Isolation, pathogenicity and disinfection of Staphylococcus aureus carried by insects in two public hospitals of Vitória da Conquista, Bahia, Brazil

Currently, hospital infection is a serious public health problem, and several factors may influence the occurrence of these infections, including the presence of insects, which are carriers of multidrug-resistant bacterial species. The aim of this study was to isolate staphylococci carried by insects in two public hospitals of Vitoria da Conquista, Bahia and to identify the resistance profile, pathogenicity and efficacy of disinfection of the premises. A total of 91 insects were collected in 21 strategic points of these hospitals, and 32 isolated strains ofStaphylococcus aureus were isolated. Based on antibiogram and Minimum Inhibitory Concentration results, 95% of these strains were susceptible to oxacillin. These strains were also evaluated for the presence of resistance genes encoding resistance to oxacillin/methicillin by polymerase chain reaction, but the sample was negative for this gene. Pathogenicity tests were performed in vitro biofilm formation induced by glucose, where it was found that eight (27.58%) strains were classified as biofilm producers and 21 (72.4%) as stronger producers. In addition, we performed PCR for their virulence genes: Sea (enterotoxin A), SEB (B), Sec (C), PVL (Panton-Valentine Leukocidin), ClfA (clumping factor A) and Spa (protein A). Of these, Sea, Spa PVL were positive in 7 (21.8%), 2 (6.3%) and 1 (3.1%) samples, respectively. The analysis of cytokine induction in the inflammatory response of J774 macrophages by isolates from the two hospitals did not show statistical difference at the levels of IL-6, TNF-α, IL-1 and IL-10 production. In addition, we verified the antimicrobial activity of disinfecting agents on these strains, quaternary ammonium, 0.5% sodium hypochlorite, 1% sodium hypochlorite, 2% sodium hypochlorite, 2% glutaraldehyde, Lysoform®, 70% alcohol solution of chlorhexidine digluconate, 2% peracetic acid, and 100% vinegar. Resistance was seen in only for the following two disinfectants: 70% alcohol in 31 (96.8%) samples tested and vinegar in 30 (93.8%) samples. The study demonstrated the presence of resistant and pathogenic organisms conveyed by insects, thus suggesting improvement in efforts to control these vectors.

Influence of retentive areas associated to onlay preparations on the dimensional stability of silicone impression materials

This study evaluated the effect of retentive areas on onlay preparations on the dimensional alterations in condensation and addition silicone materials. A standard model with an onlay preparation was made. Each impression material was used through the double or simultaneous impression technique (n=25), resulting in a hundred impressions of the same model. Impressions were poured with type IV dental stone. Digital images were taken with a light microscope and the distances between the reference points created on the plaster dies were compared with the ones on the standard model. In the occlusal, mesial-medium and mesial-cervical segments, the double impression (DI) with condensation silicone presented similar values compared to the standard model. The values of the addition silicone with DI were similar to the standard model only in the mesial-occlusal segment. In the other segments (distal-cervical, distal-medium and distal-occlusal), all groups were statistically different from the control. It could be concluded that addition and condensation silicone impressions provided plaster dies with significant dimensional alterations in most of the evaluated areas when compared to the standard model. The retentive areas related to the onlay preparation influenced the dimensional stability of the addition and condensation silicone impressions.

Este estudo avaliou as alteracoes dimensionais de silicones de condensacao e adicao usados em duas tecnicas como resultado de areas retentivas de preparos do tipo onlay. Um modelo padrao foi feito e vinte e cinco moldagens realizadas com os dois materiais, atraves da tecnica de dupla impressao ou impressao simultanea, e cada material resultou em 50 modelos de gesso. Imagens digitais foram feitas com um microscopio de luz e as distancias entre os pontos de referencia criados no modelo de gesso foram comparados aos pontos de referencia no modelo padrao. Nos segmentos oclusais, medio-mesial e cervico-mesial, a tecnica de dupla impressao (DI) com silicone de condensacao apresentou valores similares comparados ao modelo padrao. Os valores do silicone de adicao com DI foram similares ao modelo padrao somente no segmento mesio-oclusal. Nos outros segmentos (disto-cervical, medio-distal e disto-oclusal), todos os grupos foram estatisticamente diferentes do controle. Pode- se concluir que moldagens com silicone de adicao e condensacao conferem modelos de gesso com alteracoes dimensionais significativas na maioria das areas avaliadas, quando comparadas ao modelo padrao. As areas retentivas relacionadas ao preparo de onlay influenciaram na estabilidade dimensional das moldagens atraves dos silicones de condensacao e adicao.

Sedação consciente com benzodiazepínicos em odontologia / Conscious sedation with benzodiazepines in dentistry

A ansiedade e o medo são fatores de fuga ao tratamento odontológico. O controle da ansiedade pode ser obtido por meios farmacológicos e não- farmacológicos. Dentre os não-farmacológicos, o uso de benzodiazepínicos, por via oral, constitui uma boa alternativa para se obter a sedação consciente, em Odontologia, por apresentar uma ampla margem de segurança clínica, rápido início de ação, pequena incidência de reações adversas, facilidade de administração e baixo custo. Assim, esta revisão tem por objetivo investigar as características farmacológicas, critérios de escolha e regimes posológicos dos benzodiazepínicos de maior interesse para o cirurgião-dentista. O diazepam, lorazepam, alprazolam, midazolam e triazolam são as drogas mais empregadas na sedação de pacientes odontológicos. O lorazepam é mais indicado para idosos, pela menor incidência de efeitos paradoxais. Quando se deseja uma sedação mais prolongada, o diazepam é a droga de escolha. Ao contrário, por apresentar início de ação mais rápido e duração mais curta, além de induzir amnésia anterógrada, o midazolam é a droga mais indicada nas urgências odontológicas e na sedação consciente de pacientes pediátricos.

Fear and anxiety are factors of avoidance of dental treatment. The anxiety control can be obtained by pharmacologic and non-pharmacologic methods. Among the pharmacologic methods, oral benzodiazepines is a good choice to obtain conscious sedation in dentistry, as they present a wide therapeutic index, fast onset, little incidence of adverse reactions and low cost. The aim of this review was to assess benzodiazepines used in dentistry as to their pharmacologic characteristics, regimens and choice criteria. The most used benzodiazepines in oral conscious sedation are diazepam, lorazepam, alprazolam, midazolam and triazolam. Lorazepam is the preferable drug in the elderly due to its lower tendency to cause paradoxal effects. When prolonged sedation is desired, diazepam is the drug of choice. On the contrary, by presenting fast onset and short duration of action, midazolam is the most indicated benzodiazepine for dental emergencies and oral conscious sedation in pediatric patients.