ABSTRACT
A interface implante pilar (IAI) por se constituir de duas peças inevitavelmente apresentam micro lacuna (GAP), na qual pode ocorrer infiltração bacteriana, permitindo a penetração de microorganismos que colonizam na parte interna do implante levando ao acúmulo de biofilme e, podendo levar ao desenvolvimento da periimplantite. O desgaste da conexão interna do implante é algo que ocorre com frequência, muitas vezes pela fratura do parafuso e/ou, pela perda da rosca interna do implante. A ausência de informações prévias também pode gerar a necessidade da remoção do implante, devido a estas intercorrências, surge a possibilidade da criação de um novo componente para implantes para possibilitar a reabilitação protética, sem ter que passar por uma nova cirurgia de remoção e instalação do implante. O objetivo do trabalho foi mensurar o nível de afrouxamento do parafuso do pilar protético e do minipilar comparando com novo componente protéticos, na tentativa de simular o comportamento do conjunto implante/pilar/prótese. Foram utilizados vinte implantes de plataforma cone morse (CM) da DSP® com seus respectivos mini pilares, na qual foram distribuídos em 2 grupos(n=10): Grupo 1 - implante CM + mini pilar FlexCone® DSP + coroa simplificada pirâmide invertida carga aplicada 3 mm do centro da coroa. E Grupo 2 - implante CM + mini pilar novo + coroa simplificada pirâmide invertida carga aplicada 3 mm do centro da coroa. Foram realizados ciclagem mecânica com carga 133 N, durante 2x106 ciclos, com frequência 2 Hz e temperatura de 37ºC em ambos grupos. Um torquímetro digital foi usado para medir os valores de torque reverso do parafuso protético da coroa e também do pilar protético, antes e após o carregamento. Os resultados do modelo de regressão demonstraram diferenças estatisticamente significativas em função do envelhecimento comparando os grupos da coroa sobre o pilar protético (p = 0.020) e entre os grupos do pilar sobre o implante (p = 0.048), indicando que após o envelhecimento de 2.000.000 de ciclos ao longo do tempo está associado de maneira significativa a essas variáveis no contexto deste estudo. O segundo objetivo deste estudo foi avaliar in vitro a taxa de infiltração bacteriana através da IAI, entre o novo componente protético e a superfície interna do implante, juntamente foi analisado a permeabilidade do IAI para colonização bacteriana. Um total de oitenta implantes foram testados. As estruturas montadas para grupo 1 foi torqueado com 20 N/cm e do G2 foram torqueados com 45 N, ambos imersos em microtubos contendo 200 µl de saliva humana. Após 14 dias de incubação da amostra de bactéria nos implantes, foi realizada uma análise qPCR (reação da cadeia da polimerase em tempo real). O teste revelou que não houve diferenças estatisticamente significativas no crescimento bacteriana entre os grupos em qualquer um dos pontos temporais analisados. Conclui-se que o novo componente testado apresentou um destoque menor do que comparado ao mini pilar FlexCone DSP® e apresentou infiltração bacteriana no GAP da conexão implante-pilar semelhante comparado ao mini pilar original da empresa (AU)
The abutment implant interface (IAI), as it consists of two pieces, inevitably presents a micro gap (GAP), in which bacterial infiltration can occur, allowing the penetration of microorganisms that colonize in the internal part of the implant, leading to the accumulation of biofilm and, which can lead to development of peri-implantitis. Wear of the implant's internal connection is something that occurs frequently, often due to screw fracture and/or loss of the implant's internal thread. The lack of prior information can also generate the need to remove the implant, due to these complications, the possibility arises of creating a new component for implants to enable prosthetic rehabilitation, without having to undergo a new surgery to remove and install the implant. implant. The objective of the work was to measure the level of screw loosening of the prosthetic abutment and the mini-abutment compared with the new prosthetic component, in an attempt to simulate the behavior of the implant/ abutment/prosthesis set. Twenty DSP® morse cone (CM) platform implants were used with their respective mini pillars, which were distributed into 2 groups (n=10): Group 1 - CM implant + FlexCone® DSP mini pillar + simplified crown inverted pyramid load applied 3 mm from the center of the crown. And Group 2 - CM implant + new mini abutment + simplified crown inverted pyramid load applied 3 mm from the center of the crown. Mechanical cycling was carried out with a load of 133 N, for 2x106 cycles, with a frequency of 2 Hz and a temperature of 37ºC in both groups. A digital torque wrench was used to measure the reverse torque values of the prosthetic crown screw and also the prosthetic abutment, before and after loading. The results of the regression model demonstrated statistically significant differences as a function of aging comparing the crown-on-prosthetic abutment groups (p =0.020) and between the abutment-on-implant groups (p = 0.048), indicating that after aging 2,000 ,000 cycles over time is significantly associated with these variables in the context of this study. The second objective of this study was to evaluate in vitro the rate of bacterial infiltration through the IAI, between the new prosthetic component and the internal surface of the implant, together with the permeability of the IAI for bacterial colonization. A total of eighty implants were tested. The assembled structures for group 1 were torqued with 20 N/cm and G2 were torqued with 45 N, both immersed in microtubes containing 200 µl of human saliva. After 14 days of incubation of the bacteria sample in the implants, a qPCR (real-time polymerase chain reaction) analysis was performed. The test revealed that there were no statistically significant differences in bacterial growth between groups at any of the time points analyzed. It is concluded that the new component tested presented a lower impact compared to the FlexCone DSP® mini abutment and presented bacterial infiltration in the GAP of the implant-abutment connection similar to the company's original mini abutment.(AU)
Subject(s)
Streptococcus mutans , Dental Implants , Peri-ImplantitisABSTRACT
Objetivo. Determinar el efecto antibacteriano del extracto etanólico del té verde (Camellia sinensis) y propóleo a una concentración de 10, 20 y 30% a las 24 y 48 horas sobre Streptococcus mutans. Métodos. Estudio experimental, in vitro, comparativo, con muestra no probabilística de 150 discos de papel, distribuidos en 30 placas Petri previamente preparadas con agar sangre e inoculadas con cepas de Streptococcus mutans, se colocaron tres discos embebidos en extracto etanólico al 10, 20 y 30%, un disco en clorhexidina 0,12% (control positivo) y un disco en agua destilada, fueron llevadas a la incubadora y pasadas las 24 horas y 48 horas se midieron los correspondientes halos de inhibición. Los extractos se obtuvieron mediante un proceso de maceración modificado, en aparato de agitación rotatorio. Resultados. El mayor halo inhibitorio del extracto etanólico de Camellia sinensis (C. sinensis) frente a Streptococcus mutans fue en la concentración al 30% a las 24 h y 48 h, mientras que el mayor halo inhibitorio del extracto etanólico de propóleo, fue en la concentración al 30% a las 24 h, por lo tanto, los extractos naturales mostraron ser sensibles en la escala de Duraffourd. Conclusiones. Se evidenció que el propóleo al 30% mostró un efecto antibacteriano similar a la clorhexidina, considerada gold estándar, el tiempo en el que existió mayor efecto antibacteriano del extracto etanólico de C. sinensis y propóleo frente a Streptococcus mutans, fue a las 24 horas, el diámetro de los halos inhibitorios disminuyó, conforme aumentó el tiempo de exposición al microorganismo.
Objective. To determine the antibacterial effect of the ethanolic extract of green tea (Camellia sinensis) and propolis at a concentration of 10, 20 and 30% at 24 and 48 hours on Streptococcus mutans. Methods. Experimental, in vitro, comparative study, with a non-probabilistic sample of 150 paper discs, distributed in 30 Petri dishes previously prepared with blood agar and inoculated with strains of Streptococcus mutans, were placed 3 discs soaked in ethanolic extract at 10, 20 and 30%, 1 disk in 0.12% chlorhexidine (positive control) and 1 disk in distilled water, they were taken to the incubator and after 24 hours and 48 hours the measurements corresponding to the inhibition halos were made. The extracts were gotten by a modified maceration process, in a rotary stirring apparatus. Results. The highest inhibitory halo of the ethanolic extract of C. sinensis against Streptococcus mutans was in the concentration at 30% at 24 h and 48 h, while the highest inhibitory halo of the ethanolic extract of propolis, was in the concentration at 30% at 24 h; therefore, the natural extracts showed to be sensitive on the Duraffourd scale. Conclusions. It was evidenced that 30% propolis showed an antibacterial effect similar to chlorhexidine, considered gold standard, the time in which there was a greater antibacterial effect of the ethanolic extract of Camellia Sinensis and propolis against Streptococcus mutans, was at 24 hours, taking into account that the diameter of the inhibitory halos decreased, as the exposure time to the microorganism increased
ABSTRACT
BACKGROUND: Dental caries is one of several prevalent oral diseases caused by dental plaque biofilms. This study evaluated the anti-cariogenic effects of a bamboo salt (BS) and sodium fluoride (NaF) mixture on oral bacteria.METHODS: The effects of several mixtures of NaF and BS on acid production, growth, and adhesion to glass beads of Streptococcus mutans, and their anti-cariogenic properties were investigated. The growth of S. mutans was measured according to optical density at 3, 6, 9, 12, 15, 18, and 24 hours after treatment using spectrophotometry at a wavelength of 600 nm, while pH was measured using a pH meter. Adhesion of S. mutans was measured according to the weight of glass beads from each group before and after incubation. Gene expression was measured using real-time polymerase chain reaction. Acid production and growth patterns of S. mutans were compared using repeated measures analysis of variance, followed by Scheffe's post-hoc test. The Kruskal–Wallis test was used to compare adhesion, followed by the Mann–Whitney test. Gene expression in the experimental and control samples was compared using the Student's t-test.RESULTS: Growth, acid production, and adhesion of S. mutans were inhibited in all experimental groups. Expression of gft and fructosyltransferase in S. mutans was inhibited in all groups. A mixture of NaF and BS significantly reduced growth, acid production, adhesion, and gene expression of S. mutans compared with the other groups.CONCLUSION: Results of the present study demonstrated that a mixture of NaF and BS was useful as a mouth rinse in preventing dental caries.
Subject(s)
Bacteria , Biofilms , Dental Caries , Dental Plaque , Gene Expression , Glass , Hydrogen-Ion Concentration , Mouth , Real-Time Polymerase Chain Reaction , Sodium Fluoride , Sodium , Spectrophotometry , Streptococcus mutansABSTRACT
Astragalus produced in Gansu were chosen as the raw material to leachate. Studied the antibiotic effects of the leaching solution on the cariogenic bacteria and compared with the imported bacteriostatic product MI. Streptococcus mutans and Lactobacilli were cultured in the medium for 24 h. The PH and A600 values were measured. Statistical analysis was conducted by using SPSS 13.0. The leaching solution of astragalus has the same inhibitory effects on the growth and acid production of streptococcus mutans and lactobacilli as MI.
ABSTRACT
Objective:To obtain mutA gene of Strepto c occus mutans (Ms),and to express it in E.coli DH5?.Methods: mutA gene was amplified by PCR with specific primers from genome of Ms CH43 strain. After sequencing, the gene segment was inserted into vector pProEX and expressed in E.coli DH5?.The protein expression was induced by ITPG an d the protein products were examined by 180 ml/L SDSPAGE electrophorosis. Results:The length of PCR product was 147 bp and was identical to mu tA gene reported by GenBank.The mutA gene product was expressed in E.col i DH5? with Mr of 5.7?10 3.The maximum mutA protein product amount (20% of the total bacterial protein) was obtained when the A 600 value of DH5? was 1.666,IPTG concerntration 1.0 mmol/L and induction time 6 h.Conclus ion:mutA of Ms CH43 can be cloned and expressed in E.coli DH 5?.
ABSTRACT
Objective: To construct the antheraea pernyi lysozyme(ApLZ) expression system using the methylotrophic yeast Pichia pastoris, to assay the antibacterial activity of the recombinant ApLZ against Streptococcus mutans. Methods:The ApLZ expression system was used in the expression and purity of Ap-lysozyme. The antibacterial activity of the recombinant ApLZ against Streptococcus mutans were assayed by using agar diffusion method. Results:Expression system of ApLZ was constructed using the methylotrophic yeast Pichia pastoris as a host. ApLZ was expressed correctly and secreted efficiently when the native signal sequence of ApLZ was used as secretion signal. The level of ApLZ expression in Pichia pastoris peaks at 96 h after the induction of sustaining 5 ml/L methanol. The molecular weight of the recombinant ApLZ is about 20 000. Conclusion:The recombinant ApLZ is active in inhibiting the growth of Streptococcus mutans.