Understanding family caregivers' needs to support relatives with advanced progressive disease at home: an ethnographic study in rural Portugal.

BACKGROUND: Family caregivers play an important role supporting their relatives with advanced progressive disease to live at home. There is limited research to understand family caregiver needs over time, particularly outside of high-income settings. The aim of this study was to explore family caregivers' experiences of caring for a relative living with advanced progressive disease at home, and their perceptions of met and unmet care needs over time. METHODS: An ethnographic study comprising observations and interviews. A purposive sample of 10 family caregivers and 10 relatives was recruited within a rural area in the north of Portugal. Data were collected between 2014 and 16 using serial participant observations (n = 33) and in-depth interviews (n = 11). Thematic content analysis was used to analyse the data. RESULTS: Five overarching themes were yielded: (1) provision of care towards independence and prevention of complications; (2) perceived and (3) unknown caregiver needs; (4) caregivers' physical and emotional impairments; and (5) balancing limited time. An imbalance towards any one of these aspects may lead to reduced capability and performance of the family caregiver, with increased risk of complications for their relative. However, with balance, family caregivers embraced their role over time. CONCLUSIONS: These findings enhance understanding around the needs of family caregivers, which are optimally met when professionals and family caregivers work together with a collaborative approach over time. Patients and their families should be seen as equal partners. Family-focused care would enhance nursing practice in this context and this research can inform nursing training and educational programs.

Healthcare professionals and volunteers education in palliative care to promote the best practice-an integrative review.

BACKGROUND: Family caregivers' empowerment can assume strategic importance in palliative care. Healthcare professionals and volunteers have been showing significant gaps in this field. Hence, education has been advocated as an effective strategy to fill this gap. While several educational initiatives exist, a comprehensive evidence synthesis on the effectiveness of educational training on healthcare professionals and volunteers is lacking. AIMS: An integrative review was conducted to explore worldwide initiatives, aiming to improve healthcare professionals and volunteers' competence in a palliative care setting especially in relation to the family caregiver. METHOD: A scoping literature review was conducted with systematic searches in multiple databases - REDALYC, CINAHL, SCIELO, EBSCO, ERIC and MEDLINE since January 2012. Studies were selected based on programmes content and its impact evaluation. Four researchers assessed the studies regarding their eligibility with reference to the inclusion and exclusion criteria. FINDINGS: Twenty-two studies met the eligibility criteria. Multi-professional learning was reported, emphasising nurses and physician's enrolment. Only few studies showed participants' learning outcomes. Inconsistencies in delivery mode and duration were identified. Impact evaluations were heterogeneous and relied on no validated instruments. Family caregiver's content was addressed only in three initiatives. CONCLUSIONS: Further research is needed using a more reliable design, mode of delivery and impact measurement of educational training. In addition, more initiatives associated with cost-effectiveness, shorter- and longer-term clinical impact are needed. Despite the strides already made towards the establishment of an evidence base for healthcare professionals in the field of palliative care, either greater consideration is required for family care providers in the education of healthcare professionals and respect for the cultural diversity.

The relationship between frailty, functional dependence, and healthcare needs among community-dwelling people with moderate to severe dementia.

This paper examines the healthcare needs of community-dwelling older people living in Porto, Portugal, diagnosed with moderate or severe dementia, linked to functional dependency, cognitive decline, limitations in the activities of daily life, and frailty levels. A sample of 83 participants was recruited. Data were collected between 2013 and 2017. A sociodemographic questionnaire, the Clinical Dementia Rating (CDR), the Barthel Index (BI), the Lawton and Brody Instrumental Activities of Daily Living (IADL) Scale, and the Edmonton Frail Scale (EFS) were used. A set of 26 healthcare needs was defined to support the assessment. The Pearson chi-square or Fisher's exact test (as appropriate) was used to examine the association of the needs (unmet and met) with the levels of dementia and frailty. Participants were diagnosed previously with moderate or severe dementia and benefited from a structured home-care program. There was a high number rated as "severe dementia," "fully dependent," "severely or fully dependent in the activities of daily living (ADL)," and "severe frailty." There were statistically significant differences among needs identified in people with moderate or severe dementia and moderate or severe frailty. The most prevalent healthcare needs in the sample were food preparation, medication/taking pills, looking after their home, toilet use, sensory problems, communication/interaction, bladder, bowels, eating and drinking, memory, sleeping, and falls prevention. In particular, the study identifies a set of needs that are present simultaneously in both frailty and dementia stages. This study underlines that despite well-structured home-care programs for people with dementia, unmet health needs remain. Timely healthcare needs assessment may help professionals to avoid fragmented care and to tailor quality-integrated interventions, including the emotional and psychological balance of the caregiver.

Perception of caregivers of persons with schizophrenia about a health education program

The mental health policy of Brazil has been guided by the search for citizenship, social equality and autonomy of the individuals with mental disorders and it star-ted with the deinstitutionalization process. On the other hand, this paradigm shift contributed to making the patients stay in the family environment and thus the need for family members to play the role of caregivers. The attributions of these care functions have contributed to a physical and emotional overload. Using a psychoeducational approach focused on the family member/caregiver of people with schizophrenia, this study proposed to check the caregivers' perception about the importance of the practice of relaxation activities for the promotion of self-care. The intervention was performed during a six-month period. Participants were 31 family caregivers of mental health cohabitation centers in the city of Belo Hori-zonte, Brazil. Using the relatives' reports about the perception of the intervention, categories were listed and treated with the support of the software webQDA. The results revealed through the family members' perception, that the intervention program provided them with contributions such as wellbeing, self-control over impulses, increased self-esteem, and encouragement for self-care. The literature reinforces that the educational practice in health is composed of educational ac-tivities aimed at the development of individual and collective capacities aimed at improving the health and quality of life of people. The intervention program with relaxation exercises contributed to an improved physical and mental health for fa-mily caregivers, awakening them to self-care

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Response of non-motor symptoms to levodopa in late-stage Parkinson's disease: Results of a levodopa challenge test.

BACKGROUND: Non-motor symptoms (NMS) are extremely common among late-stage Parkinson's disease (LSPD) patients. Levodopa (L-dopa) responsiveness seems to decrease with disease progression but its effect on NMS in LSPD still needs to be investigated. OBJECTIVE: To assess the response of blood pressure (BP), pain, fatigue and anxiety to L-dopa in LSPD patients. METHODS: 20 LSPD patients, defined as Schwab and England ADL Scale <50 or Hoehn Yahr Stage >3 (MED ON) and 22 PD patients treated with subthalamic deep brain stimulation (advanced PD group) underwent an L-dopa challenge. BP and orthostatic hypotension (OH) assessment, a visual analogue scale (VAS) for pain and fatigue and the Strait Trait Anxiety (STAI) were evaluated before and after the L-dopa challenge. RESULTS: Systolic BP dropped significantly after L-dopa intake (p < 0.05) in LSPD patients, while there was no change in pain, fatigue or anxiety. L-dopa significantly improved (p < 0.05) pain and anxiety in the advanced PD group, whereas it had no effect on BP or fatigue. L-dopa-related adverse effects (AEs), namely OH and sleepiness, were more common among LSPD patients. 40% and 65% of LSPD patients were not able to fill out the VAS and the STAI, respectively, while measurement of orthostatic BP was not possible in four LSPD patients. CONCLUSIONS: This exploratory study concludes that some non-motor variables in LSPD do not benefit from the acute action of L-dopa while it can still induce disabling AEs. There is a need for assessment tools of NMS adapted to these disabled LSPD patients.

Do patients with late-stage Parkinson's disease still respond to levodopa?

BACKGROUND: Late-stage Parkinson' disease (PD) is dominated by loss of autonomy due to motor and non-motor symptoms which can be marginally corrected by medications adjustments. However, controversy exists on the mechanisms underlying the apparent decrease of benefit from levodopa. OBJECTIVE: To study the response to levodopa in late-stage PD (LSPD). METHODS: 20 LSPD patients (Schwab and England ADL Scale <50 or Hoehn Yahr Stage >3 in MED ON) and 22 PD patients treated with subthalamic deep brain stimulation (DBS) underwent an acute levodopa challenge test. MDS-UPDRS-III and the modified Abnormal Involuntary Movement Scale were evaluated in off and after administration of a supra-maximal levodopa dose. RESULTS: LSPD patients had a median age of 78.8 (IQR: 73.5-82) and median disease duration of 14 years (IQR: 10-19.75). DBS patients had a median age of 66 (IQR: 61-72) and median disease duration of 18 years (IQR: 15-22). LSPD and DBS patients' MDS-UPDRS-III score improved 11.3% and 37% after levodopa, respectively. Rest tremor showed the largest improvement, while axial signs did not improve in LSPD. However, the magnitude of levodopa response significantly correlated with dyskinesias severity in LSPD patients. One third of LSPD and 9% of DBS patients reported moderate drowsiness. CONCLUSIONS: LSPD patients show a slight response to a supra-maximal levodopa dose, which is greater if dyskinesia are present, but it is frequently associated with adverse effects. A decrease in levodopa response is a potential marker of disease progression in LSPD.

Evaluation of the quality of different endodontic obturation techniques by digital radiography.

OBJECTIVES: This study was aimed to evaluate different endodontic obturation techniques (Thermafil, lateral condensation, and Tagger's hybrid technique) regarding the homogeneity of the obturation radiopacity. MATERIALS AND METHODS: Seventy roots of human upper central incisors were filled using the Thermafil system, lateral condensation. and Tagger's hybrid technique. Radiopacity of the filling was evaluated based on mean of grey levels, and its homogeneity was assessed by the coefficient of variation (CV), analyzing the histograms obtained of digitized and digital radiographs. RESULTS: The increase in mean grey levels (p < 0.001) and reduction in the CV (p < 0.05) were higher for Tagger's hybrid technique compared with other methods. CONCLUSIONS: Tagger's hybrid technique provided better homogeneity of the obturation radiopacity and better apical sealing compared with lateral condensation technique. CLINICAL RELEVANCE: The results suggest that Tagger's hybrid technique provided the best compaction of the root canal filling material, an important factor for the sealing of obturations and, consequently, for the effectiveness of treatment.

Accuracy of linear measurements before and after digitizing periapical and panoramic radiography images.

The aim of this study was to evaluate the accuracy of linear measurements made on conventional and digitized periapical and panoramic radiographic images of dry human hemi-mandibles. Images from the posterior region of 22 dry human hemi-mandibles were obtained by conventional panoramic and periapical radiography technique. Using a digital caliper, 3 vertical measurements were marked directly on the dry hemi-mandibles (reference measurements) as well as on the tracing from the conventional radiographic images of the specimens made onto acetate paper sheet: Distance 1: between the upper limit of the alveolar ridge and the lower limit at the mandible base; Distance 2: between the upper limit of the alveolar ridge and the upper limit of the mandibular canal; Distance 3: between the lower limit of the mandibular canal and the lower limit of the mandible base. Next, the radiographs were digitized and the three measurements were made on the digital images using UTHSCSA Image Tool software. Data were analyzed statistically by one-way ANOVA (α=0.05). There was no statistically significant differences (p>0.05) between periapical and panoramic radiographs or between the measurements recorded using the digital caliper and UTHSCSA software compared with dry mandible specimens for Distances 1 (p=0.783), 2 (p=0.986) and 3 (p=0.129). In conclusion, the radiographic techniques evaluated in this study are reliable for vertical bone measurements on selected areas and the UTHSCA Image Tool software is an appropriate measurement method.

Accuracy of linear measurements before and after digitizing periapical and panoramic radiography images

The aim of this study was to evaluate the accuracy of linear measurements made on conventional and digitized periapical and panoramic radiographic images of dry human hemi-mandibles. Images from the posterior region of 22 dry human hemi-mandibles were obtained by conventional panoramic and periapical radiography technique. Using a digital caliper, 3 vertical measurements were marked directly on the dry hemi-mandibles (reference measurements) as well as on the tracing from the conventional radiographic images of the specimens made onto acetate paper sheet: Distance 1: between the upper limit of the alveolar ridge and the lower limit at the mandible base; Distance 2: between the upper limit of the alveolar ridge and the upper limit of the mandibular canal; Distance 3: between the lower limit of the mandibular canal and the lower limit of the mandible base. Next, the radiographs were digitized and the three measurements were made on the digital images using UTHSCSA Image Tool software. Data were analyzed statistically by one-way ANOVA (α=0.05). There was no statistically significant differences (p>0.05) between periapical and panoramic radiographs or between the measurements recorded using the digital caliper and UTHSCSA software compared with dry mandible specimens for Distances 1 (p=0.783), 2 (p=0.986) and 3 (p=0.129). In conclusion, the radiographic techniques evaluated in this study are reliable for vertical bone measurements on selected areas and the UTHSCA Image Tool software is an appropriate measurement method.

O objetivo deste estudo foi avaliar a acurácia de medidas lineares realizadas em radiografias panorâmicas e periapicais convencionais e digitalizadas de hemimandíbulas humanas secas. Imagens da região posterior de 22 hemimandíbulas humanas secas foram obtidas pelas técnicas panorâmica e periapical convencionais. Com o paquímetro eletrônico digital, foram realizadas três medições verticais diretamente sobre as hemimandíbulas (medidas referenciais), bem como sobre o decalque das imagens convencionais, em papel de acetato: Distância 1: Distância entre o limite superior do rebordo alveolar e o limite inferior da base da mandíbula; Distância 2: Distância entre o limite superior do rebordo alveolar e o limite superior do canal mandibular e Distância 3: Distância entre o limite inferior do canal mandibular e o limite inferior da base da mandíbula. Posteriormente, as radiografias foram digitalizadas e as três medidas foram realizadas nas imagens digitais utilizando o programa UTHSCSA Image Tool. Os dados foram analisados estatisticamente pelo teste ANOVA a um critério (α=0,05). Não houve diferenças estatisticamente significantes (p>0,05) entre as radiografias panorâmicas e periapicais, assim como para as medidas obtidas com o paquímetro e pelo programa UTHSCSA Image Tool, quando comparados aos espécimes mandibulares, avaliando as distâncias 1 (p=0,783), 2 (p=0,986) e 3 (p=0,129). Em conclusão, as técnicas radiográficas avaliadas neste estudo mostraram-se confiáveis para mensurações ósseas verticais na área selecionada e o programa de digitalização de imagens UTHSCSA Image Tool é um método adequado de aferição.

Effects of radio-opacifier addition in dental impression material.

OBJECTIVE: The aim of this in vitro study was to determine the effects of barium sulfate addition in two dental impression materials previously proved as radiolucent. MATERIALS AND METHODS: An irreversible hydrocolloid (IH) and polyether (PE) were tested for optical density, linear dimension stability and detail reproduction. STATISTICAL ANALYSIS USED: The optical density data were submitted to Kolmogorov-Smirnov normality test and compared with two-way ANOVA and Tukey (alpha=0.05). RESULTS: The results of optical density (pixel) were: IH control 45.24 f (+/-7.6), PE control 54.93 e (+/-4.45), PE 5Wt% 60.43 d (+/-6.27), IH 1Wt% 61.54 cd (+/-5.3), PE 1Wt% 66.9 bc (+/-5.05), IH 5Wt% 67.17 b (+/-6.01), PE 10Wt% 84.55 a (+/-5.14), IH 10Wt% 85.33 a (+/-5.53). On detail reproduction, polyether control was able to copy the 6 microm line. Adding 1 or 5Wt% of barium sulfate have not change this characteristic. For the irreversible hydrocolloid, the control group was able to copy a line with 14 microm, however, adding 1Wt% barium sulfate, the capability decreased to 22 microm. Adding barium sulfate in the polyether promoted an increase in between the copied lines, for the control, the average distance was 931.6 microm, 936 microm to 1Wt% and 954.5 microm to 5 Wt%. For the IH, the control presented 975 microm in comparison to 987.25 microm for 1 Wt% samples. CONCLUSION: The addition of barium sulfate was capable of increasing significantly the optical density of tested material, have changed the linear dimension stability, however, have not interfered in detail reproduction only for PE.

Accuracy of periapical radiography, panoramic radiography and computed tomography for examining the mental foramen region / Acurácia de radiografia periapical, radiografia panorâmica e tomografia computadorizada para exame da região do forame mentual

Purpose: To determine the accuracy of different radiographic methods for bone height estimation at the mental foramen area. Methods: Twenty dry human hemimandibles were examed by using periapical and panoramic radiography, and computed tomography. An electronic digital caliper was used to measure the tracings obtained from the radiographies in three different times (groups A1, A2 and A3) and inthe cross-sectioned hemimandibles (group B). Measurements consisted of: Measure 1 - from the upper limit of the alveolar ridge to the upper limit of the mental foramen; Measure 2 - from the upper limit of the mental foramen to the inferior limit of the cortical bone of the base of the jaw; Measure 3 - from the upper limit of the alveolar ridge to the inferior limit of the cortical bone of the base of the jaw. Data were analyzed with Student-t and Friedman tests. Results: The average difference values in Measure 1 were 0.33 mm, 0.35 mm and 0.85 mm for the periapical radiography, computed tomography and panoramic radiography, respectively (confidence intervals of 0.17 mm to 0.49 mm, 0.18 mm to 0.53 mm and 0.38 mm to 1.32 mm, respectively). Panoramic radiographies showed the greatest differences in Measures 2 and 3, with average values of 1.05 mm and 1.93 mm, respectively. Conclusion: Periapical radiography and computed tomography showed the best accuracy. Asafety margin for surgical purposes has been suggested.

Objetivo: Determinar a acurácia de diferentes métodos radiográficos para estimação de altura óssea na região do forame mentual. Metodologia: Vinte hemi-mandíbulas humanas, secas, foram examinadas por radiografia periapical e panorâmica e tomografia computadorizada. Um paquímetro digital foi usado para medir os traçados obtidos das radiografias em três diferentes tempos (grupos A1, A2 e A3) e nas hemi-mandíbulas seccionadas transversalmente (grupo B). As medições foram: Medida 1 - do limite superior da crista óssea ao limite superior do forame mentual; Medida 2 - do limite superior do forame mentual ao limite inferior do osso cortical da base da mandíbula; Medida 3 - do limite superior da crista óssea ao limite inferior do osso cortical da base da mandíbula. Os dados foram analisados por teste t de Student e teste de Friedman. Resultados: Os valores médios de diferença na Medida 1 foram 0,33 mm, 0,35 mm e 0,85 mm para a radiografia periapical, tomografia computadorizada e radiografia panorâmica, respectivamente (intervalos de confiança de 0,17 a 0,49 mm, 0,18 a 0,53 mm e 0,38 a 1,32 mm, respectivamente). As radiografias panorâmicas mostraram as maiores diferenças nas Medidas 2 e 3, com valores médios de 1,05 mm e 1,93 mm, respectivamente. Conclusão: A radiografia periapical e a tomografia computadorizada mostraram a melhor acurácia. Sugere-se uma margem de segurança em caso de cirurgias.

Range of exposure time and image quality in conventional and digital radiographs: an in vitro study

The purpose of this study was to determine the range of exposure time to obtain acceptable bitewing radiographic images using conventional (InSight, Kodak) and digital (DenOptixTM, Gendex) systems. Thirty sound molars were radiographed by bitewing technique at exposure times ranging from 0.06s to 2.50s. Five dental radiologists evaluated the resulting 340 radiographs, classifying them as(1) unacceptable, (2) acceptable and (3) of good quality. Frequencies were analyzed by Kruskal-Wallis and Wilcoxon tests, and inter-examiner agreement was determined by Cohen’s kappa statistics. Radiographs of good diagnostic quality in conventional system were obtained with exposure times ranging from 0.10s to 1.00s while in digital system the time ranged from 0.06s to 1.60s (P<0.05). It was also observed that 75.3 per cent of the digital images and 47.1 per cent of the conventional images were considered of good quality...

O objetivo deste estudo foi determinar o intervalo de tempo de exposição aceitável para obter imagens radiográficas interproximais utilizando sistemas convencionais (Insight, Kodak) e digital (DenOptixTM, Gendex). Trinta molares foram radiografados pela técnica interproximal em tempos de exposição variando de 0.06s de 2.50s. Cinco radiologistas odontólogos avaliaram 340 radiografias classificando-as como (1) inaceitáveis, (2) aceitável e (3) de boa qualidade. As freqüências foram analisadas pelo teste de Kruskal-Wallis e Wilcoxon, e concordância entre os examinadores foi determinada pela estatística kappa de Cohen. As radiografias de boa qualidade diagnóstica em sistema convencional foram obtidos com tempos de exposição variando de 0,10s a 1.00s, enquanto no sistema digital, o tempo variou de 0.06s a 1.60s para (P <0,05). Também foi observado que 75,3 por cento das imagens digitais e 47,1 por cento das imagens convencionais foram considerados de boa qualidade...

Optical density and chemical composition of microfilled and microhybrid composite resins.

This study evaluated the optical density of two microfilled and two microhybrid resins, as well as the composition of these materials with regard to their optical density. Cavities prepared in 12 2-mm- or 4-mm-thick acrylic plastic plates were filled with Z250 (3M-ESPE), A110 (3M-ESPE), Charisma (Heraeus-Kulzer) and DurafillVS (Heraeus-Kulzer). The resin increments (2-mm-thick) were light-cured for 40 s. Three 0.12-s radiographic exposures were made of each #2 acrylic plastic plate. DenOptix system optical plates were used to obtain the digital images. Three readings of the composite resin surface were made in each radiograph, totalizing 216 readings. The mean of highest and lowest grey-scale values was obtained. Two specimens of each composite resin were prepared for SEM analysis of the chemical elements related to optical density, using energy dispersive x-ray analysis (EDX). The results were subjected to Shapiro-Wilk's test, ANOVA, Tukey's test at 1% level of significance and Pearson's correlation. The mean grey-scale values at 2 mm and 4 mm were: Z250 = 154.27a and 185.33w; A110 = 46.77b and 63.05y; Charisma = 163.40c and 200.46z; DurafillVS = 43.92b and 58.99x, respectively. Pearson's test did not show any positive correlation between optical density and percentage weight of optical density chemical elements. It was concluded that the microhybrid resins had higher optical density means than the microfilled resins; among the evaluated resins, Charisma had the highest optical density means.

Preload and torque removal evaluation of three different abutment screws for single standing implant restorations.

Several authors still consider the mechanical problems of fracture and component loosening as the main causes of failure of implant-supported restorations. The purpose of this in vitro study was to compare the preload of three types of screw for transmucosal abutment attachment used in single implant-supported prosthesis through strain gauge and removal torque measurements. Three external hex fixtures were used, and each received a transmucosal abutment (Cera One), which was fixed to the implant with its respective screw: Group A- gold screw, Group B- titanium screw and Group C- surface-treated titanium screw (Ti-Tite). Ten screws of each type were attached applying a 30.07+/-0.28 Ncm torque force and maintained in position for 5 minutes. After this, the preload values were measured using strain gauges and a measurement cell. Gold screws presented higher preload values (131.72+/-8.98 N), followed by surface-treated titanium screws (97.78+/-4.68 N) and titanium screws (37.03+/-5.69 N). ANOVA (p<0.05) and Tukey's test (p<0.05) were applied. Statistically significant differences were found among the groups for both preload and removal torque values. In conclusion, gold screws may be indicated to achieve superior longevity of the abutment-implant connection and, consequently, prosthetic restoration due to greater preload values yielded.

Radiopacity of impression materials using an indirect digital system / Radiopacidade de materiais de moldagem usando um sistema digital indireto

Purpose: This in vitro study evaluated the radiopacity of impression materials using an indirect digital system. Methods: Samples of four polyvinyl siloxanes, one polyether, one polysulfide, and one irreversible hydrocolloid were fabricated with 1.0, 1.5, and 3.5mm-thickness. Three samples of different thickness were placed on the Digora optical plate and exposed. The optical density (pixels) was recorded in three areas resulting in a total of 360 measurements. Data were analyzed by 2-way ANOVA and Tukey tests (α=0.05). Results: Significant differences were observed among all materials and thicknesses tested (P<0.001). Irreversible hydrocolloid and polyether showed the lowest optical density. Polysulfide showed the highest optical density under all evaluated conditions. Conclusion: There was a significant difference in optical density for all impression materials tested. Composition changes are suggested to allow radiographic detection and improve safety during clinical use of impression materials.

Objetivo: Este estudo in vitro comparou a radiopacidade de materiais de moldagem usando um método radiográfico digital indireto. Metodologia: Amostras de quatro polivinil-siloxanos, um poliéter, um polissulfeto e um hidrocolóide irreversível foram confeccionadas com alturas de 1, 1,5 e 3,5mm. Três amostras das diferentes espessuras foram dispostas sobre uma placa óptica Digora e exposta. A densidade óptica (pixels) foi registrada em três diferentes áreas de cada amostra. Os dados foram analisados pelo teste de análise de variância de dois fatores e teste de Tukey (α=0,05). Resultados: Diferenças significantes foram observadas entre todos os materiais e espessuras testadas (P<0,001). O hidrocolóide irreversível e o poliéter apresentaram a menor densidade óptica. O polissulfeto apresentou a maior densidade óptica em todas as condições avaliadas. Conclusão: Há diferença significativa na densidade óptica dos materiais de moldagem avaliados. Alterações na composição são necessárias para facilitar a detecção destes materiais a fim de aumentar a segurança no uso clínico.

A comparison between panoramic digital and digitized images to detect simulated periapical lesions using radiographic subtraction.

This study compared digital and digitized panoramic radiographs to detect incipient periapical lesions using the digital subtraction radiography (DSR) technique. Bone defects were created in 77 apical sites of dried human mandibles through the application of 70% perchloric acid. Conventional and digital radiographs were obtained twice at time zero and 2, 4, and 6 hours after application of the acid solution. Conventional radiographs were digitized by using the same attributes than direct digital radiographs. The baseline images were subtracted of the negative control and experimental groups and assessed by an experienced and blinded observer who assigned score 0 (normal) or 1 (mineral loss) to each image. The sensitivity of both modalities was statistically different in relation to experimental times. The percentage of correct responses significantly increased regarding experimental times. The specificity was high both for digitized and digital images. DSR of panoramic images, both digitized and digital, allows for the diagnosis of incipient-simulated periapical lesions with no differences in their performance.

Optical density and chemical composition of microfilled and microhybrid composite resins

This study evaluated the optical density of two microfilled and two microhybrid resins, as well as the composition of these materials with regard to their optical density. Cavities prepared in 12 2-mm- or 4-mm-thick acrylic plastic plates were filled with Z250 (3M-ESPE), A110 (3M-ESPE), Charisma (Heraeus-Kulzer) and DurafillVS (Heraeus-Kulzer). The resin increments (2-mm-thick) were light-cured for 40 s. Three 0.12-s radiographic exposures were made of each #2 acrylic plastic plate. DenOptix system optical plates were used to obtain the digital images. Three readings of the composite resin surface were made in each radiograph, totalizing 216 readings. The mean of highest and lowest grey-scale values was obtained. Two specimens of each composite resin were prepared for SEM analysis of the chemical elements related to optical density, using energy dispersive x-ray analysis (EDX). The results were subjected to Shapiro-Wilk's test, ANOVA, Tukey's test at 1 percent level of significance and Pearson's correlation. The mean grey-scale values at 2 mm and 4 mm were: Z250 = 154.27a and 185.33w; A110 = 46.77b and 63.05y; Charisma = 163.40c and 200.46z; DurafillVS = 43.92b and 58.99x, respectively. Pearson's test did not show any positive correlation between optical density and percentage weight of optical density chemical elements. It was concluded that the microhybrid resins had higher optical density means than the microfilled resins; among the evaluated resins, Charisma had the highest optical density means.

Preload and torque removal evaluation of three different abutment screws for single standing implant restorations

Several authors still consider the mechanical problems of fracture and component loosening as the main causes of failure of implant-supported restorations. The purpose of this in vitro study was to compare the preload of three types of screw for transmucosal abutment attachment used in single implant-supported prosthesis through strain gauge and removal torque measurements. Three external hex fixtures were used, and each received a transmucosal abutment (Cera One®), which was fixed to the implant with its respective screw: Group A- gold screw, Group B- titanium screw and Group C- surface-treated titanium screw (Ti-Tite®). Ten screws of each type were attached applying a 30.07±0.28 Ncm torque force and maintained in position for 5 minutes. After this, the preload values were measured using strain gauges and a measurement cell. Gold screws presented higher preload values (131.72±8.98 N), followed by surface-treated titanium screws (97.78±4.68 N) and titanium screws (37.03±5.69 N). ANOVA (p<0.05) and Tukey's test (p<0.05) were applied. Statistically significant differences were found among the groups for both preload and removal torque values. In conclusion, gold screws may be indicated to achieve superior longevity of the abutment-implant connection and, consequently, prosthetic restoration due to greater preload values yielded.

Detection of proximal caries in conventional and digital radiographs: an in vitro study.

OBJECTIVES: To compare digital images to conventional film radiography in the diagnosis of proximal caries. METHODS: Fifty-one molars and 24 premolars were studied and divided in groups of three teeth. They were fixed in silicone and radiographed using InSight film (Kodak) and the digital systems Digora (Soredex), DenOptix (Gendex) and CygnusRay MPS (Progeny). Twenty-five radiographs were obtained in each modality and four proximal surfaces were analyzed in each radiograph. Radiographs were interpreted individually by one observer at three different sessions for each imaging modality. Caries lesions were classified according to their depth: (0) absent; (1) restricted to enamel; (2) reaching the dentino-enamel junction; and (3) reaching the dentin. The teeth were sectioned and ground in order to obtain the gold standard and were examined histologically by stereomicroscopy. RESULTS: The Kendall test was employed and showed a good intra-observer agreement among the three evaluations implemented. The sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) were all calculated, and there were no significant differences observed among the four imaging modalities studied (ANOVA, p< or =0.05). Besides, the ROC curve was determined for each modality and no statistically significant differences were observed when comparing the areas under the ROC curve at the 5% level of significance. CONCLUSIONS: The results demonstrate that the diagnostic accuracy of digital images is similar to that of conventional film radiography in the detection of proximal caries.