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The aim of this study was to determine the immediate and sustained effect of a fluoride varnish and its combinations with toothpastes in preventing root caries development using a salivary microcosm in vitro model. Human root dentin specimens (n = 150) were randomly divided into 5 experimental protocols (n = 30): (1) Fluoride Varnish (V); (2) V followed by Paste One (V + PO); (3) V followed by Paste Plus (V + PP); (4) V followed by PO and PP (V + PO + PP); and (5) No treatment (control). One varnish layer was applied on the specimens (except for the control group) and kept for 18 h. Then, the varnish was removed and toothpaste treatments were initiated according to experimental groups. For the short-term incubation model (n = 15), the specimens were also immediately subjected to 7-day cariogenic challenge. For that, human saliva was used as bacterial inoculum and McBain artificial saliva containing 2% sucrose as growth medium. The other half of the specimens (n = 15) were used to study the varnish's sustained effect by long-term incubation (8 weeks) before cariogenic challenge. The protocols' anti-caries properties were evaluated by dentin porosity (rhodamine intensity; RI) and mineral density, while their anti-biofilm effects were evaluated using biofilm's biomass and viability assays. For short- and long-term incubation models, all experimental regimens resulted in statistically significant decreases (p < 0.05) in the RI (up to 180 µm and 120 µm, respectively) as well as higher mineral density compared to No treatment (p < 0.001). V + PO + PP and/or V + PO resulted in statistically lower RI compared to V for some depths (p < 0.05) in both models. There were changes in RI and mineral density within groups over time. All experimental treatments exhibited anti-biofilm effects. All prevention protocols exhibited immediate and sustained anti-caries effect against root caries development. The combination of a fluoride varnish with PO resulted in superior additional anti-caries effects.

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PURPOSE: To evaluate the in vitro protective effect of a mint formulation containing (-)-epigallocatechin-3-gallate (EGCg-mint) on root dentin exposed to a highly erosive environment in the presence and absence of proteolytic challenge. METHODS: Root dentin specimens were subjected to an erosion-remineralization cycling model (6×/day; 5 days) that included 5-minute immersion in 1% citric acid and 60-minute immersion in remineralization solution (RS). At the remineralization half-time, the specimens were treated (n= 20) with EGCg-mint, RS (negative control) or sodium fluoride (1,000 ppm of NaF; positive control). Half of the specimens were kept overnight in RS (pH cycling) and the other half in RS with Clostridium histolyticum collagenase (pH-proteolytic cycling). Erosion depth was measured using optical profilometry and data analyzed by two-way ANOVA and Tukey tests (α= 0.05). RESULTS: Under pH-cycling, NaF resulted in statistically lower erosion depth compared to EGCg-mint (P= 0.020) and RS (P= 0.005). Under pH-proteolytic cycling, EGCg-mint and NaF significantly decreased the tissue loss (erosion depth, P< 0.001) compared to the RS. The EGCg-mint exhibited an anti-erosion property on root dentin under a proteolytic challenge. NaF presented an anti-erosion property regardless of the erosive cycling model. CLINICAL SIGNIFICANCE: The anti-erosive action of an over-the-counter mint, containing active ingredients, including epigallocatechin-3-gallate, is likely by the protective mechanisms of the dentin extracellular matrix.

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The role of the host immune system in caries progression is mainly speculative, and it is believed that it entails the enzymatic degradation of the dentin organic matrix. The aim of this study was to evaluate the proteolytic effect of human neutrophil enzymes on root caries progression. For this, specimens of bovine root dentin were divided into 4 groups (n = 30): caries (C), caries + neutrophils (C + N), no caries (Control), and no caries + neutrophils (Control + N). Streptococcus mutans biofilm (105 CFU/mL) was grown on the root surface to artificially induce root carious lesions (C and C + N groups). Specimens were then exposed to neutrophils (5 × 106 cells/mL) for 48 h (C + N and Control + N groups). Caries development and neutrophil exposures were repeated a 2nd and 3rd time. Caries depth (CD) and dentin demineralization (DD) were assessed by infiltration of rhodamine B using fluorescence microscopy. Collagen fibril ultrastructure was characterized under a polarized microscope with Picrosirius red staining. There were no significant differences (p > 0.05) in CD and DD between the C and C + N groups for 1, 2, and 3 caries-neutrophil exposures. Immature collagen was significantly less present in the carious groups (C, p = 0.003; C + N, p = 0.01) than in the noncarious groups in the most superficial 200 µm. We thus concluded that human neutrophil enzymes did not influence short-term root caries progression, and immature collagen fibrils were more susceptible to degradation during S. mutans-induced root caries progression.

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This study investigated the contribution of small leucine rich proteoglycans (SLRPs) to the fracture toughness of the dentin extracellular matrix (ECM) by enzymatically-assisted selective removal of glycosaminoglycan chains (GAGs) and proteoglycans (PGs) core protein. We adapted the Mode III trouser tear test to evaluate the energy required to tear the dentin ECM. Trouser-shaped dentin specimens from crown and root were demineralized. Depletion of GAGs and PGs followed enzymatic digestion using chondroitinase ABC (c-ABC) and matrix metalloproteinase 3 (MMP-3), respectively. The legs from specimen were stretched under tensile force and the load at tear propagation was determined to calculate the tear energy (T, kJ/m2). SLRPs decorin and biglycan were visualized by immunohistochemistry and ECM tear pattern was analyzed in SEM. Results showed T of crown ECM was not affected by PGs/GAGs depletion (p = 0.799), whereas the removal of PGs significantly reduced T in root dentin ECM (p = 0.001). Root dentin ECM exhibited higher T than crown (p < 0.03), however no regional difference are present after PG depletion (p = 0.480). Immunohistochemistry confirmed removal of GAGs and PGs. SEM images showed structural modifications after PGs/GAGs removal such as enlargement of dentinal tubules, increased interfibrillar spaces and presence of untwisted fibrils with increased diameter. Findings indicate that the capacity of the PGs to unfold and untwist contribute to the dentin ECM resistance to tear, possibly influencing crack growth propagation. The regional differences are likely an evolutionary design to increase tooth survival, that undergoes repetitive mechanical loading and load stress dissipation over a lifetime of an individual.

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Collagen glycation takes place under physiological conditions during chronological aging, leading to the formation of advanced glycation end-products (AGEs). AGEs accumulation induces non-enzymatic collagen cross-links increasing tissue stiffness and impairing function. Here, we focused on determining the cumulative effect of induced glycation on the mechanical behavior of highly collagen cross-linked dentin matrices and assess the topical inhibition potential of aminoguanidine. Bulk mechanical characterization suggests that early glycation cross-links significantly increase the tensile strength and stiffness of the dentin matrix and promote a brittle failure response. Histologically, glycation yielded a more mature type I collagen in a densely packed collagen matrix. The time-dependent effect of glycation indicates cumulative damage of dentin matrices that is partially inhibited by aminoguanidine. The regional dentin sites were differently affected by induced-glycation, revealing the crown dentin to be mechanically more affected by the glycation protocol. These findings in human dentin set the foundation for the proposed in vitro ribose-induced glycation model, which produces an early matrix stiffening mechanism by reducing tissue viscoelasticity and can be partially inhibited by topical aminoguanidine.

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OBJECTIVES: Surface conditioning of enamel and dentin is a key step during adhesive restorative procedures and strategies. The aim of this study was to investigate the effectiveness of five α-hydroxy-acids (AHAs) as enamel and dentin surface etchants. METHODS: Enamel and dentin specimens were prepared from human molars to determine the depth of demineralization by optical profilometry (Δz), the resin bond strength to enamel and dentin (µTBS), the micro-permeability of dentin-resin interfaces, and the gelatinolytic activity of dentin matrix induced by AHAs [glycolic (GA), lactic (LA), citric (CA), malic (MI) and tartaric (TA)] and controls [phosphoric (PA) and maleic (MA)]. All acids were prepared at 35% concentration. Adhesion studies employed Adper Single Bond Plus bonding system. Data were individually processed and analyzed by ANOVA, post-hoc tests and Pearson correlations (α = 0.05). RESULTS: AHA exhibited statistically lower depth of demineralization of enamel and dentin (average 4 fold) than controls (p < 0.001). In enamel, MA and PA etching resulted in higher µTBS than AHA groups (p < 0.001). In dentin, GA, TA, CI and LA etching resulted in statistically similar µTBS than PA (p < 0.05). The hybrid-layer (HL) thickness and interfacial micro-permeability intensity were statistically lower for AHA groups (p < 0.05). A significant positive correlation was observed between the intensity of micro-permeability and the thickness of HL (p < 0.05). AHA etchants elicited lower dentin enzymatic activity than controls (p < 0.05). SIGNIFICANCE: AHAs effectively etched enamel and dentin surfaces. In particular, GA and TA resulted in suitable µTBS and sealing ability as well as induced less gelatinolytic activity in dentin than PA and MA.

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This study investigated the remineralization effect of experimental mint formulations containing bioactive agents (xylitol; green tea extract, GT; and amorphous calcium phosphate, ACP) in the progression of artificially induced root caries. Root caries lesions were induced by demineralization solution (pH 4.6; 96 h; 37°C). The lesions were treated with mint A, mint B, mint C, xylitol, GT, ACP, or remineralization solution (RS; negative control). Specimens were pH-cycled through treatments (5×/day; 3 min) and 6 cycles of acidic (pH 5.0; 30 min) and neutral (pH 7.0; 10 min) buffers for 8 days. Bacterial collagenase (Clostridium histolyticum) was used overnight to simulate proteolytic challenge. Caries depth and porosity as well as mineral density were estimated using fluorescence microscopy (n = 15) and microcomputed tomography (n = 6). Analysis of variance (ANOVA, α = 0.05) showed no statistically significant difference in caries depth among all groups (p = 0.172). The highest fluorescence intensity decrease was observed for GT followed by mint C, with no significant difference between them (p = 0.868). There were significant differences among GT and mints A, B, and C when compared to RS (p < 0.001). No statistically significant differences in fluorescence intensity were observed among ACP, xylitol, and RS (p > 0.05). The mineral density of the lesions in GT, mints A, B, and C, and ACP was statistically similar (p > 0.05) and significantly higher than that in RS (p < 0.05). No significant difference was observed between xylitol and RS (p = 0.728). The experimental mints showed remineralization action on artificial root caries, and GT was found to be the main active ingredient in the investigated formulations.

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Dental caries is the most prevalent infectious chronic disease in children and adults. With a globally aging population, new demands in the management of dental caries are awakened by the rampant increase in the incidence of dental root caries. Like crown caries, root caries requires bacterial driven tissue demineralization followed by the degradation of the extracellular dentin matrix. Due to the complex composition and ultrastructure, preventive strategies targeting the mineral phase of dentin are insufficient for managing the prevention and progression of root caries. However, the composition and ultrastructure of dentin has inspired novel strategies for the effective management of highly susceptible root surfaces. Specifically, the complex and dynamic dentin extracellular matrix (ECM). The ECM of mature dentin contains a robust type I collagen fibrils scaffold, and carefully distributed non-collagenous components, such as proteoglycans, phosphoproteins, and proteases. In this chapter, we will review the experimental strategies of potential clinical impact to prevent root caries progression by site modifications of the mature extracellular dentin matrix. This approach, termed dentin biomodification, encompasses bioinspired strategies to locally enhance the biological and biomechanical characteristics of the tissue by mimicking natural processes. Here, synthetic and biosynthetic compounds can decrease the biodegradability of the dentin ECM and provide mechanical enhancement of dentin. The resulting effect is the maintenance of the dentin ECM to halt root caries progression and possibly mediate effective remineralization of the caries affected root dentin.

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AIM: The aim of the present study was to evaluate the effect of surface roughness (roughness average [Ra] µm) on the hydrophobicity of a denture-base acrylic resin and the initial adherence and biofilm formation of Candida albicans (C. albicans). METHODS: Disk-shaped specimens were divided into six groups: Ra 0.05, Ra 0.2, Ra 0.4, Ra 0.8, Ra 1.5, and Ra 3.0. Water contact angles (WCA) were measured, and the specimens incubated with C. albicans for 90 min (initial adherence, n = 108) or 48 h (biofilm formation, n = 108). Adhered and biofilm cells were evaluated by c.f.u./mL and 2,3-bis-(2-methoxy-4-nitro-5-sulfophenyl)-2H-tetrazolium-5-carboxanilide (XTT), and the correlation between the two methods was evaluated. The surface of the specimens and cells (adhered and biofilm) were also analyzed by scanning electron microscopy (SEM). RESULTS: Groups Ra 0.05 and 3.0 exhibited the lowest (~75°) and the highest (~100°) WCA mean values, respectively. For both initial adherence and biofilm formation, no statistically-significant differences were observed among all groups, as determined by c.f.u./mL and XTT. A positive correlation between these two methods was found. SEM analysis showed the presence of scratches and valleys on the acrylic specimens and densely-packed yeast cells covering the entire surface. CONCLUSIONS: Roughness significantly increased hydrophobicity (WCA), but had no effect on the number and metabolic activity of adherent and biofilm cells of C. albicans.

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AIMS: The effect of reinforcement and cyclic loading on the resistance to impact (RI) of denture base biopolymer materials was evaluated using Charpy (C) and falling-weight (FW) impact tests. METHODS: Bar-shaped (60×6×2mm(3)) and denture-shaped specimens (2mm) for the C and FD tests, respectively, were prepared with Lucitone 550 (L) and Vipi Wave (V) and relined (2mm) using the same material or the autopolymerizing relining resins Tokuyama Rebase II (T) and Ufi Gel Hard (U). Bulk specimens (60×6×4mm(3)) of all materials (L, V, T and U) were also prepared and tested. To evaluate the effect of reinforcement, glass flakes were added to the powder of the relining resins T and U (5% by weight). Half of bar-shaped (n=320) and half of the denture-shaped specimens (n=480) were subjected to cyclic loading (10,000 cycles) before the impact tests. RESULTS: Data were analyzed by one-way ANOVAs (α=0.05) and revealed that the RI of L and V were comparable and higher than those of U and T. Compared to L and V, the RI was increased by relining with T and decreased by relining with U. When relining was made using the same material (L and V) the RI was maintained. Flexural cyclic loading and the incorporation of glass flakes into the resins T and U did not cause any significant alteration in the RI. A high correlation between results from C and FW tests was observed (r=0.8854). CONCLUSION: Relining may exert effects on the RI of L and V denture base resins, which vary according to the relining material used. The high correlation between C and FW, suggests that the Charpy test, using bar-shaped specimens, can be a simple and reliable method for evaluating factors that may influence the RI of denture base polymers.

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AIMS: To compare the effectiveness of adding cyclobenzaprine, tizanidine, or placebo to patient education and a self-care management program for patients with myofascial pain and specifically presenting with jaw pain upon awakening. METHODS: Forty-five patients with a diagnosis of myofascial pain based on the guidelines of the American Academy of Orofacial Pain participated in this 3-week study. The subjects were randomly assigned into one of three groups: placebo group, TZA group (tizanidine 4 mg), or CYC group (cyclobenzaprine 10 mg). Patients were evaluated for changes in pain intensity, frequency, and duration by using the modified Severity Symptoms Index and changes in sleep quality with the use of the Pittsburgh Sleep Quality Index. Data were analyzed by ANOVA and post-hoc or nonparametric statistical tests as appropriate. RESULTS: All three groups had a reduction in pain symptoms and improvement of sleep quality based on a comparison of pretreatment and treatment scores. However, no significant differences among the groups were observed at the posttreatment evaluation. CONCLUSION: The use of tizanidine or cyclobenzaprine in addition to self-care management and patient education was not more effective than placebo for the management of patients with myofascial jaw pain upon awakening.

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PURPOSE: This study evaluated whether photopolymerised coatings containing zwitterion or hydrophilic monomers would reduce the adhesion of Candida albicans to an acrylic resin. MATERIALS AND METHODS: Disc-shaped samples (n = 468) were fabricated with rough or smooth surfaces. The samples did not receive any surface treatment (control) or were coated with one of the following experimental coatings (2-hydroxyethyl methacrylate - HE; 3-hydroxypropyl methacrylate - HP; and 2-trimethylammonium ethyl methacrylate chloride - T; and sulfobetaine methacrylate - S). The concentrations of the constituent monomers were 25, 30 or 35%. The water contact angles of the samples were measured, and half of the samples were exposed to saliva. The adherent yeast cells were counted after crystal violet staining. RESULTS: For the smooth samples, the groups S35, HP35 and HE35 showed significantly lower number of adhered Candida than control, in the absence of saliva. There were no significant differences among the experimental and control groups for the rough samples, but the saliva decreased the cell numbers for groups S25, S30 and HP30. The photoelectron spectroscopy analysis confirmed the changes in the chemical compositions of the experimental samples. CONCLUSIONS: The experimental photopolymerised coatings changed the chemical composition and decreased C. albicans adhesion in the groups S35, HP35 and HE35, suggesting that they should be further investigated.

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This study evaluated the potential of plasma treatments to modify the surface chemistry and hydrophobicity of a denture base acrylic resin to reduce the Candida glabrata adhesion. Specimens (n = 54) with smooth surfaces were made and divided into three groups (n = 18): control - non-treated; experimental groups - submitted to plasma treatment (Ar/50 W; AAt/130 W). The effects of these treatments on chemical composition and surface topography of the acrylic resin were evaluated. Surface free energy measurements (SFE) were performed after the treatments and after 48 h of immersion in water. For each group, half (n = 9) of the specimens were preconditionated with saliva before the adhesion assay. The number of adhered C. glabrata was evaluated by cell counting after crystal violet staining. The Ar/50 W and AAt/130 W treatments altered the chemistry composition, hydrophobicity and topography of acrylic surface. The Ar/50 W group showed significantly lower C. glabrata adherence than the control group, in the absence of saliva. After preconditioning with saliva, C. glabrata adherence in experimental and control groups did not differ significantly. There were significant changes in the SFE after immersion in water. The results demonstrated that Ar/50 W treated surfaces have potential for reducing C. glabrata adhesion to denture base resins and deserve further investigation, especially to tailor the parameters to prolong the increased wettability.

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OBJECTIVE: This study investigated the effect of experimental photopolymerized coatings, containing zwitterionic or hydrophilic monomers, on the hydrophobicity of a denture base acrylic resin and on Candida albicans adhesion. METHODS: Acrylic specimens were prepared with rough and smooth surfaces and were either left untreated (control) or coated with one of the following experimental coatings: 2-hydroxyethyl methacrylate (HE); 3-hydroxypropyl methacrylate (HP); and 2-trimethylammonium ethyl methacrylate chloride (T); and sulfobetaine methacrylate (S). The concentrations of these constituent monomers were 25%, 30% or 35%. Half of the specimens in each group (control and experimentals) were coated with saliva and the other half remained uncoated. The surface free energy of all specimens was measured, regardless of the experimental condition. C. albicans adhesion was evaluated for all specimens, both saliva conditioned and unconditioned. The adhesion test was performed by incubating specimens in C. albicans suspensions (1×10(7)cell/mL) at 37°C for 90min. The number of adhered yeasts were evaluated by XTT (2,3-bis[2-methoxy-4-nitro-5-sulfophenyl]-5-[{phenylamino}carbonyl]-2H-tetrazolium-hydroxide) method. RESULTS: For rough surfaces, coatings S (30 or 35%) and HP (30%) resulted in lower absorbance values compared to control. These coatings exhibited more hydrophilic surfaces than the control group. Roughness increased the adhesion only in the control group, and saliva did not influence the adhesion. The photoelectron spectroscopy analysis (XPS) confirmed the chemical changes of the experimental specimens, particularly for HP and S coatings. CONCLUSIONS: S and HP coatings reduced significantly the adhesion of C. albicans to the acrylic resin and could be considered as a potential preventive treatment for denture stomatitis.

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OBJECTIVE: In studies on Candida albicans adhesion to surfaces, diverse protocols have been used for collection and preparation of saliva samples. Thus, this study investigated whether variations in the centrifugation parameters and number of donors of saliva would influence the adhesion of C. albicans to a denture base resin. METHODS: Resin acrylic samples (n = 72) were made and then divided into four groups: (a) control - specimens were left without preconditioning in saliva; (b) three experimental groups, in which the specimens were preconditioned with saliva collected from 15 volunteers and centrifuged at 12 000 g for 5 min (G1 ); from 15 volunteers and centrifuged at 18 000 g for 30 min (G2 ); and from one volunteer and centrifuged at 12 000 g for 5 min (G3 ). Candida adhesion was evaluated by both the 2,3-bis(2-methoxy-4-nitro-5-sulfophenyl)-5-[(phenylamino) carbonyl]-2H-tetrazolium hydroxide (XTT) reduction method and crystal violet staining. Data were analyzed by one-way analyses of variance (P = 0.05). RESULTS: For XTT reduction assay, groups G2 , G3 , and control were not significantly different, whereas group G1 showed significantly higher absorbance value than control. For crystal violet staining there were no significant differences among all groups. CONCLUSION: Variations in the centrifugation parameters and number of donors of saliva may influence C. albicans adhesion to denture base resins.

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O presente estudo avaliou o número dos contatos oclusais obtidos em próteses provisórias unitárias sobre implantes posteriores, montadas em articulador semi-ajustável a partir da utilização de arco facial e de plano de Camper. Dez pacientes que procuraram uma clínica particular foram selecionados para confecção de próteses sobre implantes unitários previamente instalados. Para cada paciente foram confeccionadas duas próteses provisórias, obtidas sob diferentes condições: (1) montagem dos modelos utilizando arco facial e (2) montagem com plano de Camper. As próteses foram confeccionadas e ajustadas em laboratório, e instaladas por um único operador. Os contatos oclusais obtidos em cada condição foram evidenciados e fotografados, sendo então submetidos à avaliação e quantificação por um segundo profissional, cego para as condições de montagem. Os números obtidos foram submetidos ao teste de Mann Witney, e um nível de 5 por cento de significância foi utilizado. Não houve diferença estatisticamente significante entre os números de contatos oclusais, quando as próteses foram confeccionadas com arco facial ou plano de Camper (p> 0,05). Para confecção de próteses provisórias unitárias sobre implantes posteriores, o uso do plano de Camper para montagem em articulador não diferiu significantemente do arco facial, considerando o número de contatos oclusais(AU)

Este estudio evaluó el número de los contactos oclusales obtenidos en las prótesis temporales, montados en articulador semiajustable por el uso de arco facial y el plano de Camper. Diez pacientes que buscaron una clínica privada fueron seleccionados para las prótesis de implantes unitarios previamente instalados. Para cada paciente se hicieron dos prótesis temporales, que fueron obtenidas bajo condiciones diferentes: montaje de modelos con uso de arco facial y montaje con plano de Camper. Las prótesis fueron hechas, ajustadas e instaladas por un solo operador en el laboratorio. Los contactos oclusales obtenidos en cada condición fueron fotografiados y sometidos a la evaluación y cuantificación a través de un segundo profesional, ciego a las condiciones de montaje. Los números obtenidos fueron analizados mediante el examen de Mann-Whitney y un nivel de 5 por ciento de significación fue utilizado. No hubo diferencia estadísticamente significativa entre el número de contactos oclusales cuando las prótesis fueron hechas con arco facial o plano de Camper (p= 0,113). Para la confección de la prótesis dental temporal más tarde, el uso de montaje articular con plano de Camper no difirió significativamente del arco facial, respecto al número de contactos oclusales(AU)

To assess the number of occlusal contacts achieved in temporal prostheses mounted in a semi-adjusted articulator using the facial arch and the Camper plane. Ten patients treated in a private clinic were selected to be rehabilitated with prostheses in previously placed single implants. For each patient two temporal prostheses were designed obtained under different conditions: (1) model mounting using facial arch and (2) Camper plane mounting. Prostheses were made and adjusted in the laboratory and placed only by an operator. The occlusal contacts achieved in each condition were photographed being assessed and quantified by a second professional not involved with the mounting conditions. Results obtained were analyzed by Mann-Whitney test with a 5 percent significance level. There was not a statistically difference between the number of occlusal contacts when prostheses were made with facial arch or Camper plane (p= 0.113). The temporal dental prosthesis confection for single implants, semi-adjusted articulator using the Camper plane, not differ very much from the facial arch use, according to the number of resulting occlusal contacts(AU)

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Estudos recentes têm demonstrado resultados consistentes com o uso das terapias físicas nos casos de dor e limitação de movimentos em Disfunção Temporomandibular (DTM). Dessa forma, nosso objetivo foi avaliar o efeito de dez sessões de fisioterapia, exercícios e laserterapia no tratamento da dor muscular e da artralgia em uma mulher com DTM. O alívio médio dos sintomas dolorosos obtidos por sessão foi de 20 por cento, atingindo valor zero nas últimas semanas e mantendo-se estável por 60 dias após o término do tratamento. Os resultados demonstraram que o protocolo de tratamento utilizado foi efetivo no alívio da dor da região articular, assim como da tensão do músculo masseter, levando a paciente a reduzir a ingestão de medicamentos para controle da dor. Entretanto, estudos adicionais são necessários para se definir com maior precisão o efeito de outros programas de fisioterapia, assim como sua interação com as demais modalidades de tratamento(AU)

Estudios recientes han demostrado resultados consistentes con el uso de la terapia física en casos de dolor y limitación del movimiento por disfunción temporomandibular. Esta investigación tuvo como objetivo evaluar el efecto de 10 sesiones de terapia física, ejercicio y terapia por láser en el tratamiento del dolor muscular y artralgias en una mujer con disfunción temporomandibular. El alivio de los síntomas dolorosos obtenido por sesión fue sobre un 20 por ciento al acercarse a 0 en las últimas semanas y se mantuvo estable después de 60 días de finalizar el tratamiento. Los resultados mostraron que el protocolo de tratamiento utilizado fue eficaz para reducir el dolor de la articulación temporomandibular y la tensión del músculo masetero, a su vez le permitió al paciente reducir el uso de medicamentos. Sin embargo, son necesarios más estudios para definir con mayor precisión el efecto de otros programas de fisioterapia y su interacción con otras modalidades de tratamiento(AU)

Recent studies have shown consistent results using the physical therapy in cases of pain and limitation of movement from temporomandibular dysfunction. Thus, our objective was to assess the effect of ten sessions of physical therapy and laser therapy in treatment of muscular pain and arthralgias in a woman with temporomandibular dysfunction. The painful symptoms relief achieved by session was over 20 percent, up to zero at the end of treatment. Results demonstrated that the treatment protocol used was effective to reduce the temporomandibular joint and the masseter muscle tension and a decreased of drugs by patient. However, more studies are needed to define with more accuracy the effect of other physiotherapy programs and its interaction with other treatment modalities(AU)

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O objetivo deste estudo foi avaliar a influência dos parâmetros de digitalização na qualidade da imagem radiográfica digital, com relação a reparos anatômicos. Para isso, imagens radiográficas foram digitalizadas por meio de um scanner (n = 160) com resoluções de 300, 600 e 2400 dpi. As imagens de 2400 dpi foram ainda diminuídas para 300 e 600 dpi antes do armazenamento. As digitalizações foram realizadas com e sem máscaras pretas utilizando-se escalas de cinza de 8-bit e 16-bit e salvas em formato tiff. Para avaliar a influência dos parâmetros dedigitalização na qualidade da imagem radiográfica digitalizada, quatro reparos anatômicos foram classificados por dois observadores (muito boa, boa, moderada, regular, pobre) em duas ocasiões diferentes. As concordâncias intra e inter-observadores foram avaliadas por meio do teste Kappa. Os resultados obtidos demonstraram que as concordâncias intra e inter-observadores variaram em função dos reparos anatômicos e da resolução utilizada. A junção cemento esmalte foi o reparo anatômico que apresentou a mais pobre concordância. A utilização da máscarapreta favoreceu a qualidade da imagem digitalizada e seu uso é necessário para cobrir a radiografia durante o processo de digitalização. Portanto, a concordância variou de regular a moderada para a avaliação intra-observador e de regular a pobre para a concordância inter-observador.

The aim of this study was to evaluate the influence of digitization parameters on periapical radiographic image quality, with regard to anatomic landmarks. digitized images (n = 160) were obtained using a flatbed scanner with resolutions of 300, 600 and 2400 dpi. the radiographs of 2400 dpi were decreased to 300 and 600 dpi before storage. Digitizations were performed with and without black masking using 8-bit and 16-bit grayscale and saved in tiff format. Four anatomic landmarks were classified by two observers (very good, good, moderate, regular, poor), in two random sessions. Intraobserver and interobserver agreements were evaluated by Kappa statistics. Inter andintraobserver agreements ranged according to the anatomic landmarks and resolution used. The results obtained demonstrated that the cement enamel junction was the anatomic landmark that presented the poorest concordance. The use of black masking provided better results in the digitized image. the use of a mask to cover radiographs during digitization is necessary. therefore, the concordance ranged from regular to moderate for the intraobserver evaluation and concordance ranged from regular to poor for interobserver evaluation.

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A adesão de Candida às superfícies protéticas é o passo inicial para ocorrência da estomatite protética. Entre os diversos fatores envolvidos na adesão de Candida spp. às superfícies poliméricas estão as interações hidrofóbicas e eletrostáticas, a rugosidade superficial e a película salivar. Assim, os objetivos deste estudo foram: investigar o potencial de diferentes tratamentos a plasma (Ar/50W; ArO2/70W; AAt/130W; ArSF6/70W) de modificar uma resina acrílica para base de prótese (VIPIWAVE) para reduzir a aderência de Candida albicans (ATCC 90028), avaliada pelo ensaio de XTT e cristal violeta. O efeito da rugosidade de superfície e do pré-condicionamento com saliva também foram avaliados; investigar se modificações de superfícies por meio de dois tratamentos a plasma (Ar/50W; AAt/130W) reduziriam a aderência de Candida glabrata (ATCC 2001), avaliada pela coloração cristal violeta, sobre superfícies lisas de resina acrílica. Além disso, o efeito do pré-condicionamento com saliva também foi avaliado; e ainda, avaliar se variações nos períodos de pré-condicionamento com saliva (0 min; 30 min; 60 min; 180 min; 720 min), nos parâmetros de centrifugação (velocidade e tempo) e número de doadores de saliva influenciariam os resultados de adesão de Candida albicans a uma resina acrílica para base de prótese, avaliada por meio do ensaio de XTT e coloração cristal violeta. Além disso, a correlação entre os dois métodos utilizados para avaliação da adesão de Candida albicans também foi avaliada. Os resultados obtidos demonstraram que os tratamentos a plasma são efetivos para modificação da hidrofobicidade de superfície ou incorporação de átomos de flúor na superfície da resina acrílica. Entretanto, após os tratamentos a plasma e imersão das amostras em água, houve alterações significantes nos valores médios de ângulo de contato obtidos. Os grupos ArO2/70W e ArSF6/70 W apresentaram menores valores de absorbância para a adesão de Candida albicans comparados aos outros grupos. Nenhuma diferença significante foi observada entre os grupos tratados a plasma e o grupo controle, quando a adesão de Candida albicans foi avaliada por meio da coloração cristal violeta, independente da rugosidade superficial e presença ou ausência de saliva. O número de Candida glabrata aderida, avaliado pela coloração cristal violeta, foi significantemente menor no grupo tratado com Ar/50W comparado ao grupo controle, na ausência de saliva. Entretanto, na presença de précondicionamento com saliva, nenhuma diferença significante foi observada entre os grupos experimentais e controle para adesão de Candida glabrata. Os diferentes períodos de pré-condicionamento com saliva não influenciaram significantemente a adesão de Candida albicans, entretanto, os parâmetros de centrifugação (velocidade e tempo) e o número de doadores de saliva influenciaram significantemente os resultados de adesão de Candida albicans à resina acrílica avaliada. Nenhuma correlação significante foi encontrada entre os métodos utilizados para avaliação da adesão de Candida albicans, coloração cristal violeta e ensaio de XTT. Portanto, os tratamentos a plasma com ArO2/70W e ArSF6/70W demonstraram-se promissores para redução da adesão de Candida albicans, enquanto o tratamento a plasma com Ar/50W apresentou resultado promissor para redução da adesão de Candida glabrata à resina acrílica avaliada. Além disso, a película de saliva, dependendo das condições experimentais, pode aumentar a adesão de Candida albicans, mas não altera significantemente a adesão de Candida glabrata. As variações metodológicas relacionadas ao pré condicionamento com saliva influenciaram os resultados de adesão de Candida albicans

The adhesion of Candida to denture surfaces is the initial step for occurrence of denture stomatitis. Among the various factors involved on Candida adhesion to polymeric surfaces are the hydrophobic and eletrostatic interactions, surface roughness and pellicle salivary. Hence, the aims of this study were: to investigate the potential of different plasma treatments (Ar/50W; ArO2/70W; AAt/130W; ArSF6/70W) to modify a denture base acrylic resin (VIPIWAVE) to reduce the Candida albicans adhesion (ATCC 90028), evaluated by XTT reduction assay and crystal violet staining. The effect of surface roughness and saliva coating was also evaluated; to investigate the potential of two plasma treatments (Ar/50W; AAt/130W) to modify a denture base acrylic resin to reduce the Candida glabrata adhesion (ATCC 2001), evaluated by crystal violet staining. Moreover, the effect of saliva coating was also evaluated; and to assess the effect of different periods of preconditioning with saliva (0 min; 30 min; 60 min; 180 min; 720 min), variations in the centrifugation parameters (speed and time) and number of donors of saliva on Candida albicans adhesion to a denture base resin using crystal violet staining and XTT reduction assay. Additionally, the correlation between the two methods used for assessing Candida albicans adhesion was also evaluated. The results obtained demonstrated that the plasma treatments were effective in modifying hydrophobicity or incorporation of fluorine into acrylic resin. However, there were significant alterations in the contact angle measured after immersion in water. Groups ArO2/70W and ArSF6/70W showed significantly lower absorbance readings to Candida albicans adhesion than the other groups. No statistically significant difference in the adherence of Candida albicans, evaluated by crystal violet staining, was observed between the plasma treated and control groups, irrespective of the presence or absence of saliva, and surface roughness. The number of adhered Candida glabrata, evaluated by counting after crystal violet staining, was significantly lower in Ar/50W group than the control group, in the absence of saliva. However, after preconditioning with saliva, Candida glabrata adherence in experimental and control groups did not differ significantly. The different periods of preconditioning with saliva had no significant influence in the Candida albicans adhesion, but the centrifugation parameters (speed and time) and number of donors of saliva influenced the results of Candida albicans adhesion to the denture base acrylic resin. No significant correlation was found between the two methods used for assessing Candida albicans adhesion, crystal violet staining and XTT reduction method. Thus, the results demonstrated that ArO2/70W and ArSF6/70W plasma treatments showed promising potential for reducing Candida albicans adhesion, while the Ar/50W plasma treatment showed promising potential for reducing Candida glabrata adhesion to denture base resins. Moreover, the saliva pellicle, depending of experimental conditions, may increase the Candida albicans adhesion, but it not significantly influences the Candida glabrata adhesion. The diverse methodological procedures regarding to preconditioning with saliva alter the results of Candida albicans adhesion

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UNLABELLED: The adhesion of Candida albicans to surfaces is the prerequisite for occurrence of denture stomatitis. OBJECTIVE: Hence, this study investigated if surface modifications with plasma treatments could reduce the adherence of C. albicans to a denture base resin. METHODS: Specimens (n=180) with roughened and smooth surfaces were made and divided into five groups: control-specimens were left untreated; experimental groups-specimens were submitted to plasma treatments to obtain surfaces with different hydrophobicity (Ar/50W; ArO2/70W; AAt/130W) or incorporation of fluorine (Ar/SF(6)70W). Contact angle measurements were performed immediately after the treatments and after immersion in water for 48h. For each group, half of the specimens were incubated with saliva prior to the adhesion assay. The number of adherent yeasts was evaluated by XTT reduction method. RESULTS: For the experimental groups, there was significant change in the mean contact angle after 48h of immersion in water. Groups ArO2/70W and ArSF6/70W showed significantly lower absorbance readings than the other groups, regardless the presence or absence of saliva and surface roughness. CONCLUSIONS: Results demonstrated that ArO2/70W and ArSF6/70W plasma treatments showed promising potential for reducing the adherence of C. albicans to denture base resins.

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