Emre Bodrumlu

Biocompatibility of retrograde root filling materials: A review

The aim of a retrograde filling material is to fill the apical canal space and to obtain a hermetic seal between the periodontium and the root canal system. Several materials have been suggested for root-end filling including: amalgam, gutta-percha, zinc oxide-eugenol cements, glass ionomer cement, gold foil pellets, Cavit, composite resin and mineral trioxide aggregate (MTA). Super-ethoxy benzoic acid and MTA are the most suitable materials and provide better results in apicoectomy procedures than other filling materials. Unfortunately, the ideal material for this purpose has yet to be found. This article is a review of the biocompatibility of retrograde filling materials.

The Resistance of Collagen-associated, Planktonic Cells of Enterococcus faecalis to Calcium Hydroxide

This study examined whether collagen association by an endodontic isolate of Enterococcus faecalis conferred resistance to the bacterium against calcium hydroxide. E. faecalis A197A was grown at 46 degrees C until early stationary phase. Standardized bacterial suspensions were pretreated for 1 hour either with acid-soluble collagen or acidified phosphate-buffered saline (ac-PBS) and cultured to determine the baseline viable bacterial numbers. The bacterial suspensions were challenged with calcium hydroxide solution. Samples were removed at 6, 12, and 24 hours and cultured on tryptone soy agar plates. An adherence assay was performed to confirm that the collagen in the pretreatment medium was bound by the bacteria. Significantly more bacteria were cultivated at 12 hours in the collagen-pretreated group than the ac-PBS-pretreated group (p < 0.01). No bacteria could be cultivated at 24 hours in either group. Collagen association by E. faecalis A197A was found to increase the tolerance of the bacterium to calcium hydroxide.

Solubility of root canal sealers with different organic solvents

OBJECTIVE The aim of this study was to assess the solubility of the new root canal sealer Epiphany and to compare it with 2 conventional sealers against 2 organic solvents commonly used in retreatment. STUDY DESIGN Standardized cylindric glass molds 5 mm wide and 2 mm high were filled with freshly mixed root canal sealers AH Plus, Ketac-Endo, and Epiphany. Samples were stored at 37 degrees C for 2 weeks. Each sample was immersed in chloroform or eucalyptus oil for 2 min, 5 min, and 10 min. The mean percentage loss of weight was determined for each material in each solvent and for each immersion period. RESULTS There were no significant differences at 2 and 5 min (P > .05) for all tested sealers in all immersed solvents. AH Plus and Epiphany sealers showed significantly higher solubilities (P < .05) in chloroform than in eucalyptus oil. Epiphany was the most soluble root canal sealer in both the solvents. Ketac-Endo was the least soluble sealer in both chloroform and eucalyptus oil at all exposure times (P < .05). CONCLUSION The root canal sealers Epiphany and AH Plus dissolved to some extent and more than Ketac-Endo, using either eucalyptus oil or chloroform as the solvent.

The effect of irrigation solutions on the apical sealing ability in different root canal sealers

The aim of this study was to assess the effect of three root canal irrigation solutions on the apical sealing ability of three root canal obturation materials: gutta-percha/AH plus or MM-seal and Resilon/Epiphany SE. A total of 100 teeth with single straight root canals were randomly divided into three equal groups of 30 samples each, with the other 10 teeth (5 positive and 5 negative) used as controls. Each irrigation group was divided into three groups according to the use of three different root canal obturation materials (n = 10): Gutta-percha with AH plus or MM-seal, Resilon with Epiphany SE. The crowns were removed at the cementoenamel junction with a diamond disc under water coolant. The root canals were prepared using step-back technique and irrigation with either sodium hypochlorite (2.5%), chlorhexidine (2%), or MTAD solutions. The roots were obturated with lateral condensation technique using one of the obturation materials. The root surfaces was coated with two layer nail varnish (except apex), placed in 2% methylene blue dye solution, and centrifuged at 3,000 rpm for 5 minutes. Irrigation solutions affected the apical sealing ability of all the sealers. The chlorhexidine irrigation solution exhibited higher apical leakage values than did MTAD and NaOCl in all canal sealers, although the MTAD irrigation solution groups showed the least leakage values. The apical sealing ability of AH plus, Epiphany SE and MM-seal root canal sealers decreased when the chlorhexidine was used as an irrigation solution.

Accuracy of two apex-locating handpieces in detecting simulated vertical and horizontal root fractures.

The aim of this study was to evaluate in vitro the effectiveness of TCM Endo V and Tri Auto ZX handpieces in detecting simulated horizontal and vertical root fractures. Forty extracted maxillary incisor teeth were randomly divided into 2 groups as simulated incomplete horizontal and vertical root fractures. Auto reverse and electronic apex locator functions of the 2 handpieces were used in both groups. Repeated measures of analysis test and pairwise comparisons were used for statistical analyses. Both handpieces detected the root fractures in an acceptable range. Furthermore, electronic apex locator function of both devices was more efficient in the process than auto reverse function.

Effect of F-File on removal of the smear layer: a scanning electron microscope study.

The aim of this study was to evaluate the effectiveness of F-File with NaOCl on removal of the smear layer. A total of 48 single-rooted teeth were instrumented using crown-down technique with one of the irrigation agents: distilled water, 5.25% NaOCl, RC-Prep, Glyde, MTAD or F-File with NaOCl. The remaining smear layer was scored at cervical, middle and apical thirds of the roots with SEM. In all the canals of experimental groups the coronal sections were cleaner than the middle and apical sections except with distilled water (P<0.001). In the coronal third, intensive smear layer was observed in distilled water, NaOCl and F-File groups and less smear layer in MTAD (P<0.05) and least in RC-Prep and Glyde groups. In the middle third, RC-Prep and Glyde groups had less smear layer than the other groups (P<0.001). In the apical third, there was intensive smear layer in all specimens and statistical analyses showed no significant difference among the groups (P>0.05). The F-file failed to improve the effect of NaOCl in removing smear layer.

The antimicrobial and antifungal efficacy of tetracycline-integrated gutta-percha.

The purpose of this study was in vitro evaluation of the antimicrobial and antifungal efficacy of commercially available gutta-percha containing tetracycline on some potential endodontic pathogens. The test microorganisms were Enterococcus faecalis, Pseudomonas aeruginosa, Staphylococcus aureus, Porphyromonas endodontalis, and Candida albicans . Tetracycline-integrated gutta-percha (TGP) cones, tetracycline disc, and conventional gutta-percha cones of the same size were placed on the inoculated plates. The plates were incubated at 37 degrees C aerobically or anaerobically. Growth inhibition zones on each plate were inspected at 24, 48, and 72 h. Tetracycline disc and TGP cones inhibited all the tested bacterial strains, however the greatest antimicrobial effect was seen on S. aureus. Tetracycline disc and TGP seemed less effective on E. faecalis and P. aeruginosa. However, all tested treatments were unable to affect C. albicans . Based on the results of this study, it seems that TGP offers an antimicrobial advantage over conventional gutta-percha.

Temperature Variation During Apicectomy with Er:YAG Laser

OBJECTIVE The purpose of this in vitro study was to evaluate the generated temperature of the Er:YAG laser, with three different pulse durations for apicectomy, compared with tungsten bur and surgical saw. BACKGROUND DATA Apicectomy is an endodontic surgery performed to remove the root apex and curette adjacent periapical tissue because of lesions of the apical area that are not healing properly. METHODS Sixty single-rooted extracted human teeth were resected by three cutting methods: tungsten bur, surgical saw, and Er:YAG laser irradiation with three different pulse durations; pulse duration 50 μs, pulse duration 100 μs, and pulse duration 300 μs. Teflon-insulated, type K thermocouples were used to measure temperature changes during the apicectomy process. Data were analyzed using the general linear models procedure of the SPSS statistical software program. RESULTS Although there was no statistically significant difference for the mean values of temperature changes at 1 mm away to the cutting site of teeth, there was statistically significant difference among groups for the mean values of temperature changes at 3 mm away to the cutting site of teeth. Additionally, there was statistically significant difference among groups for the total time required for apicectomy. CONCLUSIONS The laser irradiation with pulse duration 50 μs appears to have the lowest temperature rise and the shortest time required for apicectomy of the three pulse durations. However, Er:YAG laser for apicectomy in all pulse durations could be used safely for resection in endodontics in the presence of sufficient water.

Temperature variation on root surface with three root-end cavity preparation techniques

INTRODUCTION Thermal changes can occur on the external root surface when root-end cavity preparation is performed, which may damage periodontal ligament cells and alveolar bone. OBJECTIVE The purpose of this study was to evaluate the temperature changes during preparation of the root-end cavities at 1 and 3 mm to the sectioned apical root surfaces when either tungsten carbide round bur, diamond round bur or ultrasonic diamond tip was used. METHODS Root-end resection was performed at 90 degrees to the long axis of the root, 3 mm from the apex. Specimens were randomly divided into three groups of 12 teeth each for three different root-end cavity preparation techniques to be used, i.e. tungsten carbide bur, diamond bur and ultrasonic diamond retro tip.Thermocouples were used to measure temperature changes at 1 mm (T1) and 3 mm (T2) to the cutting plane during the preparations. RESULTS For T1, the lowest and the highest mean temperature increases of 3.53 degrees C and 4.34 degrees C were recorded for the carbide and diamond burs, respectively. For T2, the lowest and the highest mean temperature increases of 2.62 degrees C and 4.39 degrees C where recorded for the carbide and diamond burs, respectively. The mean temperatures with the ultrasonic tip were 3.68 and 3.04 degrees C at T1 and T2 region, respectively. For root-end preparation, the ultrasonic preparation technique took the shortest preparation time (10.25 sec) and the diamond bur took the longest time (28.17 sec). CONCLUSION Ultrasonic retro tips and burs caused temperature to rise from 2.62 degrees to 4.39 degrees C, and these rises were within safety levels.