Effect of elastomeric urethane monomer on physicochemical properties and shrinkage stress of resin composites

Abstract This study aimed to evaluate the effect of an elastomeric urethane monomer (Exothane-24) in different concentrations on physicochemical properties, gap formation, and polymerization shrinkage stress of experimental resin composites. All experimental composites were prepared with 50 wt.% of Bis-GMA and 50 wt.% of TEGDMA, to which 0 wt.% (control), 10 wt.%, 20 wt.%, 30 wt.%, and 40 wt.% of Exothane-24 were added. Filler particles (65 wt.%) were then added to these resin matrixes. Ultimate tensile strength (UTS: n = 10), flexural strength (FS: n = 10), flexural modulus (FM: n = 10), hardness (H: n = 10), hardness reduction (HR: n = 10), degree of conversion (DC: n = 5), gap width (GW: n = 10), and polymerization shrinkage stress in Class I (SS-I: n = 10) and Class II (SS-II: n = 10) simulated configuration. All test data were analyzed using one-way ANOVA and Tukey's test (α = 0.05; β= 0.2). Exothane-24 in all concentrations decreased the H, HR, DC, GW, SS-I, and SS-II (p < 0.05) without affecting the UTS, and FS (p > 0.05). Reduction in FM was observed only in the Exothane 40% and 30% groups compared to the control (p < 0.05). Exothane-24 at concentrations 20% and 30% seems suitable since it reduced GW and polymerization SS without affecting the properties of the composite resins tested, except for H.

Resumo Este estudo teve como objetivo avaliar o efeito de um monômero elastomérico de uretano (Exothane-24) em diferentes concentrações em propriedades físico-químicas, formação de fenda e tensão de contração de polimerização de resinas compostas experimentais. Todos os compósitos experimentais foram preparados com 50% em peso de Bis-GMA e 50% em peso de TEGDMA, nos quais 0% (controle), 10%, 20%, 30% e 40% em peso de Exothane-24 foram adicionados. Partículas de carga (65% em peso) foram então adicionadas as matrizes resinosas. Resistência coesiva (RC: n = 10), resistência à flexão (RF: n = 10), módulo de flexão (MF: n = 10), dureza (D: n = 10), redução de dureza (RD: n = 10), grau de conversão (GC: n = 5), largura de fenda (LF: n = 10) e tensão de contração de polimerização em simulações de cavidades Classe I (TC-I: n = 10) e Classe II (TC-II: n = 10). Todos os dados do teste foram analisados usando one-way ANOVA e teste de Tukey (α = 0,05; β = 0,2). O Exothane-24 em todas as concentrações diminuiu a D, RD, GC, LF, TC-I e TC-II (p < 0,05) sem afetar o RC e RF (p > 0,05). A redução da MF foi observada apenas nos grupos Exothane 40% e 30% em relação ao controle (p < 0,05). O Exothane-24 nas concentrações de 20% e 30% pareceu ser adequado, pois reduziu LF e TC de polimerização sem afetar as propriedades das resinas compostas testadas, exceto para D.

Effects of Different Storage Temperatures on the Properties of Nonlatex Orthodontic Modules

Objective: To evaluate and compare the effect of variation in storage temperatures and duration on a tensile load at failure of elastomeric modules. Methods: In total, 140 modules were used in the study, 20 of which were tested on day 0 as received from a company using a Universal testing machine for baseline estimation of tensile load at failure. The rest 120 modules were divided into 6 groups. Groups I, II, and III modules were stored at low (T1 = 1–5°C), moderate (T2 = 20–25°C) and high (T3 = 35–40°C) temperatures, respectively, for 6 months. Groups IV, V and VI modules were stored at temperatures T1, T2 and T3 for 1 year, respectively, and were tested for tensile load at failure. Results: The tensile load at failure for the control group was 21.588 ± 1.082 N and for 6?month interval at temperatures T1, T2 and T3 was 18.818 N ± 1.121 N, 17.841 N ± 1.334 N and 17.149 N ± 1.074 N, respectively, and for 1 year, it was 17.205 N ± 1.043 N, 16.836 N ± 0.487 N and 14.788 N ± 0.781 N, respectively. The tensile load at failure decreased significantly from 6 months to 1 year among each temperature group. Conclusions: Maximum force degradation was seen in modules at high temperature followed by medium temperature and low temperature at both 6 months and 1 year intervals, and tensile load at failure decreased significantly from 6 months to 1 year storage duration. These results conclude that the temperature and duration at which the samples were exposed during storage produce a significant change in the forces exerted by the modules.

Refractory cancer pain in young child at end?of?life: Can we alleviate the suffering?

Pain is a common and highly distressing symptom in children with advanced malignancies and it is often multifactorial at the end?of?life. The prognosis of cancer pain is reported to be worse in those with mixed pain type, high pain severity, daily opioid use, and poor emotional well?being. We describe a case of 13?year?old boy, known case of metastatic Ewing sarcoma right iliac bone, who presented to our palliative care ward with intractable pain and was finally discharged home for terminal care with high doses of morphine, ketamine, and midazolam infusion through elastomeric pump attached to a peripherally inserted central catheter (PICC line). The suffering of imminently dying children should be reduced, and judicious dose escalation of opioids along with adjuvants is appropriate and often necessary.

Force decay and discoloration of thermoplastic and thermoset orthodontic elastomeric chains / Diminuição de força e descoloração de elásticos corrente termoplásticos e termofixos

Objective: Elastomeric chains are commonly used to apply force for orthodontic dental movements. However, force decay and discoloration are two important weak points of these materials. The present study intended to compare the force decay and color stability of different types of elastomeric chains. Material and Methods: This in vitro study evaluated 6 groups of elastomeric chains, including thermoplastic (TP) and thermoset (TS) chains made by the companies American Orthodontics (AO), Ormco (OR), and G&H Orthodontics (GH). The elastomeric chain forces were measured at the baseline, following 1 hour, 1 day, 1, 2, 3, 4, 5, and 6 weeks of stretching. The elongation required for the chains to exert a force of 250 g was calculated. ΔE of each group was calculated by a spectrophotometer following immersion in black tea solution for 6 days. Data were analyzed using the SPSS 22 software and the statistical methods of repeated measures analysis of variance and two-way analysis of variance (P<0.05). Results: The force decay of the TS chains were significantly lower than the TP chains in the 6-week study duration (P<0.05), and the lowest and highest force decay was observed in the products by AO and GH, respectively. The highest force degradation occurred during the first week in all groups. The elongation rate needed for the TS chains was significantly higher than the TP chains (P<0.05), and the highest elongation rate was observed in the products by OR. TS chains showed significantly higher color stability than TP chains, and products by OR and GH had better color stability than the products by AO. Conclusion: The present study showed that TS chains were superior to TP chains in force decay and color stability in all the brands studied. (AU)

Objetivo: Elásticos corrente são comumente utilizados para aplicar forças para a movimentação ortodôntica. Porém, a diminuição de força e descoloração são duas importantes fraquezas desses materiais. O presente estudo tem o objetivo de comparar a diminuição de força e estabilidade de cor de diferentes tipos de elásticos corrente. Material e Métodos: Este estudo in vitro avaliou 6 grupos de elásticos corrente, incluindo termoplástico (TP) e termofixo (TS) produzidos pelas empresas American Orthodontics (AO), Ormco (OR) e G&H Orthodontics (GH). A força dos elásticos corrente foram mensuradas no início, após 1 hora, 1 dia, 1, 2, 3, 4, 5 e 6 semanas de alongamento. A força de alongamento necessária para aplicação de 250g foi calculada. O ΔE de cada grupo foi calculado por um espectrofotômetro após a imersão em solução de chá preto por 6 dias. Os dados foram analizados utilizando o programa SPSS 22 e a análise estatística foi realizada por análise de variância e análise de variância dois fatores (p<0,05). Resultados: A diminuição da força do grupo TS foi significativamente menor que o grupo TP em 6 semanas de estudo (p<0,05), e o menor e maior valor de diminuição de força foi observado nos produtos da empresa AO e GH, respectivamente. A maior degradação de força ocorreu durante a primeira semana em todos os grupos. A taxa de alongamento necessária para o grupo TS foi significativamente maior que o grupo TP (p<0,05), e a maior taxa de alongamento foi observada nos produtos da empresa OR. Os elásticos TS obtiveram resultados significativamente maiores de estabilidade de cor que os elásticos TP, e os produtos da OR e GH tiveram melhor estabilidade de cor que oa produtos AO. Conclusão: O presente estudo demonstrou que os elásticos TS foram superiores aos elásticos TP em diminuição de força e estabilidade de cor em todas as marcas estudadas.(AU)

Generation I and Generation II Elastomeric Chains Characteristics Comparison in Artificial Saliva Immersion / Comparação das Características dos Elásticos Ortodônticos tipo Corrente de Geração I e Geração II em Imersão em Saliva Artificial

Objective: To determine the force decay and discoloration in Generation I and Generation II elastomeric chain on artificial saliva immersion. Material and methods: Generation I and Generation II elastomeric chains stretched on an acrylic board and immersed in artificial saliva for 1, 7, 14, 21, and 28 days according to the group of days. On each specified day, the force of each sample measured by an orthodontic force gauge and the magnitude of the force obtained is entered to the formula to find out the force decay in percentage, whereas discoloration of each sample analyzed by the color reader with CIE Lab analysis. Results: The force decay between Generation I and Generation II elastomeric chains showed a statistically significant difference in every group of days, in which Generation II is more effective in maintaining stretch force. Similar to force decay, the discoloration in Generation I elastomeric chains on the 14th day showed significant value and Generation II elastomeric chains were more stable in maintaining color compared to Generation I. Conclusions: over the entire research period time, Generation II elastomeric chains are more stable in maintaining stretch forces and color compared to Generation I elastomeric chains. (AU)

Objetivo: Determinar a queda de força e descoloração nos elásticos ortodônticos tipo corrente de Geração I e Geração II na imersão em saliva artificial. Material e métodos: Elásticos Geração I e Geração II foram esticados em placas de acrílico e imersas em saliva artificial por 1, 7, 14, 21 e 28 dias, de acordo com o grupo de dias. Em cada dia especificado, a força de cada amostra medida por um medidor de força ortodôntica e a magnitude da força obtida são inseridos na fórmula para descobrir sua queda em porcentagem, enquanto a descoloração de cada amostra foi analisada pelo leitor de cores "CIE Lab". Resultados: A queda da força entre os elásticos Geração I e Geração II apresentou diferença estatisticamente significativa em todos os grupos de dias, sendo que a de Geração II foi mais efetiva na manutenção da força de alongamento. Semelhante à queda de força, a descoloração nos elásticos da Geração I mostrou um valor significativo no 14º dia, e elásticos da Geração II foram mais estáveis na manutenção da cor em comparação com a Geração I. Conclusões: durante todo o período de pesquisa, os elásticos tipo corrente da Geração II foram mais estáveis na manutenção das forças de alongamento e da cor em comparação com os elásticos da Geração I (AU)

Reemplazo de hombro ambulatorio: Presentación de protocolo perioperatorio y resultados iniciales / Same-day discharge shoulder arthroplasty: Perioperative protocol and initial results

Introducción El reemplazo de hombro es efectivo para mejorar el dolor y la funcionalidad en patologías crónicas del hombro. Considerando los riesgos y costos asociados a la estancia hospitalaria, realizar este procedimiento de forma ambulatoria surge como una opción para optimizar esta estrategia terapéutica. Materiales & Métodos Estudio observacional descriptivo prospective de pacientes operados por un mismo cirujano con artroplastia de hombro ambulatoria (RHA) utilizando analgesia regional con bomba de infusión elastomérica. Se registraron las escalas de ASES y SANE, el dolor, la satisfacción del paciente, las complicaciones y reingresos a 90 días. Resultados Se intervinieron 10 pacientes de un promedio de edad de 59.6 (±3.9) años, siendo el 40% prótesis anatómicas, 50% reversas y 10% hemiartroplastia. Al cuarto día postoperatorio el dolor por EVA fue 1,3 (±0,62) y al décimo día 2,7 (±1,1). La puntuación SANE antes del procedimiento fue de 31 (±9,7), y 90 días después fue de 76,1 (±6,8). Todos los pacientes refirieron una alta satisfacción. Un paciente al 3er día presentó un episodio de broncoespasmo leve, tratado de forma ambulatoria. Un paciente presentó una infección superficial que mejoró completamente con el antibiótico oral. No se presentaron reingresos o consultas a urgencias a 90 días. Discusión Se presentan los desenlaces a corto plazo de la primera serie de casos en nuestro medio de RH ambulatorio. Este procedimiento puede ser realizado de forma segura, siguiendo un protocolo estandarizado y realizando una juiciosa selección de los pacientes.

Background Shoulder arthoplasty is an effective procedure to improve pain and function in chronic shoulder pathologies. Considering the risks and costs associated with hospital stay, performing joint replacements on an outpatient setting emerges as an option to optimize this therapeutic strategy. Methods A prospective analysis was performed in 10 patients undergoing same-day discharge total shoulder arthroplasty with anatomic and reverse prostheses. Pain was managed with a continuous peripheral interscalene block using an elastomeric infusion pump. ASES and SANE scores, pain, patient satisfaction, complications, and readmissions after 90 days were recorded. Results 10 patients (average age 59.6 (±3.9) years) underwent outpatient shoulder arthroplasty (50% reverse shoulder arthroplasty, 40% total shoulder arthroplasty and 10% hemiarthroplasty). On post-operative day 4, mean visual analogue scale (VAS) for pain assessment was 1.3 (±0.62) and day 10, 2.7 (±1.1). Pre-operative SANE score was 31 (±9.7), and 90 days after the procedure was 76.1 (±6.8). All patients were satisfied with the procedure. One patient had a mild bronchospasm on day 3 that resolved with bronchodilators on an outpatient basis. One patient had a superficial surgical site infection that resolved completely with oral antibiotics administration. There were no re-admissions or major complications.

The influence of elastomeric ligatures pigmentation on smile aesthetics during orthodontic treatment

ABSTRACT Aim: To assess the influence of elastomeric ligatures, subjected to a previous in vitro pigmentation process using different substances, on smile aesthetics during orthodontic treatment, from the perception of students and professionals. Methods: Eight elastomeric ligatures of five commercial brands (3M/Unitek, American Orthodontics, Morelli, Ortho Technology, and Orthometric) (n=8) were immersed in coffee, Coca-Cola, and red wine for one minute per day, for 28 days; and another group of ligatures was immersed in artificial saliva. All samples were photographed and subsequently analyzed using the Adobe Photoshop software, by the RGB method. Afterwards, the pigmented ligatures were inserted in a patient wearing orthodontic brackets, and zoomed photographs of the smile were taken and presented to 40 evaluators, who filled in a satisfaction scale sheet to express their opinion on the smile aesthetics of each photograph. The color data were subjected to analysis of variance (ANOVA) and Tukey tests. Results: The substance with the highest pigmentation potential was coffee (p< 0.05) followed by red wine (p< 0.05). Comparison among the brands used in this study showed that American Orthodontics and Orthometric had the lowest degree of pigmentation when immersed in coffee and red wine (p< 0.05), respectively. However, the brand that showed the highest level of satisfaction among the evaluators was Ortho Technology. Conclusions: The presence of pigmented elastomeric ligatures affected smile aesthetics, when compared with the control group.

RESUMO Objetivo: Avaliar a influência das ligaduras elásticas submetidas a um processo prévio de pigmentação in vitro, com diferentes substâncias, na estética do sorriso durante o tratamento ortodôntico, segundo a percepção de alunos e profissionais. Métodos: Oito ligaduras elásticas de cinco marcas comerciais (3M Unitek, American Orthodontics, Morelli, Ortho Technology e Orthometric) (n = 8) foram imersas em café, Coca-Cola e vinho tinto por um minuto por dia, por 28 dias, e outro grupo de ligaduras foi imerso em saliva artificial. Todas as amostras foram fotografadas e posteriormente analisadas no software Adobe Photoshop, pelo método RGB. Em seguida, as ligaduras pigmentadas foram inseridas em um paciente com braquetes ortodônticos, e fotografias ampliadas do sorriso foram tiradas e apresentadas a 40 avaliadores, que preencheram uma escala de satisfação para representar sua opinião sobre a estética do sorriso de cada fotografia. Os dados de cor foram submetidos à análise de variância (ANOVA) e testes de Tukey. Resultados: A substância com maior potencial de pigmentação foi o café (p< 0,05), seguido do vinho tinto (p< 0,05). A comparação entre as marcas utilizadas nesse estudo mostrou que a American Orthodontics e a Orthometric apresentaram o menor grau de pigmentação quando imersas em café e vinho tinto (p< 0,05), respectivamente. Porém, a marca que apresentou maior nível de satisfação entre os avaliadores foi a Ortho Technology. Conclusões: A presença de ligaduras elásticas pigmentadas afetou a estética do sorriso, quando comparada à do grupo controle.

Bomba elastomérica, aplicación de citostáticos en hospital de día oncológico / Elastomeric pump, application of cytostatics

Introducción. Este espacio es acerca del empleo de bombas elastoméricas en la administración de citostáticos de infusión continua con pacientes oncológicos que reciben tratamiento endovenoso, de infusión continua en el domicilio, mejorando así la calidad de vida del paciente, (esta experiencia es sólo en relación a aplicación de 5 fluorouracilo).Material y método: Al inicio, la primera dosis de quimioterapia, se realiza en el internado común para observar la tolerancia a la medicación, y en la segunda o tercera aplicación se realiza la misma en el hospital de día la primera parte del esquema, y luego se realiza la conexión de la bomba elastomérica que infundirá durante 46hs con el 5 fluorouracilo. El paciente asistirá al hospital oncológico para realizar la desconexión. Nuestro rol enfermero de contención y capacitación es necesario y así poder asegurar el buen manejo del dispositivo y brindar seguridad a los pacientes, para que logren un cuidado autónomo, seguro y eficaz. Para tal fin se les provee un instructivo. Poseer catéter implantable es requisito obligatorio para esta modalidad. Beneficios encontrados: es portátil y ergonómico, Mejora la movilidad y autocuidado, tasa de infusión exacta. Características de seguridad, que incluyan la protección del reservorio frente a posibles daños; Descomprimimos las internaciones, reducimos la espera de camas para internación de pacientes. Reducimos el uso de bombas comunes eléctricas del internado quedando a disponibilidad para otros pacientes hospitalizados. Dificultades halladas: Desconocimiento del paciente sobre el insumo (bomba). Inseguridad del paciente al encontrarse en el hogar por primera vez. Trámites burocráticos para autorización de la bomba. Conclusión: esta implementación innovadora requiere aún más aprendizaje, contamos con el apoyo del Departamento de Enfermería y la jefatura del servicio del Hospital de Día Oncológico, para el uso de las bombas. Para esta experiencia se utilizaron 10 bombas elastoméricas. Experiencia práctica, positiva para el paciente, además él mismo se compromete con su autocuidado y tratamiento, se logra evitar las exposiciones nosocomiales minimizando así los riesgos de contagios. Reducimos el uso de bombas comunes eléctricas del internado quedando a disposición para otros pacientes que lo requieran. Descomprimimos el internado común permitiendo así contar con más camas y mayor fluidez para satisfacer la demanda de internación de pacientes con otras patologías[AU]

Introduction. This space is about the use of elastomeric pumps in the administration of cytostatics of continuous infusion with cancer patients who receive intravenous treatment, of continuous infusion of qmt at home, thus improving the quality of life of the patient, (this experience is only in relation to to application of 5 fluorouracil). Material and method: At the beginning, the first dose of chemotherapy is carried out in the common boarding school to observe the tolerance to the medication, and in the second or third application it is carried out in the day hospital the first part of the scheme, and then the elastomeric pump is connected, which will infuse for 46 hours with 5 fluorouracil. The patient will attend the cancer hospital at hour 46 to perform the disconnection. Our nursing role of containment and training is necessary in order to ensure the proper handling of the device and provide safety to patients, so that they achieve autonomous, safe and effective care. For this purpose, an instruction manual is provided. Having an implantable catheter is a mandatory requirement for this modality; Benefits found: It is portable and ergonomic, Improves mobility and self-care, exact infusion rate. Safety features, including protection of the reservoir against possible damage; We decompressed hospitalizations, we reduced the wait for beds for patient admission. We reduced the use of common electric pumps in the internship, making them available for other hospitalized patients. Difficulties encountered: Lack of knowledge of the patient about the input (pump). Patient insecurity when being at home for the first time. Bureaucratic procedures for authorization of the pump. Conclusion. This innovative implementation requires even more learning, we have the support of the Nursing Department and the head of the Oncology Day Hospital service, for the use of the pumps. For this experiment 10 elastomeric pumps were used. Practical experience, positive for the patient, he also commits himself to self-care and treatment, it is possible to avoid nosocomial exposures, thus minimizing the risks of contagion. We reduce the use of common electric pumps in the internship by being available for other patients who require it. We decompress the common boarding school, thus allowing us to have more beds and greater fluidity to satisfy the demand for hospitalization of patients with other pathologies[AU]

Introdução. Este espaço trata da utilização de bombas elastoméricas na administração de citostáticos de infusão contínua em pacientes oncológicos que recebem tratamento intravenoso, de infusão contínua de qmtem casa, melhorando assim a qualidade de vida do paciente, (esta experiência é apenas emrelação a aplicação de 5 fluorouracil). Material e método: No início, a primeira dose de quimioterapia é realizada no colégio interno comum para observar a tolerânciaao medicamento, e na segunda ou terceira aplicação é realizada em hospital dia a primeira parte do esquema, e em seguida, a bomba elastomérica é conectada, que fará a infusão de 5 fluorouracil por 46 horas. O paciente comparecerá ao hospital oncológico na hora 46 para realizar o desligamento. Nosso papel de enfermagem de contenção e treinamento é necessário a fim de garantir o correto manuseio do dispositivo e dar segurançaaos pacientes, para que alcancem um cuidado autônomo, seguro e eficaz. Para tal, é fornecido um manual de instruções. Ter Um catéter implantável é requisito obrigatório para esta modalidade; Benefícios encontrados: É portátil e ergonômico, melhora a mobilidade e o autocuidado, taxa de infusão exata. Recursos de segurança, incluindo proteção do reservatório contra possíveis danos; Descomprimimos internações, reduzimos a espera por leitos para admissão de pacientes .Reduzimos o uso de bombas elétricas comuns no internato, disponibilizando-as para outros pacientes internados. Dificuldades encontradas: Falta de conhecimento do paciente sobre o insumo (bomba). Insegurança do paciente ao estar em casa pela primeira vez. Procedimentos burocráticos para autorização da bomba. Conclusão. Esta implementação inovadora exige ainda mais aprendizagem, contamos com o apoio do Departamento de Enfermagem e do chefe do serviço de Oncologia-Dia Hospital, para utilização das bombas. Para esta experiencia foram utilizadas 10 bombas elastoméricas. Experiência prática, positiva para o paciente, ele também se compromete com o autocuidado e o tratamento, sendo possível evitar exposições nosocomiais, minimizando assim os riscos de contágio. Reduzimos o uso de bombas elétricas comuns no estágio, disponibilizando para outros pacientes que necessitem. Descomprimimos o internato comum, permitindo assim ter Mais leitos e maior fluidez para atender a demanda de internação de pacientes como utras patologias[AU]

Effect of double chain method on the closure of orthodontic teeth / 解剖学报

Objective To study the safety and effectiveness of the double chain method on the closure of the space of the teeth. Methods Totally 72 cases of different maxillary and mandible dentition space were included in the study. The pulp vitality was measured before and after treatment, the maxillary and mandible first molar teeth. All values were compared to assess the safety of dental pulp vitality. There were 36 cases in tooth extraction group and non-tooth extraction group.The observation period was 4 weeks, the changes of the alveolar space between maxillary and mandible teeth in adult and minor groups were measured before and after treatment. The difference of the total groove spacing before and after treatment were calculated and compared, to assess the effectiveness of space closure. Results In all 72 patients, there was no significant difference in the vitality of the pulp before and after treatment (P>0. 05). Compared to before treatment, the sum of the distance between the upper and lower mandibular groove using the double chain method was significantly reduced for both adult and juvenile patients in the four week tooth extraction group and the nontooth extraction group,the difference was statistically significant (P<0. 05). Conclusion Double chain closed teeth space does not cause pulp degeneration and necrosis. It is safe in clinical practice. Double chain method is effective, and can simplify the clinical operation.

Effect of Low Level Laser Therapy: A Novel Approach to Diminish Pain Associated With Elastomeric Separators

Background: Orthodontic pain usually appears hours after the force is applied. Methods employed for pain relief include nonsteroidal anti-inflammatory drugs, vibratory stimulation, chewing gum, anaesthetic gel, bite wafers, transcutaneous electrical nerve stimulation, and low level laser therapy. Aims and Objectives: To evaluate the effect of a single dose of low level laser therapy on pain associated with elastomeric separators. Methods: The sample comprised 30 patients. Elastomeric separators were placed mesial and distal to the permanent first molars in all quadrants. Both arches were divided into experimental and control sides. The experimental sides were treated with low-level laser therapy. The other side received placebo laser therapy without turning on the laser. A numeric rating scale was used to assess the intensity of spontaneous pain, pain after chewing, brushing, drinking water and warm drinks for five days. Results: There was a significant difference (P<0.05) between the laser and the placebo groups on spontaneous pain perceived by the patients for all 5 days. Conclusion: A single application of laser with a gallium aluminium- arsenic diode laser with a 980-nm wavelength can reduce orthodontic pain associated with the placement of separators

Comparison Of The Force Deterioration Of Different Orthodontic Elastomeric Materials In Artificial Saliva: An In Vitro Study

The orthodontist must be able to choose an elastic band with force-extension characteristics that are most suitable for the particular tooth movement required. From a clinician view it would be mandatory not only to know the clinical aspect of these elastics but also their basic properties, in order to extract the most out of these polymers. Stretching of elastics are thought to be the primary cause of force degradation of orthodontic elastics but there is evidence of in-creased force degradation of elastics when exposed to various types of substances like artificial saliva, phosphoric acid and citric acid. Orthodontic elastics have received mixed reactions of practitioners as reported by the vendors of ortho-dontic supplies. The present study is designed to compare the force deterioration of different orthodontic elastomeric materials in artificial saliva medium. There was a force deterioration over time in all materials, being greatest on the seventh day of the experiment, especially more in the chains; From the third to the fourth week there was no noticea-ble force degradation in either group; By the end of the experiment, modules showed less deterioration of the force compared to the chains and threads.

Effects of prestretch on stress relaxation and permanent deformation of orthodontic synthetic elastomeric chains / 대한치과교정학회지

OBJECTIVE: This study was performed to investigate an appropriate degree of prestretch for orthodontic synthetic elastomeric chains focusing on time-dependent viscoelastic properties. METHODS: Orthodontic synthetic elastomeric chains of two brands were prestretched to 50, 100, 150, and 200% of the original length in one and three cycles, and the hysteresis areas of the obtained stress-strain curves were determined. Acrylic plates were employed to maintain constant strain during the experiment. A total of 180 samples were classified into nine groups according to brand, and their stresses and permanent deformations were measured immediately after prestretch (0 hour), after 1 hour and 24 hours, and after 1, 2, 3, 4, 5, 6, 7, and 8 weeks. The relationship between stress relaxation and permanent deformation was investigated for various degrees of prestretch, and the estimated stress resulting from tooth movement was calculated. RESULTS: The degree of prestretch and the stress relaxation ratio exhibited a strong negative correlation, whereas no correlation was found between the degree of prestretch and the average normalized permanent strain. The maximal estimated stress was observed when prestretch was performed in three cycles to 200% of the original length. CONCLUSIONS: Although prestretch benefited residual stress, it did not exhibit negative effects such as permanent deformation. The maximal estimated stress was observed at the maximal prestretch, but the difference between prestretch and control groups decreased with time. In general, higher residual stresses were observed for product B than for product A, but this difference was not clinically significant.

Using Bio-Replicated Forming Technologies to Fabricate Shark-Skin Surface

ABSTRACT Shark-skin surfaces show the non-smoothness characteristics due to the presence of riblet structures. In this work, biomimetic shark-skins were prepared by means of different bio-replicated forming techniques. These techniques include the PDMS elastomeric stamping method (e.g., PES method) and the PDMS embedded-elastomeric stamping method (e.g., PEES method). The study characterized the fabricated biomimetic surfaces through the use of scanning electron microscopy (SEM) as well as 3D microscope. The accuracy of the two replication routes were compared, which included measuring the surface integrity and dimensional parameters ( s, h ) of the riblet-groove structure. The results show that fresh shark-skin without chemical treatments should be used as a replication template whenever possible to attain a satisfactory replication accuracy of the riblet structure. The PES and PEES methods proposed here are effective bio-replicated forming routes in simulating the microstructures of a shark-skin surface. Compared with the PES method, the PEES method has greater precision in simulating the microstructures of a shark-skin surface.

An innovative impression technique for fabrication of a custom made ocular prosthesis.

Various impression and fitting techniques have been described in the past for restoring ocular defects. The present article describes a new direct impression technique for recording and rehabilitating ocular defects, by custom‑made ocular prosthesis. All the techniques described in the history, mainly concentrated in recording the tissue surface of the defect, which made it difficult to contour the palpebral surface resulting in the poor esthetics of the prosthesis. The present impression technique uses heavy bodied polyvinyl siloxane impression material, which facilitates accurate recording of the tissue surface and the palpebral surface of the defect, resulting in the fabrication of functionally and esthetically acceptable prosthesis.

Enhancing retention of partial dentures using elastomeric retention rings.

This report presents an alternative method for the retention of partial dentures that relies on the engagement of tooth undercuts by a lining material. The lab procedures are also presented. A new maxillary and mandibular acrylic partial dentures were fabricated using elastomeric retention technique for a partially dentate patient. A partially dentate man reported difficulty in retaining his upper removable partial denture (RPD). The maxillary RPD was designed utilizing elastomeric retention technique. During follow‑up, it was necessary to replace the retention rings due to wear. The replacement of the retention rings, in this case, was done through a chairside reline technique. Elastomeric retention technique provides exceptionally good retention can be indicated to stabilize, cushion, splint periodontally involved teeth, no enough undercut for clasps, eliminate extractions, single or isolated teeth.

“Comparative evaluation of surface modified elastomeric ligatures for microbial colonization”: An in vivo study.

Introduction: Elastomeric ligatures are observed to reduce chair side time; however, they are also seen to have greater bacterial adhesion. Polymeric coating utilizing the Metafasix Technology and the OrthoShield Technology have been introduced in the Super Slick™* and Safe‑T‑Ties™** by TP Orthodontics, Ortho Organizers, respectively, to reduce bacterial adhesion. While each of the elastomers has been individually evaluated, no study compares the two elastomers manufactured by differing technologies together; hence the need for this study was felt. This in vivo study compared the Super Slick and Safe‑T‑Ties with their unmodified counterparts for bacterial adhesion. Materials and Methods: Thirty patients undergoing orthodontic treatment, between 12 and 25 years age group were selected and the modified, and the unmodified elastomers were randomly placed quadrant wise, on all the premolar brackets. After a period of 4 weeks, the elastomeric rings were removed and transported for culture on Mitis–Salivarius, Rogosa SL agar for Streptococcus mutans and Lactobacilli, respectively. The colonies were digitally counted (HiMedia) after 48 h of incubation at 37°C. Results: There was a significant difference in the S. mutans and Lactobacilli counts in both surface modified and unmodified elastomeric modules (P < 0.01). Unmodified elastomeric modules Mini Stix™*, Hand‑EE‑Lasts™** was associated with higher mean values of colony‑forming units/millimeter than the surface modified Super Slick™* and Safe‑T‑Ties™** ligatures. When compared pair‑wise, the surface modified elastomers showed less bacterial accumulations than the unmodified counterparts for both S. mutans and Lactobacillus, and the differences were statistically significant. Conclusion: Technological modifications of the elastomers using the Metafasix or OrthoShield Technology, is a definite improvement over the regular elastomers with regard to adhesion of S. mutans and Lactobacilli.

Does acidic drinks vs. controls differents interfere with the force of orthodontic chain elastics? / Bebidas ácidas versus diferentes controles interferem com a força de elásticos ortodônticos em cadeia?

This study aimed to investigate alterations in physical properties of orthodontic elastomeric chains when in contact with different controls and acidic beverages. Elastomeric chains were divided into 6 groups (n=18) of elastic chain segments, distributed as follows: Group CW (Deionized water) Group CS (Artificial saliva), Group CC (Coca-Cola®) Group SP (Sprite®) Group GA (Guaraná Antártica®) and Group FA(Fanta®). Elastics were stretched in 50% of the initial length and were held for initial, 1, 7, 14, 21 and 28 day time intervals. Force magnitudes were measured at 23.5 mm of activation using a digital meter. Force decay were assessed using analysis of variance(ANOVA) and Tukey's test(p<.05). Control Group CS saliva demonstrated the highest elastic decay values, with statistical difference between time of 24h with time intervals of 14, 21 and 28 days (p<.05). In comparison between groups, there was statistical difference between Group CS and Groups CW and FA in all experimental time-intervals, with group CC in time-intervals 7, 14, 21 and 28 days and with Group GA in time-intervals 7, 14 and 21 days (p<.05). In decreasing order: Coca-cola®, Fanta®, Guarana Antartica® and Sprite® demonstrated capacity to influence elastomeric chain decay, however with less influence than the saliva medium.

Este estudo objetivou investigar as alterações das propriedades físicas de cadeias elastoméricas ortodônticas quando em contato com diferentes controles e bebidas ácidas. Cadeias elastoméricas foram divididas em 6 grupos (n=18) de segmentos de elásticos em cadeia, assim distribuídos: Grupo CW (água deionizada), Grupo CS (saliva artificial), Grupo CC (Coca-Cola®), Grupo SP (Sprite®), Grupo GA (Guaraná Antártica®) e Grupo FA (Fanta®). Os elásticos foram esticados em 50 % do comprimento inicial e mantidos pelos intervalos de tempo inicial, 1, 7, 14, 21 e 28 dias. Magnitudes de força foram medidos em 23.5 mm de ativação usando um medidor digital. Degradação da Força foi avaliada através da análise de variância (ANOVA) e teste de Tukey (p<.05). Grupo Controle CS saliva demonstrou os maiores valores de degradação elástica, com diferença estatística entre o tempo de 24 h com intervalos de tempo de 14, 21 e 28 dias (p<.05). Na comparação entre os grupos, houve diferença estatística entre o Grupo CS e os Grupos CW e FA em todos os intervalos de tempos experimentais, com grupo CC nos intervalos de tempo de 7, 14, 21 e 28 dias e com o Grupo GA nos intervalos de tempo de 7, 14 e 21 dias (p<.05). Em ordem decrescente: Coca-cola®, Fanta®, Guaraná Antartica® e Sprite® demonstraram capacidade de influenciar a degradação da cadeia elastomérica, porém com menos influência do que o meio de saliva.

An in-vitro study to compare the force degradation of pigmented and non-pigmented elastomeric chains.

Aim: The purpose of the study was to compare the force delivery and force decay property of pigmented and non-pigmented elastomeric chains, widely used in orthodontic practice. Materials and Methods: Force delivered by the samples consisting of pigmented and non-pigmented elastomeric chains obtained from 3 manufacturers were tested at 3 time intervals (as received, after 24 hours and 21 days of stretching) to measure the force delivered by the test samples, as well as the force decay over time. Results: The force delivered by the non-pigmented samples was significantly greater than the pigmented ones at all 3 time intervals irrespective of the brand. Force decay was more significant in case of pigmented samples. Force decay was greater noticed in first 24 hours of testing and a gradual decrease in force was observed from 24 hours to 21 days in all test samples irrespective of the brand or color. Conclusion: Non-pigmented elastomeric chains exhibited better force delivery and less force decay percentage when compared to pigmented chains. Though colored elastomeric chains are widely used in present day orthodontic practice to satisfy the younger age group patients, the study ascertains the prudential use of pigmented and non-pigmented chains for efficient and faster orthodontic treatment.

Extracciones dentales atraumáticas en pacientes pediátricos con trastornos de la coagulación: descripción de la técnica y reporte de un caso / Atraumatic tooth extractions in pediatric patients with bleeding disorders: a technical description and report of a case

Se detalla y fundamenta la técnica de extracción atraumática de dientestemporales unirradiculares en pacientes pediátricos con trastornos de lacoagulación utilizando separadores elastoméricos. Se expone el caso deun paciente pediátrico con diagnóstico de defi ciencia de factor X de lacoagulación, quien requirió de la extracción atraumática de los órganosdentarios centrales superiores temporales debido a la gingivorragiapropia de la exfoliación natural.

We describe the technique of atraumatic tooth extraction for single-rooted temporary and permanent teeth in pediatric patients with bleed-ing disorders using elastomeric separators and discuss its benefi ts. We present the case of a pediatric patient diagnosed with coagulation factor X defi ciency who required the atraumatic extraction of his temporary upper central teeth due to gingival bleeding caused by natural exfoliation.

Hidrocompatibilidad de las siliconas por condensación de consistencia liviana / Hydrocompatibility of the silicones by condensation of light consistency

Objetivo. Evaluar la capacidad de hidrocompatibilidad de las siliconas por condensación de consistencia liviana, de acuerdo al ángulo de contacto. Material y métodos. Se realizó un estudio descriptivo, comparativo con la finalidad de evaluar la capacidad de hidrocompatibilidad de tres siliconas por condensación para ello se diseñaron 3 cuerpos de prueba de forma rectangular de 1 cm de espesor y 10 cm de largo, utilizando moldes de aluminio fabricados para este fin. Se llenaron los moldes con diferentes marcas comerciales de silicona liviana por condensación (Orange wash, Speedex y lastic 90 Fine). Sobre la superficie de la silicona se depositó una gota de agua destilada de 10 uL. de volumen utilizando una micropipeta Boeco y se tomaron fotografías de esta a los 0, 10 y 30 segundos. La experiencia se realizó 10 veces en cada cuerpo de prueba, siempre en un área limpia, de forma que se obtuvieron 30 fotografías por cada marca de silicona. Posteriormente, las imágenes fueron procesadas en un software para medir el ángulo de contacto a cada lado de la gota de agua (tpsDig), por lo que finalmente se consiguieron 60 mediciones por cuerpo de prueba (20 por cada tiempo considerado). Para determinar la hidrocompatibilidad se realizó el análisis estadístico media aritmética y desviación estándar. Resultados. El análisis descriptivo de los datos mostró que la silicona por condensación de consistencia liviana Speedex mostró un mejor comportamiento respecto a la disminución del ángulo de contacto y humectabilidad de superficie con el paso del tiempo tanto a los 10 y 30 segundos, seguido por la silicona Orange wash. La silicona Lastic 90 Fine presentó una pobre hidrocompatibilidad ya que su ángulo de contacto permaneció inalterable a pesar del paso de tiempo. Conclusiones. Existen diferencias marcadas respecto a la hidrocompatibilidad de los diferentes materiales utilizados en este estudio. La silicona que presento mejor hidrocompatibilidad fue la Speedex ...

Objective.To evaluate the capacity of hidrocompatibility of the silicones by condensation of light consitency, according to the contact angle. Material and methods. A descriptive, comparative study was made with the purpose of evaluating the capacity of hidrocompatibility of three silicones by condensation, for this reason, 3 bodies of test of rectangular form with a thickness of 1 cm and a length of 10 cm were designed, using molds of aluminium made for this use. The molds were filled by different commercial brands of light silicone by condensation (Orange wash, Speedex and lastic 90 Fine). On the surface of the silicone a drop of distilled water of 10 uL of volume was deposited ,using a micropipette Boeco and photographies of this was one was taken at 0, 10 and 30 seconds. The experience was made 10 times in every body of test, always in a clean area, there were taken 30 photographies by every brand of silicone. Then, the images were processed in software to measure the contact angle to every side of the water drop (tpsDig); finally 60 measurements were obtained by body of test (20 in each time). To evaluate hydrocompatibility, there were made statistical analysis using arithmetic mean and standard deviation. Results. The descriptive analysis of the data showed that the silicone by light condensation Speedex had a better behavior with regard to the decrease of the contact angle and surface wettability with the time, from 10 to 30 seconds, followed by the silicone Orange wash. The silicone Lastic 90 Fine showed a poor hydrocompatibility and its contact angle remained without changes in spite of the time. Conclusions. There are differences with regard to the hydrocompatibility of the different materials used in this study. Silicone that shows a better hydrocompatibility was the brand Speedex while the brand Lastic 90 Fine showed worst results with regard to the contact angle.