Super EBA Research Articles

Effect of various zinc oxide materials as root‐end fillings on healing after replantation

This study examined the effect of various zinc oxide materials as root-end fillings of teeth in a replantation model. A total of 35 molar teeth were used from 19 monkeys. After extraction, root ends were resected, the canals contaminated with oral bacteria, root-end cavities prepared and fillings placed prior to replantation. After 8 weeks the teeth and surrounding jaw were removed and prepared for histological examination. Twelve roots were filled with IRM plus dentine chips, and six with Cavit; the tissue response around root ends filled with these materials as assessed by inflammation was similar to that previous reported to IRM and Super EBA cement and was characterized by little or no inflammation of limited extent. In contrast, more severe inflammation was observed around root ends filled with plain zinc oxide-eugenol or Kalzinol; however, the reaction was neither as severe nor as extensive as that to amalgam root-end fillings. Giant cells were observed most often on the surface of fillings with Cavit and zinc oxide-eugenol. It is concluded that the tissue response to IRM with or without added dentine, Super EBA and Cavit was similar and mild; it was less severe than that to zinc oxide-eugenol and Kalzinol. All these materials had a much more favourable response than amalgam

Cytotoxicity of four root end filling materials

Leakage and scanning electron microscopic studies have shown that a mineral trioxide aggregate (MTA) used as root end filling material permits significantly less leakage and has better adaptation than other commonly used root end filling materials. Because these materials are in contact with the periradicular tissues, their cytotoxicity should be evaluated before in vivo tests. Using the agar overlay and radiochromium methods, the cytotoxicity of amalgam, Super EBA, IRM, and the MTA was evaluated. Statistical analysis of the data from the agar overlay technique shows that freshly mixed and set amalgam were significantly less toxic than the rest of tested materials (p< 0.00005). Fresh and set MTA ranked second when tested for cytotoxicity with this technique. Similar statistical tests revealed a significant statistical difference between the toxicity of freshly mixed and set materials after 24 h of incubation with radiochromium-labeled mouse L929 cells. The degree of cytotoxicity of fresh and set materials was MTA least toxic followed by amalgam, Super EBA, and IRM. Based on the results of the cell culture methods used in this study it appears that MTA is a potential root end filling material and warrants further in vivo evaluations.

Antibacterial effects of some root end filling materials

In addition to having good sealing ability, root end filling materials should "ideally" have some antibacterial activity to prevent bacterial growth. This investigation compared the antibacterial effects of amalgam, zinc oxide-eugenol, Super EBA and a mineral trioxide aggregate on nine facultative bacteria Streptococcus fecalis, Streptococcus mitis, Streptococcus mutans, Streptococcus salivarius, Lactobacillus species, Staphylococcus aureus, Staphylococcus epidermidis, Bacillus subtilis, and Escherichia coli B and seven strict anaerobic bacteria, Prevotella (Bacteroides) buccae, Bacteroides fragilis, Prevotella (Bacteroides) intermedia, Prevotella (Bacteroides) melaninogenica, Fusobacterium necrophorum, Fusobacterium nucleatum, and Peptostreptococcus anaerobius. After growing these bacteria on solid media, freshly mixed and 24-h set test materials were placed on the surface of these inoculated media and incubated in the appropriate atmosphere for 24 to 48 h at 37 degrees C. Impregnated discs with the Super EBA liquid were used as positive controls. The antibacterial effects of each material were measured in millimeters and the data were analyzed using one-way and two-way analysis of variance and Scheffé tests to determine the statistical differences between the antibacterial effects of the test materials. Impregnated discs with Super EBA liquid caused varying degrees of growth inhibition for both facultative and strict anaerobic bacteria. Both types of amalgam had no antibacterial effect against any of the bacteria tested in this study. Mineral trioxide aggregate had an antibacterial effect on some of the facultative bacteria and no effect on any of the strict anaerobic bacteria. Zinc oxide-eugenol and Super EBA pastes had some antibacterial effects on both types of bacteria tested.(ABSTRACT TRUNCATED AT 250 WORDS)

PC 21 Correlation between bacterial and silver nitrate penetration using amalgam, super EBA, and composite as retrofillings

PC 21 Correlation between bacterial and silver nitrate penetration using amalgam, super EBA, and composite as retrofillings

PC 23 Microleakage of super EBA with and without finishing

I Microleakage of Super EBA With and Without Finishing. C-L. Hahn, M. Hauser*, R. N. Dodds, VCU/MCV, Richmond, VA. Super EBA (EBA) has been used as an alternative root-end filling material due to its superior sealability and clinical success. The purpose of this s tudy was to evaluate whether finishing EBA after it had set affected the apical seal. Sixty extracted maxillary anter ior teeth were ins t rumented to W[ with at least #60 MAF. Canals were ob tura ted wit] gutta percha prior to root-end resection. A 3 mm deep root -end prepara t ion was per formed on each tooth with ultrasonic tips. Teeth were then randomly divided into 3 groups of 20. Group I received EBA and finishing t reatment with a highspeed finishing bur. Group II received EBA without finishing treatment. Group HI received TERM root-end filling material as a control. Microleakage (ul /min) was measured under 10 psi with a fluid filtration method at day 1, 7, 30 and 90. Multivariate analysis with repeated measures was used to analyze data. Minimal leakage was observed in group HI. There was a significant increase of leakage with time in both EBA groups (p<O.01). There was no statistically significant difference between group I and II. Suppor ted b y Alexander Fellowship, MCV, School of Dentistry.

PC 25 Super EBA cement: An evaluation of an alternative mixing technique

PC 25 Super EBA cement: An evaluation of an alternative mixing technique

RS 27 In vitro cell adhesion on modified super EBA endodontic cement

RS 27 In vitro cell adhesion on modified super EBA endodontic cement

The guided tissue regeneration principle in endodontic surgery: one‐year postoperative results of large periapical lesions

Twenty patients with large endodontic lesions, which failed to respond to conventional endodontic therapy, were selected for this study. The lesions had a radiographic diameter of at least 10 mm, were removed by periradicular surgery, before retrofilling the apices with either super EBA or dessicated zinc oxide-eugenol. In 10 test sites large e-PTFE membranes (Gortex) were placed to cover the lesions, while at the control sites the lesions were not covered before resuturing. Radio-graphic analysis of the lesions at 3, 6, 9 and 12 months revealed that lesions covered with the membranes healed quicker than the control lesions, and that the quality and quantity of the regenerated bone was superior when membranes were used. Results of the study indicate that guided tissue regeneration (GTR) principles can be effectively applied to the healing of large periapical lesions, especially in through-and-through lesions.

Dye leakage of four root end filling materials: Effects of blood contamination

The purpose of this study was to compare the amount of dye leakage (in the presence versus absence of blood) in root end cavities filled with amalgam, Super EBA, IRM, and a mineral trioxide aggregate. After removing the anatomical crowns of 90 extracted human teeth, their roots were instrumented and obturated. Except for their apical 2 mm, the root surfaces were sealed with nail polish. After removal of the apical 2 to 3 mm of each root, a standardized root end cavity was prepared. Five root ends were filled with gutta-percha and no sealer, and another five root ends were filled with sticky wax. These served as positive and negative controls, respectively. The remaining 80 roots were divided into four equal groups and filled with the test materials. For each material, half of the root end cavities were dried prior to placing the filling material. The remaining half were filled after they were contaminated with blood. All 90 roots were then immediately placed in 1% methylene blue dye for 72 h. Finally, the roots were split and linear dye penetration was measured and statistically analyzed (analysis of variance). Presence or absence of blood had no significant effect on the amount of dye leakage. However, the results showed that there was a significant leakage difference between the root end filling materials (p < 0.0001). Mineral trioxide aggregate leaked significantly less than other materials tested with or without blood contamination of the root end cavities.

Sealing ability of a mineral trioxide aggregate when used as a root end filling material

This in vitro study used rhodamine B fluorescent dye and a confocal microscope to evaluate the sealing ability of amalgam, super EBA, and a mineral trioxide aggregate when used as root end filling materials. Thirty single-canal teeth were cleaned, shaped, and obturated with gutta-percha and root canal sealer. After application of nail polish to the external surface, the apical 3 mm of each root was resected and 3-mm deep root end preparations were made. The roots were randomly divided into three groups and the root end preparations filled with the experimental materials. All roots were then exposed to an aqueous solution of rhodamine B fluorescent dye for 24 h, longitudinally sectioned, and the extent of dye penetration measured using a confocal microscope. Statistical analysis showed that the mineral trioxide aggregate leaked significantly less than amalgam and super EBA.

Cytotoxicity of retrofill materials

Dentin bonding agents reduce microleakage and enhance marginal adaption of composite resin restorations. These characteristics are advantages for their use as an endodontic retrofilling material. Because these materials will be in direct contact with vital tissues, their cytotoxic potential must be evaluated before clinical use. It was the purpose of this study to evaluate the cell cytotoxicity of amalgam, Caulk Universal Bond, Gluma, 35% HEMA, Morita Clearfil, Scotchbond 2, Super EBA, Tenure, and Tenure 5-4. VERO cells were grown in RPMI-1640 medium and cell monolayers were prepared by incubating 15 ml of the cell suspension in 60-mm culture dishes at 37 degrees C in 5% CO2. Twelve milliliters of a medium-agarose mixture containing 1% neutral red vital stain were overlayed onto the cell layer and allowed to solidify. The materials were directly exposed to the agarose overlays by inverting 6.0-mm diameter polypropylene capsules containing the cured and liquid sample materials either immediately (0 time) or after placement in phosphate-buffered saline with 1% gentamicin for 7, 15, or 30 days. Cytotoxicity was determined by measuring the zone of killed cells around the sample 24 h after placement on the agarose. Cytotoxicity was determined by measuring the zones of cell inhibition at 24 h and at 7, 15, and 30 days. Initially, all of the materials were found to be cytotoxic, except amalgam and the Tenure components. The dentin bonding primers showed a mean zone of inhibition of 13.2 mm and the cleansers a 40.0-mm zone. Amalgam demonstrated increasing cytotoxicity: 0.0 mm at 24 h to 12.0 mm at 30 days.(ABSTRACT TRUNCATED AT 250 WORDS)

A comparison of the sealing properties of different retrograde techniques: An autoradiographic study

Single-rooted teeth were instrumented and filled in vitro with a lateral condensation of gutta-percha with sealer. Following obturation, the tooth apices were treated by various retrograde procedures. The teeth were then coated with ethyl acetate, immersed in 45Ca solution, washed, and sectioned, and autoradiographs were used to compare the leakage of the various techniques. Statistical analysis indicated that lateral condensation produced a significantly better seal than any retrograde technique tested except retrofilling with Super EBA cement and that a significantly worse seal was obtained with amalgam retrofill when compared to all retrograde techniques except cold-burnished gutta-percha following apicoectomy. No significant difference existed between other group combinations.