Comparative evaluation of microbial load reduction and post operative pain assessment of antimicrobial peptide GH12 and chlorhexidine as root canal irrigants-A randomised controlled trial

OBJECTIVES

To evaluate and compare the efficiency of antimicrobial peptide GH12 and chlorhexidine as final root canal irrigants in

a) microbial load reduction

b) postoperative pain assessment.

HYPOTHESIS

There is no difference in microbial load reduction and postoperative pain (if any) between GH 12 and chlorhexidine when used as final root canal irrigants.

MATERIAL AND METHODS RESEARCH DESIGN

The proposed study will adopt a two-arm parallel, double-blinded, randomized controlled trial.

STUDY SETTING

Patients attending the outpatient department of Conservative Dentistry and Endodontics, SCB Dental College and Hospital, Cuttack, Odisha, will be recruited into the study based on the inclusion and exclusion criteria.

ETHICAL CLEARANCE was obtained from the Institutional Ethical Committee.

INFORMED CONSENT will be obtained from every participant after explaining the study criteria.

 PROTOCOL TO BE ADOPTED FOR THE PROPOSED STUDY

Sample size calculation:

Calculations to determine the sample size were performed using G* power software. The calculations were based on an assumed effect size of 0.9821, an alpha level of 0.05, and the desired power of 80%. The estimated sample size was 36. Considering a 10% loss of follow-up, 40 subjects (20 in each group) will be included in the study.

Statistical tests:

The collected data will be subjected to statistical analysis using the Statistical Package for the Social Sciences (SPSS) version 29.0 (IBM Corporation, USA). The normality of the data will be checked using the Shapiro-Wilk test. Descriptive analyses will be done. For intragroup comparisons, a paired sample t-test or Wilcoxon signed-rank test will be used. For intergroup comparisons, an independent sample t-test or Mann-Whitney U test will be used. P-value less than 0.05 will be included in the study

TREATMENT PROCEDURE:

The patient will be randomly divided (using randomiser software) into two groups (I &II) (n=20) according to the final irrigation solution to be used.

All endodontic procedures will be performed by one endodontist under strict aseptic conditions with local anaesthesia (2% lidocaine & epinephrine at 1:80,000) and rubber dam isolation.

The access cavity will be prepared, and straight-line access to the canal will be obtained.

After accessing the pulp chamber, the root canal will be explored with a size 10K file

Working length will be determined with the help of an electronic apex locator and confirmed radiographically.

Patency will be verified with size 20, 0.02 taper K-file to ensure that the sterile paper-points will reach the sampling site.

SAMPLE 1 (S1)

3 sterile absorbent paper points (ISO #20/2%) inserted along the entire length of the root canal, remaining in position for 60 seconds

If the root canal was dry, it was moistened with sterile saline solution to ensure a viable specimen.

After sampling, points were immediately placed into a Cryotube containing Phosphate Buffer solution and stored at  -20 °C & subsequently sent for RT- PCR analysis.

 Root canal instrumentation will be performed using rotary instruments & the canal will be irrigated with 2ml of 3% NaOCl solution using 30G side-vented needle after each instrumentation and rinsed using 5ml of sterile saline solution.

For smear layer removal, 2 mL of 17% EDTA will be added inside the root canal and activated for 30 s. The root canal will be refilled with 17% EDTA and activated for another 30 s.

Patency will be verified with a size 20, 0.02 taper K-file to ensure that the sterile points will reach the sampling site.

SAMPLE 2 (S2):

S2 will be collected using sterile absorbent paper points (size 20) inserted along the entire length of the root canal, remaining in position for 60 seconds.

If the root canals are dry, they will be moistened with sterile saline solution to ensure a viable specimen.

Upon withdrawal from the root canal, points will be immediately placed into a Cryotube containing Buffer solution and stored at -20 °C & will be sent for RT PCR.

In group I, 5ml of GH12 (3.2mg/100ml) will be used as the final irrigant.

In group II, 5ml of 2% CHX will be used as the final irrigant.

  SAMPLE 3 (S3):

S3 will be collected using the same methods as S1 after final irrigation in both groups.

Upon withdrawal from the root canal, the paper point will be immediately placed in a Cryotube containing Buffer solution and stored at -20 °C & will be sent for RT-PCR analysis.

 The root canals will be dried with absorbent paper points and the access cavity will be sealed with 2mm of temporary material and Glass Ionomer Cement. During the second visit, after 7 days, the canal will be obturated with gutta-percha points and resin-based sealer. The teeth will be restored with composite resin. Postoperative intraoral periapical radiographs will be taken immediately after obturation.

 POST-ENDODONTIC PAIN ASSESSMENT

The degree of post-endodontic pain will be measured using an 11-level numeric rating scale (NRS) at 24, 48, and 72 h and 5th day. Number 0 represents no pain and number 10 represents the most pain.