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

Comparison of subgingival plaque removal using hand curettes, magnetostrictive ultrasonic sealers and air polishing devices with and without nacho[3] abrasive powder: an ex vivo study

One important treatment objective of periodontal therapy is the removal of bacterial deposits and the arrest of disease progression. The aim of the present study was to compare subgingival plaque removal using hand curettes, magnetostrictive ultrasonic sealers and air-polishing devices [APD] with and without NaHCO3 abrasive powder. In this controlled randomized clinical trial, all surfaces of 60 single-rooted hopeless teeth with untreated periodontitis were treated either by hand curettes, magnetostrictive ultrasonic sealers or APD with or without NaHCO[3] abrasive powder. The teeth were extracted and stained in methylene blue in water solution. Digital images were captured under a microscope and depth of plaque removal was measured with image processing software. ANOVA and correlation tests were applied to data. The mean comparison showed that using APD with water alone failed to achieve adequate plaque removal. Subgingival plaque removal in the lingual surface was significantly lower in all investigated instruments [P < 0.001]. The mean cleansing depths of curettes, ultrasonic sealers and APD with NaHCO[3] powder were 4.6, 6.0 and 4.2 mm, respectively. The effectiveness of different instruments is not identical for different sites. Therefore, the efficiency of these instruments should be adjusted for various clinical applications