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1.
Dental Press J Orthod ; 26(1): e2119150, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33729290

RESUMO

INTRODUCTION: Third generation of LED light curing units might be used in short exposure periods for orthodontic brackets bonding. OBJECTIVE: This study evaluated the effect of the different radiant exposure (RE) values: Manufacturers' instructions (MI), ½ MI, 1/4 MI and Turbo mode. Two third-generation LED curing units were used: VALO® and Bluephase 20i® . The degree of conversion (DC) and Vickers hardness (VHN) of an orthodontic composite (OC) (Transbond XT) under metallic (MB) or ceramic brackets (CB) were measured. METHODS: OC was applied to the bracket base, which was then placed over an attenuated total reflectance (ATR) table coupled to an infrared light spectroscope, or to a glass surface for the VHN analysis. The specimens were light-cured and DC values were calculated. The VHN was obtained in a microhardness tester. The data were analyzed with 2-way ANOVA followed by Tukey's post-hoc test (pre-set α=0.05). Linear regression analysis evaluated the relationship between RE values and dependent variables. RESULTS: CB allowed higher DC and VHN values than MB (p< 0.001). No significant difference was noted among groups when CB were used. For MB, MI groups showed the highest DC and VHN values. A significant, but weak relationship was found between delivered RE values and dependent variables. CONCLUSIONS: The decrease in RE values from third generation LED CU did not jeopardize the DC values when CB were used, but can compromise DC and VHN values when MB are used.


Assuntos
Luzes de Cura Dentária , Braquetes Ortodônticos , Cerâmica , Resinas Compostas , Dureza , Teste de Materiais , Polimerização , Cimentos de Resina , Propriedades de Superfície
2.
Dental press j. orthod. (Impr.) ; 26(1): e2119150, 2021. tab, graf
Artigo em Inglês | LILACS, BBO - Odontologia | ID: biblio-1154070

RESUMO

ABSTRACT Introduction: Third generation of LED light curing units might be used in short exposure periods for orthodontic brackets bonding. Objective: This study evaluated the effect of the different radiant exposure (RE) values: Manufacturers' instructions (MI), ½ MI, 1/4 MI and Turbo mode. Two third-generation LED curing units were used: VALO® and Bluephase 20i® . The degree of conversion (DC) and Vickers hardness (VHN) of an orthodontic composite (OC) (Transbond XT) under metallic (MB) or ceramic brackets (CB) were measured. Methods: OC was applied to the bracket base, which was then placed over an attenuated total reflectance (ATR) table coupled to an infrared light spectroscope, or to a glass surface for the VHN analysis. The specimens were light-cured and DC values were calculated. The VHN was obtained in a microhardness tester. The data were analyzed with 2-way ANOVA followed by Tukey's post-hoc test (pre-set α=0.05). Linear regression analysis evaluated the relationship between RE values and dependent variables. Results: CB allowed higher DC and VHN values than MB (p< 0.001). No significant difference was noted among groups when CB were used. For MB, MI groups showed the highest DC and VHN values. A significant, but weak relationship was found between delivered RE values and dependent variables. Conclusions: The decrease in RE values from third generation LED CU did not jeopardize the DC values when CB were used, but can compromise DC and VHN values when MB are used.


RESUMO Introdução: A terceira geração de LEDs fotopolimerizadores pode ser utilizada em curtos períodos de exposição para a colagem de braquetes ortodônticos. Objetivo: O presente estudo avaliou o efeito dos diferentes valores de irradiância (IR): instruções do fabricante (IF), ½ IF, » IF e modo Turbo. Dois fotopolimerizadores LED de terceira geração (VALO® e Bluephase20i®) foram utilizados. Foram mensurados o grau de conversão (GC) e a dureza Vickers (VHN) de um compósito ortodôntico (CO) (Transbond XT) sob braquetes metálicos (BM) ou cerâmicos (BC). Métodos: O compósito ortodôntico foi aplicado na base do braquete e foi posicionado sobre uma mesa de refletância total atenuada (ATR) acoplada a um espectroscópio de infravermelho ou a uma superfície de vidro para análise de VHN. As amostras foram fotopolimerizadas e os valores de GC foram calculados. O VHN foi obtido em um microdurômetro. Os dados foram analisados com ANOVA de 2 fatores seguida do teste post-hoc de Tukey (predefinido α = 0,05). A análise de regressão linear avaliou a relação entre os valores de IR e as variáveis dependentes. Resultados: BC permitiu valores maiores de GC e VHN do que BM (p<0,001). Nenhuma diferença significativa foi observada entre os grupos quando BC foi utilizado. Para BM, os grupos de IF mostraram os maiores valores de GC e VHN. Uma relação significativa, mas fraca, entre os valores de IR entregue e as variáveis dependentes foi encontrada. Conclusões: A diminuição dos valores de IR dos fotopolimerizadores LED de terceira geração não prejudicou os valores de GC quando BC foram utilizados, mas pode comprometer os valores de GC e VHN quando BM são utilizados.


Assuntos
Cerâmica , Braquetes Ortodônticos , Resinas Compostas , Luzes de Cura Dentária , Propriedades de Superfície , Teste de Materiais , Cimentos de Resina , Polimerização , Dureza
3.
Dent Mater ; 36(9): 1201-1213, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32576408

RESUMO

OBJECTIVE: To evaluate the influence of light emitted from two Polywave®, LED light-curing units (LCU) on in vivo pulp temperature (PT) rise and signs of acute inflammatory response in pulps of human premolar having deep Class V preparations. METHODS: Sixty intact, first premolars from 15 volunteers requiring extraction received infiltrative anesthesia. A sterile thermocouple probe was inserted within the pulp tissue through a minute occlusal pulp exposure in only 45 teeth (n = 9) to continuously monitor PT (°C). A deep buccal Class V preparation was created, and the surface was exposed to light from a commercial Polywave LCU (Bluephase 20i (20i), Ivoclar Vivadent) or from an experimental LCU (Exp) using the exposure modes (EM): 1s/Exp and 2s/Exp, 10s/20i, 20s/20i, and 60s/20i. Peak PT and PT rise values above baseline (ΔT) data were evaluated using a one-way ANOVA followed by Tukey's post-hoc test (α = 5%). Teeth used for histological and immunohistochemical analyses (n = 3) were extracted approximately 2 h after exposure to the LCU. RESULTS: No significant difference in peak PT and ΔT values was noted between 2s/Exp and 20s/20i groups, which both exhibited higher values than 1s/Exp and 10s/20i groups (p < 0.001). Dilated and congested blood vessels were seen after exposure to 1s/Exp, 2s/Exp, or 60s/20i EMs. The expression of IL-1ß and TNF-α tended to be more intense when higher irradiance was delivered. SIGNIFICANCE: Although higher irradiance delivered over a short exposure caused lower PT rise than 5.5 °C, such EMs should be used with caution, as they have more potential to harm the pulp tissue.


Assuntos
Luzes de Cura Dentária , Cura Luminosa de Adesivos Dentários , Dente Pré-Molar , Resinas Compostas , Polpa Dentária , Humanos , Temperatura
4.
Prosthes. Esthet. Sci ; 8(31): 54-62, abr./mai./jun. 2019.
Artigo em Português | BBO - Odontologia | ID: biblio-1016200

RESUMO

A era digital da odontologia e as ferramentas disponíveis no mercado para o planejamento de casos clínicos proporcionam novas possibilidades de diagnóstico e de plano de tratamento. Com isso, é possível o planejamento dos diversos casos clínicos digitalmente, permitindo um workflow no qual as diversas áreas da odontologia podem interagir, proporcionando para o paciente e os clínicos melhor prognóstico, maior agilidade e precisão nos diversos procedimentos, sendo eles menos invasivos; ou até mesmo tratamento mais complexos dentro das diversas áreas da odontologia como a ortodontia, periodontia, cirurgias, procedimentos restaurativos ou protéticos. Este artigo relata um caso clínico realizado com fluxo digital e aborda alguns temas referentes ao passado, presente e futuro da era digital na odontologia. (AU).


The digital era of dentistry and the tools available in the market provide new possibilities for clinical planning, diagnosis, and treatment plan. These permit to plan the various clinical cases digitally, allowing a workflow in which the different áreas of dentistry can Interact. Their implementation can lead to two desired outcomes. First, better diagnosis for patients and clinicians, more expedited diagnoses, and more precise procedures. Second, less invasive procedures within complex treatments in orthodontics, periodontics, surgery, and dental restoration. This article Will report a clinical case carried out with digital flow and Will address some issues related to the past, present, and future of the digital age in dentistry.


Assuntos
Humanos , Masculino , Adulto , Prostodontia , Tecnologia Odontológica , Estética Dentária
5.
J Appl Oral Sci ; 27: e20180480, 2019 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-31116279

RESUMO

OBJECTIVES: To measure and compare in vivo and in vitro pulp temperature (PT) increase (ΔTEMP) over baseline, physiologic temperature using the same intact upper premolars exposed to the same Polywave® LED curing light. METHODOLOGY: After local Ethics Committee approval (#255,945), local anesthesia, rubber dam isolation, small occlusal preparations/minute pulp exposure (n=15) were performed in teeth requiring extraction for orthodontic reasons. A sterile probe of a temperature measurement system (Temperature Data Acquisition, Physitemp) was placed within the pulp chamber and the buccal surface was sequentially exposed to a LED LCU (Bluephase 20i, Ivoclar Vivadent) using the following exposure modes: 10-s low or high, 5-s Turbo, and 60-s high. Afterwards, the teeth were extracted and K-type thermocouples were placed within the pulp chamber through the original access. The teeth were attached to an assembly simulating the in vivo environment, being similarly exposed while real-time temperature (°C) was recorded. ΔTEMP values and time for temperature to reach maximum (ΔTIME) were subjected to two-way ANOVA and Bonferroni's post-hoc tests (pre-set alpha 0.05). RESULTS: Higher ΔTEMP was observed in vitro than in vivo. No significant difference in ΔTIME was observed between test conditions. A significant, positive relationship was observed between radiant exposure and ΔTEMP for both conditions (in vivo: r2=0.917; p<0.001; in vitro: r2=0.919; p<0.001). CONCLUSION: Although the in vitro model overestimated in vivo PT increase, in vitro PT rise was close to in vivo values for clinically relevant exposure modes.


Assuntos
Luzes de Cura Dentária , Polpa Dentária/efeitos da radiação , Temperatura , Análise de Variância , Luzes de Cura Dentária/efeitos adversos , Humanos , Técnicas In Vitro , Doses de Radiação , Exposição à Radiação , Valores de Referência , Análise de Regressão , Reprodutibilidade dos Testes , Fatores de Tempo
6.
J. appl. oral sci ; 27: e20180480, 2019. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1002402

RESUMO

Abstract Objectives: To measure and compare in vivo and in vitro pulp temperature (PT) increase (ΔTEMP) over baseline, physiologic temperature using the same intact upper premolars exposed to the same Polywave® LED curing light. Methodology: After local Ethics Committee approval (#255,945), local anesthesia, rubber dam isolation, small occlusal preparations/minute pulp exposure (n=15) were performed in teeth requiring extraction for orthodontic reasons. A sterile probe of a temperature measurement system (Temperature Data Acquisition, Physitemp) was placed within the pulp chamber and the buccal surface was sequentially exposed to a LED LCU (Bluephase 20i, Ivoclar Vivadent) using the following exposure modes: 10-s low or high, 5-s Turbo, and 60-s high. Afterwards, the teeth were extracted and K-type thermocouples were placed within the pulp chamber through the original access. The teeth were attached to an assembly simulating the in vivo environment, being similarly exposed while real-time temperature (°C) was recorded. ΔTEMP values and time for temperature to reach maximum (ΔTIME) were subjected to two-way ANOVA and Bonferroni's post-hoc tests (pre-set alpha 0.05). Results: Higher ΔTEMP was observed in vitro than in vivo. No significant difference in ΔTIME was observed between test conditions. A significant, positive relationship was observed between radiant exposure and ΔTEMP for both conditions (in vivo: r2=0.917; p<0.001; in vitro: r2=0.919; p<0.001). Conclusion: Although the in vitro model overestimated in vivo PT increase, in vitro PT rise was close to in vivo values for clinically relevant exposure modes.


Assuntos
Humanos , Temperatura , Polpa Dentária/efeitos da radiação , Luzes de Cura Dentária/efeitos adversos , Doses de Radiação , Valores de Referência , Fatores de Tempo , Técnicas In Vitro , Análise de Regressão , Reprodutibilidade dos Testes , Análise de Variância , Exposição à Radiação
7.
Dent Mater ; 34(6): 901-909, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29606368

RESUMO

OBJECTIVE: This in vivo study evaluated pulp temperature (PT) rise in human premolars having deep Class V preparations during exposure to a light curing unit (LCU) using selected exposure modes (EMs). METHODS: After local Ethics Committee approval, intact first premolars (n=8) requiring extraction for orthodontic reasons, from 8 volunteers, received infiltrative and intraligamental anesthesia and were isolated using rubber dam. A minute pulp exposure was attained and sterile probe from a wireless, NIST-traceable, temperature acquisition system was inserted into the coronal pulp chamber to continuously monitor PT (°C). A deep buccal Class V preparation was prepared using a high speed diamond bur under air-water spray cooling. The surface was exposed to a Polywave® LED LCU (Bluephase 20i, Ivoclar Vivadent) using selected EMs, allowing 7-min span between each exposure: 10-s in low (10-s/L), 10-s (10-s/H), 30-s (30-s/H), or 60-s (60-s/H) in high mode; and 5-s-Turbo (5-s/T). Peak PT values and PT increases over physiologic baseline levels (ΔT) were subjected to 1-way, repeated measures ANOVAs, and Bonferroni's post-hoc tests (α=0.05). Linear regression analysis was performed to establish the relationship between applied radiant exposure and ΔT. RESULTS: All EMs produced higher peak PT than the baseline temperature (p<0.001). Only 60-s/H mode generated an average ΔT of 5.5°C (p<0.001). A significant, positive relationship was noted between applied radiant exposure and ΔT (r2=0.8962; p<0.001). SIGNIFICANCE: In vivo exposure of deep Class V preparation to Polywave® LED LCU increases PT to values considered safe for the pulp, for most EMs. Only the longest evaluated EM caused higher PT increase than the critical ΔT, thought to be associated with pulpal necrosis.


Assuntos
Luzes de Cura Dentária , Preparo da Cavidade Dentária/métodos , Polpa Dentária/efeitos da radiação , Dente Pré-Molar , Temperatura Alta , Humanos , Extração Dentária
8.
Ortho Sci., Orthod. sci. pract ; 11(41): 28-32, 2018. ilus, tab, graf
Artigo em Português | BBO - Odontologia | ID: biblio-882315

RESUMO

Este estudo avaliou o grau de conversão de uma resina composta utilizada em tratamentos restauradores, Filtek Z 250 - 3M ESPE (Z250), e duas resinas ortodônticas: Orthocem - FGM (OC) e Transbond XT - 3M Unitek (TB) por meio da espectroscopia no infravermelho por transformada de Fourier (FTIR). Para isto, foram confeccionados quinze corpos de prova fotopolimerizados para cada resina. As medidas de grau de conversão foram realizadas imediatamente após a confecção das amostras. Os espectros de absorção no infravermelho foram obtidos num espectrofotômetro Parkin Elmer do Brasil. Os resultados das amostras tiveram sua normalidade aferida por meio do teste Kolmogorov-Smirnov e analisadas pelo teste ANOVA um critério, que demonstrou haver diferença estatística entre os grupos (p<0,05). (AU)


This study evaluated the degree of conversion of a composite resin used in restorative treatments, Filtek Z 250 - 3M ESPE (Z250), and two orthodontic resins: Orthocem - FGM (OC) and Transbond XT - 3M Unitek (TB) by means of infrared spectroscopy Fourier transform (FTIR). For this, fifteen bodies of light cured specimens were fabricated for each resin. Measures of degree of conversion were performed immediately after preparation of the samples. The infrared absorption spectra were obtained on a Parkin Elmer spectrophotometer Brazil. The results of the samples were measured using normality of the Kolmogorov-Smirnov test and analyzed by ANOVA criterion, which showed no statistical difference between groups (p<0,05). (AU)


Assuntos
Resinas Compostas , Cimentos Dentários , Cura Luminosa de Adesivos Dentários , Ortodontia
9.
Imaging Sci Dent ; 46(1): 17-24, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27051635

RESUMO

PURPOSE: This study employed a posteriori registration and subtraction of radiographic images to quantify the apical root resorption in maxillary permanent central incisors after orthodontic treatment, and assessed whether the external apical root resorption (EARR) was related to a range of parameters involved in the treatment. MATERIALS AND METHODS: A sample of 79 patients (mean age, 13.5±2.2 years) with no history of trauma or endodontic treatment of the maxillary permanent central incisors was selected. Periapical radiographs taken before and after orthodontic treatment were digitized and imported to the Regeemy software. Based on an analysis of the posttreatment radiographs, the length of the incisors was measured using Image J software. The mean EARR was described in pixels and relative root resorption (%). The patient's age and gender, tooth extraction, use of elastics, and treatment duration were evaluated to identify possible correlations with EARR. RESULTS: The mean EARR observed was 15.44±12.1 pixels (5.1% resorption). No differences in the mean EARR were observed according to patient characteristics (gender, age) or treatment parameters (use of elastics, treatment duration). The only parameter that influenced the mean EARR of a patient was the need for tooth extraction. CONCLUSION: A posteriori registration and subtraction of periapical radiographs was a suitable method to quantify EARR after orthodontic treatment, and the need for tooth extraction increased the extent of root resorption after orthodontic treatment.

10.
Ortho Sci., Orthod. sci. pract ; 9(34): 89-95, 2016.
Artigo em Português | LILACS, BBO - Odontologia | ID: biblio-831167

RESUMO

Este artigo reporta o caso clínico de um paciente do gênero feminino, com 53 anos, portadora de má oclusão Classe II subdivisão esquerda, com mordida aberta anterior esquelética. O tratamento foi realizado com a intrusão dos dentes posteriores superiores e inferiores, por meio da ancoragem esquelética com quatro miniplacas. Os resultados demonstraram a intrusão dos molares superiores e inferiores, distalização dos molares superiores do lado esquerdo, rotação anti-horária da mandíbula, com diminuição da altura facial inferior, correção da mordida aberta anterior e da Classe II subdivisão esquerda.


This article reports the clinical case of a 53 years old female patient, with Angle Class II subdivision left, with skeletal anterior open bite. The treatment was performed with the intrusion of maxillary and mandibular posterior teeth, by skeletal anchorage with four miniplates. The results showed the intrusion of upper and lower molars distalization of upper molars on the left, counterclockwise rotation of the mandible, with decreased lower facial height, correction of anterior open bite, and Class II subdivision left.


Assuntos
Feminino , Mordida Aberta , Procedimentos de Ancoragem Ortodôntica , Ortodontia Corretiva
11.
Dent Mater ; 31(5): 505-13, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25711700

RESUMO

OBJECTIVES: This in vivo study evaluated pulp temperature (PT) rise in human premolars during exposure to a light curing unit (LCU) using selected exposure modes (EMs). METHODS: After local Ethics Committee approval, intact first upper premolars, requiring extraction for orthodontic reasons, from 8 volunteers, received infiltrative and intraligamental anesthesia. The teeth (n=15) were isolated using rubber dam and a minute pulp exposure was attained. A sterile probe from a wireless, NIST-traceable, temperature acquisition system was inserted directly into the coronal pulp chamber, and real time PT (°C) was continuously monitored while the buccal surface was exposed to polywave light from a LED LCU (Bluephase 20i, Ivoclar Vivadent) using selected EMs allowing a 7-min span between each exposure: 10-s either in low (10-s/L) or high (10-s/H); 5-s-turbo (5-s/T); and 60-s-high (60-s/H) intensities. Peak PT values and PT increases from baseline (ΔT) after exposure were subjected to one-way, repeated measures ANOVAs, and Bonferroni's post hoc tests (α=0.05). Linear regression analysis was performed to establish the relationship between applied radiant exposure and ΔT. RESULTS: All EMs produced higher peak PT than the baseline temperature (p<0.001). The 60-s/H mode generated the highest peak PT and ΔT (p<0.001), with some teeth exhibiting ΔT higher than 5.5°C. A significant, positive relationship between applied radiant exposure and ΔT (r(2)=0.916; p<0.001) was noted. SIGNIFICANCE: Exposing intact, in vivo anesthetized human upper premolars to a polywave LED LCU increases PT, and depending on EM and the tooth, PT increase can be higher than the critical ΔT, thought to be associated with pulpal necrosis.


Assuntos
Temperatura Corporal/fisiologia , Luzes de Cura Dentária , Polpa Dentária/fisiologia , Adolescente , Adulto , Anestesia Dentária , Dente Pré-Molar , Criança , Feminino , Humanos , Masculino
12.
Dent Mater ; 31(1): 53-9, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25483936

RESUMO

OBJECTIVES: Human intrapupal tooth temperature is considered to be similar to that of the body (≈37 °C), although the actual temperature has never been measured. This study evaluated the in vivo, human, basal, coronal intrapulpal temperature of anesthetized upper first premolars. METHODS: After approval of the local Ethics Committee was obtained (protocol no. 255,945), upper right and left first premolars requiring extraction for orthodontic reasons from 8 volunteers, ranging from 12 to 30 years old, received infiltrative and intraligamental anesthesia. The teeth (n=15) were isolated using rubber dam and a small, occlusal preparation was made using high-speed handpiece, under constant air-water spray, until a minute pulp exposure was attained. The sterile probe from a wireless, NIST-traceable, temperature acquisition system (Thermes WFI) was inserted directly into the coronal pulp. Once the probe was properly positioned and stable, real-time temperature data were continuously acquired for approximately 25 min. Data (°C) were subjected to 2-tailed, paired t-test (α=0.05), and the 95% confidence intervals for the initial and 25-min mean temperatures were also determined. RESULTS: The initial pulp temperature value (31.8±1.5 °C) was significantly lower than after 25-min (35.3±0.7 °C) (p<0.05). The 95% confidence interval for the initial temperature ranged from 31.0 to 32.6 °C and from 35.0 to 35.7 °C after 25 min. A slow, gradual temperature increase was observed after probe insertion until the pulp temperature reached a plateau, usually after 15 min. SIGNIFICANCE: Consistent coronal, human, in vivo temperature values were observed and were slightly, but significantly below that of body core temperature.


Assuntos
Anestesia Dentária , Temperatura Corporal/fisiologia , Preparo da Cavidade Dentária/métodos , Equipamentos Odontológicos de Alta Rotação , Polpa Dentária/fisiologia , Adolescente , Adulto , Preparo da Cavidade Dentária/instrumentação , Feminino , Humanos , Técnicas In Vitro , Masculino , Extração Dentária
13.
Ortho Sci., Orthod. sci. pract ; 8(30): 148-153, 2015. tab, graf
Artigo em Português | LILACS | ID: lil-761277

RESUMO

Este estudo comparou duas diferentes máquinas de ensaio mecânico (Shimadzu e Kratos), com ou sem a realização da termociclagem, na leitura da resistência adesiva ao cisalhamento (RAC) e do índice de adesivo remanescente (IAR) após a descolagem de bráquetes metálicos colados com resina Transbond XT. Foram utilizados 60 pré-molares humanos, nos quais foram colados bráquetes metálicos, divididos aleatoriamente em dois grupos: Grupo I – com termociclagem (500 ciclos) entre 5º e 55ºC e Grupo II – sem termociclagem. Estes grupos foram subdivididos em quatro subgrupos (n=15). Foi realizado o teste mecânico de cisalhamento com ambas as máquinas: subgrupos I A (Shimadzu) e I B (Kratos) e subgrupos II A (Shimadzu) e II B (Kratos). As amostras foram submetidas aos ensaios mecânicos de cisalhamento com velocidade de carga de 0,5 mm/min. Os resultados da RAC foram submetidos ao teste de normalidade de D’Agostino & Pearson, ANOVA - 1 Critério (a = 0,05), pós-teste de Tukey e os dados do IAR ao teste de Kruskal-Wallis (a = 0,05). Não foram encontradas diferenças estatisticamente significativas entre os subgrupos. Conclui-se que a utilização de diferentes tipos de máquinas de ensaio, com ou sem termociclagem, não apresentam diferenças estatísticas na leitura da resistência ao cisalhamento ou do índice de adesivo remanescente...


This study has compared two different mechanical testing machine (Shimadzu and Kratos), with or without performing of thermocycling, the reading of the adhesive shear strength (RAC) and the adhesive remnant index (ARI), after debonding of metal brackets bonded with Transbond XT resin. Metal brackets were bonded on sixty human premolars that were then randomly divided into two groups: Group I - with thermocycling (500 cycles) between 5 and 55ºC and Group II - without thermocycling. These groups were divided into four subgroups (n = 15). Test was performed with both mechanical shearing machines: subgroups I A (Shimadzu) and I B (Kratos) and subgroups II A (Shimadzu) and II B (Kratos). Samples were submitted to shear bond strength (SBS) testing with a crosshead speed of 0.5 mm/min. The results of the SBS were tested for normality D’Agostino & Pearson, test 1 way ANOVA (a = 0.05), Tukey post-test. Data from the ARI were submitted to the Kruskal-Wallis test (a = 0.05). There was no statistically significant difference between subgroups. There was no statistically significant difference between subgroups. It was concluded that the use of different types of test machines, with or without thermocycling did not show statistical differences in reading shear bond strength or adhesive remnant index...


Assuntos
Humanos , Criança , Adolescente , Esmalte Dentário , Remoção , Braquetes Ortodônticos , Resistência ao Cisalhamento
14.
Ortho Sci., Orthod. sci. pract ; 7(25): 43-50, 2014. ilus, tab, graf
Artigo em Português | LILACS, BBO - Odontologia | ID: lil-729347

RESUMO

Na descolagem de bráquetes ortodônticos pode ocorrer a perda de esmalte na interface adesivo-esmalte. O objetivo deste estudo foi avaliar os possíveis danos à superfície do esmalte com recolagens de bráquetes metálicos e cerâmicos novos por meio da resistência adesiva ao cisalhamento (RAC), da análise do índice de adesivo remanescente (IAR), da avaliação da rugosidade de superfície (RA) e pela análise de microscopia eletrônica (MEV). Foram usados 120 pré-molares, divididos aleatoriamente em 4 grupos de 30 dentes: CS (Controle Saliva); CA (Condicionamento Ácido); M (Metálico) e C (Cerâmico). Foram colados 120 bráquetes metálicos e 120 cerâmicos, para os grupos M e C, em quatro tempos. Os ensaios mecânicos foram realizados em máquina SHIMADZU, na velocidade 0,5 mm/min. Na avaliação da RAC, o ANOVA a dois critérios demonstrou não haver diferenças (p= 0,052) entre os grupos. Na avaliação do IAR, o teste U de Mann-Whitney demonstrou diferença entre os grupos (p< 0,001), onde o grupo cerâmico exibiu escores mais altos que o metálico. Para a rugosidade, o ANOVA a um critério demonstrou que o grupo M apresentou maior RA (p< 0,001). O teste de Tukey demonstrou que os grupos M e C, após o polimento com discos Sof-Lex, exibiram valores de rugosidade inferiores aos demais grupos. Conclui-se que na remoção de bráquetes metálicos ou cerâmicos e da resina remanescente existe maior risco de danos ao esmalte nas recolagens sucessivas. O polimento com discos Sof-Lex promoveu superfície com maior lisura do esmalte.


Debonding of orthodontic brackets may cause enamel surface loss primarily at the adhesive-enamel interface. The purpose of the present study was to evaluate by means of shear bond strength (SBS), adhesive remnant index (ARI), assessment of surface roughness and electron microscope analysis, the possible damages at enamel surface with repeated rebonding of new metallic and ceramic brackets. One hundred and twenty human premolars were randomly divided into 4 groups of 30 premolars each: CS (Saliva Control); CA (Acid Etching); M (Metal); C (Ceramic). For CA group, 4 repeated acid conditionings were performed. One hundred and twenty metallic and ceramic brackets, for groups M and C, were bonded and rebonded respectively at 4 stages. Mechanical trials were obtained with a SHIMADZU testing machine at 0.5 mm/min cross-speed. The SBS results were statistically tested with ANOVA, and no statistically significant differences (p=0.052) were observed. The ARI was evaluated by Mann-Whitney test, which demonstrated that there was a statistically significant difference between metallic and ceramic brackets (p<0.001). The ceramic group exhibited higher statistically significant scores for ARI than the metallic group. The roughness assessment was made with one-way ANOVA, that showed statistically significant differences between groups (p<0.001). Tukey´s test has demonstrated that the M and C groups that were polished with SofLex discs had statistically significant lower roughness values as compared to other groups. Polishing with Sof-lex discs, lead to increased smoothness of enamel surfaces.


Assuntos
Humanos , Adolescente , Esmalte Dentário , Braquetes Ortodônticos
15.
Ortho Sci., Orthod. sci. pract ; 7(25): 27-32, 2014. ilus, tab, graf
Artigo em Português | LILACS, BBO - Odontologia | ID: lil-729349

RESUMO

O objetivo deste estudo foi avaliar em diferentes resinas ortodônticas a microdureza Vickers e o grau de conversão. Quatro resinas foram utilizadas: Orthobond (OB), Ortholite (OL), Concise (CO) e Transbond XT (TB). Para cada resina, cinco amostras foram obtidas, nas quais foram realizadas trinta endentações em cada superfície no microdurômetro Shimadzu (carga de 300 gramas/15 segundos). Para a avaliação do grau de conversão, duas amostras de cada monômero e polímero foram obtidas e submetidas ao ensaio de FTIR pelo método de transmissão, com resolução 2 cm-1 e 40 varreduras. Os resultados de microdureza Vickers (µHV) e grau de conversão (%) foram, respectivamente, para OB: 46 ± 17.52 (70% ±1.41), OL: 71 ±28.15 (61% ±3.53), CO: 76 ±32.70 (70% ±0.35) e TB: 73±28.40 (60% ±9.89). Os dados da µHV foram submetidos ao Teste de ANOVA e pós teste de Tukey, não apresentando diferenças estatísticas significantes entre as resinas. O conhecimento das propriedades físicas entre as resinas pode facilitar a escolha do material utilizado nos procedimentos ortodônticos.


The aim of this study was to evaluate Vickers microhardness and the degree of conversion of different orthodontic resins. Four resins were used: Orthobond (OB), Ortholite (OL), Concise (CO), and Transbond XT (TB). For each resin five samples were obtained, in which thirty indentations were made on each surface in Shimadzu microhardness (300 grams/15 seconds). To assess the degree of conversion, two samples of each monomer and polymer materials were obtained and submitted to the test of FTIR Spectrophotometry by method of transmission, toned down with resolution 2 cm-1 and 40 scans. The results of Vickers microhardness (µ HV) and degree of conversion (%) were, respectively OB: 46 ± 17.52 (70% ± 1.41); OL: 71 ± 28.15 (61% ± 3.53); CO: 76 ± 32.70 (70% ± 0.35); TB: 73 ± 28.40 (60% ± 9.89). The data were submitted to ANOVA test and Tukey post-test, and no significant statistical differences were observed between the resins. The knowledge of the physical properties between resins can facilitate the choice of the material used in orthodontic procedures.


Assuntos
Bis-Fenol A-Glicidil Metacrilato , Colagem Dentária , Testes de Dureza , Ortodontia
16.
Ortho Sci., Orthod. sci. pract ; 7(26): 167-172, 2014. ilus, tab
Artigo em Português | LILACS, BBO - Odontologia | ID: lil-729977

RESUMO

Uma higiene bucal deficiente favorece o acúmulo de placa bacteriana e o início de inflamação gengival. O uso de aparelhos ortodônticos tem um grande impacto sobre a microbiota bucal porque fornece sítios extras de adesão bacteriana. O uso de substâncias químicas vem sendo empregado com o objetivo de inibir a formação de biofilme dental, crescimento bacteriano e a adesão de bactérias às superfícies. O presente estudo comparou a aderência de bactérias em ligaduras da marca Morelli® e OrthoSource® e a potencial desinfecção pelos colutórios: Plax Ice®, Listerine Vanilla Mint®, Malvatricin®, Periogard® e Solução de Clorexidina 0,12% + Óleos essenciais (produto manipulado, Fleming Farmácia de Manipulação). As ligaduras foram encubadas em suspensão multibacteriana e imersas nos agentes químicos. Após a semeadura e contagem de UFC/mL, os resultados foram avaliados estatisticamente. Não houve diferença significativa na aderência de bactérias ao compararmos as duas marcas (p>0.05) e houve grande eficácia na desinfecção com o uso dos colutórios Periogard® e Listerine Vanilla Mint® (p<0.05). O uso em Ortodontia dos colutórios pode ser útil na prevenção da formação de biofilme dental e uma alternativa para a pré-desinfecção das ligaduras


Deficient oral hygiene favors biofilm formation and outset of gingival inflammation. The use of orthodontic appliances has an important impact on the oral microbiota once it provides additional sites of bacterial adhesion. Chemicals have been employed in order to inhibit the formation of biofilm, bacterial growth, and adhesion of bacteria to surfaces. This study compared the adherence of bacteria on Morelli™ and OrthoSource™ elastic ligatures and potential disinfection by mouthwashes: Plax Ice™, Listerine Vanilla Mint™, Malvatricin™, Periogard™ and chlorhexidine solution 0.12% + essential oils (Fleming Farmácia de Manipulação, Ponta Grossa - PR). Ligatures were incubated in multibacterial suspension and soaked in the chemicals. After platting on agar and obtaining the number of cfu/mL, results were evaluated statistically. No significant difference in bacterial adherence was observed when compared the two brands (p>0.05) and disinfection with the mouthwashes was very effective, mainly with Periogard™ and Listerine Vanilla Mint™ (p<0.05). The use of mouthwashes may be useful in the prevention of biofilm formation in dental braces, as well as an alternative for disinfecting the ligatures prior to installation.


Assuntos
Placa Dentária , Desinfecção
17.
Ortho Sci., Orthod. sci. pract ; 6(24): 480-487, 2013. ilus, tab, graf
Artigo em Português | LILACS, BBO - Odontologia | ID: lil-729335

RESUMO

Este estudo avaliou a Dureza Vickers (HV), a resistência adesiva (RA) e o índice de adesivo remanescente (IAR) de três resinas ortodônticas: Concise (CO), Transbond XT (TB) e a Aqualite (AQ). Para a análise da HV foram confeccionados 30 corpos de prova em matrizes metálicas pré-fabricadas com diâmetro de 0,5 mm e 0,2 mm de espessura. Os valores de HV foram CO = 43,29 ± 1,66, TB = 43,69 ± 1.37 e AQ = 43,51 ± 1,30. Os resultados para HV foram analisados pelo teste ANOVA one-way e pós-teste de Tukey, onde não foram encontradas diferenças estatísticas significativas (p>0,05). Para a RA foram utilizados 60 pré-molares e confeccionados corpos de prova, os quais foram divididos em 3 grupos (n= 20) para a colagem de bráquetes metálicos com as resinas Concise (CO), Transbond XT (TB) e Aqualite (AQ). Os bráquetes após a colagem foram submetidos aos ensaios mecânicos de cisalhamento em máquina de ensaio universal SHIMADZU, com velocidade de carga de 0,5 mm/min. A avaliação dos resultados do cisalhamento foram analisados pelo teste de variância ANOVA, e mostraram RA médias para CO de 18,21 ± 6,21 MPa; para TB de 25,02 ± 9,29 MPa e para AQ de 14,31 ± 8,25 MPa. A ANOVA demonstrou diferença estatística entre AQ/TB e CO/TB (p<0,05) e sem diferença estatística significante entre AQ/CO. Para avaliação do IAR utilizou-se o teste não paramétrico de Kruskal-Wallis, seguido do teste de Dunn, sem diferenças estatísticas significativas (p>0,05). Conclui-se que a resina TB apresentou maior RA em relação à CO e AQ. Não existe diferença entre a HV e o IAR entre as resinas.


This study evaluated Vickers hardness (HV), adhesive resistance and adhesive remnant index (ARI) on three orthodontic resins: Concise (CO), Transbond XT (TB), and Aqualite (AQ). For the HV analysis, 30 specimens were prepared with pre-manufactured matrixes with a 0.5 mm width and 0.2 mm thick. HV values were CO = 43.29 ± 1.66, TB = 43.69 ± 1.37 e AQ = 43.51 ± 1.30. Those values were evaluated by the one-way ANOVA test following Tukey test, and no significant statistical differences (p>0.05) were observed. For the RA evaluation, 60 pre-molar specimens were used, divided in 3 groups (n=20) and the metallic brackets were bonded with Concise (CO), Transbond XT (TB), and Aqualite (AQ). After bonding the brackets were submitted to shear bond strength mechanic trials with a SHIMADZU universal testing machine, with a cross-head speed of 0.5 mm per minute. The results of the shear bond strength were evaluated by the ANOVA and revealed RA means for CO values of 18.21 ± 6.21 MPa; 25.02 ± 9.29 MPa for TB, and 14.31 ± 8.25 MPa for AQ. ANOVA showed statistical differences between AQ/TB and CO/TB (p<0.05) while no statistical differences were observed between AQ/CO. For the ARI evaluation, the Kruskal-Wallis non parametric test was performed following the Dunn’s test, without any statistical significant differences (p>0.05). It was concluded that the TB resin presented higher RA values in relation to CO and AQ. There are no differences between the HV and IAR in the studied resins.


Assuntos
Humanos , Adolescente , Colagem Dentária , Resistência ao Cisalhamento
18.
Ortho Sci., Orthod. sci. pract ; 6(23): 383-389, 2013. ilus, tab
Artigo em Português | LILACS, BBO - Odontologia | ID: lil-707592

RESUMO

O objetivo deste artigo é relatar o tratamento ortodôntico de uma paciente adulta, portadora de Classe II divisão 1ª com o auxílio de miniplacas. A paciente apresentava discrepância maxilomandibular (ANB = 8º), relação de Classe II de caninos e molares de ambos os lados, sobremordida profunda, sobressaliência aumentada e incisivos superiores protruídos. O perfil facial era convexo e o terço inferior levemente aumentado. O plano de tratamento consistiu em alinhamento e nivelamento dos arcos superior e inferior e, posteriormente, realizou-se a instalação das miniplacas que forneceram ancoragem para a distalização do arco superior. O resultado clínico pode ser considerado satisfatório para um tratamento esquelético compensatório.


The aim of this article is to report the orthodontic treatment of an adult patient, carrier of Class II division 1ª with the aid of miniplates. The patient had maxillomandibular discrepancy (ANB = 8), Class II relationship of canines and molars on both sides, deep overbite, increased overjet and, upper incisor protrusion. The facial profile was convex and the lower third slightly increased. The treatment plan consisted of alignment and leveling of the upper and lower arches and later held the installation of miniplates that provided anchorage for distalization of the maxillary arch. The clinical outcome can be considered satisfactory for treatment compensatory skeletal.


Assuntos
Humanos , Feminino , Adulto , Má Oclusão Classe II de Angle , Âncoras de Sutura
19.
Dental press j. orthod. (Impr.) ; 17(2): 69-76, Mar.-Apr. 2012. ilus, graf, tab
Artigo em Inglês | LILACS-Express | LILACS | ID: lil-626371

RESUMO

OBJECTIVE: To compare in vitro shear bond strength (SBS) of different orthodontic adhesives in bonding and repeatedly rebonding metal brackets, and to evaluate the bond failure site with the adhesive remnant index (ARI). METHODS: Specimens consisted of 90 extracted human first premolars, randomly divided into three groups (n=30). The adhesives Alpha Plast (AP), ConciseTM (CO) and TransbondTM XT (TB) were used in each group. Three SBS tests were performed, i.e., one at T0 (initial) and the other two at T1 and T2 (first and second rebondings, respectively), observing a 24-hour interval. The tests were performed in a Shimadzu AG-I (10kN) SBS testing machine, at a speed of 0.5 mm/min. RESULTS: SBS data were subjected to ANOVA, Tukey's test and Bonferroni test (p<0.05). For the ARI, the Kruskal Wallis test was performed, followed by the Dunn test. The results revealed that at T0 groups AP and CO showed SBS values that were near, but above TB values; and at T1 and T2, the highest SBS values were observed for the AP group, followed by the CO and TB groups. CONCLUSION: Statistically significant differences were found in SBS between groups AP, CO and TB during bonding and repeated rebondings of unused metal brackets, with group AP achieving the highest SBS value. Regarding ARI, adhesive AP exhibited bond failure at the enamel-adhesive interface, with a higher enamel fracture frequency.

20.
Ortho Sci., Orthod. sci. pract ; 5(20): 499-504, 2012. ilus, tab, graf
Artigo em Português | LILACS, BBO - Odontologia | ID: lil-729315

RESUMO

Este estudo avaliou a resistência adesiva ao cisalhamento (RAC) e o índice de adesivo remanescente (IAR) na colagem de bráquetes metálicos com as resinas Concise Ortodôntico / 3M e Ortho-One / Bisco. Foram construídos corpos de prova com 60 pré-molares humanos superiores divididos aleatoriamente (n=30) para cada um dos grupos. O procedimento de colagem foi realizado conforme as instruções de cada fabricante. O ensaio de cisalhamento foi realizado com uma máquina MTS 810. Os resultados mostraram uma média de RAC para as resinas Concise e Ortho-One de 29,99±15,89 MPa e de 22,52±12,2 MPa, respectivamente. A análise estatística pelo teste t de Student não mostrou diferença estatística significante quanto à RAC (p>0,05). Para avaliação do IAR, foi utilizado o teste não paramétrico de Kruskal-Wallis, o qual não mostrou diferença estatística significativa quanto ao padrão de descolagem (p=0,361). Conclui-se que não há diferença significativa entre as resinas testadas e ambos os materiais apresentaram padrões aceitáveis para um bom desempenho clínico.


This study assessed the shear bond strength and adhesive remanescent index (ARI) when bonding metallic brackets using the composites Concise Orthodontic Bonding System/3M and Ortho One/Bisco. Sixty human upper premolars were used divided randomly in two groups. Bonding procedure was conducted following each manufacturer’s instructions. The results showed that the mean shear bond strength with Concise and Ortho One ranged between 29,99 ± 15,89 MPa and 22,52 ± 12,2 MPa, respectively. Data were submitted to statistical analysis by the t test of Student (showed no significant statistical differences between the composites) (p>0,05). In evaluation of ARI was utilized Kruskal-Wallis test without difference statistical significance. Both the materials showed acceptable patterns for a good clinical performance.


Assuntos
Humanos , Adolescente , Colagem Dentária , Braquetes Ortodônticos , Resistência ao Cisalhamento
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