Comparative evaluation of effect of sodium hypochlorite and chlorhexidine in dental unit waterline on aerosolized bacteria generated during dental treatment

BACKGROUND

In dentistry, nosocomial infection poses a great challenge to clinicians. The microbial contamination of water in dental unit waterlines (DUWLs) is ubiquitous. Such infected DUWLs can transmit oral microbes in the form of aerosols. Previous studies have suggested treating DUWLs with various disinfectants to reduce cross-contamination. The literature lacks a comparative evaluation of the effect of the use of 0.2% chlorhexidine (CHX) and 0.1% sodium hypochlorite (NaOCl) in DUWLs on aerosolized bacteria generated during dental procedures.

OBJECTIVE

To compare the effect of NaOCl and CHX in DUWLs on aerosolized bacteria generated during restorative and endodontic procedures.

MATERIALS AND METHODS

A total of 132 patients were equally divided into three groups (n = 44 in each group) according to the content of DUWL as follows. Group I-0.1% NaOCl Group II-0.2% CHX Group III-distilled water (Positive control) One-way ANOVA was performed and the Kruskal-Wallis test was used for intergroup comparison.

RESULTS

For the restorative procedure, inter-group comparison of mean colony-forming units (CFU) scores showed a statistically significant difference between the groups (p - .001) with the score of group 3 higher than group 2 followed by group 1. For the endodontics, an inter-group comparison of CFU scores showed a statistically significant difference between the groups (p - .003) with the mean score in group 1 being the lowest and group 3 being the highest.

CONCLUSION

The addition of NaOCl or CHX in DUWLs shows an effective reduction in aerosolized bacteria compared to distilled water.

Comparative Evaluation of Antimicrobial Efficacy of Various Antibiotic Pastes and Calcium Hydroxide Using Chitosan as a Carrier Against Enterococcus faecalis: An In Vitro Study

INTRODUCTION

The use of intracanal medicaments between appointments can serve as an important aid in the sterilization of the root canal system. Calcium hydroxide is commonly used, but it is not completely effective against Enterococcus faecalis. A triple antibiotic paste (TAP) is used but has the problem of tooth discoloration. Double antibiotic paste (DAP) or modified TAP (MTAP) has been suggested to solve this. Chitosan has been used as a vehicle in pharmacology, and it has inherent antibacterial properties too.

OBJECTIVE

This study compares the efficacy of DAP and MTAP using chitosan as a vehicle with calcium hydroxide.

MATERIALS AND METHODS

Sixty single-rooted teeth were taken and decoronated with a length of 13 mm. Biomechanical preparation (BMP) was done with #3 Gates-Glidden (GG) drills, 17% ethylenediaminetetraacetic acid (EDTA), and 5.25% sodium hypochlorite (NaOCl) used for irrigation. These were kept in microcentrifuge tubes with 1 ml brain heart infusion (BHI) broth. Contamination was done with E. faecalis strain for 21 days. DAP and MTAP pastes were prepared and added to the chitosan solution. Groups were divided into 10 each, each medicament with saline or chitosan as the vehicle. The microbial load was measured at the end of two and seven days.

RESULTS

The level of significance was kept at p = 0.05. Statistical analysis was done with the Kruskal-Wallis test and analysis of variance (ANOVA). DAP and MTAP groups with chitosan showed a significant reduction in the microbial load when compared to calcium hydroxide with chitosan.

CONCLUSION

DAP and MTAP with chitosan can be effective intracanal medicaments against E. faecalis in refractory endodontic cases.

Comparative evaluation of four different root canal irrigation techniques for apical extrusion of sodium hypochlorite - An in vitro study

Objective

This study compared the potential for apical extrusion of sodium hypochlorite (NaOCl) when using needle irrigation (NI), passive ultrasonic irrigation (PUI), passive subsonic irrigation (PSI), and negative pressure system (NP).

Materials and Methods

One hundred freshly extracted human permanent anterior teeth with complete root formation were embedded rigidly in agarose gel-containing cresol purple. Teeth were randomly allocated to six groups: G1-NI; G2-PUI; G3-PSI; G4-NP; G5-positive control; and G6-negative control. The chemomechanical preparation was completed and 12 ml of 3% NaOCl was delivered for 180 s in all groups. Dye diffusion was standardized by doing gel photography after the NaOCl final irrigation the Chi-square test and Kruskal-Wallis one-way analysis of variance test were used for the data analysis.

Results

G1 had statistically significant apical extrusion compared to G2 (P = 0.001), G3 (P = 0.001), and G4 (P = 0.001) groups. G4 showed the least amount of apical extrusion.

Conclusions

pH-sensitive gel model is useful in evaluating NaOCl extrusion. NP produced least NaOCl extrusion as compared to the other three systems. Due consideration should be given to the potential for apical extrusion of the irrigant before the selection of an irrigation system.

Retrieval of Separated Intracanal Endodontic Instruments: A Series of Four Case Reports

The separation of an endodontic instrument during a root canal procedure is one of the most common endodontic mishaps. Separation of endodontic instruments may block access to the apical portion of the root and hamper the disinfection process. It obstructs the appropriate debridement of the canal apical to the fragment, jeopardizing the treatment's outcome. However, due to the advancements in the methods and armamentarium, the effective retrieval of a separated instrument (SI) from the root canal has become possible. This paper includes a case series of management of separated instruments whereby SI was successfully removed in four cases. The instruments were separated intracanal at various levels in the middle and apical third of maxillary and mandibular molar teeth. The level of separation was located, staging performed, and SI was removed using an ultrasonic device under magnification. Removal of the SI was followed by obturation till the entire working length and subsequent post-endodontic restoration. Patient satisfaction with treatment outcomes in all cases was good. Case evaluation, good armamentarium, adequate knowledge along with good clinical skills and experience aid in the successful retrieval of separated instruments. Removal of the instrument without further damage to radicular dentin is important to maintain the integrity of the tooth.