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Copyright of Biotechnology in Animal Husbandry is the property of Institute for Animal Husbandry and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Aim To evaluate the in vitro genotoxicity and cytotoxicity of two resin-based root canal sealers and to determine the type of cell death they induce. Methodology The sealers tested were Epiphany and RealSeal. Each component of the material (Epiphany Primer, Epiphany Thinning Resin, Epiphany Sealant, RealSeal Primer, RealSeal Thinning Resin and RealSeal Root Canal Sealant), components in permutual combinations and all components mixed together were tested on human peripheral blood leucocytes using ethidium bromide/acridine orange viability staining and comet assay. Simultaneously, untreated negative control cultures were analysed in the same manner. DNA damage was evaluated following 4 h of treatment and after 24 h in the absence of the components of the materials. Results After 4 h of treatment, except thinning resin, each individual component and the different combinations of components induced a significant increase in DNA migration ability (P < 0.05). After 24 h, combination of primer, thinning resin and sealant of both materials caused cell death inducing intense apoptosis. After 24 h, cells exposed to Epiphany Sealant and RealSeal Root Canal Sealant, both in polymerized and unpolymerized form, exhibited a level of DNA damage that was similar to the control. Conclusions Primer and thinning resin of both resin-based root canal sealers and their combinations were cytotoxic and induced apoptosis. Both sealants had no significant effect on the viability of the human leucocytes. [ABSTRACT FROM AUTHOR]

Aim To study in vitro the cytotoxic and mutagenic effects of AH26 and AH Plus. Methodology Cytotoxic effects on Chinese hamster V79 cells were determined by counting viable cells following incubation with eluations of AH26 and AH Plus. In one set of experiments, the materials were mixed, set for 1 h and then eluted with dimethyl sulphoxide (DMSO) for 1 h,24 h and 7 days. In the other set, AH26 and AH Plus were mixed and set for 1 h, 24 h and 7 days in physiological saline then crushed and eluted in DMSO for 24 h. The cytotoxic effects of these eluates were evaluated. Three concentrations were chosen to examine the mutagenic effects of AH26 and AH Plus:5.57,16.7 and 55.7 &mi'g mL[SUP-1]. The structural chromosomal aberration analysis and micronucleus test were performed on human lymphocytes according to standard procedures. Results Dose-response curves of cell survival were obtained. Both materials were shown to be cytotoxic in doses larger than 55.7 μg mL[SUP-1], except for AH26, after 7 days setting time. AH Plus was also shown to be toxic in concentrations of 16.7 μg mL[SUP-1], except after 7 days setting time. Neither AH26 nor AH Plus induced a significant increase of chromosomal aberrations or micronuclei induction at any setting time or concentration. Conclusion There was no mutagenicity found for AH26 and AH Plus on human lymphocytes in highly controlled conditions in vitro. [ABSTRACT FROM AUTHOR]

Abstract Aim To evaluate the penetration of Candida albicans alone and a combination of bacteria through root canals filled with gutta-percha and one or other root canal sealers, AH26 and AH Plus. Methodology Eighty teeth were randomly divided into two groups of 40 teeth each and obturated with gutta-percha using either AH26 or AH Plus sealer. A further 10 teeth served as negative controls and 10 as positive controls. The external surface of each root, except the apical 2 mm, was covered with two layers of nail varnish. The teeth were inserted into Eppendorf plastic tubes and suspended in glass bottles containing sterile Schaedler broth. Streptococcus mutans , Streptococcus mitis , Prevotella melaninogenica and Lactobacillus acidophilus were placed in the access cavities of 20 teeth filled with AH26 and 20 with AH Plus. Candida albicans was placed in the access cavities of the other teeth. The culture medium with microorganisms was changed every 7 days. Every 72 h bacterial or fungal growth in the broth was tested up to a period of 90 days. Results Leakage in the experimental teeth occurred between 14 and 87 days. Leakage was present in 47% of all samples. From the samples with AH26, 45% leaked bacteria and 60% leaked fungi; whilst from the samples with AH Plus, 50% leaked bacteria and 55% fungi. There was no statistically significant difference in penetration of bacteria and fungi between the sealers. Conclusion In this in vitro study, gutta-percha and the sealers AH26 and AH Plus allowed leakage of bacteria and fungi. [ABSTRACT FROM AUTHOR]

Abstract – The aim of this study was to evaluate the cytotoxic effect of four root canal sealers: AH26, AH Plus, Diaket and Apexit. In the experiment two cell lines, human cervical carcinoma (HeLa) cells and mouse skin fibroblasts (L929), were used. Under aseptic conditions, the sealers were prepared according to the manufacturers' directions, and 0.01 mL of each material was placed in a 24-well plate. The sealers were covered with cell suspension. The cytotoxicity was estimated by determining the number of viable cells by a light microscope, as well as the total number of cells 24 h, 48 h and 120 h after the treatment with mentioned materials. The results obtained in this study showed the high cytotoxcity of the new AH Plus root canal sealer, which was shown to be equally or more toxic to the standard AH26 and Diaket materials. Apexit was the least toxic sealer. [ABSTRACT FROM AUTHOR]

Aim The aim of this study was to examine the apical sealing ability of five root canal sealers using a fluid transport model. Methodology A comparison of root canal sealers AH26, AH Plus, Diaket, Apexit, and Ketac-Endo were tested on 60 single-rooted teeth. The coronal part of each tooth was removed at the amelo-cemento junction, and also 3 mm of the root tip. Root canals were instrumented using the ‘step-back’ technique with Gates Glidden drills and irrigated with 2.5% NaOCl. The specimens were divided into five groups of 10 samples each and filled with test materials and gutta-percha points by the cold lateral condensation technique. Ten teeth were used as a control group, out of which five served as negative and five as positive controls. The leakage was measured by the movement of an air bubble in a capillary glass tube connected to the experimental root section. Results The differences in leakage amongst Ketac-Endo (0.318μL; SD 0.084), AH26 (0.319μL; SD 0.075), AH Plus (0.330L; SD 0.085) Apexit (0.360μL; SD 0.127) and Diaket (0.387μL; SD 0.140) were not statistically significant (P 0.05). Conclusions Under the conditions of this study, all five sealers produced a satisfactory seal. [ABSTRACT FROM AUTHOR]

The calcium hydroxide-based filling material Apexit, which is often used in endodontic practice, was evaluated for its antibacterial and antifungal effects against microorganisms isolated from oral cavity ( Serratia marcescens, Pseudomonas putida, Staphylococcus aureus, Candida albicans). Two different quantitative techniques were employed—the direct-contact test was used to examine the efficacy of freshly mixed material while the broth-survival test was employed to check the antimicrobial properties of 5-d-old material. Apexit inhibited Gram-negative bacteria more effectively than Gram-positive ones but had none or a very weak inhibitory effect on C. albicans. [ABSTRACT FROM AUTHOR]

Abstract Aim To examine the use of an Nd:YAG laser in removing gutta-percha fillings from root canals when used in conjunction with eucalyptol, dimethylformamide (DMF) or no solvent. Methodology Root-canal fillings (sealer and gutta-percha) were removed with laser irradiation of 20 Hz/1.5 W from 30 roots randomly divided in three groups. In group 1, the solvent was eucalyptol; in group 2, the solvent was DMF; and in group 3, no solvent was used. Laser irradiation was performed until the temperature measured on the root surface increased by 4 °C over room temperature. The treatment was deemed complete when the apical foramen was reached with the optical fibre and a reamer. The samples were split longitudinally, and the area of remaining gutta-percha on the root-canal walls was determined with the aid of a computer program. The total number of laser pulses to achieve length and the highest temperature recorded was determined for each tooth. The results were statistically analysed using Student's t -test (P < 0.05) for independent samples. Results The average temperature increase in group 1 was 9.17 ± 0.56 °C; in group 2, 9.56 ± 0.28 °C; and in group 3, 8.29 ± 0.41 °C. The shortest time to achieve length was in group 3 (6.4 ± 0.49 min), then in group 1 (6.7 ± 0.85 min) and group 2 (7.05 ± 0.79 min). The area of remaining gutta-percha was the largest in group 2 (6.13 ± 5.76%), whilst the smallest was for group 3 (4.69 ± 4.03%), but the difference was not statistically significant. The number of pulses was not statistically significant between the groups. Conclusions Use of an Nd:YAG laser alone is capable of softening gutta-percha. The addition of solvents did not improve the retreatment, either in terms of the time required for the procedure or in terms of the area of remaining gutta-percha on root-canal walls. [ABSTRACT FROM AUTHOR]