Root Canal Filling Materials

Aim  To evaluate marginal seal, water sorption, solubility and loss of mass after brushing of several temporary filling materials.Methodology  For marginal seal, Class I cavities, including endodontic access preparations, were made in human molar teeth and restored using one or other of several temporary filling materials (n = 10): zinc oxide/calcium sulphate-based cement (Cavit, 3M,ESPE, St. Paul, MN, USA), zinc oxide/eugenol cement (IRM, Dentsply Caulk, Milford, DE, USA), glass ionomer cement (Vidrion R, SSWhite, Rio de Janeiro, RJ, Brazil) or a dimethacrylate-based filling (Bioplic, Biodinâmica, Londrina, PR, Brazil). Dye penetration was assessed after thermocycling and immersion in 0.5% basic fuchsine solution. For water sorption, solubility and loss of mass analyses, disc-shaped specimens were made. Water sorption and solubility were evaluated by mass alteration after storage in distilled water for 7 days (n = 7). Loss of mass was calculated based on the difference of mass after abrasion with a toothbrush (n = 5), and surfaces were analysed by SEM. Data of water sorption, solubility and loss of mass were submitted to anova and Tukey’s test, and marginal sealing data to Kruskal–Wallis test (P < 0.05).Results  Statistically significant differences were observed for marginal sealing (P < 0.0001), water sorption (P < 0.01), solubility (P < 0.01) and loss of mass (P < 0.05). Bioplic had the best marginal seal. Cavit had the greatest water sorption and solubility. Vidrion R and Bioplic had the lowest solubility. Loss of mass after brushing was higher for Cavit, followed by Bioplic, IRM and Vidrion R. Cavit and Vidrion R were worn aggressively by brushing.Conclusions  The resin-based temporary filling Bioplic produced the best marginal seal, and was associated with the lowest water sorption, solubility and loss of mass.

This study was conducted to observe the rat subcutaneous connective tissue reaction to implanted dentin tubes that were filled with mineral trioxide aggregate, Sealapex, Calciobiotic Root Canal Sealer (CRCS), Sealer 26, and the experimental material, Sealer Plus. The animals were sacrificed after 7 and 30 days, and the specimens were prepared for histological analysis after serial sections with a hard-tissue microtome. The undecalcified sections were examined with polarized light after staining according to the Von Kossa technique for calcium. At the tube openings, there were Von Kossa-positive granules that were birefringent to polarized light. Next to these granulations, there was irregular tissue, like a bridge, that was Von Kossa-positive. The dentin walls of the tubes exhibited a structure highly birefringent to polarized light, usually like a layer, in the tubules. These results were observed with all the studied materials, except the CRCS, which didn&#39;t exhibit any kind of...

Eighty freshly extracted teeth were endodontically prepared and filled with gutta-percha and either a zinc oxide-eugenol-based sealer or AH26 to determine what effect these sealers, with widely differing properties, would have on apical microleakage after either immediate or delayed dowel space preparation. The teeth were randomly assigned to 1 of 4 groups, and the post space was made either immediately after filling or after being stored in 100% humidity for 1 wk. They were then immersed in a 2% methylene blue solution under vacuum, washed, and split longitudinally. The extent of dye penetration was read by five independent observers and the results analyzed. The only significant difference was in the delayed preparation group with zinc oxide-eugenol sealer, which showed greater leakage than the other groups.

The aim of this study was to compare the resistance of endodontically treated teeth with intraradicular retainer different amounts of remaining coronal structure. Fifty freshly extracted maxillary canines were endodontically treated and randomly assigned to five groups (n=10), as follows: group 1 (control) = teeth with custom cast post and core; group 2 = teeth without remaining coronal structure; group 3, 4 and 5 = teeth with 1 mm, 2 mm and 3 mm of remaining coronal structure, respectively. All specimens in groups 2 to 5 were restored with prefabricated post and resin core. The teeth were embedded in acrylic resin and the fracture strength was measured on a universal testing machine at 45 degrees to the long axis of the tooth until failure. Data were analyzed statistically by one-way analysis of variance and Tukey's test. There was no significant differences (p>0.05) between the control group and group 2, and between groups 3, 4 and 5 (p>0.05). Control group and group 2 had significantly higher resistance strength than groups 3, 4 and 5 (p<0.00001). The findings of this study showed that teeth without remaining coronal structure had significantly higher fracture strength than those with remaining coronal structure (1 mm, 2 mm and 3 mm). When the dental crown was not completely removed, the amount of remaining coronal dentin did not significantly affect the fracture strength of endodontically treated teeth with intraradicular retainer.

The purpose of this study was to compare the sealing ability of the temporary restorative materials Cavit-G, Ketac Molar Easymix, and IRM with a new light-curing temporary material, Clip, using a methylene blue dye penetration test. Endodontic access preparations were prepared in 48 intact extracted human premolars. The teeth were divided into 6 groups, including positive and negative control groups. After access preparation, cotton pellets were placed in the pulp chamber so that the space remaining for the restoration was 4 mm. After thermal cycling for 500 cycles (5 degrees C-55 degrees C), the teeth were immersed in 2% methylene blue solution at neutral (pH = 7.0) in an incubator for leakage assessment. The teeth were sectioned, and the greatest depth of dye penetration was recorded. Marginal leakage was evaluated with a stereomicroscope. Positive control sections exhibited complete dye penetration, and negative controls had none. In the experimental groups, the differences in th...

Root canal sealers used in odontological applications are capable of providing an apical seal, thus inhibiting potential bacterial penetration into the periradicular tissues. Since insolubility is the ideal characteristic for a root canal sealer material, in dentistry the sealability of the material depends on its solubility. This study tested the solubility of six different root canal sealers: two ZnOE-based sealers (Endomethasone C and Argoseal), two calcium hydroxide-containing sealers (Bioseal Normal and Acroseal), and two resin-based sealers (AH Plus and MM Seal). Ten specimens of each material were prepared using stainless steel ring molds with the same internal diameter and the same height in order to obtain similar samples, and immersed in water. Solubility was determined by using sample weight loss (%) after 24 hours and after 2 months. The test was performed according to the International Standards Organization 6876 standard and the American Dental Association specificatio...

Four materials viz. zinc oxide-eugenol, iodoform paste, Kri paste, Maisto&#39;s paste and Vitapex (Calcium hydroxide + iodoform) were tested for their antibacterial effect against the aerobic and anerobic bacteria, viz. Staphylococcus aureus, Streptococcus viridans, Streptococcus faecalis, Bacteroides melaninogenicus and mixed bacterial culture; obtained from infected non-vital deciduous anterior teeth. The antimicrobial sensitivity was checked on BHI-agar plates using well method. The results showed that all the 4 materials were distinctly different from each other in their antimicrobial activity. Maisto&#39;s paste was invariably the superior most in its antibacterial efficacy (in comparison to all the 5 micro-organism strains). Iodoformized zincoxide eugenol appeared to be the second best followed by Kri paste. Vitapex showed the least antibacterial activity.

The cytotoxic effects of a new epoxy resin-based root canal sealer (AH-plus), together with those of two other commonly used endodontic sealers (AH26 and zinc oxide-eugenol), have been studied in vitro on a culture of human gingival fibroblasts. Cytotoxicity was assessed by direct incubation of sealers&#39; extracts with the cultured fibroblasts at different time intervals. Morphological and cytotoxic effects of the sealers were evaluated microscopically and spectrophotometrically using the neutral red cytotoxicity assay. Our results demonstrated that the cytotoxic effects induced by zinc oxide-eugenol were detectable as early as 1 hr after mixing and remained at a high level until completion of the experiment (5 wk). AH26, however, induced early cytotoxic effects that lasted for 1 wk, followed by a substantial reduction in cytotoxicity. Cytotoxicity of the AH-plus was confined to the early period of experiment and was no longer detectable after 4 hr of mixing. Comparison between th...

The microleakage of four retrograde filling materials was compared in vitro. Fifty-three single rooted teeth were instrumentated and root filled with resin chloroform and gutta-percha. The gutta-percha cones were left extruding from the access opening. All teeth were apicected and retrograde fillings placed. The materials used were a non γ2 amalgam (Amalcap), a glass ionomer cement (ChemFil II), threaded titanium pins cemented with a glass ionomer cement (ChemFil II) and identical titanium pins cemented with a silicone material (Adheseal). After removal of the gutta-percha with tweezers, a radioactive isotope solution was placed in the teeth. Extraradicular samples were taken at 3, 7, 28, 77 and 104 days. All retrograde fillings showed some microleakage. The group with titanium pins cemented with silicone showed the least leakage: significantly less than the teeth with glass ionomer cement (P < 0.01) and with amalgam (P < 0.01). No significant differences were found between other groups.

Aim  To compare the major constituents present in ProRoot mineral trioxide aggregate (MTA), ProRoot MTA (tooth coloured formula), ordinary Portland cement and white Portland cement using powder X-ray diffractometery.Methodology  X-ray diffractometery of the four materials was carried out with the divergence and scatter slits set at 1° and the receiving slit at 0.10 mm. The scan range was set at 5–70° and continuous scans for the θ–2θ range were run with a scan speed of 2° min−1. The patterns obtained were then compared with the Powder Diffraction Files (PDF) found in the International Centre for Diffraction Data database. The three strongest peaks were used for the identification of the constituents. The relative intensities were plotted against the angle 2θ and compared with the plots in the PDF.Results  The main constituents were found to be tricalcium silicate, tricalcium aluminate, calcium silicate, and tetracalcium aluminoferrite in all the four cements with the additional presence of Bi2O3 in ProRoot MTA and ProRoot MTA (tooth coloured formula).Conclusions  The four cements had similar major constituents. Data on Portland cement may be used for the further development or modification of ProRoot MTA in order to improve its physical characteristics and expand its scope of clinical applications.

PURPOSE This study evaluated in vivo 2 different obturation techniques (lentulo spiral mounted in a slow-speed handpiece and hand-held) in primary teeth. METHODS The study was carried out on 24 children (mean age = 6.71 years) who had received 50 single-visit zinc oxide and eugenol (ZOE) pulpectomies in primary molars. The root canal filling materials were deposited into the canals either by a lentulo spiral mounted in a slow-speed handpiece or by a hand-held lentulo spiral. Evaluation of pulpectomized molars was performed by both authors immediately and 6 months following treatment using specific clinical and radiographic criteria. In cases of disagreement, the lower rank was selected. RESULTS The study found 64% (16/25) optimal filling (if 1 or more of the canals having ZOE ended at the radiographic apex or up to 2 mm short of the apex) when the lentulo spiral mounted in the slow-speed handpiece was used. It also found a 96% (21/22) clinical success rate in the group obturated by ...

ABSTRACT: Success or failure of endodontic treatment depends, among other parameters, on an accurate determination of the working length. Electronic apex locators (EALs) are a routinely used procedure in endodontic practice; yet their accuracy has been reported to vary from 35%  to 100%. The operating systems of the EALs (frequency or impedance quotient) and different investigative methodologies explain the higher accuracy obtained with the current generation of devices. It is difficult to draw conclusions on the basis of the results obtained with the new generation EALs because of research variables that can influence the results. KEYWORDS: Apex locators, Endodontics, Root apex, Working length
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