Effect of synthetic tissue fluid on microleakage of grey and white mineral trioxide aggregate as root-end filling materials

The success of endodontic surgery has been shown to depend partly on the apical seal. Grey mineral trioxide aggregate [GMTA] produces hydroxyapatite twice as often as white mineral trioxide aggregate [WMTA] when suspended in a phosphate buffered saline [PBS] solution. The aim of this in vitro study was to compare the microleakage phenomenon of gray and white mineral trioxide aggregates as root-end filling materials after immersion in synthetic tissue fluid [STF]. 55 single-rooted extracted maxillary anterior human teeth were divided into two experimental groups of 20 teeth each, plus 3 groups of 5 teeth each as two negative and one positive control groups. The root canals were cleaned, shaped, and laterally compacted with gutta-percha. The root ends were resected and 3 mm deep cavities were prepared. The root-end preparations were filled with GMTA or WMTA in the experimental groups. Leakage was determined using a dye penetration method. Data were analysed using analysis of variance [ANOVA] at the 0.05 level of significance. Results: The mean dye leakage was 0.40 +/- 0.1 mm for GMTA and 0.50 +/- 0.1 mm for WMTA groups, respectively. There was no significant difference between the two experimental groups [P = 0.14]. Despite the different properties and behaviours of GMTA and WMTA in STF, there were no significant differences in microleakage when using GMTA or WMTA

Microleakage comparison of four dental materials as intra-orifice barriers in endodontically treated teeth

The aim of this in vitro study was to compare polymicrobial microleakage of calcium enriched mixture [CEM] cement, mineral trioxide aggregate [MTA], amalgam, and composite resin as intra-orifice sealing materials. Seventy single-rooted mandibular premolars were instrumented and obturated by cold lateral compaction technique. The teeth were randomly divided into four experimental groups according to used material: CEM, MTA, amalgam and composite resin [n=15] and two control groups [n=5]. In experimental groups, 2 mm of coronal gutta-percha was removed and replaced with the study material. All the teeth were mounted in a two-chamber apparatus and the coronal portion was exposed to human saliva. The day the turbidity occurred was recorded for each sample. Data were analyzed using one-way ANOVA. The negative control group showed no leakage while the average microleakage time in the positive control group was 3.5 days. The average bacterial leakage times for amalgam, composite resin, MTA, and CEM groups were 27.42 +/- 3.6, 29.35 +/- 3.15, 52.57 +/- 2.87, and 50.42 +/- 2.73 days, respectively. There was no significant difference between CEM and MTA groups [P=0.27] and also between amalgam and composite resin groups [P=0.36]. However, in term of average leakage time, MTA and CEM groups exhibited significant differences with amalgam and composite resin groups [P<0.001]. According to the results of the present in vitro study, in terms of coronal sealing in endodontically treated teeth, CEM and MTA are more effective than amalgam and composite resin

In vitro comparison of dye penetration through four temporary restorative materials

The purpose of this in vitro study was to compare the coronal seal of four temporary filling materials, Coltosol, Zonalin, Zamherir, and Intermediate Restorative Material [IRM] by the India ink dye penetration test. Endodontic access preparations were prepared in 120 extracted intact human premolars. The teeth were randomly divided into six groups including four experimental and two control groups. The access cavities in each group were sealed with Coltosol, Zonalin, Zamherir, and IRM; subsequently thermocycling was applied for 5-55°C for 150 cycles. The teeth were immersed in 10% India ink for 72 hours to assess leakage. The teeth were then rinsed, dried, and sectioned mesiodistally and evaluated under a stereomicroscope for dye penetration. Data were analyzed using one-way ANOVA and post hoc Tukey tests. Positive control specimens showed complete dye penetration, while negative controls had no penetration. In the experimental groups, the lowest and highest leakage scores were observed in the Zonalin and Coltosol groups, respectively [P<0.05]. There were no statistically significant differences in marginal leakage between Zonalin-Zamherir and Coltosol-IRM groups. These results suggest that Zonalin and Zamherir have a superior seal and less micro-leakage into the canals compared to the two other materials