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

Endodontic treatment of a hypertaurodont mandibular second molar: a case report

A 28-year old patient was referred for endodontic treatment of his left mandibular second molar. The patient had no history of systemic diseases and his chief complaint was spontaneous pain in left posterior region of mandible. Clinically, there was a deep caries in the left mandibular second molar. Radiographic examination of this tooth revealed a long crown containing large pulp chamber and two short roots with a apically located furcation, indicating hypertaurodontism. After coronal access preparation, five orifices were found including mesiolingual, mesiobuccal, distobuccal, mid-distal and distolingual. Subsequent to root canal preparation, a modified filling technique was used for canal obturation. After one year the treated tooth was symptom free

Mandibular second premolars with three root canals: a review and 3 case reports

Before initiating any endodontic therapy, probability of extra canals should be considered. The Incidence of three canals in mandibular second premolar has been reported to be 0.46-0.5%. The present report describes nonsurgical endodontic treatment of three mandibular second premolars with three canals. In these cases, three orifices were located in mesiobuccal, distobuccal and lingual. Mesiobuccal orifices were found after removing dentinal shelves. Even in teeth with extremely complex root canal morphologies, conventional endodontic treatment without surgical intervention can result in adequate healing, as in these cases. Clinicians should be aware of unusual root canal anatomy in mandibular premolars. Very careful examination of the pulpal space, preferably with an optical device is recommended to locate any unusual orifices

comparative scanning electron microscope investigation of cleanliness of root canals using hand K-Flexofiles, rotary RaCe and K3 instruments

The most important aims of root canal preparation are the removal of vital pulp tissue, remaining necrotic debris and infected dentin, eliminating the bulk of bacteria present in the root canal system. The aim of this study was to compare the cleaning efficacy of hand K-Flexofiles and rotary RaCe and K3 instruments in root canal preparation. A total of 60 single rooted teeth with maximum curvature of <20§ were selected and divided into three groups of 20 teeth each. Canals were prepared with KFlexofiles, K3 and RaCe instruments using crown down preparation technique, up to size #30. After instrumentation, the root canals were flushed with 5 mL of 2.5% NaOCl solution. The amount of debris and smear layer was quantified on the basis of Hulsmann method using a scanning electron microscope. The data were statistically analyzed with one-way ANOVA test at a significance level of P<0.05. None of the three groups achieved completely debrided root canals.. In general, KFlexofiles were able to achieve cleaner canals compared to K3 and RaCe instruments [P<0.05]. There were no significant differences between three groups in smear layer removal throughout the root canal walls [P<0.05]. K-Flexofiles group had less remained debris when compared to K3 and RaCe instruments

Detection and genotyping of hepatitis D virus from HBsAg positive patients in Iran using RT-PCR

Hepatitis Delta virus [HDV] is a degenerate RNA virus or virusoid and a satellite of Hepatitis B virus [HBV]. Three distinct genotypes are described for HDV; genotype I is distributed worldwide but other genotypes appear to be more restricted geographically. In the present study, an RT-nested PCR method was set up to detect delta infection from serum samples. Moreover, the target amplified sequences corresponding to the Hepatitis delta antigen [HDAg] C-termini were used for genotyping. The results showed that 63.6% [23 of 36] of [HDAb] positive serum samples [as determined by ELISA] were also positive for HDV-RNA. Sequencing and phylogenic analysis of three Iranian HDV isolates revealed the most homology [93%] with an Italian isolate indicating a close relationship and probably a common origin for these isolates