• Restorative Dentistry and Endodontics
• /
• v.37 no.3
• /
• pp.149-154
• /
• 2012

Objectives: To evaluate the accuracy of the Root ZX in teeth with simulated root perforation in the presence of gel or liquid type endodontic irrigants, such as saline, 5.25% sodium hypochlorite (NaOCl), 2% chlorhexidine liquid, 2% chlorhexidine gel, and RC-Prep, and also to determine the electrical conductivities of these endodontic irrigants. Materials and Methods: A root perforation was simulated on twenty freshly extracted teeth by means of a small perforation made on the proximal surface of the root at 4 mm from the anatomic apex. Root ZX was used to locate root perforation and measure the electronic working lengths. The results obtained were compared with the actual working length (AWL) and the actual location of perforations (AP), allowing tolerances of 0.5 or 1.0 mm. Measurements within these limits were considered as acceptable. Chi-square test or the Fisher's exact test was used to evaluate significance. Electrical conductivities of each irrigant were also measured with an electrical conductivity tester. Results: The accuracies of the Root ZX in perforated teeth were significantly different between liquid types (saline, NaOCl) and gel types (chlorhexidine gel, RC-Prep). The accuracies of electronic working lengths in perforated teeth were higher in gel types than in liquid types. The accuracy in locating root perforation was higher in liquid types than gel types. 5.25% NaOCl had the highest electrical conductivity, whereas 2% chlorhexidine gel and RC-Prep gel had the lowest electrical conductivities among the five irrigants. Conclusions: Different canal irrigants with different electrical conductivities may affect the accuracy of the Root ZX in perforated teeth.

• The Journal of the Korean dental association
• /
• v.56 no.10
• /
• pp.556-566
• /
• 2018

Whether you use a hand file or an engine-driven file, you cannot remove bacteria completely from the root canal by mechanical work alone. If the root canal is well cleaned, endodontic irrigants will well penetrate into these areas that will not be mechanically accessible. It will decompose and remove the biofilm and also remove the smear layer to reach the dentinal tubule. Clinicians who are not yet using NaOCl as their primary irrigant, should be aware that there are no other irrigants that offer all the benefits of NaOCl and are inexpensive. Clinicians may be reluctant to use it because of concern about NaOCl accident, but this possibility is extremely low if used with caution.

• Journal of Dental Rehabilitation and Applied Science
• /
• v.33 no.2
• /
• pp.106-113
• /
• 2017

Purpose: The purpose of this study was to evaluate tissue dissolving capacity, antimicrobial effect of Hydroxyethylidene bisphosphonate (HEBP) interacting with sodium hypochlorite (NaOCl), Ethylenediaminetetraacetic acid (EDTA) as conventional endodontic irrigants and to determine tissue dissolving efficacy depended on temperature. Materials and Methods: A total of 80 bovine muscles were randomly distributed into 8 groups (n = 10). After their initial weights determined on a precision scale, the specimens in each group were immersed in the solutions for 5, 10 and 15 min and reweighted at each time period. Agar diffusion test inoculated with Enterococcus faecalis was performed for antimicrobial effect of each endodontic irrigants. Results: The ability to dissolve organic matter was greater in NaOCl group following NaOCl and HEBP mixture. Heated NaOCl ($40^{\circ}C$) and NaOCl/ HEBP mixture was greater tissue dissolving efficacy than room temperature ($25^{\circ}C$). Antimicrobial effect was greater and significant in the following order EDTA > EDTA + 1% NaOCl > $1%\;NaOCl{\geq}1%\;NaOCl$ + HEBP. Conclusion: HEBP as soft chelating agent does not disturb antimicrobial effect and less affected tissue dissolving efficacy as inherent properties of NaOCl. In the heated NaOCl/HEBP mixture analyzed, it dissolved more the organic matter than room temperature.

• Restorative Dentistry and Endodontics
• /
• v.11 no.1
• /
• pp.27-32
• /
• 1985

The purpose of this study was to examine the influence of canal irrigants and smear layer on the property of apical seal. Fourty-five canals from human teeth were randomly selected and divided into 5 groups according to the irrigants used in conjunction with instrumentation. The irrigants were RC-prep in combination with Naocl, Citric acid, Naocl, Naocl in combination with $H_2O_2$, and normal saline solution. After instrumention and dry the canal with paper point, the canals were obturated by lateral condensation of Zinc-oxide eugenol sealer and gutta percha cone. All the specimens were immersed in 2% methylene blue dye solution for 7 days and the depth of dye penetration into the canals was evaluated by macros cope. The following results were obtained. 1. All the canals experimented showed varying degree of dye penetration. 2. There was no significant difference in depth of dye penetration between the groups known to be effective and ineffective in the removal of the smear layer. 3. The canals irrigated with NaOCl alone showed the highest dye penetration and mean leakage was 7.7 mm. 4. In the canals irrigated with RC-prep in combination with Naocl and citric acid, the mean dye penetration was 5.5 mm and 4.8 mm respectively, and the canals irrigated with NaOCl in combination with $H_2O_2$ and normal saline solution revealed mean dye penetration of 3.9 mm.

• Restorative Dentistry and Endodontics
• /
• v.47 no.4
• /
• pp.44.1-44.1
• /
• 2022

• Restorative Dentistry and Endodontics
• /
• v.45 no.4
• /
• pp.45.1-45.8
• /
• 2020

Objective: The aim of this study was to introduce a gelatin/bovine serum albumin (BSA) tissue standard, which provides dissolution properties identical to those of biological tissues. Further, the study evaluated whether the utilization of endodontic activating devices led to enhanced phantom dissolution rates. Materials and Methods: Bovine pulp tissue was obtained to determine a benchmark of tissue dissolution. The surface area and mass of samples were held constant while the ratio of gelatin and BSA were varied, ranging from 7.5% to 10% gelatin and 5% BSA. Each sample was placed in an individual test tube that was filled with an appropriate sodium hypochlorite solution for 1, 3, and 5 minutes, and then removed from the solution, blotted dry, and weighed again. The remaining tissue was calculated as the percent of initial tissue to determine the tissue dissolution rate. A radiopaque agent (sodium diatrizoate) and a fluorescent dye (methylene blue) were added to the phantom to allow easy quantification of phantom dissolution in a canal block model when activated using ultrasonic (EndoUltra) or sonic (EndoActivator) energy. Results: The 9% gelatin + 5% BSA phantom showed statistically equivalent dissolution to bovine pulp tissue at all time intervals. Furthermore, the EndoUltra yielded significantly more phantom dissolution in the canal block than the EndoActivator or syringe irrigation. Conclusions: Our phantom is comparable to biological tissue in terms of tissue dissolution and could be utilized for in vitro tests due to its injectability and detectability.

• Restorative Dentistry and Endodontics
• /
• v.44 no.1
• /
• pp.8.1-8.7
• /
• 2019

Objectives: Irrigants are imperative in endodontic therapy for the elimination of pathogens from the infected root canal. The present study compared the antimicrobial efficacy of octenidine dihydrochloride (OCT) with chlorhexidine (CHX) and sodium hypochlorite (NaOCl) against Staphylococcus epidermidis (S. epidermidis) for root canal disinfection. Materials and Methods: The minimum inhibitory concentration (MIC) was obtained using serial dilution method. The agar diffusion method was then used to determine the zones of inhibition for each irrigant. Lastly, forty 6-mm dentin blocks were prepared from human mandibular premolars and inoculated with S. epidermidis. Samples were randomly divided into 4 groups of 10 blocks and irrigated for 3 minutes with saline (control), 2% CHX, 3% NaOCl, or 0.1% OCT. Dentin samples were then collected immediately for microbial analysis, including an analysis of colony-forming units (CFUs). Results: The MICs of each tested irrigant were 0.05% for CHX, 0.25% for NaOCl, and 0.0125% for OCT. All tested irrigants showed concentration-dependent increase in zones of inhibition, and 3% NaOCl showed the largest zone of inhibition amongst all tested irrigants (p < 0.05). There were no significant differences among the CFU measurements of 2% CHX, 3% NaOCl, and 0.1% OCT showing complete elimination of S. epidermidis in all samples. Conclusions: This study showed that OCT was comparable to or even more effective than CHX and NaOCl, demonstrating antimicrobial activity at low concentrations against S. epidermidis.

• Restorative Dentistry and Endodontics
• /
• v.23 no.1
• /
• pp.379-390
• /
• 1998

In endodontic treatment, calcium hydroxide has been used as intracanal medicament. Although calcium hydroxide should be removed thoroughly before permanent root canal filling, no effective method for its removal has been reported. Because of irregularity of root canal walls, root curvatures and anatomic variations, it is insufficient to remove calcium hydroxide from the canal wall only by mechanical instrumentation Considering the chemical effects of irrigants on calcium hydroxide, $Ca^{++}$ dissolving effect from two calcium hydroxide products is investigated, using dis- tilled water, NaOCl, citric acid and EDTA. Vitapex$^{(R)}$ 0.1g and calcium hydroxide 0.03g were dissolved in distilled water, 5% NaOCl, 50% citric acid and 17% EDTA respectively, at 1, 3, 5, 10min. time interval. The solution was filtered using filter paper(pore size $5{\mu}m$) and $Ca^{++}$ concentration was determined by ion chromatography. The result were as follows : 1. Distilled water, NaOCl, citric acid and EDTA abstracted more $Ca^{++}$ from calcium hydroxide than Vitapex$^{(R)}$ except NaOCl 1, 5, 10 time interval. 2. EDTA and citric acid abstracted more $Ca^{++}$ from Vitapex$^{(R)}$ and calcium hydroxide than distilled water or NaOCl. The overall result support the view that water-based calcium hydroxide product is easily removed than oil-based calcium hydroxide product and EDTA, citric acid are more effective in $Ca^{++}$ elution than NaOCl or distilled water.

• Restorative Dentistry and Endodontics
• /
• v.15 no.1
• /
• pp.175-186
• /
• 1990

The purpose of this study was to determine whether any clinical factors or conditions are associated with an increased incidence or degree of pain occuring during endodontic treatment in patients who begin treatment with no symptoms. The 260 teeth of 256 patients were surveyed and statistical analysis was used to determine whether a significant relationship existed between pain and any recorded clinical factors or conditions. The following conclusions were drawn. 1. No significant relationship between interappointment pain and any of the analyzed clinical factors or conditions except for fistula formation could be determined. 2. The presence of a draining fistula from a periapical lesion significantly decreased the posttreatment pain. 3. The judicious use of canal irrigants and canal medicaments is not associated with an increased incidence or degree of interappointment pain.

• Restorative Dentistry and Endodontics
• /
• v.18 no.1
• /
• pp.95-102
• /
• 1993

Two functions of root canal medicaments and irrigants are to reduce microorganisms and to encourge the repair of apical tissues. The biocompatibility of endodontic materials has been tested using in vitro cell culture techniques. The purpose of this study Was to evaluate and compare the cytotoxic effects of 2 root canal irrigation solutions and 4 antiseptics on HEp-2 and McCoy cells. Two irrigation solutions were sodium hypochlorite. $H_2O_2$ and 4 antiseptics were povidone, ethanol, glutaraldehyde and benzalkonium chloride. Each solutions were serially diluted to 1:1, 1:10, 1:$10^2$, 1:$10^3$, 1:$10^4$, 1:$10^5$, 1:$10^6$. And each diluted solutions were added to the cells and cytotoxic effects were measured with the absorbance of formazan formed cells by ELISA READER. The results were as follows : 1. Benzalkonium chloride was the most cytotoxic on HEp-2 cell. (P<0.05) 2. $H_2O_2$ was the most cytotoxic on McCoy cell. (P<.05) 3. Povidone and ethanol showed mild cytotoxic effect on HEp-2 and McCoy cell. (P<0.05).