Avaliação do sistema WaveOne Gold e ProTaper retratamento para remoção de guta-percha clínico / Evaluation of WaveOne Gold system and ProTaper retreatment for gutta-percha removal

Objetivo: avaliar ex vivo a quantidade de guta-percha remanescente no retratamento de canal de dentes pré-molares inferiores com único canal utilizando o sistema WaveOne Gold em comparação com o sistema de retratamento ProTaper R. Materiais e métodos: foram selecionados 52 pré-molares inferiores humanos extraídos, distribuídos aleatoriamente em 2 grupos (n=26), em função das técnicas de retratamento: sistema WaveOne Gold (grupo 1) e sistema de retratamento ProTaper R (grupo 2). Após os canais radiculares serem instrumentados e obturados com guta--percha, foram submetidos à de sobturação e ao procedimento de retratamento. Os dentes foram seccionados confeccionando uma canaleta nas faces proximais dos dentes obtendo-se duas hemi--secções radiculares, expondo, portanto, a luz do canal preparado. Todas as amostras foram codificada se fotografadas por máquina Cânon A640 acoplada ao microscópio Zeiss, com aumento de 5 vezes. As fotos foram transportadas para o programa de software Image Tool 3.0. Foi feita medição das áreas de remanescentes de material obturador no interior do canal e a medição da área total do interior do canal através das imagens da secção no computador. As medidas foram comparadas em relação a cada sistema utilizando o programa BioEstat 4.0 (teste de Mann-Whitney). Resultados:A menor porcentagem de material obturador remanescente ocorreu no sistema ProTaper Rcom diferenças significantes em relação ao sistema WaveOne Gold (p<0.01). Conclusão: o sistemaProTaper R foi mais eficaz na remoção de guta-percha em comparação com o sistema WaveOne Gold, entretanto nenhum dos sistemas removeram totalmente o material obturador do canal.

Objective: This ex vivo research study aims to evaluate ex vivo the amount of remaining gutta -perchaduring canal retreatment of lower premolars single-rooted using WaveOne Gold system compared with Protaper R system. Materials and methods: 52 mandibular premolars were selected and randoml y divided into 2 groups (n = 26), according to the retreatment techniques, which are: WaveOne Gold system(group 1) and ProTaper R system (group 2). After the root canals were instrumented and filled withgutta-percha, they underwent removal procedure. After retreatment procedure, the teeth were sectioned in the proximal surfaces resulting in two hemi-sections exposing the interior of the root canal. Allsamples were coded and photographed by A640 Canon machine attached to the microscope Zeiss withzoom in 5 times, and the photos were transported to the Image Tool 3.0. software. The evaluation wasdone by measurement of areas of remaining filling material and the total area of the interior of root canal through the images on the computer. The measurements were compared for each system using Bio-Estat 4.0 program and Mann-Whitney test. Results: The smallest percentage of remaining gutta-perchaoccurred in ProTaper Retreatment system with significant differences from the WaveOne Gold system(p <0.01).Conclusion: ProTaper R system was more effective in removing gutta-percha compared withWaveOne Gold system. However none of the both systems completely removed the filling material.

An experimental study on maximum sound output capabilities and preferred listening levels using different earphone types

@#<p style="text-align: justify;"><strong>OBJECTIVE:</strong> The  study  aims  to  compare  the  maximum  sound  output  capabilities  of  different earphone types/music style combinations. The study also intends to assess the preferred listening levels (PLL) of test subjects using different earphone types with background noise accession. The study also seeks to determine the presence or absence of a threshold shift on headphone/music style combination PLLs that exceed the recommended noise limit.<br /><strong>METHODS:</strong><br /><strong>Design:</strong> Experimental Study<br /><strong>Setting:</strong> Tertiary Government Hospital<br /><strong>Subjects:</strong> Thirty (30) hearing healthy volunteers were sampled from hospital staff aged 18-40 years with no known history of ear pathology and/or use of any known ototoxic drugs, with normal otoscopy, audiograms of less than 20dB from 125Hz to 8000Hz and no exposure to loud noise from any source within the previous three days.The sound pressure levels (SPL) delivered by three (3) types of earphones (earbud type, in-ear  type,  supra-aural  type)  were  measured  at  maximum  volume  setting  of  a  personal  media player  (iPod,  Apple  Inc.),  while  playing  different  music  genres. The  test subjects  were  asked  to listen at their preferred listening levels (PLL) using the different types of earphones at increasing background noise accession.<br /><strong>RESULTS:</strong> The  earbud  type  averaged  the  greatest  SPL  among  the  earphone  types  and  pop music averaged the greatest SPL among the music styles. Comparison of the maximum output capabilities revealed that there was a significant difference among different brands of earphones of the same type. However, no significant difference were found among songs of similar music style and across different music styles in all earphones except the in-ear type. PLL average was at  90.4dB  in  a  silent  environment  with  increasing  intensity  as  background  noise accentuated. Supra-aural earphones registered the least increase in PLL in a loud environment due to its higher background noise-attenuating capabilities.<br /><strong>CONCLUSION:</strong> Having a significant difference among earphone types with regard their maximum output  capabilities,  it  is  recommended  to  check  the  specifications  of  the  earphone  type  one intends  to  use.  In  using  personal  media  players  (PMP),  the  volume  should  be  set  at  the  lowest comfortable  level. While  choice  of  music  style  remains  the  discretion  of  the  listener,  the  choice of  music  style  should  be considered  for  long  periods  of  listening.  Because  the  PLL  of  test subjects  were  alarmingly  high,  the  authors  recommend  intervention in  their  listening  habits.  Background  noise  attenuating  capabilities of earphones  play  a  factor  in  reducing  excessive  sound  energy  from reaching  the  ear  reducing  the  PLL  and  decreasing  the  risk  for  noise-induced hearing loss.</p>

Visceral leishmaniasis in Teresina, state of Piauí, Brazil: preliminary observations on the detection and transmissibility of canine and sandfly infections

A Leishmania donovani-complex specific DNA probe was usedto confirm the widespread dissemination of amastigotes in apparently normal skinof dogs with canine visceral leishmaniasis. When Lutzomyia longipalpis were fed on abnormal skin of five naturally infected dogs 57 of 163 (35 per cent) fliesbecame infected: four of 65 flies (6 per cent) became infected when fed on apparently normal skin. The bite of a single sandfly that had fed seven days previouslyon a naturally infected dog transmitted the infection to a young dog from a non-endemic area. Within 22 days a lesion had developed at the site of the infectivebite (inner ear): 98 days after infection organisms had not disseminated throughout the skin, bone marrow, spleen or liver and the animal was still serologically negative by indirect immunofluorescence and dot-enzyme-linked immunosorbent assay. When fed Lu. longipalpis were captured from a kennel with a sick dog known to be infected, 33 out of 49 (67 per cent) of flies contained promastigotes. In contrast only two infections were detected among more than 200 sandflies captured in houses. These observations confirm the ease of transmissibility of L.chagasi from dog to sandfly to dog in Teresina. It is likely that canine VL is the major source of human VL by the transmission route dog-sandfly-human. the Lmet2 DNA probe was a useful epidemiological tool for detecting L. chagasi in sandflies

Improving trauma care in Trinidad and Tobago

Indentification of trauma as a major cause of morbidity and mortality in Trinidad and Tobago prompted the establishment of a training programme aimed at improving trauma care in this developing country. An Advanced Trauma Life Support (ATLS) programme for physicians, funded through the Canadian International Development Agency resulted in a statistically significant improvement of in-hospital trauma patient outcome at the Port-of-Spain General Hospital (observed to expected mortality ratio of 3.16 pre-ATLS compared to 1.94 post ATLS). A recent analysis of all motor vehicle injuries for a shorter period did not confirm this positive impact of the ATLS programme, primarily because a large number of these patients died in the pre-hospital period. Pre-hospital trauma care therefore required urgent attention to complement the positive in-hospital impact of the ATLS programme. A second training programme (the Pre-Hospital Trauma Life Support or PHTLS) for paramedical personnel was thus instituted in 1990. Over 250 physicians have been trained in the ATLS programme and to date over 100 paramedical personnel have been trained in the PHTLS programme. Attempts have also been made to equip the ambulances with more appropriate resuscitative devices in order to improve pre-hospital care. The combination of the PHTLS and the ATLS programme should result in further improvement in the care of patients sustaining major injuries in Trinidad and Tobago.