doxycycline-hyclate and Smear-Layer

The objective of this study was to evaluate and compare in vitro the decalcifying capability on root canal dentin of 4 different irrigating solutions.. Twenty-five freshly extracted maxillary central incisors were selected. The canals were prepared to obtain a total of 4 samples from each root. The samples were randomly divided into 5 equal experimental groups (n = 20) according to the irrigating solutions tested (Tetraclean, Largal Ultra, 17% ethylenediaminetetraacetic acid, Tubuliclean). For each irrigating solution, the specimens were immersed for 5, 10, and 15 minutes. After exposures, the concentration of Ca(2+) extracted was measured by inductively coupled plasma-atomic emission spectrometry. Data were analyzed by means of nonparametric tests, and statistical analysis was performed.. The higher release of Ca(2+) was observed in samples treated with Tetraclean; this citric acid-based agent showed significantly higher decalcifying capability. For all irrigating solutions tested, 10 minutes of application are sufficient to obtain the maximum Ca(2+) release.. The results indicated that Tetraclean could be applied to obtain more efficient removal of the smear layer and to facilitate the biomechanical instrumentation procedures.

Topics: Calcium; Cetrimonium; Cetrimonium Compounds; Citric Acid; Dental Pulp Cavity; Dentin; Doxycycline; Drug Combinations; Edetic Acid; Humans; Materials Testing; Middle Aged; Polymers; Polypropylenes; Propylene Glycols; Root Canal Irrigants; Root Canal Preparation; Smear Layer; Spectrophotometry, Atomic; Time Factors

To evaluate the intratubular antimicrobial activity of several oxidant and chelating agents associated with or without surfactants in experimentally infected root canals, using confocal laser scanning microscopy.. Twenty-four dentine blocks from bovine incisors were contaminated for 5 days with Enterococcus faecalis (ATCC- 29212). Ten contaminated dentine specimens were irrigated for 5 min with 5.25% NaOCl followed by 17% EDTA for 2 min, and the other 10 with Hypoclean for 5 min followed by Tetraclean NA for 2 min. The remaining four specimens were used as positive and negative controls (two samples each). Then, dentine blocks were stained with Live/Dead BacLight for analysis of the remaining live or dead bacteria using confocal laser scanning microscopy. Comparison between and within groups was performed using the Mann-Whitney test for independent samples and the Wilcoxon signed-rank test, respectively.. After exposure to irrigants, the positive control group had a median of 67.41% of viable bacteria (95% CI: 48.15, 78.9), whilst the NaOCl+EDTA group and Hypoclean+Tetraclean NA group had 3.77% (1.28, 15.92) and 0.87% (-0.42, 4.30) of viable bacteria, respectively. These results were significantly different from each other, both overall and distinct by region (cervical and medium third), or depth (superficial and deep layer) (P < 0.01 in all cases).. The use of adjunctive agents reducing the surface tension associated with oxidant and chelating agents improved the antimicrobial activity of irrigating solutions and intratubular decontamination against Enterococcus faecalis, possibly due to better removal of the smear layer and deeper penetration into dentinal tubules.

Topics: Animals; Anti-Infective Agents; Cattle; Cetrimonium Compounds; Chelating Agents; Citric Acid; Dental Pulp Cavity; Dentin; Doxycycline; Drug Combinations; Edetic Acid; Enterococcus faecalis; Incisor; Microbial Viability; Microscopy, Confocal; Oxidants; Polypropylenes; Root Canal Irrigants; Smear Layer; Sodium Hypochlorite; Surface Tension

In this ex vivo study, the surface cleanliness of root canal walls after shaping with Ni-Ti instruments and irrigating with different endodontic solutions was evaluated by SEM.. 50 single-rooted teeth were divided into 5 groups. All root canals were shaped with Revo-S™ (MICRO-MEGA®, Besancon, France) rotary Ni-Ti instruments and irrigated with NaOCl, varying the final rinse: NaOCl, Tetraclean, 17% EDTA, Cloreximid, Tetraclean liquid not mixed with powder. Specimens were fractured longitudinally and prepared for SEM analysis in order to evaluate the presence/absence of smear layer and the presence/absence of open tubules at the coronal, middle, and apical third of each canal, using a 3-step scale for scores. Numeric data were analyzed using Kruskall-Wallis test and Mann-Whitney U test and significance was predetermined at p<0.05.. This study showed significant differences between the various groups. The 5.25% NaOCl + Tetraclean and 5.25% NaOCl + 17% E.D.T.A. groups had significantly lower scores than other groups (p<0.001), with no significant difference between them.. Final rinse with Tetraclean is effective in removing the smear layer, leaving a high number of opened dentin tubules.

Topics: Anti-Infective Agents; Cetrimonium Compounds; Chlorhexidine; Citric Acid; Dental Instruments; Dental Pulp Cavity; Dentin; Doxycycline; Edetic Acid; Equipment Design; Humans; In Vitro Techniques; Microscopy, Electron, Scanning; Nickel; Polypropylenes; Root Canal Irrigants; Root Canal Preparation; Smear Layer; Sodium Hypochlorite; Titanium