

Additional file 1: Supplementary Table 1. Electronic databases searched (first search).

Purpose To evaluate the residual surface roughness of 5 common diamond-coated interproximal reduction (IPR) systems after consecutive in vitro applications in relation to system, diamond grain size, and instrument thickness. Methods IPR was performed on 80 extracted human incisors using motor-driven strips and discs under predefined conditions. The IPR auxiliaries were applied at 5 consecutive sessions of 20 s on intact interproximal surfaces, and the surface profile (Ra, Rz, Rmax) was analyzed at baseline and after each session with an optical profilometer. Results No overall significant difference in the roughness values was found between systems (P = 0.07 for Ra, P = 0.33 for Rz, and P = 0.48 for Rmax). There was a significant average decrease of Ra, Rz, and Rmax for all systems for every unit increase in time by −0.171 μm (P 0.05], −0.244 μm [P > 0.05], and −0.179 μm [P > 0.05], respectively). There was no evidence of interaction between system and time as the P values for Ra, Rz, and Rmax were 0.88, 0.51, and 0.70, respectively. Conclusions All IPR materials presented significant gradual decrease of surface roughness after repeated applications. There were no significant roughness changes among auxiliaries of different grain sizes. Thinner auxiliaries showed significantly more roughness reduction, possibly requiring more frequent replacement than thick auxiliaries in clinical practice.

Supplemental material, sj-docx-1-jdr-10.1177_00220345211025242 for Early Optimistic Effect in Periodontology and Implant Dentistry Trials by M.C. Menne, G. Seitidis, C.M. Faggion, D. Mavridis and N. Pandis in Journal of Dental Research

Aim: To assess the prevalence of a priori power calculations in orthodontic literature and to identify potential associations with a number of study characteristics, including journal, year of publication and statistical significance of the outcome. Materials and methods: The electronic archives of four leading orthodontic journals with the highest impact factor (American Journal of Orthodontics and Dentofacial Orthopedics, AJODO; European Journal of Orthodontics, EJO; Angle Orthodontist, ANGLE; Orthodontics and Craniofacial Research, OCR) were assessed over a 3 year period until December 2018. The proportion of articles reporting a priori power calculations were recorded, and the association with journal, year of publication, study design, continent of authorship, number of centres and researchers, statistical significance of results and reporting of confidence intervals (CIs) was assessed. Univariable and multivariable regression were used to identify significant predictors. Results: Overall, 654 eligible articles were retrieved, with the majority published in the AJODO (n = 246, 37.6%), followed by ANGLE (n = 222, 33.9%) and EJO (n = 139, 21.3%). A total of 233 studies (35.6%) presented power considerations a priori along with sample size calculations. Study design was a very strong predictor with interventional design presenting 3.02 times higher odds for a priori power assumptions compared to observational research [odds ratio (OR): 3.02; 95% CIs: 2.06, 4.42; P < 0.001]. Conclusions: Presentation of a priori power considerations for sample size calculations was not universal in contemporary orthodontic literature, while specific study designs such as observational or animal and in vitro studies were less likely to report such considerations. © 2019 The Author(s).

Purpose: To evaluate the residual surface roughness of 5 common diamond-coated interproximal reduction (IPR) systems after consecutive in vitro applications in relation to system, diamond grain size, and instrument thickness. Methods: IPR was performed on 80 extracted human incisors using motor-driven strips and discs under predefined conditions. The IPR auxiliaries were applied at 5 consecutive sessions of 20 s on intact interproximal surfaces, and the surface profile (Ra, Rz, Rmax) was analyzed at baseline and after each session with an optical profilometer. Results: No overall significant difference in the roughness values was found between systems (P = 0.07 for Ra, P = 0.33 for Rz, and P = 0.48 for Rmax). There was a significant average decrease of Ra, Rz, and Rmax for all systems for every unit increase in time by −0.171 μm (P < 0.001), −3.297 (P ≤ 0.001), and −2.788 μm (P = 0.001), respectively. Ra, Rz, and Rmax values increased significantly, i.e., by 0.194 μm (P = 0.003), 5.890 μm (P = 0.001), and 5.319 μm (P = 0.010) as instrument thickness increased by one unit. No significant reductions in Ra, Rz, and Rmax were observed across grain sizes (−0.008 μm [P > 0.05], −0.244 μm [P > 0.05], and −0.179 μm [P > 0.05], respectively). There was no evidence of interaction between system and time as the P values for Ra, Rz, and Rmax were 0.88, 0.51, and 0.70, respectively. Conclusions: All IPR materials presented significant gradual decrease of surface roughness after repeated applications. There were no significant roughness changes among auxiliaries of different grain sizes. Thinner auxiliaries showed significantly more roughness reduction, possibly requiring more frequent replacement than thick auxiliaries in clinical practice.

Background: It has been proposed that the threshold of statistical significance should shift from P-value

Purpose: To systematically review the evidence of the diagnostic efficacy of panoramic radiographs (PRs) in the following six clinical situations: caries, acute dental infections, dental trauma, dental anomalies, Developmental disorders and pathological conditions in children. The research question posed by the EAPD was: “In which clinical situations and age groups is it indicated/contra-indicated to prescribe PRs in relation to these six clinical situations, in children”. Methods: An electronic search of the following databases was conducted: MEDLINE via OVID, EMBASE via OVID, The Cochrane Oral Health Group’s Trials Register, the Cochrane Central Register of Controlled Trials (CENTRAL), The Cochrane Database of Systematic Reviews (CDSR), the Database of Abstracts of Reviews of Effects (DARE) and the Cochrane Health Technology Assessment (HTA), to identify relevant studies published from 1990 to 2018. The systematic review was performed according to the PRISMA guidelines. Study screening, data extraction and risk of bias assessment of included studies was carried out independently and in duplicate using the QUADAS 2 tool. Results: The search resulted in 3420 potentially relevant studies, and following screening 175 full texts were obtained, of which 16 were finally included in the review. Meta-analysis was not possible for any of the aforementioned clinical situations, therefore the included studies were tabulated in terms of qualitative descriptive hierarchy of evidence for diagnostic. Conclusion: Based on currently available evidence there is a need for high quality diagnostic accuracy efficacy studies to address important diagnostic tasks in these six clinical situations in children, as there is a lack of scientific evidence concerning PRs in children, as there would support the production of guidelines for prescribing PRs in children along with their relative indications and contra-indications. © 2019, European Academy of Paediatric Dentistry.

Research waste is highly prevalent across biomedical investigations. We aimed to assess the evidence on the extent of research waste in dental research. We performed a scoping review of empirical evaluations of dental studies assessing the prevalence and impact of limitations in design, conduct, analysis, and reporting of research. PubMed was searched using specific terms to retrieve studies dealing with design, conduct, analysis, and reporting of studies in dentistry, with no year or language restrictions. Of the 1,807 publications identified from the search and from manual searches, 71 were included in this review. The topic and article selection was based on the expert opinion of the authors. The existing evidence suggests that, although there are improvements over time, substantial deficiencies in all areas (design, conduct, analysis, reporting) were prevalent in dental research publications. Waste in research is a multifaceted problem without a simple solution. However, an appreciation of optimal research design and execution is a prerequisite and should be underpinned by policies that include appropriate training in research methods and properly aligned incentives.

Objectives: To study the oral health of young individuals with controlled and uncontrolled type 1 diabetes mellitus (T1DM) and compare the results with those for healthy counterparts. Materials and Methods: One-hundred and forty-four youngsters (6–15 years of age) were assigned, according to glycaemic control, to three study groups: (i) diabetic patients with poor glycaemic control [glycated haemoglobin (HbA1c ≥7.5%)] (n = 35); (ii) diabetic patients with good glycaemic control (HbA1c 0.05). Candida albicans levels were not statistically significant different among groups, but the group with poor glycemic control showed an elevated frequency of detection. Streptococcus mutans was isolated from the oral cavity of 96 of the 144 individuals. A statistically significant difference in the level of S. mutans was found between the group with poor glycaemic control and the healthy control group (P = 0.032). Conclusions: The results imply that youngsters with T1DM have a lower level of oral hygiene and are potentially at a higher risk of future oral disease, particularly when their metabolic disorder is uncontrolled. However, factors outside the oral cavity may also have a considerable impact on the initiation and progression of oral diseases. © 2019 FDI World Dental Federation

Background/objectives To assess the prevalence of within-group comparisons from baseline to follow-up in published orthodontic articles and to identify potential associations between this statistical problem and a number of study characteristics. Materials/method The most recent 24 issues of four leading orthodontic journals with highest impact factor (American Journal of Orthodontics and Dentofacial Orthopedics; AJODO, European Journal of Orthodontics; EJO, Angle Orthodontist; ANGLE, Orthodontics and Craniofacial Research; OCR) were electronically searched until December 31st 2017. The proportion of articles using comparisons against baseline and interpretation of findings according to within-group comparisons were recorded. The association of this practice with journal, year of publication, study design, continent of authorship, number of centres and researchers, statistical significance of results, and statistical analysis was tested. Univariable and multivariable modified Poisson regression were used to identify significant predictors. Results Overall, 339 articles were eligible for inclusion with the majority published in ANGLE (n = 157, 46%), followed by AJODO (n = 75, 22%), and EJO (n = 75, 22%). A total of 60 studies (18%) presented interpretation of their findings based on within-group comparisons against baseline in isolation. Statistical significance of the primary outcome was a very strong predictor of the prevalence of this flawed approach (RR: 2.33, 95% CIs: 1.22, 4.43; P = 0.01). Limitations The effect of time since publication was not addressed. Conclusions/implications Statistical testing and interpretation within groups is prevalent in orthodontic research. Endorsement of accurate conduct and reporting of statistical analyses and interpretation of research findings is important in order to promote optimal inferences to support clinical decision-making. © 2018 The Author(s). Published by Oxford University Press on behalf of the European Orthodontic Society. All rights reserved.

Background/Objectives: The aim of this study was to identify outcome-related discrepancies between registry trial entries and final published reports in orthodontic randomized controlled trials (RCTs). The percentage of registered orthodontic RCTs was also recorded. Materials/Method: Five trial registries, ClinicalTrials.gov (https://clinicaltrials.gov/), International Standard Randomised Controlled Trial Number registry (http://www.isrctn.com/), European Union Clinical Trials Register (https://www.clinicaltrialsregister.eu/), Australia New Zealand Clinical Trials Registry (http://www.anzctr.org.au/) and Clinical Trials Registry of India (www.ctri.nic.in/) were searched up to April 2018 in order to identify completed orthodontic RCTs. The unique trial identifier, the title and authors name were used to search for publications based on entries within Google (https://www.google.com), Google Scholar (https://scholar.google.gr/) and MEDLINE via PubMed (https://www.ncbi.nlm.nih.gov/pubmed/). Outcome reporting discrepancies and a number of other entry/publication characteristics were recorded including timing of registration, type of journal/ publication, significance of the primary outcome in the final report. The number of trials registered among the total number of published RCTs in orthodontics was recorded within the time span assessed. Results: One hundred and twenty-four entries were identified for completed orthodontic RCTs, whereas 53 of those were related to published final reports. Outcome reporting discrepancies were ascertained for 47 per cent of publications (n = 2 5); discrepancies were more prevalent for non-primary outcomes (n = 21, 40 per cent). Only 16 per cent of the published orthodontic RCTs had been registered. Limitations: Only a subset of trial entries were assessed as these were related to publication records. Conclusions/Implications: Registration of clinical trials in orthodontics remains far from universal. A significant level of outcome reporting discrepancy was observed within this subset of registered trials. © The Author(s) 2018. Published by Oxford University Press on behalf of the European Orthodontic Society. All rights reserved.

Background: Correction of dentofacial deformities via orthodontics is an integral part of oral health as promotes optimal function, periodontal health, aesthetics and overall oral health-related quality of life. The aim of this study was to examine whether paediatricians examine their patients to orthodontists, whether they have sufficient knowledge in basic orthodontic principles and whether they refer their patients for orthodontic abnormalities. Results: We conducted a survey study of paediatricians in Greece. Questionnaires were completed by 96 out of 123 paediatricians (response rate 78%). In the assessment of the examination of the oral cavity, a low frequency of examination of the position of the teeth (54%) and jaws (51%) was found. Reasons paediatricians referred patients to specialists varied from mouth breathing-snoring 24% (23/96) to face or teeth asymmetry 87% (84/96). In the multivariable analyses for the effect of gender, work sector or years of experience in the decision for orthodontic referral, we could not identify any significant predictors. Conclusions: The results of this study indicate that there was variability regarding orthodontic knowledge among paediatricians. Although the majority were aware of the importance of examination of the oral cavity, they did not have the appropriate knowledge to perform a full and systematic screening for orthodontic problems. The probability of referral was different for the various orthodontic anomalies. © 2019, The Author(s).

Purpose: The aim of this study was to evaluate the elemental and mechanical alterations of stainless steel (SS) multistranded orthodontic wires used in fixed retention after intraoral ageing. Materials and Methods: Two types of 0.022-inch, seven-stranded wires, Lingual Retainer Wire (LRW) and Tru-Chrome (TCH), from the same manufacturer (Rocky Mountain Orthodontics, Denver, Colo, USA) were tested. Thirty-three samples from LRW group and thirty-seven from TCH were collected, whereas three unused wires from each package were used as controls. The median ageing time for LRW was 7.4 years and 8.4 for TCH. All samples were subjected to scanning electron microscope/X-ray energy dispersive spectroscopy analysis. Three spectra were taken from the surface of each wire and then all samples were used for the assessment of Martens hardness, indentation modulus (EIT), and elastic index (ηIT) with the instrumented indentation testing method (IIT). The intraoral ageing time was statistically compared between the two groups by Mann-Whitney rank sum test and the compositional and mechanical properties were compared by unpaired t-test. The Spearman correlation between elemental content and ageing time was carried out for all elements (a = 0.05). Results: No significant differences were found for both the elemental content and for the mechanical properties between the wires tested. Spearman analysis revealed no correlation between elemental content and intraoral time while two groups share statistically equal intraoral ageing times (P > 0.05). Conclusions: Both wires seemed to maintain their mechanical and elemental integrity within a period of 14-year intraoral exposure, whereas no measurable ionic release could be identified. © The Author(s) 2017. Published by Oxford University Press on behalf of the European Orthodontic Society. All rights reserved.

Objectives: Heterogeneity describes the percentage of variability across the study effects that can be attributed to between-study differences in a meta-analysis. The aim of this project was to explore the magnitude of heterogeneity in Cochrane and non-Cochrane meta-analyses in orthodontic research and to identify possible associations between heterogeneity (I2) and a number of study characteristics including number of studies, type of outcome and type of analysis. Methods: The contents of five major orthodontic journals and the Cochrane Database of Systematic Reviews were electronically searched from January 2000 to December 2017 to identify Systematic Reviews (SRs) with at least one meta-analysis. Included records were screened for reporting of I2 classified into four categories: 0%, 1–29%, 30–59%, 60–100%. Associations between I2 and review-level and synthesis-level characteristics were tested. Univariable and multivariable mixed effects ordinal logistic regression was used to identify significant predictors for statistical heterogeneity. Results: A total of 72 SRs comprising 391 meta-analyses were included with the majority based on non-Cochrane reviews (n = 54, 75%). Overall, 125 meta-analyses (32%) reported heterogeneity explained by chance (I2 = 0%), whereas high values of I2 (∼60–100%) were seen in 152 syntheses (39%). In the multivariable analysis, inclusion of each additional study within the synthesis presented 20% higher odds for substantial/considerable heterogeneity compared to lower heterogeneity categories (OR = 1.20; 95%CIs: 1.09, 1.31; p < 0.001). Use of fixed effect analysis (OR = 0.25; 95%CIs: 0.12, 0.55; p = 0.001) was associated with significantly lower odds. Cochrane versus non-Cochrane meta-analyses were not associated with higher odds for substantial/considerable heterogeneity (OR = 2.81; 95%CIs: 0.53, 14.91; p = 0.22). Conclusions: Substantial statistical heterogeneity is present within a considerable number of orthodontic meta-analyses. Further efforts should be made to improve understanding of decisions to undertake meta-analyses and selection of studies eligible for inclusion. Clinical significance: The consistency of meta-analyses could be improved with more careful consideration of individual study characteristics. Reduced heterogeneity in meta-analyses will ensue more solid evidence based decisions for clinical practice © 2018 Elsevier Ltd

The purpose of this long-term follow-up study was twofold—firstly, to assess prevalence of relapse after treatment of deep bite malocclusion and secondly, to identify risk factors that predispose patients with deep bite malocclusion to relapse. Sixty-one former patients with overbite more than 50% incisor overlap before treatment were successfully recalled. Clinical data, morphometrical measurements on plaster casts before treatment, after treatment and at long-term follow-up, as well as cephalometric measurements before and after treatment were collected. The median follow-up period was 11.9 years. Patients were treated by various treatment modalities, and the majority of patients received at least a lower fixed retainer and an upper removable bite plate during retention. Relapse was defined as increase in incisor overlap from below 50% after treatment to equal or more than 50% incisor overlap at long-term follow-up. Ten per cent of the patients showed relapse to equal or larger than 50% incisor overlap, and their amount of overbite increase was low. Among all cases with deep bite at follow-up, gingival contact and palatal impingement were more prevalent in partially corrected noncompliant cases than in relapse cases. In this sample, prevalence and amount of relapse were too low to identify risk factors of relapse