title: In vitro sealing ability of white and gray mineral trioxide aggregate (MTA) and white Portland cement used as apical plugs.
abstract: This study evaluated the sealing ability of apical plugs made of white and gray MTA-Angelus and white Portland cement placed via the root canal and having different thicknesses (2, 5 and 7 mm). Ninety extracted human single-rooted teeth were instrumented using a size 40 K-file to standardize the foraminal opening by the stepback technique. The teeth were assigned to 3 groups (n=30), according to the material used for fabrication of the apical plugs: A = gray MTA; B = white MTA; C = white Portland cement. The groups were subdivided into groups of 10 teeth each according to the apical plug thickness (2, 5 and 7 mm). Marginal apical dye leakage was assessed using 0.2% Rhodamine B solution in which the specimens were immersed for 72 hours at 37 degrees C. The roots were sectioned longitudinally in a buccolingual direction for apical plug exposure, and digital photographs were taken and analyzed by Image Tool image-analysis software. Data were analyzed statistically by Kruskal-Wallis and Dunn's tests. Significance level was set at 5%. The least percent leakage was observed for 5- and 7-mm-thick plugs (p<0.05). No significant difference (p>0.05) was found between gray MTA and white Portland cement. Among the three materials analyzed, white MTA presented the highest marginal leakage (p<0.05). The findings of the present study showed that gray MTA and Portland cement had better sealing ability than white MTA when used as apical plugs. Dye leakage was smaller for 5- and 7-mm-thick plugs compared to 2-mm-thick plugs.
authors.affiliation: Bauru School of Dentistry, University of São Paulo, Bauru, SP, Brazil. pzaconeglian@terra.com.br
authors.forename: Patrícia Zanatta Aranha
authors.initials: PZ
authors.lastname: Coneglian
authors.forename: Fernando Accorsi
authors.initials: FA
authors.lastname: Orosco
authors.forename: Clóvis Monteiro
authors.initials: CM
authors.lastname: Bramante
authors.forename: Ivaldo Gomes
authors.initials: IG
authors.lastname: de Moraes
authors.forename: Roberto Brandão
authors.initials: RB
authors.lastname: Garcia
authors.forename: Norberti
authors.initials: N
authors.lastname: Bernardineli