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1.
Braz. j. oral sci ; 21: e225263, jan.-dez. 2022. ilus
Article in English | LILACS, BBO | ID: biblio-1369650

ABSTRACT

Aim: This study was fulfilled to evaluate the flexural strength, micro-hardness, and release of two fluoride ions of bioactive restorative materials (Cention N and Activa Bioactive), a resin modified glass ionomer (Fuji II LC), and a resin composite (Filtek z250). Methods: Forty samples from four restorative materials (Activa Bioactive, Fuji II LC, Cention N, and Filtek Z250) were provided according to the current standards of ISO 4049/2000 guide lines. Subsequently, the samples were stored for 24 hours and 6 months in artificial saliva, and successively, flexural strength and micro-hardness of the samples were measured. For each studied groups the pH was decreased from 6.8 to 4 in storage solution. The rate of changes in fluoride ion release was measured after three different storage periods of 24 hours, 48 hours, and 6 months in distilled water, according to the previous studies' method. Two-way ANOVA, One-way ANOVA, Tukey HSD Pair wise comparisons, and independent t-tests were used to analyze data (α= 0.05). Results: The highest flexural strength and surface micro-hardness after 24 hours and also after 6 month were observed for Cention N(p<0.001).Flexural strength of all samples stored for 6 months was significantly lower than the samples stored for 24 hours(p<0.001). The accumulative amount of the released fluoride ion in RMGI, after six-month storage period in distilled water was considerably higher (p<0.001) than 24 hours and 48 hours storage. The amount of fluoride ion release with increasing acidity of the environment (from pH 6.8 to 4) in Fuji II LC glass ionomer was higher than the bioactive materials (p<0.05). Conclusion: The flexural strength of RMGI was increased after storage against the Activa Bioactive,Cention N and Z250 composite. Storage of restorative materials in artificial saliva leads to a significant reduction in micro hardness. The behavior and amount of released fluoride ions in these restorative materials, which are stored in an acidic environment, were dependent on the type of restorative material


Subject(s)
Saliva, Artificial , Materials Testing , Dental Materials , Physical Phenomena
2.
Braz. j. oral sci ; 21: e225334, jan.-dez. 2022. ilus
Article in English | LILACS, BBO | ID: biblio-1384158

ABSTRACT

Aim This study aimed to analyze the influence of finishing and polishing (F/P) protocols on resin surface through roughness (Ra) values and laser scan microscopy observations. Methods Forty-eight (n=48) resin specimens were sorted into four groups (n=12), according to the type of resin used: Filtek Z250 (Z250), Filtek Z350 (Z350), Filtek One Bulk Fill (BF), Filtek P60 (P60). The specimens were sorted into six groups according to the type of F/P system used (n=2/group): Control group, Diamond bur (KG Sorensen), Soflex Pop-On Discs (3M ESPE), Soflex Spiral (3M ESPE), Dura Gloss (American Burs), and Praxis (TDV). Results The highest roughness values (Ra) were attributed to BF group for all F/P systems, except for the Soft-Lex PopOn discs. The Soft-Lex PopOn, Spiral, and Praxis discs presented a better performance for the surface treatment of the tested composite resins. Regardless of the restorative material, the use of diamond bur or single-step abrasive rubber (Dura Gloss) were associated with the highest Ra values. Conclusion The effect of F/P systems on Ra is material-dependent and instrument or system-dependent.


Subject(s)
Microscopy, Confocal , Composite Resins , Dental Materials , Dental Polishing
3.
Braz. j. oral sci ; 21: e227878, jan.-dez. 2022. tab
Article in English | LILACS, BBO | ID: biblio-1384155

ABSTRACT

Aim Assessing the intracoronal bleaching effectiveness of an experimental chlorine dioxide product, based on the walking bleach technique. Methods Extracted bovine incisors were artificially stained with bovine blood and filled with zinc phosphate cement at cementoenamel junction level. Teeth were divided into 3 groups (n=10): (SP) sodium perborate added with distilled water, (CD) chlorine dioxide and (C) control - dry cotton inserted into the pulp chamber. Bleaching agents were used at 0, 7 and 14 days. VITA Easyshadetm (∆Eab) was used to analyze tooth color at the 7th, 14th and 21st days, based on the CIE2000 system. Data were analyzed through ANOVA and Tukey's test. Results There were no statistically significant differences in Δb, ΔE, ΔE00 and ΔWID between CD and the control group. These parameters have shown significant differences between CD and SP, which differed from the control. However, they did not show significant differences either in the control group or in CD at the 7th, 14th and 21st days. Values recorded for SP at the 7th day differed from those recorded at the 14th and 21st days. Δa has shown differences within the same group at the 7th, 14th and 21st days. There was no difference between groups, when they were compared at the same day (7th and 14th). The control group differed from SP at the 21st day. CD did not differ from the other two groups. ΔL did not show differences between groups and times. Conclusion Stabilized chlorine dioxide (0.07%, at pH 3.5) should not be used as intracoronal bleaching agent along with the walking bleach technique.


Subject(s)
Tooth Bleaching , Borates , Chlorine Compounds , Dental Materials , Chlorine Dioxide
4.
Braz. j. oral sci ; 21: e228852, jan.-dez. 2022. ilus
Article in English | LILACS, BBO | ID: biblio-1392917

ABSTRACT

Aim: To evaluate the occlusal and internal marginal adaptation of inlay restorations made of different materials, using CAD-CAM. Methods: Preparations were made for MOD inlays of one-third intercuspal width and 4 mm depth in 30 third human molars. The teeth were restored using CAD-CAM materials (n=10) of nanoceramic resin (Lava Ultimate), polymer-infiltrated ceramic network (VITA ENAMIC), or lithium disilicate glass-ceramic (IPS e.max CAD). The specimens were cemented with dual resin cement and sectioned at the center of the restoration, after which the two halves were evaluated, and photographed The occlusal and internal discrepancy (µm) was determined at five points: cavosurface angle of the occlusal-facial wall (CA-O); center of the facial wall (FW); faciopulpal angle (FPA); center of the pulpal wall (PW); and center of the lingual wall (LW). The data were submitted to the Kruskal-Wallis and the Dunn tests (α=0.05). Results: No difference was observed among the materials regarding the occlusal discrepancy at the CA-O, FPA, or PW internal points. The e.max CAD measurement at FW showed larger internal discrepancy than that of Lava (p=0.02). The internal discrepancy at LW was greater for e.max CAD than VITA ENAMIC (p=0.02). Conclusion: Lithium disilicate glass-ceramic presented greater internal discrepancy in relation to the surrounding walls of the inlay preparations


Subject(s)
Ceramics , Computer-Aided Design , Dental Marginal Adaptation , Dental Materials , Inlays
5.
Braz. j. oral sci ; 21: e226666, jan.-dez. 2022. ilus
Article in English | LILACS, BBO | ID: biblio-1393341

ABSTRACT

Aim: This study analyzed public procurements for different endodontic materials used in the Brazilian public health system and evaluated the variables related to their cost. Methods: A time-series study was performed by screening materials for endodontic application in the public Brazilian Databank of Healthcare Prices from 2010 to 2019. Data were categorized according to material composition and clinical application. The collated variables were used in a multiple linear regression model to predict the impact of unit price in procurement processes. Results: A total of 5,973 procurement processes (1,524,693 items) were evaluated. Calcium hydroxides were found in 79% of the observations (4,669 processes). Prices drop each year by US$1.87 while MTAs and epoxy resins are increasingly purchased at higher prices (US$50.87; US$67.69, respectively). The microregion, the procurement modality, and the type of institution had no influence on unit prices in the adjusted model (p > 0.05). Conclusions: Calcium hydroxide-based materials were the cheapest and most frequently purchased endodontic materials in the public health care system. Novel formulations are being implemented into clinical practice over time and their cost may be a barrier to the broad application of materials such as MTAs, despite their effectiveness


Subject(s)
Biomedical and Dental Materials , Public Health Dentistry , Costs and Cost Analysis , Endodontics , Translational Science, Biomedical , Public Expenditures
6.
Braz. dent. j ; 33(3): 38-46, July-Sept. 2022. tab, graf
Article in English | LILACS-Express | LILACS, BBO | ID: biblio-1384033

ABSTRACT

Abstract This study evaluated the Reciproc R25 and Pro-R 25 instruments in unused condition, after one and a second use in endodontic retreatment employing a noncontact 3D light interferometer profiler, scanning electron microscopy (SEM) and cyclic fatigue tests. Twenty single-root teeth were instrumented with Reciproc R25 and filled with gutta-percha and sealer. A 3D profiler with a 20x objective using the Mx™ software was used to evaluate the cutting blade surfaces of Reciproc R25 and Pro-R 25 (n=5 per group) in unused condition, after the first and second uses in retreatment procedures. After retreatment, SEM was used to evaluate the topographic features of the used instruments. Cyclic fatigue tests were performed to compare new to used instruments. One-way ANOVA followed by Tukey test was used to compare the tested instruments before and after the first and second uses. Student t-test was used to compare the different instruments and for cyclic fatigue evaluation. No significant differences were observed in the cutting blade surfaces of Reciproc and Pro-R before and after one and two uses (p>0.05). Reciproc without use showed higher Sa and Sq when compared to Pro-R without use (p<0.05). No differences were observed between Reciproc and Pro-R after one and two uses (p>0.05). New and unused Reciproc showed longer time to fracture than Pro-R instruments (p<0.05), and only Pro-R showed differences between new and used instruments (p<0.05). Retreatment procedures with Reciproc and Pro-R did not change the surface topography of instruments. Reciproc had greater resistance to cyclic fatigue compared with Pro-R.


Resumo Este estudo avaliou os instrumentos Reciproc R25 e Pro-R 25 sem uso, após um primeiro e um segundo uso em retratamento endodôntico com perfilômetro 3D por interferometria de luz sem contato, microscópio eletrônico de varredura (MEV) e testes de fadiga cíclica. Vinte dentes unirradiculares foram instrumentados com Reciproc R25 e obturados com guta-percha e cimento endodôntico. Um perfilômetro 3D com uma objetiva 20x usando o software Mx ™ foi usado para avaliar as superfícies da lâmina de corte do Reciproc e Pro-R (n = 5 por grupo) na condição sem uso, após o primeiro e após um segundo uso em procedimentos de retratamento. Após retratamento, o MEV foi usado para avaliar as características topográficas dos instrumentos utilizados. Testes de fadiga cíclica foram realizados para comparar instrumentos novos com instrumentos usados. O teste One-way ANOVA seguido pelo teste de Tukey foi usado para comparar os instrumentos testados nos diferentes estágios. Para comparar os diferentes instrumentos e para avaliação de fadiga cílcica, foi utilizado o Student t-test. Não foram observadas diferenças estatisticamente significantes nas superfícies das lâminas de corte dos instrumentos Reciproc e Pro-R antes e após um e dois usos (p> 0,05). O Reciproc na condição sem uso apresentou maior Sa e Sq quando comparado ao Pro-R (p <0,05). Não foram observadas diferenças entre Reciproc e Pro-R após um e dois usos (p> 0,05). O Reciproc sem uso apresentou maior tempo de fratura do que os instrumentos Pro-R (p<0,05), e apenas o Pro-R apresentou diferenças entre instrumentos novos e usados (p<0,05). Os procedimentos de retratamento com Reciproc e Pro-R não alteraram a topografia da superfície dos instrumentos. Reciproc apresentou maior resistência à fadiga cíclica em comparação com o Pro-R.

7.
Odovtos (En línea) ; 24(2)ago. 2022.
Article in English | LILACS-Express | LILACS, SaludCR | ID: biblio-1386603

ABSTRACT

Abstract The aim of this in vitro study is to investigate the effects of acidic beverages on the discoloration of bulk-fill composites with different viscosities. 144 disc-shaped specimens (8mm diameter × 2mm thick) were prepared from four different composite resins including a nanohybrid (Filtek Ultimate), two packable bulk- fill (Filtek Bulk Fill, Tetric N Ceram Bulk Fill), and a flowable bulk-fill composite (Tetric N Flow Bulk Fill). The specimens of each group were divided into 3 subgroups and submerged in distilled water, orange juice and coke (n=12). Color difference (ΔE) were measured using CIELab color space and a compact spectrophotometer (VITA Easyshade) at baseline and after 30 days of immersion. Data were analyzed using two- way ANOVA and Tukeys HSD post-hoc tests (P2.7) was observed for all bulk-fill composites tested. It can be speculated that orange juice has a more negative effect on the color stability compared to coke. Additionally, flowable bulk-fill composite was more prone to discoloration than condensable bulk-fill composites.


Resumen El objetivo de este estudio fue investigar los efectos de las bebidas ácidas en la decoloración de resinas compuestas tipo Bulk con diferentes viscosidades. Se prepararon 144 muestras en forma de disco (8mm de diámetro x 2mm de grosor) a partir de cuatro resinas compuestas diferentes que incluyen un nanohíbrido (Filtek Ultimate), dos de pasta condensables tipo Bulk (Filtek Bulk Fill, Tetric N Ceram Bulk Fill) y una fluida (Tetric N Flow Bulk Fill). Las muestras de cada grupo se dividieron en 3 subgrupos y se sumergieron en agua destilada, jugo de naranja y Coca-Cola (n=12). La diferencia de color (ΔE) se midió utilizando el CIELab y un espectrofotómetro compacto (VITA Easyshade) al inicio y después de 30 días de inmersión. Los datos se analizaron mediante ANOVA bidireccional y pruebas post-hoc HSD de Tukey (P2,7) para todos los materiales resinosos. Se puede especular que el jugo de naranja tiene un efecto más negativo sobre la estabilidad del color en comparación con la Coca-Cola. Además, la resina fluida fue más propensa a la decoloración que las resinas condensables.


Subject(s)
Tooth Discoloration , Composite Resins , Food Coloring Agents
8.
Odovtos (En línea) ; 24(2)ago. 2022.
Article in English | LILACS-Express | LILACS, SaludCR | ID: biblio-1386584

ABSTRACT

Abstract The aim was to determine the prevalence and types of the allergies present among dental professionals in Costa Rica. We performed a cross-sectional study on 664 dentists who completed a self-reported questionnaire. A descriptive cross-sectional study with inferential analysis was carried out. Dentists reported allergies prior to studying dentistry in 39% of cases, 36% reported chronic illnesses, and 61% of the dentists reported first-degree relatives with some type of allergic reaction. Different allergies had a similar prevalence among the dental professionals (ranging between 19%-26%), all allergic manifestations occurred within the first 120 minutes after exposure. The average time of exposure to dentistry-related environments was 16 years (95% CI) among all the dentists surveyed. There is a positive correlation between the presence of a chronic illness and the predisposition to develop allergic reactions among dentists. In addition, there is a directly proportional relationship between age, time of exposure to dental environments, and the risk of developing allergic conditions to dental materials. The main adverse reactions reported due to exposure to dental materials, medicines and/or food were gastrointestinal, skin, and respiratory problems.


Resumen El objetivo del estudio fue determinar la prevalencia y tipo de alergias presentes entre los odontólogos en Costa Rica. Se realizó un estudio transversal descriptivo en 664 dentistas que completaron un cuestionario, utilizando análisis inferencial para el procesamiento de los resultados. Los odontólogos reportaron alergias previo a estudiar odontología en un 39% de los casos, el 36% informó enfermedades crónicas y el 61% de los dentistas mencionó tener familiares en primer grado que habían presentado algún tipo de reacción alérgica. Diferentes tipos de alergias tuvieron una prevalencia similar entre los odontólogos (oscilando entre el 19% y el 26%), todas las manifestaciones alérgicas ocurrieron dentro de los primeros 120 minutos después de la exposición al alergeno. El tiempo medio de exposición a entornos relacionados con la odontología fue de 16 años (IC del 95%) entre todos los dentistas encuestados. Existe una correlación positiva entre la presencia de una enfermedad crónica y la predisposición a desarrollar reacciones alérgicas entre los dentistas. Además, existe una relación directamente proporcional entre edad, tiempo de exposición a entornos dentales, y el riesgo de desarrollar reacciones alérgicas a los materiales dentales. Las principales reacciones adversas notificadas posterior a la exposición a materiales dentales, medicamentos y/o alimentos fueron problemas gastrointestinales, cutáneos y respiratorios.


Subject(s)
Humans , Dental Materials , Dentistry , Hypersensitivity , Occupational Health , Costa Rica
9.
Odovtos (En línea) ; 24(1)abr. 2022.
Article in English | LILACS-Express | LILACS, SaludCR | ID: biblio-1386569

ABSTRACT

Abstract Immediate loading of full-arch prostheses on dental implants in the upper arch is challenging, as the bone is of low quality and obtaining sufficient torque may be difficult. The purpose of this case report is to describe the rehabilitation of a full- arch by means of placement of four internal tapered connection tilted implants and immediate loading. A 65-year-old man sought dental care with a partially edentulous upper arch. The teeth presented mobility and were extracted. In a second step, two conventional-length implants were placed in the anterior region and two tilted and nasal wall-directed extra-long implants in the posterior region. The insertion torques of 60 N.cm allowed the installation of an immediate prosthesis (hybrid). The clinical case report suggests that the placement of tilted and extra-long implants in the paranasal bone and immediate loading may be a viable option for rehabilitation of the edentulous upper arch.


Resumen La carga inmediata de prótesis de arco completo en implantes dentales en el arco superior es un desafío, ya que el hueso es de baja calidad y puede ser difícil obtener un par suficiente. El propósito de este reporte de un caso es describir la rehabilitación de un arco completo mediante la colocación de cuatro implantes inclinados de conexión cónica interna y carga inmediata. Un hombre de 65 años buscó atención dental con un arco superior parcial sin dientes. Los dientes presentaron movilidad y fueron extraídos. En un segundo paso, se colocaron dos implantes de longitud convencional en la región anterior y dos implantes extralargos inclinados y dirigidos a la pared nasal en la región posterior. Los pares de inserción de 60 N.cm permitieron la instalación de una prótesis inmediata (híbrida). El informe del caso clínico sugiere que la colocación de implantes inclinados y extralargos en el hueso paranasal y la carga inmediata pueden ser una opción viable para la rehabilitación del arco superior desdentado.


Subject(s)
Humans , Male , Aged , Dental Implants , Suture Anchors
10.
Odovtos (En línea) ; 24(1)abr. 2022.
Article in English | LILACS-Express | LILACS, SaludCR | ID: biblio-1386568

ABSTRACT

Abstract Cetrimide (CTR) is a cationic surfactant detergent with antimicrobial and antibiofilm activity. The aim of this study was to evaluate setting time, pH, solubility and antibiofilm activity of tricalcium silicate cement (TSC) with zirconium oxide (ZrO2) and its association with 0.2 and 0.4% cetrimide. Initial and final setting times (IST and FST) were assessed based on ISO-6876. pH was evaluated at periods of 1,3,7,14 and 21 days. Solubility was analyzed by weight loss. A modified direct contact test (MDCT) on the biofilm of Enterococcus faecalis formed on bovine root dentin blocks was performed, after 6 hours of manipulation and 15 hours of contact time. The analysis was performed by UFC mL ¯¹ counting. The data were analyzed by ANOVA and Tukey's tests (α=0.05). Higher IST was observed for TSC/ZrO2+CTR in both concentrations than for TSC/ZrO2 and lower FST for TSC/ZrO2+0.4% CTR (p0.05). All materials exhibited increased mass. TSC/ZrO2+CTR 0.4% had lower mass gain than the other materials (p<0.05). The highest antibiofilm activity was observed for TSC/ZrO2+CTR in both concentrations, when compared with the positive control (p<0.05). In conclusion, CTR exhibited potential to promote greater antibiofilm activity to tricalcium silicate cement, without harming its physicochemical properties of setting time, pH and solubility.


Resumen Cetrimida (CTR) es un detergente y surfactante catiónico con actividad antimicrobiana y antibiofilm. El objetivo de este estudio fue evaluar el tiempo de fraguado, pH, solubilidad y actividad antibiofilm del cemento de silicato tricálcico (CST) con óxido de zirconio (ZrO2) y su asociación con CTR a 0.2% y 0.4%. Tiempo de fraguado inicial y final (TFI y TFF) fueron determinados con base en las normas ISO-6876. pH fue evaluado en los períodos de 1,3, 7,14 y 21 días. Solubilidad fue analizada por la pérdida de masa/peso. El test de contacto directo modificado (TCDM) fue realizado sobre biofilm de Enterococcus faecalis formado en dentina radicular bovina, después de 6 horas de manipulación de los cementos y 15 horas de contacto. El análisis fue realizado por la cuantificación de UFC mL¯¹. Los datos fueron analizados usando las pruebas de ANOVA y Tukey (α=0.05). Mayor TFI fue observado para CST/ ZrO2+CTR en las dos concentraciones que para TSC/ZrO2 y menor TFF para TSC/ ZrO2+CTR 0.4% (p0.05). Todos los materiales mostraron aumento de masa. TSC/ZrO2+CTR 0.4% tuvo menor gano de masa que los otros materiales (p<0.05). Mayor actividad antibiofilm fue observado para CST/ZrO2+CTR en las dos concentraciones, cuando comparados con el grupo control positivo (p<0.05). En conclusión, CTR demostró potencial para promover superior actividad antibiofilm al cemento de silicato tricálcico (CST), sin perjudicar sus propiedades físico-químicas de tiempo de fraguado, pH y solubilidad.


Subject(s)
Silicate Cement/analysis , Dental Plaque , Cetrimonium/analysis
11.
Article in English | LILACS-Express | LILACS | ID: biblio-1385868

ABSTRACT

ABSTRACT: The most common failure in implantology are due to mechanical instability. Torque loosening or fracture of the screws are the most frequent complications. Furthermore, the fractured screw retrieval is complicated and time-consuming. So, modifications in the design of implant systems are justifiable to offer a greater degree of biomechanical stability. Thus, the present study proposes to evaluate an experimental geometry for abutment screw regarding failure probability and torque loss. Twenty implant/abutments sets (e-fix, A.S. Technology - Titanium Fix) were divided into the following groups (n=10 in each group): (1) Conventional screw (Screw neck ø 1.5 mm) and (2) Experimental screw (screw neck constricted ø 1.2 mm). The abutments were tightened with a controlled torque meter device following the manufacturer's recommendations. Mechanical cycling was carried out with a load of 50 N.cm during 5 x 10 6 cycles with a frequency of 2 Hz at a temperature of 37°C (ISO 14801). A digital torque meter was used to measure the reverse torque values of the prosthetic screw and the micro abutment screw, before and after loading. Data were statistically analyzed by One-way Anova and Tukey test (95 %). The results of the mean values of torque loss of the micro abutment screw were 58.44 % for the control group and 55.31 % for the experimental group and the mean torque loss for the prosthetic screw was 53.3 % and 61.3 % of the conventional and experimental groups, respectively. The survival probability was 100 % for both screw groups. It was concluded that experimental screw showed a similar behavior to conventional screws, showing similar reliability after fatigue life testing.


RESUMEN: En implantología las fallas más habituales se deben a la inestabilidad mecánica. El aflojamiento del torque o la fractura de los tornillos son las complicaciones más frecuentes. Además, la recuperación del tornillo fracturado es complicada y requiere mucho tiempo. Por tanto, las modificaciones en el diseño de los sistemas de implantes están justificados para ofrecer un mayor grado de estabilidad biomecánica. Por lo tanto, el presente estudio propone evaluar una geometría experimental para tornillo de pilar en cuanto a probabilidad de falla y pérdida de torque. Se dividieron veinte conjuntos de implantes / pilares (e-fix, AS Technology - Titanium Fix) en los siguientes grupos (n = 10 en cada grupo): (1) Tornillo convencional (cuello de tornillo ø 1,5 mm) y (2) Tornillo experimental (cuello de rosca estrechado ø 1,2 mm). Los pilares se apretaron con un dispositivo medidor de torque controlado siguiendo las recomendaciones del fabricante. El ciclo mecánico se realizó con una carga de 50 N.cm durante 5 x 10 6 ciclos con una frecuencia de 2 Hz a una temperatura de 37° C (ISO 14801). Se utilizó un medidor de torque digital para medir los valores de torque inverso del tornillo protésico y el tornillo de micro pilar, antes y después de la carga. Los datos se analizaron estadísticamente mediante la prueba One-way Anova y Tukey (95%). Los resultados de los valores medios de pérdida de torque del micro tornillo de pilar fueron 58,44 % para el grupo de control y 55,31 % para el grupo experimental y la pérdida de torque media para el tornillo protésico fue 53,3 % y 61,3 % de los grupos convencional y experimental, respectivamente. La probabilidad de supervivencia fue del 100 % para ambos grupos de tornillos. Se concluyó que el tornillo experimental mostró un comportamiento similar a los tornillos convencionales, mostrando una fiabilidad similar después de la prueba de vida a fatiga.

12.
Braz. dent. sci ; 25(4): 1-7, 2022. tab
Article in English | LILACS, BBO | ID: biblio-1397461

ABSTRACT

Objective: The rough surfaces of removable appliances used in pediatric dentistry or orthodontics, may result in an environment for biofilm accumulation, yielding to enamel demineralization. This study aimed to assess the effects of adding nanoparticles of bioactive glass to polymethylmethacrylate to promote the antibacterial activity in acrylic resins. Material and Methods: Acrylic resin specimens (20x20x1mm3) were prepared by adding 2% or 5% bioactive glass. The specimens in the control group without bioactive glass were prepared from the mixture of acrylic powder containing nanoparticles and liquid monomer (n=10 per group). The antibacterial activity of the specimens against Streptococcus mutans and Lactobacillus acidophilus activity in biofilm was investigated through counting colony forming units (CFU). Data were analyzed using a one-way analysis of variance and Tukey's post hoc tests at the significance level of 0.05. Results: The incorporation of 2% (p=0.001) and 5% (p<0.001) bioactive glass in acrylic resin reduced the metabolic activity and CFU of L. acidophilus. For S.mutans, antimicrobial activity was observed only with the 5% concentration of bioactive glass, and this group was statistically different from the control (p<0.001). When L. acidophilus was exposed to polymethyl methacrylate with 5% bioactive glass, significant decrease was observed compared to the control group (p<0.05). Conclusion: Adding bioactive glass nanoparticles into the acrylic resins used for fabricating removable appliances revealed a greater antibacterial effect against cariogenic bacteria tested (AU)


Objetivo: As superfícies rugosas dos aparelhos removíveis utilizados em Odontopediatria ou Ortodontia, podem resultar em um ambiente para acúmulo de biofilme, cedendo à desmineralização do esmalte. Este estudo teve como objetivo avaliar os efeitos da adição de nanopartículas de vidro bioativo ao polimetilmetacrilato para promover a atividade antibacteriana em resinas acrílicas. Material e Métodos: Amostras de resina acrílica (20x20x1 mm3) foram preparadas pela adição de 2% ou 5% de vidro bioativo. Os corpos de prova do grupo controle sem vidro bioativo foram preparados a partir da mistura de pó acrílico contendo nanopartículas e monômero líquido (n=10 por grupo). A atividade antibacteriana dos espécimes sobre a atividade de Streptococcus mutans e Lactobacillus acidophilus em biofilme foi investigada através da contagem de unidades formadoras de colônias (UFC). Os dados foram analisados por meio de análise de variância unidirecional e testes post hoc de Tukey com nível de significância de 0,05. Resultados: A incorporação de 2% (p=0,001) e 5% (p<0,001) de vidro bioativo em resina acrílica reduziu a atividade metabólica e UFC de L. acidophilus. Para S. mutans, a atividade antimicrobiana foi observada apenas com a concentração de 5% de vidro bioativo, sendo este grupo estatisticamente diferente do controle (p<0,001). Quando L. acidophilus foi exposto ao polimetilmetacrilato com 5% de vidro bioativo, foi observada diminuição significativa em relação ao grupo controle (p<0,05). Conclusão: A adição de nanopartículas de vidro bioativo nas resinas acrílicas utilizadas na fabricação de aparelhos removíveis revelou um maior efeito antibacteriano contra as bactérias cariogênicas testadas(AU)


Subject(s)
Acrylic Resins , Dental Materials , Dentists , Anti-Bacterial Agents
13.
Dental press j. orthod. (Impr.) ; 27(3): e222116, 2022. tab, graf
Article in English | LILACS-Express | LILACS, BBO | ID: biblio-1384695

ABSTRACT

ABSTRACT Objective: This study aimed to investigate the antimicrobial activity and shear bond strength (SBS) of orthodontic brackets to bovine enamel using experimental composites with different concentrations of silicon dioxide-coated silver nanoparticles (Ag@SiO2 NPs). Methods: Fifty bovine incisors were divided into five groups according to the composite (n = 10): G1 - Control Group (Transbond XT Resin), G2 - Experimental composite without Ag@SiO2 NPs; G3 - Experimental composite with 0.5% of Ag@SiO2 NPs; G4 - Experimental composite with 1% of Ag@SiO2 NPs; G5 - Experimental composite with 3% of Ag@SiO2 NPs. The SBS test was performed using a universal mechanical testing machine, and the adhesive remnant index (ARI) was analyzed by optical microscopy. For the antimicrobial activity evaluation, Streptococcus mutans (S. mutans) biofilm was formed for three days in hydroxyapatite discs. Posteriorly, S. mutans colony forming units (CFU) were evaluated. For SBS analysis, Analysis of Variance was used, followed by the Tukey test, at a 5% statistical significance level. The CFU data were analyzed by Kruskal-Wallis, followed by Dunn as a post-hoc test. The ARI results were analyzed descriptively. Results: There was no statistically significant difference in SBS values between the experimental and control groups (p>0.05). A 3% incorporation of Ag@SiO2 NPs statistically reduced the SBS values (p<0.05) compared to the 1% group. The addition of 3% of Ag@SiO2 NPs to the composites significantly reduced S. mutans biofilm formation, compared to group G2 (p<0.05). Conclusion: Composites incorporating 3% of Ag@SiO2 NPs presented similar SBS values compared to the control group, and showed significant antimicrobial activity.


RESUMO Objetivo: O presente estudo objetivou investigar a atividade antimicrobiana e a resistência de união ao cisalhamento (RU) de braquetes ortodônticos colados em esmalte bovino, utilizando compósitos experimentais com diferentes concentrações de nanopartículas de prata revestidas com dióxido de silício (NPs Ag@SiO2). Material e Métodos: Cinquenta incisivos bovinos foram divididos em cinco grupos, de acordo com o compósito utilizado (n = 10): G1 - Grupo Controle (Resina Transbond XT); G2 - Compósito Experimental sem NPs Ag@SiO2; G3 - Compósito Experimental com 0,5% de NPs Ag@SiO2; G4 - Composto Experimental com 1% de NPs Ag@SiO2; e G5 - Compósito Experimental com 3% de NPs Ag@SiO2. O teste de RU foi realizado em máquina universal de ensaios mecânicos, e o índice de adesivo remanescente (IAR) foi analisado por microscopia óptica. Para a avaliação da atividade antimicrobiana, biofilme de S. mutans foi formado por três dias em discos de hidroxiapatita. Posteriormente, foram avaliadas as unidades formadoras de colônias (UFC) de S. mutans. Para a análise de RU, foi utilizada a Análise de Variância, seguida do teste de Tukey, com nível de significância estatística de 5%. Os dados de UFC foram analisados por meio do teste de Kruskal-Wallis, seguido do teste post-hoc de Dunn. Os resultados de IAR foram analisados descritivamente. Resultados: Não houve diferença estatisticamente significativa nos valores de RU entre os grupos experimentais e o grupo controle (p> 0,05). A incorporação de 3% de NPs Ag@SiO2 reduziu estatisticamente os valores de RU (p< 0,05), em comparação ao grupo com 1%. A adição de 3% de NPs Ag@SiO2 ao compósito reduziu significativamente a formação de biofilme de S. mutans, em relação ao grupo G2 (p< 0,05). Conclusão: Os compósitos com incorporação de 3% de NPs Ag@SiO2 apresentaram valores de RU semelhantes ao grupo controle e demonstraram significativa atividade antimicrobiana.

14.
São José dos Campos; s.n; 2022. 59 p. tab, ilus, graf.
Thesis in Portuguese | LILACS, BBO | ID: biblio-1369214

ABSTRACT

Objetivo: Avaliar o comportamento biomecânico do pilar protético Link Universal (TiBase) com diferentes alturas em restaurações implanto-suportadas. Materiais e Métodos: foram utilizados 40 implantes cone morse Titaniumfix Profile (4 x 10 mm) em titânio, divididos em dois grupos (n=20): Link Universal curto (Short) e Link Universal longo (Long). Vinte implantes receberam o pilar protético Link Universal de 4,5 x 4 mm (Short) e vinte implantes receberam o pilar protético Link Universal de 4,5 x 5,5 mm (Long). Por meio da tecnologia CAD/CAM foram usinadas as coroas em zircônia, cimentadas sobre os pilares protéticos. No ensaio de carga máxima para fratura, o grupo Longo apresentou média de 41,1 ± 6,96 kgf, enquanto a média do grupo curto foi de 49,5 ± 7,68, sem diferença estatística entre eles. Os espécimes passaram pelo teste de sobrevivência em fadiga (2.000.000 ciclos na frequência de 2 Hz com aplicador de aço inoxidável de 1,6 mm de diâmetro), conforme parâmetros descritos na ISO 14801:2007 e não apresentaram falhas. Na sequência, foram submetidos ao teste de sobrevivência stepwise, os espécimes não apresentaram diferenças em relação ao número de ciclos para falha, porém, em relação à carga aplicada, o pilar Link Universal Longo mostrou-se mais resistente que o pilar Link Universal Curto. A análise por elementos finitos foi realizada com os parâmetros obtidos no teste stepwise, com aplicação de carga de 450 N em 30º, simulando a condição do teste de fadiga. Os desenhos foram montados com o software Rhinoceros (version 5.4.2 SR8, McNeel Noth America, Seattle, WA, EUA) e processados no software Ansys (version 19.2, ANSYS Inc., Houston, TX, USA). O comportamento biomecânico do conjunto composto por implante, pilar protético, parafuso passante e coroa monolítica foi semelhante entre os grupos. Concluiu-se que ambas alturas da área de cimentação do pilar Link Universal apresentaram comportamento à fadiga favorável à sobrevivência clínica. (AU)


Objective: Evaluate the biomechanical behavior of the Universal Link (Ti-Base) prosthetic abutment with different heights in implant-supported restorations. Materials and Methods: 40 Titaniumfix Profile implants (4 x 10 mm) in titanium were used, divided into two groups (n=20): Short Universal Link (Short) and Long Universal Link (Long). Twenty implants received the 4.5 x 4 mm Link Universal Prosthetic Abutment (Short) and twenty implants received the 4.5 x 5.5 mm Link Universal Prosthetic Abutment (Long). Using CAD/CAM technology, the zirconia crowns were machined and cemented on the prosthetic abutments. In the maximum fracture load test, the Long group presented an average of 41.1 ± 6.96 kgf, while the average of the short group was 49.5 ± 7.68, with no statistical difference between them. The specimens passed the fatigue survival test (2,000,000 cycles at a frequency of 2 Hz with a stainless steel applicator with a diameter of 1.6 mm), according to the parameters described in ISO 14801:2007 and showed no failures. Subsequently, they were submitted to the stepwise survival test, the specimens did not show differences in relation to the number of cycles to failure, however, in relation to the applied load, the Long Universal Link abutment was more resistant than the Short Universal Link abutment. The finite element analysis was performed with the parameters obtained in the stepwise test, with a load of 450 N at 30º, simulating the condition of the fatigue test. The drawings were assembled with Rhinoceros software (version 5.4.2 SR8, McNeel Noth America, Seattle, WA, USA) and processed in Ansys software (version 19.2, ANSYS Inc., Houston, TX, USA). The biomechanical behavior of the set consisting of implant, prosthetic abutment, through screw and monolithic crown was similar between the groups. It was concluded that the Link Universal abutment presented fatigue behavior favorable to clinical survival independently of it's height (AU)


Subject(s)
Dental Implants , Cementation , Crowns , Dental Materials , Inlays
15.
Braz. oral res. (Online) ; 36: e069, 2022. tab, graf
Article in English | LILACS-Express | LILACS, BBO | ID: biblio-1374746

ABSTRACT

Abstract: This study aimed to compare the physicochemical properties of MTA Angelus (MTA-A), MTA Repair HP (MTA-HP), and Biodentine (BD). Setting times (n = 7) were determined in accordance with ASTM C266-15. Solubility (n = 11), pH (n = 10), and calcium ion release (n = 10) were evaluated up to 28 days in accordance with ANSI/ADA specification no. 57. Radiopacity was assessed by ANSI/ADA (n = 10) and the tissue simulator method (n = 10). In both methods, the specimens were radiographed using an aluminum stepwedge and the digital radiographs were analyzed in Adobe Photoshop, determining the mean grayscale pixel values of the materials, of the 3-mm aluminum stepwedge, and of the dentin, the latter of which was analyzed on the tissue simulator. The data obtained from each test were statistically analyzed and compared (p < 0.05). MTA-A presented longer final setting time compared with the other materials. There were no significant differences in the mass values of materials during the experiment. All materials presented an alkaline pH. BD promoted greater calcium ion release in most of the experimental periods. All materials presented appropriate radiopacity. BD showed lower radiopacity than MTA-A in the tissue simulator method. All groups presented higher radiopacity in the tissue simulator when compared with the ANSI/ADA method. MTA-A, MTA-HP, and BD showed appropriate physicochemical properties and radiopacity, and were considered suitable to be used in clinical practice.

16.
Braz. oral res. (Online) ; 36: e037, 2022. tab, graf
Article in English | LILACS-Express | LILACS, BBO | ID: biblio-1364588

ABSTRACT

Abstract: This paper evaluates the physicochemical and biological properties of experimental resin-based dual-cured calcium aluminate (CA) and calcium titanate (CTi) materials for vital pulp therapy (VPT). The experimental dual-cured materials were obtained as two pastes: a) Bis-EMA 10, PEG 400, DHEPT, EDAB, camphorquinone, and butylated hydroxytoluene; and b) fluoride ytterbium, Bis-EMA 10, Bis-EMA 30, benzoyl peroxide, and butylated hydroxytoluene. The materials were divided into six groups based on the added calcium component: MTA (MTA®, Angelus); CLQ (Clinker-Fillapex®, Angelus); CA (calcined at ,1200°C in pastes a and b); CA800 (calcined at 800°C in paste a); CA1200 (calcined at 1,200°C in paste a); and CTi (paste a). The real-time degree of conversion and rate of polymerization (n = 3), diametral tensile strength (n = 10), hydrogen potential (n = 15), calcium ion release (n = 10), water sorption and solubility (n = 10), and cell viability (n = 6) were evaluated. One- and two-way ANOVA and Tukey's post hoc test were used in the analysis of the parametric data, and Kruskal-Wallis and Dunn's multiple tests were used to analyze the nonparametric data (α = 0.05). CLQ, CA800 and CA1200 had the highest diametral tensile strength. The water solubility of MTA was similar to that of CA800, CA1200 and CTi. CA800 and CA1200 resulted in cell viabilities similar to those of MTA and CLQ. The experimental dual-cured CA-based material that calcined at 800°C showed physicochemical and biological properties suitable for VPT, and similar to those of MTA.

17.
Pesqui. bras. odontopediatria clín. integr ; 22: e210058, 2022. tab, graf
Article in English | LILACS, BBO | ID: biblio-1365226

ABSTRACT

ABSTRACT Objective To evaluate and compare the effect of 17% Ethylenediaminetetraacetic Acid (EDTA), 9% Etidronic acid (HEDP), and 7% Maleic acid (MA) on the push-out bond strength of NeoMTA Plus sealer to the coronal, middle, and apical thirds of root canal dentin. Material and Methods Forty single-rooted human maxillary central incisors were selected and decoronated to 12 mm long root fragments. Working length was established and root canals were then enlarged up to rotary Protaper F3. After each instrumentation, the root canal was irrigated with 2.5% NaOCl. For the final irrigation regimen, the specimens were divided into 4 groups (n=10) and treated with EDTA, HEDP, MA or Saline. Root canals were coated with NeoMTA Plus sealer, and obturation was done with single cone obturation technique. Subsequently, three horizontal sections were taken from the coronal, middle and apical thirds of each specimen, and POBS was measured using a universal testing machine. The type of bond failures was assessed under a stereomicroscope. Statistical analysis was done with One-way ANOVA with Tukey's Post hoc analysis. Results MA and EDTA showed the highest POBS. There was no significant difference in bond strength between MA and EDTA (p>0.05). HEDP and Saline showed lower POBS. Among all the four groups, the coronal third showed the highest values, followed by middle and apical thirds. Conclusion The type of chelating agent used during the root canal treatment significantly affects the bond strength of NeoMTA Plus to the root canal dentin.


Subject(s)
Humans , Root Canal Filling Materials , Tensile Strength , Chelating Agents/chemistry , Dental Cements , Endodontics , Analysis of Variance , Edetic Acid , Etidronic Acid , Dental Materials/chemistry , Incisor , India , Maleic Hydrazide
18.
Rev. Odontol. Araçatuba (Impr.) ; 42(3): 39-44, set.-dez. 2021. ilus
Article in Portuguese | LILACS, BBO | ID: biblio-1291668

ABSTRACT

O objetivo do presente estudo in vitro foi avaliar, por meio de radiografia digital, a qualidade de preenchimento dos canais de dentes incisivos bovinos permanentes jovens quando realizado tampão apical com hidróxido de cálcio e MTA associados a outros materiais e posteriormente obturados. Foram utilizados dentes incisivos permanentes bovinos com rizogênese incompleta preparados de forma manual com as limas tipo K, irrigados com hipoclorito de sódio 1% e soro fisiológico. Após, foram utilizados os materiais indicados para confecção do tampão apical: hidróxido de cálcio P.A associado ao propilenoglicol e ao iodofórmio; hidróxido de cálcio P.A juntamente com MTA e propilenoglicol e somente MTA, em seguida obturados com cones de guta percha e cimento AH Plus e radiografados para avaliação. Os dados foram submetidos ao teste Qui-Quadrado de Pearson e Teste exato de Fisher com nível de significância de 5%. Os resultados obtidos não apresentaram diferença estatisticamente significativa entre os três grupos, sendo que o valor resultado foi de p=0,442, porém o grupo composto pelo cimento de hidróxido de cálcio P.A associado ao MTA e propilenoglicol apresentou uma qualidade de preenchimento boa (100 %) em relação aos outros cimentos avaliados, que se mostraram satisfatório (40%) e bom (60%) no procedimento de apicificação. Não houve diferença significativa de qualidade de preenchimento de tampão apical nos grupos, no entanto o grupo composto pelo hidróxido de cálcio P.A. associado ao MTA e propilenoglicol apresentou resultado superior(AU)


The objective of the present in vitro study was to evaluate, through digital radiography, the quality of filling in the young permanent bovine incisor teeth canals when the apical buffer was performed with calcium hydroxide and MTA associated with other materials and subsequently filled. Permanent bovine incisor teeth with incomplete rhizogenesis were prepared manually with K files type, irrigated with 1% sodium hypochlorite and saline. Afterwards, the materials indicated for making the apical buffer were used: calcium hydroxide P.A associated with propylene glycol and iodoform; calcium hydroxide P.A together with MTA and propylene glycol and only MTA, then filled with gutta-percha cones and AH Plus cement and radiographed for evaluation. The data were submitted to the Pearson's Chi-square test and Fisher's exact test with a significance level of 5%, once the result value was p=0,442. The results obtained showed no statistically significant difference between the three groups, the result being p=0,442, however the group composed of calcium hydroxideP.A. cement associated with MTA and propylene glycol showed a good filling quality (100%) in relation to the other evaluated cements, which were satisfactory (40%) and good (60%) in apexification procedure. There was no significant difference in quality of plug apical filling in the groups, however the group composed of calcium hydroxide P.A cement associated with MTA and propylene glycol showed a superior result(AU)


Subject(s)
Root Canal Filling Materials , Root Canal Obturation , Root Canal Therapy , Calcium Hydroxide
19.
Braz. j. oral sci ; 20: e214873, jan.-dez. 2021. ilus
Article in English | LILACS, BBO | ID: biblio-1254742

ABSTRACT

Aim: To compare the marginal fit of lithium disilicate CAD/CAM crowns and heat-pressed crowns fabricated using milled wax patterns, and evaluate its effect on stress distribution in implantsupported rehabilitation. Methods: A CAD model of a mandibular first molar was designed, and 16 lithium disilicate crowns (8/group) were obtained. The crown-prosthetic abutment set was evaluated in a scanning electron microscopy. The mean misfit for each group was recorded and evaluated using Student's t-test. For in silico analysis, a virtual cement thickness was designed for the two misfit values found previously, and the CAD model was assembled on an implant-abutment set. A load of 100 N was applied at 30° on the central fossa, and the equivalent stress was calculated for the crown, titanium components, bone, and resin cement layer. Results: The CAD/CAM group presented a significantly (p=0.0068) higher misfit (64.99±18.73 µm) than the heat-pressed group (37.64±15.66 µm). In silico results showed that the heat-pressed group presented a decrease in stress concentration of 61% in the crown and 21% in the cement. In addition, a decrease of 14.5% and an increase of 7.8% in the stress for the prosthetic abutment and implant, respectively, was recorded. For the cortical and cancellous bone, a slight increase in stress occurred with an increase in the cement layer thickness of 5.9% and 5.7%, respectively. Conclusion: The milling of wax patterns for subsequent inclusion and obtaining heat-pressed crowns is an option to obtain restorations with an excellent marginal fit and better stress distribution throughout the implant-abutment set


Subject(s)
Microscopy, Electron, Scanning , Computer-Aided Design , Dental Marginal Adaptation , Dental Prosthesis, Implant-Supported , Finite Element Analysis , Dental Materials
20.
Rev. estomat. salud ; 29(2): 1-8, 20210915.
Article in Spanish | LILACS-Express | LILACS | ID: biblio-1353537

ABSTRACT

Antecedentes: En la odontología siempre se ha buscado la implementación de alternativas más conservadoras para el manejo de la caries dental, siendo en este caso una de las opciones el uso de Fluoruro Diamino de Plata más Yoduro de Potasio, el cual es un producto que de fácil aplicación que permite la inactivación de la Caries Dental.Objetivo:Determinar si es viable uso de Fluoruro Diamino de Plata más Yoduro de Potasio para la inactivación de lesiones cariosas. Materiales y Métodos:Estudio descriptivo cualitativo transversal para el cual se realizó una revisión de la literatura reciente asociada a revistas con bases de datos indexadas. Resultados:Se obtuvieron un total de 103 artículos, los cuales fueron analizados y seleccionados 40, siendo excluidos 63 por no cumplir los criterios de inclusión. Conclusión:El uso de Fluoruro Diaminode Plata más Yoduro de Potasio para la inactivación de lesiones cariosas, resulta ser una alternativa eficaz para evitar la emisión de partículas de aerosol, reduciendo en gran medida el riesgo de contagio del COVID-19 durante el tratamiento dental


Background: In dentistry, the implementation of more conservative alternatives for the management of dental caries has always been sought. One option is the use of Silver Diamine Fluoride plus Potassium Iodide, which is a product easy to apply and allows the inactivation of dental caries.Aim:To determine if it is feasible to use Silver Diamine Fluoride plus Potassium Iodide for the inactivation of carious lesions. Materials and methods:This is a retrospective cross-sectional documentary qualitative descriptive study for which a review of recent literature associated with journals with indexed databases was carried out. Results:A total of 103 articles were obtained, which were analyzed and 40 of the 103 were selected, for the reason that the remaining 63 did not meet the inclusion criteria. Conclusion:The use of Silver Diamine Fluoride plus Potassium Iodide for the inactivation of carious lesions, turns out to be an effective and viable alternative, that reduce the emission of aerosol particles, thus reducing the risk of infection of N-COVID-19 during dental treatment

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