Candida albicans adherence to an acrylic resin modified by experimental photopolymerised coatings: an in vitro study.

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.

In vitro adhesion of Candida glabrata to denture base acrylic resin modified by glow-discharge plasma treatment.

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.

Effect of experimental photopolymerized coatings on the hydrophobicity of a denture base acrylic resin and on Candida albicans adhesion.

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.

Efeitos dos parâmetros de digitalização na qualidade da imagem radiográfica periapical com relação a reparos anatômicos / Effect of digitization parameters on periapical radiographic image quality with regard to anatomic landmarks

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.

Efeitos de diferentes tratamentos a plasma e de variações na coleta, preparo e pré-condicionamento com saliva na adesão de Candida a uma resina para a base de prótese / Effects of different plasma treatments and variations in the collection, preparation and preconditioning with saliva on Candida adhesion to a denture base acrylic resin

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

Adherence in vitro of Candida albicans to plasma treated acrylic resin. Effect of plasma parameters, surface roughness and salivary pellicle.

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.

Effect of different periods of preconditioning with saliva on Candida albicans adhesion to a denture base resin by crystal violet staining and XTT assay.

AIM: The role of saliva on Candida adhesion to biomaterials has not been clearly defined. The present study investigates whether different periods of preconditioning with saliva would influence the adhesion of Candida albicans to a denture base resin. METHODS: Ninety samples of acrylic resin with smooth surfaces were made and then divided into five groups: one control without saliva, and four experimental groups conditioned in saliva for periods of 30 min, 1, 3, or 12 h. Candida adhesion was evaluated by crystal violet staining and 2,3-bis(2-methoxy-4-nitro-5-sulfophenyl)-5-([phenylamino] carbonyl)-2H-tetrazolium-hydroxide assay. RESULTS: The one-way analysis of variance revealed that there were no significant differences among the mean number of adherent cells or among the mean absorbance for all groups. No significant correlation was found between the two methods used for assessing Candida albicans adhesion. CONCLUSION: The different periods of preconditioning with saliva had no significant influence on the adhesion of Candida albicans to the denture base acrylic resin.

Tratamento de dor de cabeça relacionada com a dor miofascial: relato de caso clínico / Management of headache related to myofascial pain: clinical case report

As dores de cabeça são sintomas usualmente apontados pelos pacientes que sofremde desordens temporomandibulares (DTM). Alguns estudos recentes demonstraram uma relaçãosignificativa entre cefaléia e sinais e sintomas de desordens temporomandibulares, especificamentecom dor miofascial. Quando essa associação ocorre, o tratamento deve ser direcionado para a causado problema (dor miofascial) ou, com certeza, resultará em insucesso e prejuízos para o paciente. Éapresentado o caso clínico da paciente E.P.S., 30 anos, gênero feminino, que compareceu à clínicade Desordens Temporomandibulares da FOAr-UNESP, com queixa principal de dor de cabeça, quese estendia até o pescoço, com intensidade 10 na escala numérica de 1 a 10, freqüência 6x/semanae duração de 2 a 24 horas por dia. Após anamnese e exame físico, foi diagnosticado que a dor decabeça era atribuída a ôtrigger-pointsõ localizados nos músculos temporal e esternoclidomastóideo.Foram apresentados a seqüência clínica de diagnóstico e o tratamento do caso em questão, queenvolveu aconselhamento, fisioterapia, farmacoterapia e injeção nos ôtrigger-pointsõ, com orestabelecimento da qualidade de vida da paciente.

Headaches are symptoms usually reported by patients that suffer of tempomandibulardisorders (TMD). Some recent studies demonstrated a significant relationship between headachesand signs and symptoms of tempomandibular disorders, specifically with myofascial pain.When this association is present, the treatment should be addressed to the cause of the problem(myofascial pain) or it will certainly result in failure and injuries to the patient. It is presented aclinical case report of a female patient, E.P.S., 30 years-old, that presented to the FOARûUNESPTemporomandibular Disorders Clinic, with a chief complaint of headache, that extended to theneck, with an intensity of 10, in a numerical scale ranging from 0-10, frequency of 6 days a week,and duration of 2 to 24 hours a day. After anamnesis and clinical examination it was diagnosed thatthe headache was referred of trigger-points in the temporalis and styernocleidomastoid muscles.We present the complete clinical sequence of diagnosis and treatment of the case, which consistedof counseling, physiotherapy, farmacoteraphy and trigger-points injection, with the recovering ofthe patientÆs quality of life.