The Comparative Evaluation of the Post-Antimicrobial Effect of MTAD ® and 2% Chlorhexidine against Enterococcus faecalis of Permanent Teeth with Necrotic Pulp

Comparative Evaluation of Residual Antibacterial Substantivity of Chlorhexidine, MTAD and Chitosan Against Enterococcus Faecalis in Human Root Dentin - An In vitro Study

Introduction

Complex anatomy of the root canal system results in incomplete debridement with mechanical instrumentation, leaving some areas or root canal walls untouched. There comes the significance of endodontic irrigants with residual antibacterial substantivity which prolongs the post-antibiotic effect, thereby improving the success and predictability of endodontic treatment.

Aim

To comparatively evaluate the residual antibacterial substantivity of 2% chlorhexidine, Biopure MTAD and 2% chitosan against Enterococcus faecalis at intervals of 1, 14 and 28 days.

Materials and Methods

Seventy-five therapeutically extracted permanent single rooted mandibular premolars teeth were selected. Dentin blocks of 4 mm thickness were prepared and enlarged to 1.6 mm. The autoclaved blocks were inoculated with 24-hour colonies of pure cultures of E. faecalis for 14 days. After the contamination period, canals of each dentin block were irrigated with 5 ml of sterile saline and dried with sterile paper points. A total of 75 dentin blocks were randomly divided into five groups as follows: Group A (21 specimens): 2% chlorhexidine, Group B (21 specimens): Biopure MTAD, Group C (21 specimens): 2% chitosan, Group D (6 specimens): positive control (infected dentin tubes) and Group E (six specimens): negative control (sterile dentin tubes). Then, the lumens of dentin blocks were irrigated with the respective irrigants for 10 mins and were dried using sterile paper points. The specimens were then incubated at 37°C for 28 days to maintain humidity. At experimental intervals of 1, 14 and 28 days, dentin shavings were removed from the canals of respective groups by circumferential filing with sterile no. 35 Hedstrom files. The powdered dentin samples obtained with each dentin block were observed for colony forming units (CFUs) using a Digital Colony counter and were expressed as CFUs/mL.

Result

All the irrigants in the study showed a significant decrease in CFUs from day 1 to day 28 indicating that they have residual antibacterial substantivity against E. faecalis. Group B (Biopure MTAD) showed significantly least mean CFUs compared to Group A (2% CHX) and Group C (2% chitosan) against E. faecalis at B1(day 1), B2(day 14) and B3(day 28). Group A (2% CHX) showed significantly higher mean CFUs than Group C (2% chitosan) at A1(day 1). Group C (2% chitosan) showed significantly higher mean CFUs compared to Group A (2% CHX) at C2(day 14) and C3 (day 28).

Conclusion

MTAD showed statistically higher residual antibacterial substantivity against E. faecalis at experimental periods of 1, 14 and 28 days. The residual antibacterial effect of 2% chitosan was better compared to 2% CHX at day 1. The residual antimicrobial substantivity of 2% CHX was higher compared to 2% chitosan at intervals of 14 and 28 days.

Comparison of antimicrobial efficacy of Calcipex and Metapex in endodontic treatment of chronic apical periodontitis: a randomised controlled trial study protocol

INTRODUCTION

Various intracanal medicaments have been used in cases of chronic apical periodontitis for appropriate disinfection of the root canal system to eliminate microbes especially from the inaccessible areas. Calcium hydroxide is the most common intracanal medicament available in various forms, but its effectiveness with or without iodoform using microbial culture is unknown. Therefore, our aim is to compare the antimicrobial efficacy of Calcipex and Metapex in endodontic treatment of teeth presenting with chronic apical periodontitis by assessing the bacterial load reduction.

METHOD AND ANALYSIS

60 single rooted teeth of patients with diagnosis of chronic apical periodontitis will be selected and the canals debrided chemomechanically. The patients will be randomised into two groups: Calcipex and Metapex. The first sample (S1) for bacterial culture will be taken before placement of intracanal medicament and the second sample (S2) will be taken after 7 days, before final obturation from the canal and sent to lab for culture. Colony-forming unit will be evaluated. Paired t-test will be used to assess difference between antimicrobial efficacies within the group of medicaments. Independent sample t-test will be used to assess antimicrobial efficacies between groups. Level of significance will be kept at 0.05.

ETHICS AND DISSEMINATION

Approval from Aga Khan University Hospital Ethical review committee is taken. Findings will be reported according to the Standard Protocol Items for Randomised Trials guidelines. Research findings will be disseminated through annual reports, peer-reviewed journals and conferences.

TRIAL REGISTRATION NUMBER

NCT04336709.