in vitro comparative study of apical microleakage of biocalex and white MTA as root-end filling materials

For sealing a cavity prepared in endodontic surgery, there is a need for a material to obtain an apical seal and prevent bacterial and tissue exudates. The purpose of this study was to compare the sealing ability of Biocalex and white MTA as root-end fillings. In this in vitro experimental study, 36 single-rooted extracted human adult teeth with minimum root curvature were cleaned, shaped and obturated with lateral condensation technique, 3 mm of the root apices were resected and a 3 mm deep retrograde cavity was prepared. Teeth were assigned randomly into two groups of 15 teeth each and retrofilled with Biocalex and White MTA. Three teeth served as positive and three teeth served as negative controls. All root surfaces, except the ending part, were covered with two layers of nail polish. Then the roots were stored in 2% methylene blue for 72 hours and then embedded in polyester resin. Next, they were sectioned buccolingually by diamond bur and maximum extent of dye penetration was evaluated through stereomicroscope. Statistical analysis was carried out by student t-test. The level of significance was set at 95%. It was shown that retrofills with Biocalex had significantly less microleakage compared with white MTA. The findings of this study showed that retrograde filling with Biocafex can achieve proper sealing ability and can be used as an alternative for MTA [P<0.001]

Clinical evaluation of various medication methods on the incidence of post-treatment endodontic pain in necrotic teeth

The pain after root canal treatment is one of the main problems for patient and dentist. Various drugs were studied for alleviating the pain after treatment. The purpose of this study was evaluation of various medication methods on the incidence of posttreatment endodontic pain in necrotic teeth. In this controlled double blind clinical trial, 120 patients with single canal teeth and necrotic pulps were selected. The patients were divided into six groups and randomly received drugs in one of the following ways: Group A, 2gr Amoxicillin one hour before treatment. Group B, 2gr Amoxicillin plus 4mg Betamethasone one hour before treatment. In group C, 2gr placebo [control group] one hour before treatment. Group D, 500 mg Amoxicillin immediately after treatment and continued every 8 hours for 4 days. Group E, the same treatment as group D was performed expect that, 4mg Betamethasone was added to Amoxicillin. Group F, the same treatment as group D was performed, but placebo were used instead of Amoxicillin. Root canal therapy was accomplished with step back technique and lateral condensation method. Evaluation of incidence of pain was recorded 6, 12, 24, 48 and 72 hours after treatment. Data were analyzed by Kruskall-wallis and Mann-whitney tests. The results of this study in various intervals showed that there was no significant difference in the incidence of posttreatment endodontic pain between those patients who received Amoxicillin or Betamethasone [A, B, D, E, F] and those who used placebo [control group C, F]. Most of patients that had severe pain received placebo [C and F groups]. Oral administration of corticosteroids plus antibiotic in cases with necrotic pulp did not significantly reduce posttreatment endodontic pain

[Comparison of remaining obturating material on canal walls using rotary and hand instrumentation techniques for endodontic re-treatment]

Inadequate removal of the original obturating material during non-surgical endodontic retreatment may lead to failure of root-canal therapy. The purpose of this in vitro study was to quantify and compare the percentage of root canal area occupied by remaining gutta-percha, employing rotary and hand instrumentation techniques with and without use of chloroform. Ninety extracted single-rooted human teeth were prepared by a passive step-back technique in three different working lengths: optimum increased [over-instrumented] and reduced [under-instrumented]. Obturation was performed by a combination of cold lateral and warm vertical compaction methods. The teeth were divided into 3 groups according to the methods used for gutta-percha removal: Group A, stainless steel K-type hand files plus chloroform; Group B, rotary Ni-Ti files plus chloroform; and Group C, rotary Ni-Ti files without chloroform. The roots were sectioned longitudinally and the percentage of root canal area occupied by root-filling material was calculated by a digital stereomicroscope in three levels: coronal, middle and apical. Data were analyzed by ANOVA. The coronal two-thirds contained larger amounts of filling material in all 3 groups, but the difference was not significant. A significantly smaller amount of gutta-percha/sealer was found in the middle and apical thirds in group C [P<0.05]. The relative percentage of canal area occupied by obturating material was not significantly different among the 3 working-lengths. The use of rotary files without solvent resulted in cleaner canals. However, completely clean root canal walls were not achieved with any of the studied instruments

Comparison of the extruded apical debris rate following rotary and hand instrumentation techniques during endodontic retreatment

Non-surgical retreatment is a way to correct the factors responsible for the failure of previous endodontic treatment. In recent years, rotary instrumentation systems have created a new option for both clinicians and patients. The aim of the present study was to quantify and compare the amount of debris extruded from apical foramen during endodontic retreatment using rotary and hand instrumentation techniques with and without use of chloroform. In this invitro experimental study, root canals of 96 extracted single-root human teeth were instrumented by passive step back technique in three different working lengths: optimum, over and under [three subgroups: a, b, c]. they were then obturated by a combination of cold lateral and warm vertical compaction methods. After removal of gutta-percha, re-instrumentation was performed in three groups as follows: group A; stainless sled K-type hand files plus chloroform, group B; rotary Ni-Ti files plus chloroform and group C; rotary Ni-Ti files without chloroform. Finally, the weight of extruded debris was blindly determined. The results were analyzed by Univariate ANOVA. In all groups, the mean weight for extruded debris was not more than 0.37 gr. The weight of extruded debris was ranked as: Group B>Group C>Group A. The differences between three groups and subgroups were statistically significant [P<0.001]. The results of this study showed that the largest amount of extruded debris during retreatment was found after using rotary files with solvent and in canals with overfilled obturation

[ comparative study of sealing ability of Roth Sealer with ZOE, Tubli-Seal and AH26]

Introduction: apical seal is an important factor in successful root canal therapy. Still there are controversies about sealing ability of various sealers materials. Recently Roth-Sealer which is very popular in Europe and U.S.A has been produced by an Iranian company. The purpose of this study was to compare sealing ability of Iranian Roth Sealer with ZOE, Tubli-Seal and AH26

Materials and Methods: in this study, we used 100 fresh extracted single root teeth of human. After cutting the crown from CEJ and determination of working length, canal preparation was done with passive step back technique using patency file. The teeth randomly were divided into 6 groups. Four groups with 20 teeth for experimental groups and two groups with 10 teeth as positive and negative control groups. Obturation was done with lateral condensation in four groups with Roth Sealer, ZOE, tubli-Seal and AH26. The coronal seal was achieved with amalgam. In positive control group, we did not use sealer after preparation all teeth were incubated at 37 OC temperature and 100% humidity for 72 hours. All teeth were covered with two coats of nail polish and sticky wax except 2mm of apical part. In the group of negative control, all of the tooth surface were covered. Dye penetration was measured using Indian ink [PH=6.2]. After splitting the teeth longitudinally, dye penetration was measured by stereomicroscope. Data were analyzed with ANOVA and DUNCAN tests

Results: showed that dye penetration in positive control group was complete and significantly more than other groups while in negative control group, no dye penetration was observed and in Roth Sealer group, it was significantly less than other groups[P<0.05]. There was no significant difference between ZOE, Tubli Seal and AH26

Conclusion: Iranian Roth sealer proved to be appropriate for root canal therapy compared to other 3 sealers. So, this can be considered as a substitute for foreign Roth sealer which is very expensive. Performing histologic studies on it for confirmation is recommended