58 research outputs found
Composition, Structure, and Formation of Biofilms Constituted by Periodontopathogenic Microorganisms
Microorganisms that compose the oral microbiota maintain complex interactions with each other, especially pathogens related to periodontal disease. It is possible to characterize the etiology of this multifactorial and polymicrobial disease by the accumulation of biofilms formed in the supra- and subgingival environments associated to the immunological response and the susceptibility of the host, being responsible for a large part of the dental loss especially in the adult phase. Periodontal treatment has been carried out mainly by scaling and root planing. This therapy is limited due to the difficult access in some areas of the teeth, impairing the removal of biofilms. So, this chapter will focus on the composition and formation of the biofilm as well as the host’s immune response to periodontopathogenic microorganisms. Additionally, the therapeutic challenges and the treatments that are currently being studied in order to eliminate this biofilm, such as antimicrobial phototherapy, will be discussed
Overall-mouth disinfection by photodynamic therapy using curcumin
Background data: Photodynamic therapy is a technique that involves the activation of photosensitizers by light in the presence of tissue oxygen, resulting in the production of reactive radicals capable of inducing cell death. Objective: The present study assessed the overall susceptibility of pathogens of salivary flora to photodynamic therapy after sensitization with curcumin and exposure to blue light at 450 nm. Methods: A randomized trial was executed with 13 adult volunteers. Three different groups were analyzed: L-D- (no light, no drug; control group), L-D+ (treated only with the drug; curcumin group) and L+D+ (treated with drug and light; photodynamic therapy group). Non-stimulated saliva samples were collected for bacterial counts at baseline and after the experimental phase, and adverse events experienced were recorded. Serial dilutions were performed, and the resulting samples were cultured on blood agar plates in microaerophilic conditions. The number of colony-forming units was then determined. Results: There was a considerable difference between the two experimental groups with regard to effectiveness of bacterial reduction. In the L-D+ group, the bacterial decline was considerably smaller (9%) than in the L+D+ group, with a 68% decrease in bacteria. A statistically significant reduction in the bacterial population was observed only in the photodynamic therapy group (p<0.05). Conclusions: Photodynamic therapy was found to be effective in the reduction of salivary microorganisms. No significant reduction was found for the group in which only curcumin was used, proving the absence of dark toxicity of the drug. This work shows that overall disinfection of the mouth can be done with a simple procedure involving photodynamic action.FAPESPFINEPFACEP
Goodbye Hartmann trial: a prospective, international, multicenter, observational study on the current use of a surgical procedure developed a century ago
Background: Literature suggests colonic resection and primary anastomosis (RPA) instead of Hartmann's procedure (HP) for the treatment of left-sided colonic emergencies. We aim to evaluate the surgical options globally used to treat patients with acute left-sided colonic emergencies and the factors that leading to the choice of treatment, comparing HP and RPA. Methods: This is a prospective, international, multicenter, observational study registered on ClinicalTrials.gov. A total 1215 patients with left-sided colonic emergencies who required surgery were included from 204 centers during the period of March 1, 2020, to May 31, 2020. with a 1-year follow-up. Results: 564 patients (43.1%) were females. The mean age was 65.9 ± 15.6 years. HP was performed in 697 (57.3%) patients and RPA in 384 (31.6%) cases. Complicated acute diverticulitis was the most common cause of left-sided colonic emergencies (40.2%), followed by colorectal malignancy (36.6%). Severe complications (Clavien-Dindo ≥ 3b) were higher in the HP group (P < 0.001). 30-day mortality was higher in HP patients (13.7%), especially in case of bowel perforation and diffused peritonitis. 1-year follow-up showed no differences on ostomy reversal rate between HP and RPA. (P = 0.127). A backward likelihood logistic regression model showed that RPA was preferred in younger patients, having low ASA score (≤ 3), in case of large bowel obstruction, absence of colonic ischemia, longer time from admission to surgery, operating early at the day working hours, by a surgeon who performed more than 50 colorectal resections. Conclusions: After 100 years since the first Hartmann's procedure, HP remains the most common treatment for left-sided colorectal emergencies. Treatment's choice depends on patient characteristics, the time of surgery and the experience of the surgeon. RPA should be considered as the gold standard for surgery, with HP being an exception
Evaluation of the viability of the use of the medium power diode laser in Periodontics: physical and biological aspects
Os lasers de diodo de média potência aparecem como fonte alternativa aos lasers de Nd:YAG e Er:YAG para aplicações em Periodontia, tanto pelo aspecto econômico quanto pela facilidade de utilização, além dos bons resultados obtidos. Neste trabalho, avaliamos o uso do laser de diodo de média potência de até 1.2 W (Diodo FTC 1200, OPTO(r) São Carlos - Brasil) em aplicações periodontais. Para tanto, realizamos primeiramente um mapeamento térmico in vitro, em diferentes espessuras de tecido mole e parâmetros de potência. Este experimento nos revelou que as amostras com espessuras acima de 1.0 mm de tecido mole, não sofrem um aquecimento considerado crítico. Experimentos in vivo em tecido ósseo e mole de ratos também nos permitem afirmar que os parâmetros aqui testados são seguros para aplicações periodontais. O segundo passo deste estudo foi a análise microbiológica in vivo em bolsas periodontais induzidas em ratos. Os exames microbiológicos revelaram a presença de oito microrganismos distintos: Streptococcus beta-hemolitica, Prevotella sp, Fusobacterium sp, Pseudomonas sp, Escherichia coli, Proteus mirabilis, Enterobacter sp, Candida sp. Nossos resultados demonstram uma eficiência do laser de média potência na redução de patógenos periodontais. Especificamente para Prevotella sp e Fusobcterium sp, taxas de redução muito próximas de 100% foram obtidas. Estudos in vitro da ação bactericida do laser, utilizando cepas de Eikenella corrodens (ATCC 23834) e Bacteroides fragilis (ATCC 25285), comprovam sua eficiência. Para finalizar, realizamos a análise histológica dos animais submetidos à irradiação e do grupo controle. As lâminas histológicas confirmam os resultados obtidos pelos testes térmicos, pois nenhuma carbonização, ou alteração irreversível foi notada nos tecidos periodontais. No entanto, restos de alimentos foram evidenciados em algumas das análises histológicas dos ratos que já haviam recebido a irradiação. ) Este fato revela a importância de associar os benefícios proporcionados pela aplicação do laser ao tratamento mecânico de raspagem radicularDiode lasers are modern devices still searching application in dentistry. As an alternative to be applied in periodontal treatment, diode laser can substitute the conventional solid state lasers like Nd:YAG and Er:YAG with tremendous advantage in cost and facility of use. This work has the aim to demonstrate the use of medium power diode laser in the treatment of periodontal disease. For this purpose a sequence of experiments were carried out using (Diodo FTC 1200, OPTO® São Carlos − Brasil). First we investigated the thermal effect on the adjacent tissue when the laser is used having the periodontal chamber as a target. Second, using an animal model we explored the efficiency of bacteria elimination when diode laser is used. Several types of bacterias as Streptococcus betahemolitica, Prevotella sp, Fusobacterium sp, Pseudomonas sp, Escherichia coli, Proteus mirabilis, Enterobacter sp, Candida sp were investigated. In a final observation, the histological exam was performed. A good preservation as well as evidence of strange bodies were observed. In conclusion we established that diode lasers are an appropriate tool for periodontal car
Evaluation of the viability of the use of the medium power diode laser in Periodontics: physical and biological aspects
Os lasers de diodo de média potência aparecem como fonte alternativa aos lasers de Nd:YAG e Er:YAG para aplicações em Periodontia, tanto pelo aspecto econômico quanto pela facilidade de utilização, além dos bons resultados obtidos. Neste trabalho, avaliamos o uso do laser de diodo de média potência de até 1.2 W (Diodo FTC 1200, OPTO(r) São Carlos - Brasil) em aplicações periodontais. Para tanto, realizamos primeiramente um mapeamento térmico in vitro, em diferentes espessuras de tecido mole e parâmetros de potência. Este experimento nos revelou que as amostras com espessuras acima de 1.0 mm de tecido mole, não sofrem um aquecimento considerado crítico. Experimentos in vivo em tecido ósseo e mole de ratos também nos permitem afirmar que os parâmetros aqui testados são seguros para aplicações periodontais. O segundo passo deste estudo foi a análise microbiológica in vivo em bolsas periodontais induzidas em ratos. Os exames microbiológicos revelaram a presença de oito microrganismos distintos: Streptococcus beta-hemolitica, Prevotella sp, Fusobacterium sp, Pseudomonas sp, Escherichia coli, Proteus mirabilis, Enterobacter sp, Candida sp. Nossos resultados demonstram uma eficiência do laser de média potência na redução de patógenos periodontais. Especificamente para Prevotella sp e Fusobcterium sp, taxas de redução muito próximas de 100% foram obtidas. Estudos in vitro da ação bactericida do laser, utilizando cepas de Eikenella corrodens (ATCC 23834) e Bacteroides fragilis (ATCC 25285), comprovam sua eficiência. Para finalizar, realizamos a análise histológica dos animais submetidos à irradiação e do grupo controle. As lâminas histológicas confirmam os resultados obtidos pelos testes térmicos, pois nenhuma carbonização, ou alteração irreversível foi notada nos tecidos periodontais. No entanto, restos de alimentos foram evidenciados em algumas das análises histológicas dos ratos que já haviam recebido a irradiação. ) Este fato revela a importância de associar os benefícios proporcionados pela aplicação do laser ao tratamento mecânico de raspagem radicularDiode lasers are modern devices still searching application in dentistry. As an alternative to be applied in periodontal treatment, diode laser can substitute the conventional solid state lasers like Nd:YAG and Er:YAG with tremendous advantage in cost and facility of use. This work has the aim to demonstrate the use of medium power diode laser in the treatment of periodontal disease. For this purpose a sequence of experiments were carried out using (Diodo FTC 1200, OPTO® São Carlos − Brasil). First we investigated the thermal effect on the adjacent tissue when the laser is used having the periodontal chamber as a target. Second, using an animal model we explored the efficiency of bacteria elimination when diode laser is used. Several types of bacterias as Streptococcus betahemolitica, Prevotella sp, Fusobacterium sp, Pseudomonas sp, Escherichia coli, Proteus mirabilis, Enterobacter sp, Candida sp were investigated. In a final observation, the histological exam was performed. A good preservation as well as evidence of strange bodies were observed. In conclusion we established that diode lasers are an appropriate tool for periodontal car
Low-level laser therapy in pediatric Bell's palsy: case report in a three-year-old child
Objectives: The objective of this study was to apply low-level laser therapy (LLLT) to accelerate the recovery process of a child patient with Bell's palsy (BP). Design: This was a prospective study. Subject: The subject was a three-year-old boy with a sudden onset of facial asymmetry due to an unknown cause. Materials and methods: The low-level laser source used was a gallium aluminum arsenide semiconductor diode laser device (660nm and 780 nm). No steroids or other medications were given to the child. The laser beam with a 0.04-cm2 spot area, and an aperture with approximately 1-mm diameter, was applied in a continuous emission mode in direct contact with the facial area. The duration of a laser session was between 15 and 30 minutes, depending on the chosen points and the area being treated. Light was applied 10 seconds per point on a maximum number of 80 points, when the entire affected (right) side of the face was irradiated, based on the small laser beam spot size. According to the acupuncture literature, this treatment could also be carried out using 10-20 Chinese acupuncture points, located unilaterally on the face. In this case study, more points were used because the entire affected side of the face (a large area) was irradiated instead of using acupuncture points. Outcome measures: The House-Brackmann grading system was used to monitor the evolution of facial nerve motor function. Photographs were taken after every session, always using the same camera and the same magnitude. The three-year-old boy recovered completely from BP after 11 sessions of LLLT. There were 4 sessions a week for the first 2 weeks, and the total treatment time was 3 weeks. Results: The result of this study was the improvement of facial movement and facial symmetry, with complete reestablishment to normality. Conclusions: LLLT may be an alternative to speed up facial normality in pediatric BP.FAPESPCePOFCNP
A 12-month follow-up of hypopigmentation after laser hair removal
Introduction: Laser hair removal is becoming an increasingly popular alternative to traditional methods such as shaving, waxing, among other methods. Semiconductor diode lasers are considered the most efficient light sources available and are especially well suited for clinical applications including hair reduction. The effectiveness of laser hair reduction depends on many variables, including the skin type of the patient. Material and Methods: A patient with Fitzpatrick Skin Type IV was submitted to laser hair removal of the arms with a high-power diode laser system with long pulses with a wavelength of 800 nm, a fluence of 40 J/cm2 and a pulse width of 20 ms. A 12-month follow-up assessment was performed and included photography and questionnaire. Results: Hypopigmentation was observed after a single laser hair removal section. After 6 months with the area totally covered, a gradual suntan with a sun screen lotion with an SPF of 15 was prescribed by the dermatologist. After 12 months of the initial treatment, a complete recovery of the hypopigmentation was achieved. Conclusion: Although a safe procedure, lasers for hair removal may be associated with adverse side effects including undesired pigment alterations. Before starting a laser hair removal treatment, patients seeking the eradication of hair should be informed that temporary, and possibly permanent, pigmentary changes may occur
Synergistic effect of photodynamic therapy and cisplatin: a novel approach for cervical cancer
Cervical cancer is a neoplasia primarily caused by Human papillomavirus (HPV) infection. Current treatment modalities involve cisplatin, a potent chemotherapeutic agent with severe adverse effects. Photodynamic therapy (PDT) is a promising modality for the treatment of cancer and infections, which has been associated with innovative therapeutic approaches, especially for the treatment of neoplasias. This study aimed to investigate the anticancer potential of PDT mediated by methylene blue (MB) or Photogem (PG) individually and combined with cisplatin in vitro. SiHa, C-33 A and HaCaT cells were incubated with MB, PG and/or cisplatin and received no further treatment or were irradiated with a 630 or a 660 nm LED light source at energy densities varying according to the photosensitizer (PS). The MTT assay was employed to assess cell viability. Both PS were effective in reducing cell viability with the cytotoxicity being dependent on the light dose. When compared to PDT groups, cisplatin was less effective. The cell viability of the combined therapy groups was significantly lower compared to monotherapies. The sequence of treatments (PDT + cisplatin/cisplatin + PDT) was important and had different results when varying the PS, but combination therapy resulted in an enhanced anticancer effect regardless of treatment protocol. (C) 2014 Elsevier B.V. All rights reserved.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP
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