5 research outputs found
Lipopolysaccharide and its threatening zombie-like nature: unlive, harmful and tough (but not impossible) to eliminate
Radiopacity evaluation of Portland and MTA-based cements by digital radiographic system
OBJECTIVE: The aim of the present study was to evaluate the radiopacity of Portland and MTA-based cements using the Digora TM digital radiographic system. MATERIAL AND METHODS: The performed tests followed specification number 57 from the American National Standard Institute/American Dental Association (2000) for endodontic sealing materials. The materials were placed in 5 acrylic plates, especially designed for this experiment, along with a graduated aluminum stepwedge varying from 1 to 10 mm in thickness. The set was radiographed at a 30 cm focus-object distance and with 0.2 s exposure time. After the radiographs were taken, the optical laser readings of radiographs were performed by Digora TM system. Five radiographic density readings were performed for each studied material and for each step of the aluminum scale. RESULTS: White ProRoot MTA (155.99±8.04), gray ProRoot MTA (155.96±16.30) and MTA BIO (143.13±16.94) presented higher radiopacity values (p<0.05), while white non-structural Portland (119.76±22.34), gray Portland (109.71±4.90) and white structural Portland (99.59±12.88) presented lower radiopacity values (p<0.05). CONCLUSIONS: It was concluded that MTA-based cements were the only materials presenting radiopacity within the ANSI/ADA specifications
Evaluation of the radiopacity of root canal sealers by digitization of radiographic images Avaliação da radiopacidade de cimentos endodônticos por meio da digitalização de imagens radiográficas
The aim of this study was to evaluate the radiopacity of a zinc oxide and eugenol-based (Endofill), a calcium hydroxide-based (Sealapex), two resin-based (Sealer 26 and AH Plus), and a silicone-based root canal sealer (Roeko Seal). Specimens, measuring 10mm in diameter and 1mm in thickness, were radiographed simultaneously with an aluminum step wedge using occlusal films, according to ISO 6876/2001 standards. Radiographs were digitized, and the radiopacity of sealers was compared to the different thicknesses of the aluminum step wedge, using the VIXWIN 2000 software. Results demonstrated that AH Plus was the most radiopaque sealer, while Sealapex was the least radiopaque (p<0.05). Roeko Seal, Endofill and Sealer 26 presented intermediate radiopacity values. Sealapex presented less radiopacity than the other types of root canal sealers.<br>O objetivo deste trabalho foi avaliar a radiopacidade de cimentos endodônticos à base de óxido de zinco e eugenol (Endofill), hidróxido de cálcio (Sealapex), resina (Sealer 26 e AH Plus) e silicone (Roeko Seal). Os corpos de prova foram padronizados com 10 milímetros de diâmetro e 1 milímetro de espessura e radiografados conjuntamente com uma escala de alumínio empregando-se filmes oclusais, de acordo com as Normas ISO 6876/2001. As radiografias foram digitalizadas e as radiopacidades dos cimentos comparadas à escala de alumínio com diferentes espessuras, utilizando o software VIXWIN 2000. Os resultados demonstraram que o AH Plus foi o cimento mais radiopaco e o Sealapex apresentou menor radiopacidade (p<0,05), sendo intermediários os resultados para os cimentos Roeko Seal, Endofill e Sealer 26. Sealapex apresenta menor radiopacidade que outros tipos de cimentos endodônticos
