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Background: Bruxism has a multifactorial etiology, including the influence of sleep characteristics and chronotypes. Aim: To identify the pathways that influence the occurrence of probable sleep bruxism (PSB) and probable awake bruxism (PAB) in adolescents. Design: A total of 403 adolescents, aged 12–19 years, participated in the study. Parents/caregivers filled out a questionnaire about sociodemographic issues and the adolescent's health conditions, and the adolescents about sleep characteristics, occurrence of bruxism (based on previous study and the International Consensus of Bruxism), and chronotype (Circadian Energy Scale). Clinical examinations were performed. Statistical analysis included descriptive analysis and path analysis. Results: PSB and PAB are related to each other, with moderate and positive correlation (β =.390). Poor sleep quality and higher household income had a direct effect on both PSB (β = −.138; β =.123, respectively) and PAB (β = −.155; β =.116, respectively). Chronotype had a direct effect on PSB, in such a way that adolescents with a morningness chronotype tend to have PSB (β = −.102). Adolescents that drool on the pillow (β =.184) and/or have agitated sleep (β =.104) tend to have PSB. Conclusion: Poor sleep quality, household income, morningness chronotype profile, drooling on the pillow, and agitated sleep influence the paths taken by PSB. PAB was influenced by the quality of sleep and family income. [ABSTRACT FROM AUTHOR]

This clinical trial investigated the effects of pre‐application enamel moistening on the impact of a 37% carbamide peroxide whitener on tooth color changes and the influence of repositioning guide colors. Forty participants were randomly assigned to in‐office tooth bleaching with either moistened enamel (experimental) or dry enamel (control). The whitener was applied for 45 min over two sessions. Tooth color was visually measured or assessed using a spectrophotometer with purple or green silicone guides. Tooth bleaching was assessed using CIE76 (ΔEab) and CIEDE2000 (ΔE00) formulas and by whitening and bleaching index score changes. Moistening the enamel did not significantly affect tooth color. However, the guide color choice only impacted tooth color when measured instrumentally. At baseline, the green guide resulted in statistically significantly whiter teeth than the purple guide. Less pronounced differences in the b* coordinate between baseline and final measurements were found using the green guide. The green guide also produced lower ΔEab values and less change in indexes. In conclusion, moistening the enamel did not significantly impact tooth color changes. However, the repositioning guide color influenced the tooth bleaching measured instrumentally, except for ΔE00. [ABSTRACT FROM AUTHOR]

Objective: This study assessed how the distance from the composite interface and the underlying chromatic substrate affect the color adjustment potential (CAP) of two single‐shade composites. Materials and Methods: Cylinder‐shaped specimens were created using Vittra APS Unique (VU), Charisma Diamond One (DO), and a shaded (A3) composite. Some single‐shade specimens were surrounded by the A3 composite, forming dual specimens. Color measurements of simple specimens were taken against a gray background using a spectrophotometer. All specimens were positioned at a 45° angle in a viewing booth under illuminant D65, and images were captured with a DSLR camera against gray or A3 backgrounds. Image colors were measured using image processing software and converted to CIELAB coordinates. Color differences (ΔE00) between the single‐shade composites and the A3 composite were calculated. CAP was determined by comparing data from simple and dual specimens. Results: No clinically significant differences were observed between color measurements obtained from images and the spectrophotometer. CAP was higher for DO compared to VU and increased as the distance from the composite interface decreased and when specimens were positioned against an A3 background. Conclusion: The color adjustment potential increased with decreased distance from the composite interface and against a chromatic background. Clinical Significance: Achieving satisfactory color match in restorations using single‐shade composites is crucial, and selecting an appropriate underlying substrate is essential. The color adjustment gradually decreases from the restoration margins towards its center. [ABSTRACT FROM AUTHOR]

Antibody‐drug conjugates (ADCs) are promising anticancer therapeutics, which offer important advantages compared to more classical therapies. There are a variety of ADC critical quality attributes (CQAs) such as the protein structure, aggregation, and drug‐to‐antibody ratio (DAR), which all impact on potency, stability, and toxicity. Production processes can destabilize antibodies via a variety of physical and chemical stresses, and or by increased aggregation after conjugation of hydrophobic drugs. Thus, a proper control strategy for handling, production, and storage is necessary to maintain CQA levels, which requires the use of in‐process quality measurements to first identify, then understand, and control the variables which adversely affect ADC CQAs during manufacturing. Here, we show how polarized excitation emission matrix (pEEM) spectroscopy, a sensitive, nondestructive, and potentially fast technique, can be used for rapidly assessing aggregation and DAR in a single measurement. pEEM provides several sources of information for protein analysis: Rayleigh scatter for identifying aggregate/particle formation and fluorescence emission to assess chemical and structural changes induced by attachment of a linker and/or a small molecule drug payload. Here, we used a nontoxic ADC mimic (monoclonal antibody with linker molecule) to demonstrate efficacy of the measurement method. Emission changes caused via light absorption by the attached linker, allowed us to predict DAR with good accuracy using fluorescence signal from the final purified products (6% relative error of prediction [REP]) and also from unpurified alkylation intermediates (11% REP). pEEM changes could also be correlated with size (hydrodynamic radius, Rh) and aggregate content parameters obtained from dynamic light scattering and size exclusion chromatography (SEC). For the starting material and purified product samples, pEEM correlated better with Rh (R2 = 0.99, 6% REP) than SEC determined aggregate content (18% REP). Combining both fluorescence and light scatter signals also enabled in‐process size quantification (6% REP). Overall, combining polarized measurements with EEM and Rayleigh scatter provides a single measurement, multi‐attribute test method for ADC manufacturing. [ABSTRACT FROM AUTHOR]

The present study aimed to determine how spectrophotometer type and background blackness affect the optical evaluation of resin composites. Cylindrical specimens were built using one resin composite, provided with translucencies named Effect, Enamel, Body, and Dentin (n = 3). The CIELAB color coordinates were assessed over black and white backgrounds using a handheld spectrophotometer designed for laboratory readings (SP60, X‐Rite) and a spectrophotometer designed for clinical application (Easyshade V5, Vita Zahnfabrik). The black portion of a grayscale target (ColorChecker) and the black trap portion of the calibration reference of the spectrophotometer were used. Color differences between the devices were calculated, as well as the translucency parameter and contrast ratio. Data were analyzed by repeated‐measures ANOVA and linear regressions (α =.05). In general, Easyshade resulted in higher values for all color coordinates than the SP60, irrespective of the background. Easyshade was unable to measure the color of composite Effect over black backgrounds. For other composite translucencies, both spectrophotometers yielded similar values of translucency parameter and contrast ratio, and the blackness of the black background did not affect these results. The highest agreement for the translucency parameter and contrast ratio values was observed for the composite Dentin. High agreement was observed between the two spectrophotometers regarding the translucency parameter and contrast ratio values. However, the clinical spectrophotometer was unable to measure the color of the more translucent composite over a black background and overestimated the color coordinates. [ABSTRACT FROM AUTHOR]

Objective: This in‐vitro study evaluated the color changes in enamel and dentin bleached in the presence of an orthodontic bracket, as well as the heterogeneity of the color and contribution of each tissue to the color change (CTCC). Materials and Methods: Enamel‐dentin specimens from extracted bovine teeth were bleached before or after bracket removal or maintained without any treatment (control). The colors of the dentin and enamel were measured individually and after recombining these substrates. The changes in the color (ΔE00) and whitening index (ΔWID) were estimated by the color difference between the bleached specimens and those of the control. The CTCC was also calculated by recombining the tissues from different treatments. Images of specimens obtained from a stereomicroscope were used to analyze the color homogeneity within each tissue. Results: The highest values of ΔE00 and ΔWID were observed in the specimens bleached in the absence of a bracket. Bleaching in the presence of a bracket resulted in enamel with a center that was whiter than the periphery. Dentin and enamel presented similar CTCC values. Conclusions: Tooth bleaching performed in the presence of a metallic bracket resulted in a reduced bleaching effect and increased color heterogeneity within both tissues. Clinical Significance: Tooth bleaching before the orthodontic bracket removal reduces the bleaching effect in both dentin and enamel. Moreover, a heterogeneous color of enamel surface can be observed after tooth bleaching in the presence of a nickel‐free metallic orthodontic bracket. [ABSTRACT FROM AUTHOR]

Aim: To assess the impact of two root canal treatment protocols on the oral health‐related quality of life (OHRQoL) of patients in need of root canal treatment on their anterior teeth. Methodology: The sample consisted of 120 participants (mean age: 34 years) enrolled in a pragmatic randomized clinical trial evaluating two root canal treatment protocols. Anterior teeth with nonvital pulps were allocated for root canal preparation with either hand files and filled with lateral compaction of gutta‐percha (manual protocol) or canal preparation with a single file in a reciprocating movement and filled with a single cone technique (Reciproc protocol). OHRQoL data were assessed using the Oral Health Impact Profile instrument (OHIP‐14), which was administered before the root canal intervention (baseline), and 6 and 12 months after treatment. Demographic and clinical characteristics of participants were collected at baseline. Data were analysed using bivariate analyses, Poisson univariate and multiple regression (α = 0.05). Results: The drop‐out rate from baseline was 27% and 28% at 6 and 12 months after treatment, respectively. Both root canal protocols significantly enhanced patients' OHRQoL, regardless of the follow‐up time (P < 0.001). After 6 months, patients treated with the Reciproc protocol had significantly lower OHIP‐14 overall scores (P = 0.030), as well as significantly lower scores for psychological discomfort (P = 0.031) and social disability (P = 0.013). After 12 months, no significant difference was observed between the two root canal protocols for OHIP‐14 overall scores (P = 0.174). Either large or moderate effect sizes were observed for all domains and overall scores at both evaluation times, irrespective of the protocol. Low‐income persons (RR = 2.03) and the Reciproc protocol (RR = 1.52) had a higher likelihood of a positive impact on OHRQoL 12 months after root canal treatment. Conclusions: The two root canal protocols improved the OHRQoL and differences in scores were observed only after 6 months with poorer OHRQoL for the manual protocol. After 12 months, patients with low‐income status and treated with Reciproc were associated with a greater improvement in OHRQoL scores. [ABSTRACT FROM AUTHOR]

Objective: This study evaluated the effects of adhesive type used as modeling liquid on the stability of the color and opacity of composites submitted to thermal cycling in staining solutions followed by a bleaching procedure. Methods: Thirty cylinder‐shaped composite specimens (10 mm diameter × 1.5 mm thickness) were built using or not using (control) an adhesive (Adper Universal or Scotchbond Multipurpose) as the modeling liquid. After polishing procedures, the color and opacity were measured, and the specimens were submitted to 200 thermal cycles with 10 s of dwell time in baths of grape juice at 5°C, water at 37°C, and coffee at 55°C. Changes in opacity and color caused by the staining solutions were measured. Then, the specimens were bleached with 35% hydrogen peroxide for 45 minutes followed by color/opacity measurements. Data were analyzed by ANOVA and Tukey's test (α = 0.05). Results: The use of modeling liquids did not affect the initial color and opacity of composite. Reduced changes to color (E00 = 3.44) and opacity (+2.67%) were observed for specimens modeled using Adper Universal. Bleaching procedures reduced the color (E00 = 1.9‐3.8) and opacity (−2.3 to 3.1%) alterations caused by staining solutions but were unable to restore the values observed at baseline. Conclusion: The use of universal adhesive as modeling liquid significantly reduced the color and opacity changes caused by staining solutions, and the bleaching procedure partially re‐established the opacity and color of the composites. Clinical Significance: This study evaluates whether using adhesive systems for modeling a composite affects the color and opacity changes caused by staining solutions followed by a bleaching procedure. The findings suggest that the use of a universal adhesive as modeling liquid can reduce the alterations in optical properties caused by staining solutions, and the application of high‐concentrated hydrogen peroxide over the composite reduce the color changes without fully recover the initial color. [ABSTRACT FROM AUTHOR]

Abstract: Background: Findings in regenerative medicine applied to the sinus lift procedures. Purpose: Evaluate the effectiveness of regenerative medicine in sinus lift. Materials and Methods: An extensive search for manuscripts were performed by using different combinations of keywords and MeSH terms (Pub‐med; Embase; Scopus; Web of Science Core Collection; Medline; Current Contents Connect; Derwent Innovations Index; Scielo Citation Index; Cochrane library). The full text selected articles are written in English, Portuguese, Spanish, Italian, German, or French, and published until 28 of November 2016. Inclusion criteria were: implant osteointegration, radiographic, histologic, and/or histomorphometric analysis, clinical studies in humans using of regenerative medicine. This systematic review was performed by selecting only randomized controlled clinical trials and controlled clinical trials. Results: Eighteen published studies (11 CT and 7 RCT) were considered eligible for inclusion in the present systematic review. These studies demonstrated considerable variation of biomaterial and cell technics used, study design, sinus lift technic, outcomes, follow‐up, and results. Conclusion: Only few studies have demonstrated potential of regenerative medicine in sinus lift; further randomized clinical trials are needed to achieve more accurate results. [ABSTRACT FROM AUTHOR]

Aim To evaluate the alterations promoted by a thermally deposited siloxane-methacrylate coating on the surface of glass fibre posts and their effect on the bond strength of resin-core materials to the posts. Methodology Fibre post surfaces were treated with experimental thermally deposited siloxane-methacrylate coatings or clinically available treatments (i.e. hydrogen peroxide and methylene chloride); nontreated posts were used as controls. The contact angles formed between the post surface and the water/adhesive were measured with a tensiometer. Scanning electron microscopy and electron dispersive spectroscopy were used to examine the topographies and chemical changes in the post surfaces following treatment. Surface roughness was evaluated with laser interferometry. Core resin was bonded to the fibre posts, and microtensile bond strength testing was subsequently performed. The data were individually submitted to anova and Tukey's tests (α = 0.05). Results The water contact angle was reduced significantly ( P < 0.05) by the thermally deposited siloxane-methacrylate coating. All treatments significantly increased the adhesive contact angle ( P ≤ 0.016) compared to the control as well as the surface roughness ( P ≤ 0.006) and the amount of Si on post surfaces. Greater percentages of Si were observed for the thermally deposited coating. The bond strength to the posts was significantly improved by the thermally deposited coating ( P < 0.05), whereas the other treatments did not differ from the control. Conclusion Treating the surface of glass fibre posts with a thermally deposited siloxane-methacrylate coating improved the bond strength to resin-based materials. The coating could be performed by manufacturers of glass fibre posts in order to reduce the number of clinical steps required for luting posts into root canals. [ABSTRACT FROM AUTHOR]

Aim To evaluate the effect of adhesive restorations on fracture resistance and stress distribution in teeth with simulated immature apices and apical plugs of mineral trioxide aggregate ( MTA). Methodology Sixty bovine incisors were sectioned 8 mm above and 12 mm below the cemento-enamel junction ( CEJ). The root canal was enlarged using a diamond bur, resulting in remaining root canal walls with 0.1-0.2 mm of thickness. A 5-mm apical plug of MTA was placed and the teeth were restored according to the following groups: GP - the root canal was filled with gutta-percha and endodontic sealer; CR - the root canal was filled with light-cured composite resin inserted incrementally; FP - a fibre post was cemented into the root canal; and RFP - the fibre post was relined with composite resin prior to the cementation into the root canal. A load was applied on the crown of all teeth at 135° to their long axis until fracture. Data was analysed by one-way anova and SNK tests (α = 0.05), whilst the fracture pattern was evaluated according to the position of the fracture. Stress distributions in the restored teeth were verified by finite element analysis. Results Teeth restored with fibre posts and relined fibre posts were associated with the highest fracture resistance, whilst the GP group had the lowest values. GP and RC groups had similar fracture resistance values ( P = 0.109). All fractures types involved the cervical and middle thirds of roots. The GP model had high levels of stress concentration in the cervical and middle thirds of roots. No difference was found amongst the stress concentration in the RC, FP and RFP models. Conclusion Restorative protocols alter the fracture resistance and stress distribution of immature teeth after placement of MTA apical plugs. [ABSTRACT FROM AUTHOR]

Aim To evaluate streaking artifacts produced by several root canal sealers on CBCT images with variations in voxel resolution. Methodology Single-rooted premolars were selected and root filled using gutta-percha cones and one of the following sealers: Endofill, Sealer 26, Fillapex or AH Plus. Root canals filled only with gutta-percha were used as control. Scans of teeth using a small-volume CBCT were performed, and the images acquired were evaluated by two calibrated observers (k > 0.75). Artifacts were identified as streaks and dark bands on root dentine in axial slices with 2 voxel sizes (0.076 and 0.2 mm). Fisher's exact test ( P < 0.05) was used to compare the presence/absence ratio of artifacts considering the factors 'sealer' and ' voxel size'. Results For the 0.20 mm voxel size, Sealer 26 had significantly more artifacts than Fillapex ( P = 0.006) or AH Plus ( P = 0.017). No differences existed between the sealers when the 0.07 mm voxel size was used. Sealer 26 ( P = 0.042) and Endofill ( P = 0.035) had significantly more artifacts in the 0.20 mm voxel size than with the 0.076 mm voxel size, whilst no difference was noted for other filling conditions. Conclusions The material used for root filling and the voxel resolution can influence the presence of streaking artifacts observed in CBCT images. [ABSTRACT FROM AUTHOR]

International Journal of Paediatric Dentistry 2011; 21: 314-320 Adhesive procedures are often required to restore teeth affected by hypocalcified amelogenesis imperfecta (HAI). To evaluate the hardness of enamel/dentin of teeth affected by HAI and the bond strength to these substrates, as well the influence of 5% NaOCl on bond strength. Permanent molars presenting HAI and sound third molars were used. Enamel surfaces were wet-flattened and Knoop hardness was assessed. The two-step, etch-and-rinse adhesive Single Bond 2 (3M ESPE) was applied and resin cylinders bonded to the surfaces and submitted to microshear testing. The subjacent medium dentin was then exposed by wet-grinding. Hardness readings and microshear testing were carried out again. The relationship between hardness and bond strength was assessed by nonlinear regression analysis. Hardness of normal enamel was higher than hardness of enamel affected by HAI, whereas dentin hardness did not differ from normal to HAI-affected teeth. Enamel and dentin hardness were similar for teeth affected by HAI. Higher bond strengths were obtained to the normal tooth tissues. Dentin bond strength was higher than enamel bond strength. NaOCl exposure did not influence bond strengths. A positive linear relationship between enamel hardness and bond strength was observed. HAI imposes challenges to bonding to enamel and dentin. [ABSTRACT FROM AUTHOR]

Background: Iodinated contrast media cause both immediate and nonimmediate hypersensitivity reactions. The aim of this prospective study was to determine the specificity and sensitivity of skin tests in patients who have experienced such reactions. Methods: Skin prick, intradermal and patch tests with a series of contrast media were conducted in 220 patients with either immediate or nonimmediate reaction. Positive skin tests were defined according to internationally accepted guidelines. Seventy-one never-exposed subjects and 11 subjects who had tolerated contrast medium exposure, served as negative controls. Results: Skin test specificity was 96–100%. For tests conducted within the time period from 2 to 6 months after the reaction, up to 50% of immediate reactors and up to 47% of nonimmediate reactors were skin test positive. For immediate reactors, the intradermal tests were the most sensitive, whereas delayed intradermal tests in combination with patch tests were needed for optimal sensitivity in nonimmediate reactors. Contrast medium cross-reactivity was more common in the nonimmediate than in the immediate group. Interestingly, 49% of immediate and 52% of nonimmediate symptoms occurred in previously unexposed patients. Many of these patients were skin test positive, indicating that they were already sensitized at the time of first contrast medium exposure. Conclusions: These data suggest that at least 50% of hypersensitivity reactions to contrast media are caused by an immunological mechanism. Skin testing appears to be a useful tool for diagnosis of contrast medium allergy and may play an important role in selection of a safe product in previous reactors. [ABSTRACT FROM AUTHOR]

Purpose: To propose alternative formulas for the sagitta calculation of ophthalmic lenses. Methods: Equation factoring. Results: The conventional sagitta formula is algebraically inconsistent when applied to curves with direction‐oriented radii. It is possible to correct this problem by factoring it. Conclusions: The conventional sagitta formula can and should be replaced by unambiguous equations. [ABSTRACT FROM AUTHOR]

Purpose: To evaluate the results of penetrating corneal transplantation at a university hospital in Brazil. Methods: A prospective cohort study was conducted on 146 patients who underwent penetrating keratoplasty at the University Hospital, Faculty of Medicine of Ribeirão Preto, University of São Paulo, Brazil. The participants were followed postoperatively for 36 months or until graft failure. Results: In this period, 49% of the grafts lost transparency. All the corneal diseases analysed were present in about the same proportions, except for keratoconus and bullous keratopathy, which showed 3% and 73% rates of graft oedema, respectively. Only 8% of the failures could be attributed to rejection. Other variables such as age, multiple surgeries and previous eye conditions could not explain the high rate of graft failure. Non-adherence to postoperative care increased with age, with a significant association between this behaviour and the rate of graft failure in the older age group. Keratoconus seems to be much less demanding and bullous keratopathy seems to be more exigent in terms of corneal transplantation than other corneal diseases. Conclusion: Although it involves an apparently simple surgical procedure, corneal transplantation is a demanding enterprise that can lead to very poor results under unfavourable conditions. [ABSTRACT FROM AUTHOR]

Numerous studies indicate that sleep deprivation alters energy expenditure. However, this conclusion is drawn from indirect measurements. In the present study, we investigated alterations of energy expenditure, body composition, blood glucose levels, plasma insulin, adrenocorticotropic hormone (ACTH) and corticosterone levels immediately after 4 days of sleep deprivation or after 4 days of sleep recovery. Rats were sleep deprived or maintained in a control environment (groups sleep-deprived/deprivation and control/deprivation). One half of these animals were sacrificed at the end of the deprivation period and the other half was transported to metabolic cages, where they were allowed to sleep freely (groups sleep-deprived/recovery and control/recovery). At the end of the sleep recovery period, these rats were sacrificed. After sleep deprivation, sleep-deprived rats exhibited loss of body weight, augmented energy expenditure and reduced metabolic efficiency compared to control rats. These alterations were normalised during the sleep recovery period. The body composition of sleep-deprived rats was altered insofar as there was a loss of fat content and gain of protein content in the carcass compared to control rats. However, these alterations were not reversed by sleep recovery. Finally, plasma levels of insulin were reduced during the sleep deprivation period in both control and sleep deprived groups compared to the recovery period. After the deprivation period, plasma ACTH and corticosterone levels were increased in sleep-deprived rats compared to control rats, and although ACTH levels were similar between the groups after the sleep recovery period, corticosterone levels remained elevated in sleep-deprived rats after this period. By means of direct measurements of metabolism, our results showed that sleep deprivation produces increased energy expenditure and loss of fat content. Most of the alterations were reversed by sleep recovery, except for corticosterone levels and body composition. [ABSTRACT FROM AUTHOR]

The objective of this work was to develop low fat orlightcakes by substituting the fat with either guar or xanthan gums. In order to measure the effect of this substitution, the following were evaluated: specific density of the dough, specific volume, moisture content, internal characteristics and the presence of moulds. Cakes with 25 and 50% substitution of the fat were also evaluated with respect to water activity (Aw), firmness and elasticity. The proximate composition analysis was used to determine the reductions in fat content and caloric value. Cakes with 50% substitution with guar and xanthan gums, up to 15 days storage, showed no significant difference (P < 0.05) with respect to firmness and elasticity. Therefore substitution of 50% of the normal fat content with gums allowed the production of cakes that werelightwith respect to their fat content. It was found that those made with xanthan gum were considered better with respect to overall appreciation and texture in the acceptability test. [ABSTRACT FROM AUTHOR]

This paper presents a three-step method for the addition of obliquely crossed spherocylinders. Contrary to other methods it does not require algorithms or complicated abstract concepts to secure the consistency of the results. [ABSTRACT FROM AUTHOR]

A letter to the editor is presented in response to the article "Cholesteryl ester transfer protein gene mutations in Brazilian hyperalphalipoproteinemia," published in the April 2006 issue of Clinical Genetics.

The available methods for the exact calculation of centre thickness presuppose that one knows simultaneously both surfaces of the lens and that the lens' power is determined afterwards. However, this approach is of secondary importance in practical situations. The issue in daily practice is the determination of the centre thickness of lenses that already have explicit vertex powers. In such cases one can set only one surface. The other has to be calculated following the prescription, the known surface and the optical effect of the centre thickness. Exact solution for this problem leads to four expressions, reflecting the number of ways one can treat it. Two of them are complete second-order algebraic equations and the other two, complete third-order algebraic equations. The practical value of the latter is limited by the fact that one cannot always obtain their three roots by pure algebraic procedures. [ABSTRACT FROM AUTHOR]

Thiourethane oligomers added to methacrylate matrices improve fracture toughness and reduce polymerization stress. In this study, the oligomers are added to the surface of inorganic fillers in the formulation of resin composites. Systematically varied fillers treated either with the thiourethane or a methacrylate silane control are tested. Thiourethane reduces the rate of polymerization of light‐cured composites but does not affect the final degree of conversion. Filler functionalization with thiourethane increases the depth of polymerization, in filler type‐dependent fashion. Thiourethane reduces the polymerization stress for all fillers. The findings suggest that this approach results in the same general effects with the addition of thiourethanes directly to the matrix. This is accomplished with a lower overall concentration of thiourethane, and with no prejudice to the handling characteristics of the material. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019, 136, 47687. [ABSTRACT FROM AUTHOR]

A letter to the editor is presented regarding the use of vitrectomy in the treatment of ocular toxoplasmosis.

The article presents the author's response on the comments on her article on the obliquely crossed spherocylindrical powers. The author noted that there is no method of lens' addition that is realistic if it does not consider the daily practice. She added that the method should conform to the needs of the practitioner, rather than the practitioner accommodating to the method.

The article presents the author's response on the comments on his article on the addition of obliquely spherocylindrical lenses. The author commented that the verification of the validity of the mathematical expression is instructive, but not fundamental. Meanwhile, it is noted that the method of finding the cylindrical power requires the two equations and instructions telling when to use one or another.

Background: Anaphylaxis, which is rare, has been reported after COVID-19 vaccination, but its management is not standardized., Method: Members of the European Network for Drug Allergy and the European Academy of Allergy and Clinical Immunology interested in drug allergy participated in an online questionnaire on pre-vaccination screening and management of allergic reactions to COVID-19 vaccines, and literature was analysed., Results: No death due to anaphylaxis to COVID-19 vaccines has been confirmed in scientific literature. Potential allergens, polyethylene glycol (PEG), polysorbate and tromethamine are excipients. The authors propose allergy evaluation of persons with the following histories: 1-anaphylaxis to injectable drug or vaccine containing PEG or derivatives; 2-anaphylaxis to oral/topical PEG containing products; 3-recurrent anaphylaxis of unknown cause; 4-suspected or confirmed allergy to any mRNA vaccine; and 5-confirmed allergy to PEG or derivatives. We recommend a prick-to-prick skin test with the left-over solution in the suspected vaccine vial to avoid waste. Prick test panel should include PEG 4000 or 3500, PEG 2000 and polysorbate 80. The value of in vitro test is arguable., Conclusions: These recommendations will lead to a better knowledge of the management and mechanisms involved in anaphylaxis to COVID-19 vaccines and enable more people with history of allergy to be vaccinated., (© 2022 EAACI and John Wiley and Sons A/S. Published by John Wiley and Sons Ltd.)

Objective: This in-vitro study evaluated the color changes in enamel and dentin bleached in the presence of an orthodontic bracket, as well as the heterogeneity of the color and contribution of each tissue to the color change (CTCC)., Materials and Methods: Enamel-dentin specimens from extracted bovine teeth were bleached before or after bracket removal or maintained without any treatment (control). The colors of the dentin and enamel were measured individually and after recombining these substrates. The changes in the color (ΔE 00 ) and whitening index (ΔWID) were estimated by the color difference between the bleached specimens and those of the control. The CTCC was also calculated by recombining the tissues from different treatments. Images of specimens obtained from a stereomicroscope were used to analyze the color homogeneity within each tissue., Results: The highest values of ΔE 00 and ΔWID were observed in the specimens bleached in the absence of a bracket. Bleaching in the presence of a bracket resulted in enamel with a center that was whiter than the periphery. Dentin and enamel presented similar CTCC values., Conclusions: Tooth bleaching performed in the presence of a metallic bracket resulted in a reduced bleaching effect and increased color heterogeneity within both tissues., Clinical Significance: Tooth bleaching before the orthodontic bracket removal reduces the bleaching effect in both dentin and enamel. Moreover, a heterogeneous color of enamel surface can be observed after tooth bleaching in the presence of a nickel-free metallic orthodontic bracket., (© 2020 Wiley Periodicals LLC.)

Herpetomonas roitmani, a non-pathogenic trypanosomatid was grown in chemically defined media either containing proline or glucose as carbon source. Using transmission electron microscopy we observed that cells grown in the presence of proline present more lipid inclusions, and a larger mitochondrion with more cristae and higher activity of succinate cytochrome c reductase. On the other hand, cells grown with glucose as carbon source had more glycosomes, which were preferentially located close to the bacterium endosymbiont, and a much higher activity of hexokinase, a typical glycosome marker. Three-dimensional reconstruction and morphometrical analysis confirm these observations. The number of promastigotes of H. roitmani increased in the presence of proline. Taken together these results indicate that the growth conditions markedly influenced the ultrastructure and the metabolism of H. roitmani.