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1.
Viruses ; 14(9)2022 08 30.
Article in English | MEDLINE | ID: mdl-36146731

ABSTRACT

Background: The present study aimed to examine longitudinal trends in hospitalizations for acute coronary syndrome (ACS) before and during the COVID-19 pandemic, by reviewing the data from 13 hospitals of the Veneto Region, in the north-east of Italy. Methods: We performed a multicenter, retrospective analysis including all the consecutive patients presenting with ACS and other acute cardiovascular (CV) conditions (defined as heart failure, arrhythmias, cardiac arrest and venous thromboembolism) hospitalized in 13 different hospitals of the Veneto Region covering a population of 2,554,818 inhabitants, during the first (between 15 March 2020 and 30 April 2020) and second (between 15 November 2020 and 30 December 2020) COVID-19 pandemic waves (the 2020 cohort). Data were compared with those obtained at the same time-windows of years 2018 and 2019 (the historical cohorts). Results: Compared to the historical cohorts, a significant decrease in the number of ACS cases was observed in 2020 (−27.3%, p = 0.01 and −32%, p < 0.001, comparing 2018 versus 2020 and 2019 and 2020, respectively). The proportion of patients hospitalized for acute CV conditions decreased during the first and second wave COVID-19 pandemic when compared to the historical cohorts (−36.5%, p < 0.001 and −40.6%, p < 0.001, comparing 2018 versus 2020 and 2019 and 2020, respectively). Pearson's correlation evidenced a significant inverse relationship between the number of COVID-19 cases and both ACS hospital admissions (r = −0.881, p = 0.005) and hospitalizations for acute CV conditions (r = −0.738, p = 0.01), respectively. Conclusions: The decrease in hospitalizations for ACS and other acute CV conditions will strongly affect future patients' management since undiagnosed nonfatal CV events represent a source of increased (and unknown) CV morbidity and mortality.


Subject(s)
Acute Coronary Syndrome , COVID-19 , Cardiovascular Diseases , Acute Coronary Syndrome/diagnosis , Acute Coronary Syndrome/epidemiology , Acute Disease , COVID-19/epidemiology , Cardiovascular Diseases/epidemiology , Hospitalization , Humans , Pandemics , Retrospective Studies
2.
Viruses ; 14(9)2022 09 06.
Article in English | MEDLINE | ID: mdl-36146778

ABSTRACT

Background: During the COVID-19 pandemic, the risk of SARS-CoV-2 infection, the public health measures of social distancing, the freedom limitations, quarantine, and the enforced homeworking under the lockdown period, as well as medical causes including COVID-19 infection per se, may have caused major emotional distress, especially in the most vulnerable patients. We aimed to evaluate the variations in the number of admissions due to Takotsubo syndrome (TTS) during the COVID-19 pandemic in the Veneto region. Methods: We retrospectively reviewed and analyzed the number of admissions because of TTS in 13 Divisions of Cardiology located in the Veneto region, the northeastern area of Italy, covering a population of more than 2.5 million inhabitants, during the two major pandemic waves of COVID-19 (the first between 15 March and 30 April 2020 and the second between 15 November and 30 December 2020) that occurred in 2020. Results: In total, 807 acute coronary syndromes were admitted in the 13 enrolling hospitals. Among these, 3.9% had TTS. Compared to the corresponding 2018 and 2019 time periods, we observed a significant increase in the number of TTS cases (+15.6%, p = 0.03 and +12.5%, p = 0.04, comparing 2018 to 2020 and 2019 to 2020, respectively). Geographical distribution of the TTS cases reflected the broad spread of the SARS-CoV-2 infection with a significant direct relationship between TTS incidence and the number of COVID-19 infections according to Pearson's correlation (r = 0.798, p < 0.001). Conclusions: The higher incidence of TTS during the 2020 COVID-19 pandemic waves, especially in the areas that were hit hardest in terms of morbidity and mortality by the SARS-CoV-2 infection, suggest a strong direct and/or indirect role of COVID-19 in the pathogenesis of TTS.


Subject(s)
COVID-19 , Takotsubo Cardiomyopathy , COVID-19/epidemiology , Communicable Disease Control , Humans , Italy/epidemiology , Pandemics , Retrospective Studies , SARS-CoV-2 , Takotsubo Cardiomyopathy/epidemiology
3.
J Cardiovasc Dev Dis ; 8(10)2021 Sep 23.
Article in English | MEDLINE | ID: mdl-34677186

ABSTRACT

Fontan-associated liver disease (FALD) is an arising clinical entity that can occur long after a successful Fontan operation for correction of single ventricle (SV) congenital heart disease (CHD). Occurrence of FALD is characterized by liver cirrhosis and other hepatic complications, and determinates an increased morbidity and mortality. Currently, there is no consensus on how to stage FALD. We report here our experience by an observational study in 52 patients with SV-CHD after Fontan operation that were recruited through a period of 36 ± 9.3 months. All cases underwent lab tests and liver and cardiac imaging evaluation, including liver stiffness (LS) measurement by transient elastography (TE) (FibroScan®). According to selective criteria for liver disease, we identified 23/43 (53.5%) cases with advanced FALD that showed: older age (p < 0.05), larger hepatic and cava veins diameter (p < 0.05), worsened NYHA class (p < 0.05), abnormal lymphocytes (p < 0.01), platelet count (p < 0.05), and GGT, prothrombin time (INR), albumin and cystatin C levels (p < 0.05), with respect to cases without advanced FALD. LS values were significantly increased in cases with advanced FALD, at cut-off values higher than 22 kPa (p < 0.001). LS, and its combined score with spleen diameter and platelet count (LSPS) successfully helped to detect 100% of cases with portal hypertension (p < 0.001). In conclusion, LS can be effective to stage FALD and to uncover cases with severe risk of complications, avoiding higher morbidity and mortality related to advanced FALD.

4.
J Cardiovasc Echogr ; 31(2): 68-72, 2021.
Article in English | MEDLINE | ID: mdl-34485031

ABSTRACT

BACKGROUND: The great technological advancements in the field of echocardiography have led to applications of stress echocardiography (SE) in almost all diagnostic fields of cardiology, from ischemic heart disease to valvular heart disease and diastolic function. However, the assessment of the right ventricle (RV) in general, and in particular in regard to the contractile reserve of the RV, is an area that has not been previously explored. We, therefore, propose a study to investigate the potential use of SE for the assessment of RV function in adult patients. AIMS AND OBJECTIVES: The primary aim is to evaluate the feasibility of right ventricular SE. The secondary aim is to assess right ventricular contractile reserve. MATHERIALS AND METHODS: Eighty-one patients undergoing a physical or dobutamine stress echocardiogram for cardiovascular risk stratification or chest pain were the subject of the study. An exercise leg cycle using a standard WHO protocol was used to simultaneously assess the right and left ventricular global and regional function as well as acquiring Doppler data. Whereas the patient had limitations in mobility, a dobutamine SE was be performed. We evaluated the average values of tricuspid annular plane systolic excursion (TAPSE), fractional area change (FAC), S-wave, systolic pulmonary artery pressure (sPAP), and right ventricle global longitudinal (free wall) strain (RVGLS) during baseline and at the peak of the effort. RV contractile reserve was defined as the change in RVGLS from rest to peak exercise. We also assessed the reproducibility of these measurements between two different expert operators (blind analysis). RESULTS: At least 3 over 5 RV function parameters were measurable both during baseline and at the peak of the effort in 95% of patients, while all 5 parameters in 65% of our population, demonstrating an excellent feasibility. All RV-studied variables showed a statistically significant increase (P < 0.001) at peak compared to the baseline. The average percentage increases at peak were 31.1% for TAPSE, 24.8% for FAC, 50.6% for S-wave, 55.2% for PAPS, and 39.8% for RV strain. The reproducibility between operators at baseline and peak was excellent. Our study demonstrates that TAPSE, FAC, and S-wave are highly feasible at rest and at peak, while TAPSE, S-wave, and sPAP are the most reliable measurements during RV stress echo. CONCLUSION: RVGLS is useful in the assessment of RV contractile reserve in patients with good acoustic window. Further studies are needed to evaluate the impact of contrast echocardiography in improving RV contractile reserve assessment during SE.

5.
Braz Oral Res ; 32: e42, 2018 May 24.
Article in English | MEDLINE | ID: mdl-29846390

ABSTRACT

Based on aroeira's (Myracrodruon urundeuva) antimicrobial activity and a future trend to compose intracanal medication, the aim of this study was to assess in vivo inflamatory tissue response to the extracts by edemogenic and histological analysis containing inactivated facultative and anaerobic microorganisms. For edema quantification, eighteen animals were divided into three groups (n = 3, periods: 3 and 6 hours) and 0.2 mL of 1% Evans blue per 100 g of body weight was injected into the penile vein under general anesthesia. After 30 min the animals received a subcutaneous injection in the dorsal region of aqueous or ethanolic extract of aroeira or saline (control) containing inactivated bacteria. Samples were collected, immersed in formamide for 72h, and evaluated by spectrophotometry (630 m). For histological analysis, polyethylene tubes with the extracts were implanted in the dorsal of 30 male rats. Analysis of the fibrous capsule and inflammatory infiltrate were performed after 7 and 30 days. The aqueous extract group induced less edema in both postoperative periods compared to the other groups, but the differences were not significant (p > 0.05). Tissue repair was significantly better after 30 days than after 7 days (p < 0.01). The aqueous solution showed less inflammatory response than the ethanolic solution (p < 0.05), with tendency for better results than control after 7 days. After 30 days, the response to both extracts was similar to control. The aqueous and ethanolic aroeira extracts containing inactivated microorganisms showed a trend for better results than saline, even when associated with microorganisms, and facilitated the tissue repair process.


Subject(s)
Anacardiaceae/chemistry , Edema/prevention & control , Gram-Negative Bacteria/drug effects , Gram-Positive Bacteria/drug effects , Inflammation/prevention & control , Plant Extracts/pharmacology , Subcutaneous Tissue/microbiology , Animals , Edema/pathology , Gram-Negative Bacteria/classification , Gram-Positive Bacteria/classification , Inflammation/pathology , Male , Rats , Rats, Wistar , Subcutaneous Tissue/drug effects , Subcutaneous Tissue/pathology , Time Factors
6.
Braz. oral res. (Online) ; 32: e42, 2018. tab, graf
Article in English | LILACS | ID: biblio-889494

ABSTRACT

Abstract: Based on aroeira's (Myracrodruon urundeuva) antimicrobial activity and a future trend to compose intracanal medication, the aim of this study was to assess in vivo inflamatory tissue response to the extracts by edemogenic and histological analysis containing inactivated facultative and anaerobic microorganisms. For edema quantification, eighteen animals were divided into three groups (n = 3, periods: 3 and 6 hours) and 0.2 mL of 1% Evans blue per 100 g of body weight was injected into the penile vein under general anesthesia. After 30 min the animals received a subcutaneous injection in the dorsal region of aqueous or ethanolic extract of aroeira or saline (control) containing inactivated bacteria. Samples were collected, immersed in formamide for 72h, and evaluated by spectrophotometry (630 m). For histological analysis, polyethylene tubes with the extracts were implanted in the dorsal of 30 male rats. Analysis of the fibrous capsule and inflammatory infiltrate were performed after 7 and 30 days. The aqueous extract group induced less edema in both postoperative periods compared to the other groups, but the differences were not significant (p > 0.05). Tissue repair was significantly better after 30 days than after 7 days (p < 0.01). The aqueous solution showed less inflammatory response than the ethanolic solution (p < 0.05), with tendency for better results than control after 7 days. After 30 days, the response to both extracts was similar to control. The aqueous and ethanolic aroeira extracts containing inactivated microorganisms showed a trend for better results than saline, even when associated with microorganisms, and facilitated the tissue repair process.


Subject(s)
Animals , Male , Rats , Anacardiaceae/chemistry , Edema/prevention & control , Gram-Negative Bacteria/drug effects , Gram-Positive Bacteria/drug effects , Inflammation/prevention & control , Plant Extracts/pharmacology , Subcutaneous Tissue/microbiology , Edema/pathology , Gram-Negative Bacteria/classification , Gram-Positive Bacteria/classification , Inflammation/pathology , Rats, Wistar , Subcutaneous Tissue/drug effects , Subcutaneous Tissue/pathology , Time Factors
7.
J Card Surg ; 29(5): 678-85, 2014 Sep.
Article in English | MEDLINE | ID: mdl-25040614

ABSTRACT

BACKGROUND: Total anomalous pulmonary venous connection (TAPVC) is a rare congenital heart disease (CHD), whose surgical repair is associated with high mortality and reoperation rates. We sought to identify predictors of early and late outcomes. METHODS: Data from medical records of patients who underwent surgical repair for TAPVC from 1989 to 2012 were included. The patients were divided in two groups, according to absence or presence of associated major CHDs. RESULTS: Forty-six patients were included (M/F: 26/20, median age 26 days, interquartile range 15 to 59, median weight 3.350 kg, interquartile range 1800 to 4470). Anatomic types of TAPVC were: supracardiac in 48%, intracardiac in 20%, infracardiac in 20%, and mixed in 12%; TAPVC was obstructive in 33%; TAPVC was isolated in 63%, complex in 37%. Single ventricle physiology was present in 11 patients, heterotaxy in eight patients. Overall operative mortality was 19.6% (9/46): 6.9% in isolated TAPVC, 41.2% in complex type (p-value: 0.002). It was associated with low weight at intervention (<3 kg, p = 0.027), single ventricle physiology (p = 0.047), and aortic cross-clamp time >60 minutes (p = 0.097). At a median follow-up of 2.97 years (range 43 days to 22 years, 91% complete), there were nine late deaths (24.3%); 15 patients (40.5%) had major events (including late death). Multivariate analysis of event-free survival showed worse outcome in the complex group (p = 0.001). CONCLUSION: Surgical mortality and morbidity remain consistent in patients with TAPVC and associated major CHD, while the isolated type shows excellent outcomes. Pulmonary vein obstruction is a rare but highly lethal complication. doi: 10.1111/jocs.12399 (J Card Surg 2014;29:678-685).


Subject(s)
Scimitar Syndrome/surgery , Abnormalities, Multiple , Body Weight , Heart Defects, Congenital/complications , Humans , Infant , Infant, Newborn , Male , Postoperative Complications/prevention & control , Prognosis , Pulmonary Veno-Occlusive Disease/prevention & control , Retrospective Studies , Scimitar Syndrome/complications , Scimitar Syndrome/mortality , Time Factors , Treatment Outcome , Vascular Surgical Procedures/methods , Vascular Surgical Procedures/mortality
8.
J Coll Physicians Surg Pak ; 22(11): 716-9, 2012 Nov.
Article in English | MEDLINE | ID: mdl-23146853

ABSTRACT

Patients with congenital malformations, traumatic or pathological mutilation and maxillofacial developmental disorders can be restored aesthetically and emotionally by the production and use of facial prostheses. The aim of this study was to review the literature about the retention and processing methods of facial prostheses, and discuss their characteristics. A literature review on Medline (PubMed) database was performed by using the keywords "maxillofacial prosthesis, silicone, esin, pigment, cosmetic, prosthetic nose", based on articles published from 1956 to 2010. Several methods of retention, from adhesives to the placement of implants, and different processing methods such as laser, CAD/CAM and rapid prototyping technologies have been reported. There are advantages and disadvantages of each procedure, and none can be classified as better compared to others.


Subject(s)
Craniofacial Abnormalities/surgery , Maxillofacial Prosthesis , Nose/surgery , Prosthesis Design , Prosthesis Failure , Prosthesis Implantation/methods , Adhesives , Computer-Aided Design , Humans , Nasal Surgical Procedures/statistics & numerical data , Prosthesis Implantation/statistics & numerical data , Plastic Surgery Procedures/methods , Resins, Synthetic
9.
Gerodontology ; 29(2): e215-9, 2012 Jun.
Article in English | MEDLINE | ID: mdl-21083743

ABSTRACT

OBJECTIVE: The effect of artificial ageing on the hardness, absorption, solubility, and colour of soft denture liners was investigated. MATERIALS AND METHODS: Liner materials based on acrylic resin (Trusoft) or silicone (Dentusil, Ufi Gel P, and Ufi Gel SC) were tested before and after 2000 thermal cycles. A total of 20 specimens of each material were tested. Half of the specimens were used for hardness and colour evaluation, and the remainder for absorption and solubility tests. The hardness evaluation was carried out using a Shore A durometer, while absorption and solubility tests were performed by storing samples in a desiccator and weighing daily until reaching constant mass (W1). After thermocycling, the samples were again weighed (W2) and dried (W3). Colour was measured using a spectrophotometer. Statistical analysis was performed using GraphPad InStat at the p < 0.05 level. RESULTS: Thermocycling significantly affected the hardness of the specimens. The Trusoft material exhibited the highest absorption (1.48 ± 0.48), solubility (1.26 ± 0.28), and colour change (3.92 ± 0.33), significantly different from the other materials. There were no significant differences among the silicones in terms of absorption, solubility, and colour change, except for the colour of Dentusil, which changed (0.83 ± 0.11). CONCLUSION: It can be concluded that silicone liners performed significantly better compared to acrylic resin.


Subject(s)
Dental Materials/chemistry , Denture Liners , Absorption , Acrylic Resins/chemistry , Color , Desiccation , Dimethylpolysiloxanes/chemistry , Hardness , Humans , Materials Testing , Methylmethacrylates/chemistry , Polymethyl Methacrylate/chemistry , Silicone Elastomers/chemistry , Solubility , Spectrophotometry/instrumentation , Surface Properties , Temperature , Time Factors
10.
Int J Prosthodont ; 24(2): 155-7, 2011.
Article in English | MEDLINE | ID: mdl-21479284

ABSTRACT

The aim of this study was to evaluate the effects of carbamide peroxide (CP) on surfaces of different restorative materials. Porcelain, composite resin, glass ionomer, and amalgam were analyzed in this study. Surface roughness (Ra) was measured before and after treatment with 10% and 15% CP. Fifteen percent CP increased Ra values in both the glass ionomer and amalgam subgroups, while 10% CP increased Ra values in the glass ionomer subgroup only. Changes in restorative material surfaces can be more severe when bleaching is completed without a clinician's supervision. Hence, thorough patient examinations must be done before, during, and after bleaching treatment.


Subject(s)
Dental Materials/chemistry , Peroxides/chemistry , Tooth Bleaching Agents/chemistry , Urea/analogs & derivatives , Carbamide Peroxide , Composite Resins/chemistry , Dental Amalgam/chemistry , Dental Polishing/methods , Dental Porcelain/chemistry , Glass Ionomer Cements/chemistry , Humans , Humidity , Materials Testing , Resin Cements/chemistry , Resins, Synthetic/chemistry , Surface Properties , Temperature , Time Factors , Urea/chemistry
11.
J Craniofac Surg ; 21(4): 1270-3, 2010 Jul.
Article in English | MEDLINE | ID: mdl-20613613

ABSTRACT

Both the cleaning and care of the prosthesis are fundamental for maintaining its quality. Therefore, the aim of this study was to show the methods of cleaning and care the patient needs to take as regards the prosthesis and adjacent tissue, starting with correct instruction and training by the professional. It has been verified that among the materials for fabricating maxillofacial prostheses, silicone was considered the major retainer of microorganisms on its surface. Therefore, for cleaning prostheses, the use of water and neutral soap, as well as chlorhexidine, is recommended. As regards care of the adjacent tissues, it is recommended to remove the prosthesis before going to sleep, in addition to washing the prosthesis receptor tissues with water and neutral soap or with a mixture of hydrogen peroxide and water. Whereas for the mucosal surfaces of the ophthalmic cavity, cleaning with filtered and boiled water or physiological solution at least 3 times a day is recommended.


Subject(s)
Decontamination/methods , Maxillofacial Prosthesis , Chlorhexidine , Humans , Hydrogen Peroxide , Silicones , Soaps , Water
12.
J Coll Physicians Surg Pak ; 19(10): 670-1, 2009 Oct.
Article in English | MEDLINE | ID: mdl-19811725

ABSTRACT

Hand deformities affect aesthetics function of hand severely compromised and also cause psychological disturbances. This report describes the fabrication of a silicone finger prosthesis for a patient after an accident at work. The finger prosthesis was retained by a vacuum effect on the stump. The silicone material Silastic-MDX 44210 was used to provide function and aesthetics. The finger prosthesis offered psychological, functional and rehabilitative advantages for the patient. Restoring the natural appearance with the prosthesis eliminated the trauma generated by the dysfunction and represented an efficient psychological therapy.


Subject(s)
Artificial Limbs , Finger Injuries/rehabilitation , Fingers/surgery , Accidents, Occupational , Amputation, Traumatic/psychology , Amputation, Traumatic/rehabilitation , Finger Injuries/psychology , Humans , Silicone Elastomers
13.
Braz Oral Res ; 23(2): 144-8, 2009.
Article in English | MEDLINE | ID: mdl-19684948

ABSTRACT

One of the greatest challenges faced by buccomaxillofacial prosthetists is to reproduce the patient's exact skin color and provide adequate esthetics. To reach this objective, professionals must use materials with easy characterization and that maintain color over long periods of time. The objective of this study was, thus, to evaluate the color stability of two types of silicones, Silastic 732 and Silastic MDX4-4210. Twenty-four test specimens were made from each type of silicone and were divided into a colorless group and groups intrinsically pigmented with ceramics, cosmetics or iron oxide. The specimens were submitted to an accelerated system of aging for non-metallic materials. Readings were carried out initially and after periods corresponding to 163, 351, 692 and 1,000 hours of aging, using a reflection spectrophotometer analysis, and color alterations were calculated by the CIE L*a*b* system. The data were submitted to variance analysis and Tukey's test at a 5% level of probability. The results demonstrated that, irrespective of the period of time analyzed, all the materials underwent some type of chromatic alteration (DeltaE > 0). The test specimens made with Silastic 732 and MDX4-4210, without pigmentation, presented the lowest color alteration values after 1,000 hours of aging. Of the pigments, ceramic presented the lowest color alteration values and cosmetic powder presented the highest values. Thus, it may be concluded that the materials without the incorporation of pigments presented similar color alteration values, and did not differ statistically. The cosmetic powder used in this study was the pigment that most altered the color of the test specimens.


Subject(s)
Maxillofacial Prosthesis , Prosthesis Coloring , Silicone Elastomers/chemistry , Analysis of Variance , Color , Coloring Agents , Materials Testing , Pigmentation , Silicone Elastomers/radiation effects , Spectrophotometry , Temperature , Time Factors
14.
Prim Dent Care ; 16(3): 127-30, 2009 Jul.
Article in English | MEDLINE | ID: mdl-19566987

ABSTRACT

INTRODUCTION: Soft liners have been developed to offer comfort to denture wearers. However, this comfort is compromised when there is a change in the properties of the material, causing colour change, solubility, absorption and hardening. These characteristics can compromise the longevity of soft liners. AIM: The aim of this in vitro study was to investigate the effect of ageing on both the hardness and colour change of two soft liners following accelerated ageing. METHODS: Two denture liners, one resin based (Trusoft, Bosworth, Illinois, USA) and one silicone based (Ufi Gel P, Voco GMBH, Cuxhaven, Germany), were tested in this study for both hardness (using the Shore A scale) and colour change (using the CIE L*a*b* colour scale), initially and after 1008 hours (6 weeks) of accelerated ageing. Statistical analysis was performed using the unpaired t-test with the Welch correction. RESULTS: These indicated that both materials increased in hardness and underwent colour change after accelerated ageing. The initial hardness of Trusoft was far lower than that of Ufi Gel P (18.2 Shore A units vs 34.8 Shore A units). However, for Trusoft the changes for both hardness (from 18.2 to 52.1 Shore A units) and colour change (16.85 on the CIE L*a*b* colour scale) were greater than those for Ufi Gel P, for which hardness changed from 34.8 to 36.5 Shore A units and the colour change was 5.19 on the CIE L*a*b* colour scale. CONCLUSIONS: Ufi Gel P underwent less hardness and colour change after accelerated ageing than Trusoft. On the other hand, the use of Trusoft may be preferable in cases where initial softness is a major consideration, such as when relining an immediate denture after implant surgery.


Subject(s)
Dental Materials/chemistry , Denture Liners , Absorption , Color , Dimethylpolysiloxanes/chemistry , Elasticity , Hardness , Humans , Materials Testing , Polymethyl Methacrylate/chemistry , Saliva, Artificial/chemistry , Silicone Elastomers/chemistry , Solubility , Spectrophotometry, Ultraviolet , Surface Properties , Temperature , Time Factors , Viscosity
15.
Indian J Dent Res ; 20(1): 77-80, 2009.
Article in English | MEDLINE | ID: mdl-19336865

ABSTRACT

OBJECTIVES: The objective of this study was to evaluate by a visual method of comparison the color stability of nonpigmented and pigmented facial silicones after accelerated aging. MATERIALS AND METHODS: Two kinds of silicones were used in this study; one specifically formulated for facial prostheses and the other an acetic silicone for industrial use. Twenty-four trial bodies were made for each silicone. These were divided into colorless and intrinsically pigmented groups: ceramic, make-up, and iron oxide. The groups were submitted to accelerated aging for nonmetallic materials. An initial reading and subsequent readings were made at 163, 351, 692, and 1000 hours using a visual method of comparison. The values were annotated in a spreadsheet by two observers, according to scores elaborated for this study. RESULTS: All groups presented color stability in the visual method. According to the results obtained and analyzed in this study, we can conclude that both silicones, Silastic 732 RTV and Silastic MDX 4-4210, behaved similarly, they can therefore be indicated for use in maxillofacial prosthesis. The time factor of aging influenced negatively, independently of the pigmentation, or lack of it, and of silicones and no group had visually noticeable alterations in any of the accelerated aging time, independently of the addition or not of pigments.


Subject(s)
Maxillofacial Prosthesis , Prosthesis Coloring , Silicones/chemistry , Color , Color Perception , Coloring Agents , Dimethylpolysiloxanes/chemistry , Materials Testing , Prosthesis Design , Silicone Elastomers/chemistry , Time Factors
16.
J Prosthodont ; 18(1): 32-5, 2009 Jan.
Article in English | MEDLINE | ID: mdl-19166546

ABSTRACT

PURPOSE: The longevity of an ocular prosthesis is directly related to the resistance to erosion of its material. The purpose of this study was to evaluate the effects of chemical disinfection and the method of investment on the microhardness of ocular prosthesis acrylic resin. MATERIALS AND METHODS: Thirty-two test specimen investments were obtained in two silicones. A segment was cut in each test specimen, and each specimen was fixed in an acrylic disk. The specimens were then polished and submitted to the first microhardness test before immersion in distilled water and incubation for 2 months. During this 2-month period, the specimens were immersed in a water bath at 37 degrees C and were disinfected daily; half were disinfected with neutral soap and the other half were disinfected with 4% chlorhexidine gluconate. After the storage phase and disinfection, a second microhardness test was performed. The surface microhardness values for the acrylic resins were submitted to ANOVA, followed by the Tukey test. RESULTS: The disinfection and the period of storage did not statistically influence the surface microhardness of the acrylic resin, independent of the method of investment of the specimens (Zetalabor or Vipi Sil). The investment of specimens with Zetalabor silicone presented a greater surface hardness, independent of the type of disinfection and the period of storage. CONCLUSIONS: Based on these results, we suggest that the microhardness of the resin evaluated was not influenced by the method of disinfection or the time of storage used and was affected only by the investment material.


Subject(s)
Acrylic Resins/chemistry , Disinfection/methods , Eye, Artificial , Silicones/chemistry , Chlorhexidine/analogs & derivatives , Disinfectants , Hardness , Humans , Materials Testing , Microwaves , Random Allocation , Soaps , Surface Properties , Waxes
17.
Cardiovasc Intervent Radiol ; 32(3): 563-7, 2009 May.
Article in English | MEDLINE | ID: mdl-18791763

ABSTRACT

We report the case of a very large anomalous connection of the veins draining the upper lobe of the left lung to both the left-sided vertical vein and the left atrium, associated with mild rheumatic mitral valve stenosis, in which the atrial septum was intact and the remaining venous system, including the coronary sinus, was otherwise normal (a variant of Lutembacher's syndrome). In order to abolish the left-to-right shunting, a transcatheter approach to close this venous structure was successfully attempted using an Amplatzer ASD Occluder device. The technical aspects and the alternative options of performing a procedure with a device for a purpose outside the scope of its approved label are discussed.


Subject(s)
Coronary Vessel Anomalies/therapy , Lutembacher Syndrome/therapy , Pulmonary Veins/abnormalities , Aged , Cardiac Catheterization , Comorbidity , Coronary Angiography , Coronary Vessel Anomalies/diagnosis , Echocardiography , Electrocardiography , Female , Humans , Lutembacher Syndrome/diagnosis
18.
Braz. oral res ; 23(2): 144-148, 2009. tab
Article in English | LILACS | ID: lil-522294

ABSTRACT

One of the greatest challenges faced by buccomaxillofacial prosthetists is to reproduce the patient's exact skin color and provide adequate esthetics. To reach this objective, professionals must use materials with easy characterization and that maintain color over long periods of time. The objective of this study was, thus, to evaluate the color stability of two types of silicones, Silastic 732 and Silastic MDX4-4210. Twenty-four test specimens were made from each type of silicone and were divided into a colorless group and groups intrinsically pigmented with ceramics, cosmetics or iron oxide. The specimens were submitted to an accelerated system of aging for non-metallic materials. Readings were carried out initially and after periods corresponding to 163, 351, 692 and 1,000 hours of aging, using a reflection spectrophotometer analysis, and color alterations were calculated by the CIE L*a*b* system. The data were submitted to variance analysis and Tukey's test at a 5 percent level of probability. The results demonstrated that, irrespective of the period of time analyzed, all the materials underwent some type of chromatic alteration (ÄE > 0). The test specimens made with Silastic 732 and MDX4-4210, without pigmentation, presented the lowest color alteration values after 1,000 hours of aging. Of the pigments, ceramic presented the lowest color alteration values and cosmetic powder presented the highest values. Thus, it may be concluded that the materials without the incorporation of pigments presented similar color alteration values, and did not differ statistically. The cosmetic powder used in this study was the pigment that most altered the color of the test specimens.


Subject(s)
Maxillofacial Prosthesis , Prosthesis Coloring , Silicone Elastomers/chemistry , Analysis of Variance , Color , Coloring Agents , Materials Testing , Pigmentation , Spectrophotometry , Silicone Elastomers/radiation effects , Temperature , Time Factors
20.
ImplantNews ; 5(4): 379-383, jul.-ago. 2008. ilus
Article in Portuguese | LILACS, BBO - Dentistry | ID: lil-518144

ABSTRACT

Diversos fatores podem afetar a biomecânica do complexo sistema prótese-implante e tecido ósseo circunjacente das próteses implanto-suportadas com extensão distal. Desta forma, o presente trabalho discute alguns aspectos relacionados com a biomecânica de próteses sobreimplantes com cantiléver, como: o comprimento da extensão distal, comprimento do implante, design da barra metálica e dentição antagonista.


Subject(s)
Biomechanical Phenomena , Bite Force , Dental Implants , Prostheses and Implants
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