Mikroleakage-Untersuchung von Wurzelkanalfüllungen nach unterschiedlichen medikamentösen Einlagen:zwei neue Wurzelkanalsealer im Vergleich zum Standard AH Plus

Summary Objectives The objective of a successful root treatment is to establish a permanent, bac-teria- and fluid-proof obturation of the root-canal system. During a root-canal treatment the usage of intracanal medicaments can be necessary. Their remnants bear a potential risk to deteriorate the sealing characteristics of the root-canal filling. Thus, the present study examined the influence of different medical guttapercha-points on the sealing ability of GuttaFlow (GF) and Epiphany (EP) in comparison to the established sealer AH Plus (AH). Materials and Methods 90 single-rooted teeth were divided into 3 groups (n=30) according the above mentioned sealers, which were further divided into 3 subgroups (n=10) each, assigned to different medical dressings (Chlorhexidine-diacetate: CHX, Calcium hydroxide: CaOH, no dressing: (-)).Root canals were prepared by crown-down technique to a size 45, taper .04. Subsequent cleaning was done with an activated solution of sodium hypochlorite (5%), citric acid solution (40%) and a final rinse with ethanol (70%). The teeth were then prepared with the specific medical dressing, sealed off with a foam pellett and Cavit and stored in an incubator (37°C/100% humidity) for 7 days. Afterwards a final irrigation cycle of same routine was performed, followed by the root-canal filling with the corresponding sealer, using a single-cone-technique. After an incubation of 7 more days all teeth were sealed off with two layers of nail lacquer. The apical tip of the root was cut off with a diamond blade. All teeth were centrifuged (30g) for 3 minutes in methylene blue (5%). Teeth of all test groups were fixated in PU resin and cut into 1mm layers. Dye penetration was determined using optical microscope at 25x magnification. Results Both factors “sealers” and “intracanal medicament” showed a significant in-fluence on penetration depths (Two-Way-ANOVA, ≤ 0,05). In detail following average depths (mm) were observed: H/-: 4.80, AH/CaOH: 6.73, AH/CHX: 2.73, GF/-: 4.46, GF/CaOH: 3.06, GF/CHX: .86, EP/-: 4.86, EP/CaOH: 3.3, EP/CHX: 1.93. While CHX improved sealing ability of all sealers, CaOH re-sulted in different effects: A slight improvement according EP and GF, and a performance decline while applying AH. Conclusions The present study showed that medicinal dressings also have a significant influence on the obturation properties of root-canal fillin pointgs, when they are applied in form of an active gutta-percha. CHX was always observed having a positive effect. Only the dressing of a Ca(OH)2 point prior to an AH Plus filling has to be considered as critical.