POESIT recommendations on management of body-identical hormones in menopausal symptoms.

Many women seek treatment to improve menopausal vasomotor symptoms (VMS). The selection of women most likely to benefit from menopause hormone therapy (MHT) is crucial in clinical practice. There is general agreement that women younger than 60 years or who initiate MHT within the first 10 years of menopause, with no contraindications, have greater benefits considering symptomatic relief and additional advantages. This group may have the advantage of protection from osteoporosis and from other chronic diseases that affect postmenopausal women, namely cardiovascular disease (CVD). Cumulating evidence supports MHT for symptomatic women. However, inadequate use according to the needs of symptomatic women led to a burden of suffering worldwide. In recent years, the emergent use of non-regulated body-identical hormones (non-rBHT) can expose patients to potential harms. These hormone preparations are not regulated through the same tests of safety, efficacy or dosing consistency as regulated-BHT (r-BHT). The POESIT (Portugal + Spain + Italy) recommendations highlight the use of 17ß-estradiol (E2) and micronized progesterone (P4) as the real r-BHT. In addition, the group emphasizes as an example the data from the REPLENISH study with 1 mg E2/100 mg P4. The combination of the two hormones in one convenient pill showed a clear reduction or elimination of hot flashes and an improvement in sleep quality and, consequently, quality of life. At the same time, this combination has shown high rates of amenorrhea and no significant impact on lipid, glucose or coagulation parameters. Both the REPLENISH study and a real-life retrospective study pointed to the possibility of a lower risk of venous thromboembolism (VTE) with this formulation than with other combinations.

Perception of oral contraception - do women think differently from gynaecologists?

PURPOSE: This study aimed to assess the experience and satisfaction with contraceptives and use of Combined Oral Contraceptives (COC) by women and compare their perceptions with those of gynaecologists. METHODS: This was a multicentre survey study conducted in Portugal, during April and May, 2021 with women using contraceptives and gynaecologists. Online quantitative questionnaires were carried out. RESULTS: A total of 1508 women and 100 gynaecologists were included. Cycle control was the pill non-contraceptive benefit most valued by gynaecologists and women. For gynaecologists, the main pill concern was the risk of thromboembolic events, but they believed that weight gain was the main concern for their patients. The pill was the most used contraceptive (70%) and women were largely (92%) satisfied. The pill was associated with health risks for 85% of users, mainly thrombosis (83%), weight gain (47%), and cancer (37%). The attributes of the pill most valued by women are contraceptive efficacy (82%), followed by low risk of thromboembolic events (68%), good cycle control (60%), non-interference with libido and mood (59%) and weight (53%). CONCLUSION: Most women use contraceptive pills and are generally satisfied with their contraceptive. Cycle control was the most valued non-contraceptive benefit for gynaecologists and women, agreeing with physicians' beliefs about women. On the other hand, contrary to physicians' beliefs, that women's main concern is weight gain, women are mainly concerned with risks associated with contraceptives. Thromboembolic events are women's and gynaecologists most valued risk. Finally, this study indicates the need for physicians to better understand what COC users really fear.

Comparing women's perceptions with those of gynaecologists regarding Combined Oral Contraceptives, this study showed that contrary to physicians' beliefs, that women's main concern is weight gain, their main concern are risks associated with contraceptives. So, physicians need to better understand what women really fear.

Effect of lithium disilicate ceramic thickness, shade and translucency on transmitted irradiance and knoop microhardness of a light cured luting resin cement.

This in vitro study evaluates the influence of pressed lithium disilicate thickness, shade and translucency on the transmitted irradiance and the Knoop microhardness (KHN) of a light-cured resin cement at two depths. One hundred and thirty-five ceramic discs of IPS e.max Press (Ivoclar Vivadent) were fabricated and divided into twenty-seven groups (n = 5) according to the association between translucency: HT (hight translucency), LT (low translucency), and MO (medium opacity); shade: BL2, A1 and A3.5; and thickness: 0.5 mm, 1.5 mm, and 2.0 mm. One side of each ceramic disc was finished, polished and glazed. The irradiance (mW/cm²) of a multiwave LED light curing unit (Valo, Ultradent) was evaluated with a potentiometer (Ophir 10ª-V2-SH, Ophir Optronics) without (control group) or with interposition of ceramic samples. The microhardness of Variolink Esthetic LC resin cement (Ivoclar Vivadent) was evaluated after 24 h at two depths (100 µm and 700 µm). Data were submitted to ANOVA followed by Tukey's test (α = 0.05). Irradiance and KHN were significantly influenced by ceramic thickness (p < 0.0001), shade (p < 0.001), translucency (p < 0.0001) and depth (p < 0.0001). Conclusions: the interposition of increasing ceramic thicknesses significantly reduced the irradiance and microhardness of resin cement. Increased depth in the resin cement showed significantly reduced microhardness for all studied groups. Increased ceramic opacity reduced the KHN of the resin cement at both depths for all ceramic thicknesses and shades.

Influence of the organic matrix composition on the polymerization behavior and bulk properties of resin composites containing thiourethane-functionalized fillers.

OBJECTIVES: The incorporation of thiourethane-based oligomeric additives into resin composite formulations leads to improvement in mechanical properties and reduction in polymerization stress, but may increase viscosity. The objective of this study was to functionalize filler particle surfaces with thiourethane silane molecules and determine the impact of the inorganic filler loading and surface treatment on the behavior of experimental resin composites with systematically-varied organic matrices. METHODS: Thiourethane oligomer was synthesized de novo, and grafted to the surface of 0.7um barium glass. BisGMA and TEGDMA (BT) were combined (at 30:70, 50:50 or 70:30 wt%) to 50 or 75 wt% of methacrylate (MA-Sil - control) or thiourethane-silanized (TU-Sil) particles. Composites were made polymerizable by the addition of 0.2 wt% BAPO and 0.05 wt% BHT was added as inhibitor. A mercury arc lamp (320-500 nm) at 800 mW/cm2 was used for all curing procedures. Kinetics of polymerization was assessed by near-IR spectroscopy in real time. Polymerization stress was determined with a cantilever system in real time (Bioman). Flexural modulus and strength were determined in 3-point bending (25x2x2 mm). Water sorption and solubility and film thickness were tested according to ISO 4049. Polymeric network characteristics were analyzed by dynamic mechanical analysis (DMA). Data was analyzed with two-way ANOVA/Tukey's test (95%). RESULTS: Viscosity increased with the increase in BisGMA and/or filler amounts. Overall, TU-Sil containing composites showed delayed vitrification and higher final DC. Filler concentration did not affect DC neither flexural strength. DC decreased with increasing BisGMA content. Polymerization stress reduced and flexural modulus increased for higher filler content, especially for formulations containing TU-Sil particles. The water stability was positively affected by the increase in amount of BisGMA and inorganic filler particles. In terms of polymeric network, the addition of TU-Sil particles increased the Tg and decreased the E' and cross-link density. CONCLUSIONS: With the exception of flexural modulus, all tested properties were significantly impacted by the matrix viscosity and/or the addition of TU-Sil filler particles. In general, the use of thiourethane oligomers as a silane coupling agent was able to reinforce the materials and reduce the polymerization stress without negatively affecting the viscosity of the system.

Effect of radiotherapy, adhesive systems and doxycycline on the bond strength of the dentin-composite interface.

PURPOSE: To investigate the effect of radiotherapy, doxycycline and adhesive systems on the microtensile bond strength (µTBS) of the dentin-composite interface. METHODS: 60 human third molars were sectioned to expose middle dentin surface and distributed according to: (1) adhesive system (Adper Scotchbond MP and Clearfil SE Bond) applied, (2) application or not of doxycycline, and (3) submission to 60 Gy total radiation (2 Gy daily doses, 5 days/week for 6 weeks) before restoration procedure (RtRes); after restoration procedure (ResRt) or not submitted to radiotherapy (Control group). Specimens were tested for µTBS and mode of failure were evaluated under optical microscopy. The bonding interface was evaluated with a scanning electron microscope (SEM). Data was submitted to three-way ANOVA and Tukey's test (α= 0.05). RESULTS: There was no significant difference between the µTBS (MPa) of Adper Scotchbond MP (25.5±11.1) and Clearfil SE (27.6±9.1). Control (30.5±10.9) and ResRt (29.2±10.4) presented µTBS significantly higher than RtRes (23.1±7.2). Doxycycline (21.7±7.6) significantly reduced µTBS compared to groups without doxycycline application (33.6±8.6). Dentin cohesive failure mode was predominant for RtRes and mixed failure mode for ResRt. Mixed and adhesive failures were frequently observed in control groups. SEM showed adhesive penetration in dentin tubules in all groups, regardless of the radiotherapy and the application of doxycycline. The radiotherapy before composite restoration procedure decreased the µTBS. No statistical difference was observed between the adhesive systems. The doxycycline reduced µTBS regardless of the other conditions. CLINICAL SIGNIFICANCE: Composite restoration procedure should be done before radiotherapy, regardless of the adhesive system used.

Effect of hydrofluoric acid concentration and aging on the bond strength ceramics to a resin cement.

This study evaluated the influence of hydrofluoric acid (HF) concentration and thermal cycling on the microshear bond strength (µSBS) of a resin luting agent to IPS e.max® CAD and Rosetta® SM. Ceramic specimens (12.0 x 14.0 x 1.5mm) were randomized into 8 groups (n=10) according to HF concentration, commercial brand, and aging. Immediately after polishing, and etching, all specimens were silanized and a layer of adhesive was applied. A PVS mold of 3 mm thickness and 10mm diameter with (four) 1.0mm holes was fabricated, placed on each specimen, and then filled with a resin luting agent. Half of the specimens were subjected to the µSBS test using an Instron at a speed of 1.0 mm/min, following a 24-hour storage in deionized water at 37ºC. The remaining specimens were subjected to thermal cycling (5ºC-55ºC, 30 seconds per bath) and µSBS. The data were evaluated utilizing a three-way ANOVA and Tukey's post-hoc test (α=0.05). Significant differences were found for HF concentration and aging (p<0.0001). No significant difference in µSBS was found for commercial brands (p=0.085). The interaction between brand and HF concentration (p=0.358), brand and aging (p=0.135), and HF concentration and aging (p=0.138) were not statistically significant. The triple interaction among these factors was not statistically significant (p=0.610). In conclusion, the bond strength is affected by the HF concentration. No statistical difference was observed between the two ceramics. Thermal cycling significantly reduced µSBS.

Evaluation of mechanical properties and morphology of miniscrews Ti6Al4V cold worked versus annealed in artificial bones.

PURPOSE: This study aimed to evaluate the influence of different manufacturing procedures (Eli annealed - hot work versus cold worked - cold work) of the raw material under mechanical properties and morphological characteristics of orthodontic miniscrews (MS). MATERIAL AND METHODS: Thirty MS were randomly separated into 3 types (n=10) according to manufacturer and manufacturing process of the raw material: type A - SIN® annealed (control group); type B - Dentfix® annealed; and, type C - Dentfix® cold worked. MI were inserted in artificial bone blocks, through the manufacturer's specific manual key attached to the digital torquemeter stabilized via custom device. Data of fracture's occurrence was performed using Fisher's exact test. Comparisons between the other two types regarding insertion torque and removal torque were performed using the Mann-Whitney test. Data of fracture torque, shear stress, normal stress and torque ratio was submitted to Kruskal Wallis and Dunn tests (α=0.05). Representative images of surface morphology and fractures were selected. RESULTS: Type C showed statistically the lowest fracture torque (N.cm) (26.11±0.41) (P=0.0012) and highest torque ratio (%) (98.74±0.85) (P=0.0007). Type C showed statistically higher calculated shear (MPa) (2,432.73±508.41) and normal stress (MPa) (1,403.86±293.39) than type B and type A, showing that they differed in relation to the mechanical strength of the material with which they were made (P=0.0007). CONCLUSION: Type A fractured completely inside the most apical bone. Type B and type C fractured closer to the transmucosal profile. Cold worked process should be more prone to fractures than those annealed raw manufactured.

Cellulose acetate scaffold coated with a hydroxyapatite/graphene oxide nanocomposite for application in tissue engineering.

The objective of this study was to synthesize and characterize porous Cellulose Acetate (CA) scaffolds using the electrospinning technique and functionalize the surface of the scaffolds obtained through the dip-coating method with a Hydroxyapatite (HA) nanocomposite and varying concentrations of graphene oxide (GO) for application in tissue engineering regeneration techniques. The scaffolds were divided into four distinct groups based on their composition: 1) CA scaffolds; 2) CAHAC scaffolds; 3) CAHAGOC 1.0% scaffolds; 4) CAHAGOC 1.5% scaffolds. Scaffold analyses were conducted using X-ray Diffraction (XRD), Fourier Transform Infrared Spectroscopy (FTIR), Raman Spectroscopy, Scanning Electron Microscopy with Energy Dispersive Spectroscopy (SEM/EDS), and in vitro cell viability assays (WST). For the biological test analysis, Variance (two-way) was used, followed by Tukey's post-test (α = 0.05). The XRD results revealed the predominant presence of CaP phases in the CAHAC, CAHAGOC 1.0%, and CAHAGOC 1.5% groups, emphasizing the presence of HA in the scaffolds. FTIR demonstrated characteristics of cellulose and PO4 bands in the groups containing HA, confirming the presence of CaP in the synthesized materials, as also indicated by XRD. Raman spectroscopy showed the presence of D and G bands, consistent with GO, confirming the successful incorporation of the HAGO nanocomposite into the scaffolds. The micrographs displayed overlapping electrospun fibers, forming the three-dimensional structure in the produced scaffolds. It was possible to observe hydroxyapatite crystals filling some of these pores, creating a suitable structure for cell adhesion, proliferation, and nutrition, as corroborated by the results of in vitro tests. All scaffolds exhibited high cell viability, with significant cell proliferation. Even after 48 h, there was a slight reduction in the number of cells, but a noteworthy increase in cell proliferation was evident in the CAHAGOC 1.5% group after 48 h (p < 0.05). In conclusion, it can be affirmed that the produced scaffolds demonstrated physical and biological characteristics and properties capable of promoting cell adhesion and proliferation. Therefore, they represent significant potential for application in tissue engineering, offering a new perspective regarding techniques and biomaterials applied in regenerative therapies.

Effect of Ceramic Thickness on the Bond Strength to Resin-Luting Agents before and after Thermal Cycling.

This study investigated microshear bond strength (µSBS) of two (2) dual-cured resin-luting agents (RelyX™ Ultimate and RelyX™ U200) when photoactivated through varying thicknesses of lithium disilicate, with or without thermal cycling. Discs of IPS e.max Press of 0.5, 1.5, and 2 mm in thickness were obtained. Elastomer molds (3.0 mm in thickness) with four cylinder-shaped orifices 1.0 mm in diameter, were placed onto the ceramic surfaces and filled with resin-luting agents. A Mylar strip, glass plate, and load of 250 grams were placed over the filled mold. The load was removed and the resin-luting agents were photoactivated through the ceramics using a single-peak LED (Radii Plus.) All samples were stored in distilled water at 37oC for 24 h. Half of the samples were subjected to thermal cycling (3,000 cycles; 5ºC and 55ºC). All samples were then submitted to µSBS test using a universal testing machine (Instron 4411) at a crosshead speed of 0.5 mm/min. Data were submitted to three-way ANOVA and Tukey post-hoc test (α=0.05). The mean µSBS at 24 h was significantly higher than after thermal cycling (p<0.05). No statistical difference was found between resin-luting agents (p > 0.05). The mean µSBS for groups photoactivated through 0.5 mm ceramic were significantly higher than 1.5 mm and 2.0 mm (p < 0.05). In conclusion, increased ceramic thicknesses reduced the bond strength of tested resin-luting agents to lithium disilicate. No differences were found between resin-luting agents. Thermal cycling reduced the bond strength of both resin-luting agents.

Mycoplasma pneumoniae: a rare cause of vulvar ulcers or an undiagnosed one?

OBJECTIVES: Acute vulvar ulcers are quite common, and often, an etiological diagnosis cannot be achieved. This article reports 3 cases of vulvar ulcers in adult women infected with Mycoplasma pneumoniae. The authors were able to find only one similar report in the literature. MATERIAL AND METHODS: Two women in their third decade of life and 1 in the fourth presented to the hospital with acute and intense vulvar pain. Two of them reported oropharyngeal symptoms in the preceding days. All 3 presented with extensive, painful, and destructive vulvar ulcers. A standard protocol was applied, including samples taken from the ulcer (microbiology and polymerase chain reaction) and blood drawn for serological examination and liver function testing. All 3 had the remarkable finding of a positive immunoglobulin G (IgG) and IgM for M. pneumonia (in one of the cases, IgM was initially inconclusive but turned to positive when repeated 2 weeks later). One patient had an extensive destruction of one labium minus, requiring surgical reconstruction. RESULTS: Two of them were treated with antibiotics, and one was not. However, in fact, all 3 healed in a similar period, making it probable that this kind of medication is not helpful. CONCLUSIONS: M. pneumoniae might be associated with some cases of vulvar ulcers and should always be tested in this context. Probably, antibiotic treatment is not helpful, even when this agent is identified as the possible causal agent of vulvar ulcers.

Children and adolescents with non-Hodgkin lymphoma in Brazil: A national survey identifies the challenges encountered and documents the diversity of care.

INTRODUCTION: Brazil has many inequities in the healthcare provided nationwide. Therefore, in order to access challenges in treatment, available resources and current practices, to identify barriers in delivering a good quality of care among Brazilian centers treating children and adolescents with Non-Hodgkin Lymphoma (NHL) and to generate a future prospective guideline, a customized online survey was distributed to pediatric hematologists and oncologists across the country. RESULTS: A total of 97 surveys were completed (35% response rate), from 47 cities in all Brazilian regions and 79 units of care, with a median of 1 answer by the center (range 1 - 5). Most respondents work at an institution supported exclusively by public/philanthropic resources (58%), with an average of 5 to 9 new cases/year (49%), and 41% have 4 to 6 oncologists/centers. Additionally, 22% have no easy access to the intensive care unit, 26% have no access to Rasburicase, 28% have no access to Rituximabe as front-line therapy and 41% have unreliable methotrexate monitoring levels. Those differences cannot be explained thoroughly by regional wealth variances, nor by the financing model. Regarding the pathology service, 70% consider having reasonable quality assistance, but the timeframe to deliver diagnosis is satisfactory to 46%. There is no uniform management of care, with the current guideline from the Sociedade Brasileira de Oncologia Pediátrica being adopted by 54 to 59%, depending on the NHL subtype. CONCLUSION: This study provides insights into the heterogeneity of care among Brazilian centers. Recognizing those diversities will support the design of effective strategies and collaboration nationwide.

Deflection of tandem archwire in a specific self-ligating metal bracket system: an in vitro study.

The aim of this study was to quantify the force exerted by tandem archwires in a specific system of passive self-ligating bracket. Forty-eight thermo-activated nickel-titanium orthodontic archwires were separated into four groups (n = 12): G1 - two .014" + .014" round archwires; G2 - two .014" + .016" round archwires; G3 - .014" x .025" rectangular archwire; and. G4 - .016" x .022" rectangular archwire. Brackets were fixed onto teeth 1.5 to 2.5 using a device that represented the upper teeth, maintaining an interbracket distance of 6.0 mm. The deflection tests were performed using the structure representative of tooth 1.1 as support on the Instron testing machine at a speed of 2.0 mm/min. The archwires were evaluated at deflections of 0.5 mm, 1.0 mm, and 1.5 mm. The data were analyzed by a generalized linear model, considering values at different deflections as repeated measurements in the same experimental unit (α = 0.5%). At 0.5 mm, higher forces were observed in G2 and G3, which did not differ significantly (p > 0.05). The lowest force was observed in G4 (p < 0.05). At 1.0 mm and 1.5 mm, the highest force was observed in G3, followed by G4 and G2 (p < 0.05). The lowest force was observed in G1 (p < 0.05). In general, tandem archwires (same or different calibers) in a specific passive self-ligating bracket exerted lower force when compared with rectangular archwires.

Knowledge-attitude-practice survey among Portuguese gynaecologists regarding combined hormonal contraceptives methods.

ABSTRACT Objectives To evaluate knowledge, attitude and practices of Portuguese gynaecologists regarding combined hormonal contraceptives. Methods A cross-sectional survey was conducted among 303 gynaecologists. Results Ninety percent of the gynaecologists considered that deciding on contraceptive methods is a process wherein the woman has her say. Efficacy, safety and the woman's preference were the major factors influencing gynaecologists, while efficacy, tolerability and ease of use were the major factors perceived by the specialists to influence the women's choice. Gynaecologists believed that only 2% of women taking the pill were 100% compliant compared to 48% of those using the patch and 75% of those using the ring. The lower risk of omission was the strong point for the latter methods. Side effects were the main reason to change to another method. Vaginal manipulation was the most difficult topic to discuss. Conclusions Most gynaecologists decided with the woman on the contraceptive method. The main reasons for the gynaecologist's recommendation of a given contraceptive method and the women's choice were different. Counselling implies an open discussion and topics related to sexuality were considered difficult to discuss. Improving communication skills and understanding women's requirements are critical for contraceptive counselling.

Mechanical properties of cast commercially pure titanium simulating ceramic firing cycles.

AIM: To evaluate the mechanical properties (ultimate tensile strength, elongation and hardness) of the commercially pure titanium (cp Ti) as casting and after ceramic firing cycles. MATERIALS AND METHODS: Dumbbell-shaped specimens were prepared for the tensile strength testing. Disk-shaped cast specimens were used for microhardness testing. The ceramic firing cycles were made simulating a low fusion ceramic application. Tensile testing was conducted in a universal testing machine at a crosshead speed of 1 mm/min until failure. Ultimate tensile strength and elongation were recorded. The fracture mode was analyzed by scanning electron microscopy. Vickers hardness was measured in a hardness tester. The data from the tensile and hardness tests were subjected to a one-way analysis of variance and Tukey's test (α = 0.05). RESULTS: The mean values of tensile strength were not changed by the ceramic firing cycles. Lower hardness was observed for cp Ti as casting compared with Ti cast after the firing cycles. CLINICAL SIGNIFICANCE: The ceramic firing cycles did not show any considerable prejudicial effects on the mechanical properties of the cp Ti.

Comparison of the friction forces delivered by different elastomeric patterns and metal ligature on conventional metal brackets with a NiTi arch wire versus a self-ligating system: An in vitro study.

OBJECTIVES: The aim of this study was to measure the frictional resistance of different types of ligatures used on conventional and self-ligating brackets. MATERIALS AND METHODS: Monoblock (conventional) and Portia (self-ligating) brackets were used and the archwire used was nickel-titanium. On conventional brackets the ligatures tested were the Elastomeric type and steel 0.30 tie-wire. The groups were divided according to the ligature types (n=8): (1) conventional elastomeric ligature; (2) relaxed conventional elastomeric ligature; (3) elastomeric ligature in shape-8; (4) double vertical elastomeric ligatures; (5) double-crossed elastomeric ligatures; (6) crossed ligature; (7) steel wire ligature; and (8) self-ligating ligature (self-ligating bracket). A segment of five brackets, each ligature types, was mounted. The archwire, between the bracket and the ligature, was connected on Instron® Universal test machine to simulate the frictional resistance. The maximum frictional resistance was obtained, and the mean values were submitted to the analysis of variance (ANOVA) and the Tukey's post-hoc test (α=0.05). RESULTS: The elastomeric ligature in shape-8 showed the highest value compared with other groups (P<0.05). Although the crossed elastomeric ligature presented the lowest mean value and it was not statistically different regarding relaxed conventional elastomeric ligature, steel wire ligature and self-ligating (P≥0.05). CONCLUSIONS: The frictional resistance was influenced by ligature types. Elastomeric Ligature in shape-8 showed the highest frictional force. Crossed Elastomeric Ligature had the lowest frictional force value.

Effect of horizontal slot of maxillary canines' brackets with varying wire angulations - An in vitro study.

A new device was developed to enable the visualization and measurement of canine angulation while at the same time visualizing and measuring the force transmitted to adjacent teeth. This study aimed to evaluate the mesiodistal tilt angle of the upper canine brackets, the wire deflection, and its effects on adjacent teeth with five different slot designs of upper canines. Wires (0.020" and 0.019" x 0.025") were tested on different five bracket types at five different distal angles. The force applied to adjacent teeth was measured as the angle was increased, and its consequences were observed in the posterior and anterior regions as well. The force tension (gf) was measured in a universal testing machine. Data were submitted to a 3-way ANOVA and Tukey's test (α=0.05). For both arches, regardless of the type of tooth and bracket type, the highest means tension mean values were shown by the 20° angle, followed by the 15°,10°, and 5° angles, which differed statistically among themselves. Overall, for 5°, 10°, and 15° angles, conventional and versatile brackets showed significantly higher force values in all teeth, tip-edge and control brackets showed the lowest. The highest force values were observed in central and lateral incisors with conventional and versatile brackets and on first and second premolar teeth with self-ligating passive and control brackets. Conventional brackets presented the highest forces, tip-edge and control brackets showed the lowest. The teeth that suffered the greatest forces were lateral incisors, and those that suffered the least were second premolars.

Comparison of the shear bond strength between metal brackets and Transbond™ XT, Filtek™ Z250 and Filtek™ Z350 before and after gastroesophageal reflux: An in vitro study.

PURPOSE: To evaluate in vitro the effect of gastroesophageal reflux, before and after bonding of metal brackets on composite resin surface. MATERIALS AND METHODS: Two hundred and ten resin discs were divided into 5 groups (n=42), according to the time and medium of storage: 24h, 7- and -30 days in artificial saliva (AS) and hydrochloric acid (HCL). Twelve samples from each group were submitted to surface roughness analysis (n=60). The other one hundred and fifty samples were divided into 3 groups (n=50) according to the bonding material: Transbond™ XT (TXT), 3M™ Filtek™ Z250 (Z250) and 3M™ Filtek™ Z350 XT (Z350). After bonding, the samples were subdivided, one more time, into 5 groups (n=10) according to the time (24h, 7, and 30 days) and medium storage (AS, HCL). Following, the shear bond strength (SBS) analysis was accomplished. Erosive challenge was performed for 7 or 30 days, before and after bonding of orthodontic brackets, for 1min, 4 times a day. SBS was performed in a universal testing machine (Instron) at 0.5mm/min. SBS data were subjected to two-way ANOVA and Tukey's test (α=0.05). RESULTS: TXT showed higher SBS values in all conditions (AS - 10.9±2.0 (24h); 10.5±4.9 (7 days); 9.4±2.2 (30 days); HCL - 11.5±3.7 (7 days); 8.0±2.1 (30 days)) - (P<0.0001). No statistical difference was detected in SBS between Z250 and Z350 composite resins (Z250 SBS: AS - 7.1±1.9 (24h), 5.2±1.8 (7 days), 4.5±1.5 (30 days); HCL - 5.2±2.3 (7 days), 5.0±2.5 (30 days)) - (P<=0.063)/Z350 SBS: AS - 7.4±1.0 (24h); 3.7±1.7 (7 days); 3.4±1.7 (30 days); HCL - 3.5±3.3 (7 days); 4.4±1.2 (30 days)) - (P<=0.167), respectively). Storage times and media did not statistically influence the SBS of TXT and Z250 composite resins (P>0.05), but did influence the Z350 SBS (P<0.05). CONCLUSION: Regardless of time and storage medium, TXT was the best composite resin for bonding brackets. Furthermore, the erosive challenge did not lead to surface changes in the Z250 resin at 7 and 30 days, unlike the Z350 resin.

Comparison of the physico-chemical impact of chlorhexidine and silver nanoparticles on orthodontic appliances made with laser and silver solder: An in vitro study.

OBJECTIVE: The aim of this study was to evaluate the physical-chemical changes in orthodontic devices made with laser and silver solder after immersion in different antiseptic solutions. METHODS: Wire/band assemblies were fabricated using different types of solders (silver and laser). The devices were immersed in different antimicrobial solutions (chlorhexidine - CHX 0.12% and Silver nanoparticles - NAg 0.12% and 0.18%). Non-immersion in solution and immersion in artificial saliva were used as initial and negative control, respectively (n=12). Surface morphological analysis was performed using Scanning Electron Microscopy (SEM). The quantitative analysis of the chemical elements present after the immersions in the solutions was analysed by Energy Dispersive X-ray Spectroscopy (EDS). The data were subjected to the Kruskal-Wallis test followed by Bonferroni, with a significance level of 5%. RESULTS: Greater amounts of copper, silver and zinc were released from silver soldering, on the other hand, iron, nickel, and chromium ions were the most prevalent metal ions in laser soldering. Regarding mouthwashes, the lowest amounts of metal ions were released in CHX, and the highest amounts of ions were released in the 0.12% NAg and 0.18% NAg solutions. CONCLUSIONS: Laser welding seems to be less susceptible to corrosion. The different antiseptic solutions did not contribute to an increase in ion release.

Impact of a women's counselling programme on combined hormonal contraception in Portugal--the IMAGINE Study.

BACKGROUND: The aim of this health education project was to measure the impact of counselling about combined hormonal contraceptive (CHC) methods on the subsequent choice of method by Portuguese women. METHOD: This was a multi-centre study with a representative population, at the national and regional levels, of 2951 Portuguese women≥16 years of age visiting the gynaecologist. Counselling on available CHC methods was provided using a single leaflet, and their CHC choice was assessed before and after counselling. RESULTS: A combined oral contraceptive (COC) was the method preferred by the majority of the women prior to counselling. After counselling, 35% of women who initially had chosen the pill, switched to either the vaginal ring or the transdermal patch, and the difference was statistically significant. Ease of use was the major reason for choosing the COC, while a lower probability of omission was the reason for choosing the vaginal ring and the patch. CONCLUSIONS: The implementation of a counselling programme significantly affected contraceptive choices leading in a number of cases to the selection of alternatives better suited to women's lifestyle. Age and educational level are socio-demographic factors which play an important role.

Toughening and polymerization stress control in composites using thiourethane-treated fillers.

Filler particle functionalization with thiourethane oligomers has been shown to increase fracture toughness and decrease polymerization stress in dental composites, though the mechanism is poorly understood. The aim of this study was to systematically characterize the effect of the type of filler surface functionalization on the physicochemical properties of experimental resin composites containing fillers of different size and volume fraction. Barium glass fillers (1, 3 and 10 µm) were functionalized with 2 wt% thiourethane-silane (TU-Sil) synthesized de novo and characterized by thermogravimetric analysis. Fillers treated with 3-(Trimethoxysilyl)propyl methacrylate (MA-Sil) and with no surface treatment (No-Sil) served as controls. Fillers (50, 60 and 70 wt%) were incorporated into BisGMA-UDMA-TEGDMA (5:3:2) containing camphorquinone/ethyl-4-dimethylaminobenzoate (0.2/0.8 wt%) and 0.2 wt% di-tert-butyl hydroxytoluene. The functionalized particles were characterized by thermogravimetric analysis and a representative group was tagged with methacrylated rhodamine B and analyzed by confocal laser scanning microscopy. Polymerization kinetics were assessed by near-IR spectroscopy. Polymerization stress was tested in a cantilever system, and fracture toughness was assessed with single edge-notched beams. Fracture surfaces were characterized by SEM. Data were analyzed with ANOVA/Tukey's test (α = 0.05). The grafting of thiourethane oligomer onto the surface of the filler particles led to reductions in polymerization stress ranging between 41 and 54%, without affecting the viscosity of the composite. Fracture toughness increased on average by 35% for composites with the experimental fillers compared with the traditional methacrylate-silanized groups. SEM and confocal analyses demonstrate that the coverage of the filler surface was not homogeneous and varied with the size of the filler. The average silane layer for the 1 µm particle functionalized with the thiourethane was 206 nm, much thicker than reported for traditional silanes. In summary, this study systematically characterized the silane layer and established structure-property relationships for methacrylate and thiourethane silane-containing materials. The results demonstrate that significant stress reductions and fracture toughness increases are obtained by judiciously tailoring the organic-inorganic interface in dental composites.