Comparing the Effect of Low Level Laser Therapy and Intracanal Cryotherapy on Post Operative Pain following Single-Visit Nonsurgical Endodontic Treatment of Mandibular Molars with Irreversible Pulpitis and Apical Periodontitis a Randomized Clinical Trial

This is an in vivo experimental, prospective, double blinded randomized controlled trial. Participants in each group will be allocated by Lottery system. The candidate under supervision will be responsible for providing allocation and division of patients into three groups and save the data until the date of performing the procedure. Group 1 Single-visit root canal treatment followed by Low-level Laser Therapy, Group 2 Single-visit root canal treatment with adjunctive Intracanal Cryotherapy, Group 3 Single-visit root canal treatment followed by neither of the adjunctive modalities (Control group). The outcome assessors and the participants will be blind (double blinded) to the procedure while the operator (the researcher) will not be blinded owing to the difference in the modalities employed for the treatment and variations in the steps involved while performing the procedure. Detailed history would be recorded and subjective and objective assessment of teeth requiring endodontic treatment will be done using 170 mm Heft Parker Visual Analogue Scale. The patient will be explained about the treatment, the alternative treatment and the risks involved and an informed consent will be given to the patient which will be signed by the patient giving the consent. Only the patients giving their consent for the clinical trial will be included in the study and will randomly be divided into three groups (the three groups will be standardized in terms of age, gender, type of tooth, root curvature and severity of pain before treatment) by Lottery method and be scheduled for single-visit root canal treatment. The procedure will be started with administration of local anaesthesia. After achieving adequate anaesthesia, rubber dam isolation will be performed and an access cavity will be prepared using a round bur and high-speed hand-piece under water and air spray. Class 2 cavities will be converted into Class 1 cavities by doing Pre-endodontic build-up. After performing patency filing, the working length of the canals will be determined using Root ZX apex locator (J Morita), which will be confirmed by digital radiography. The root canals will be prepared using Rotary System as per apical constriction and initial binding file and biomechanical preparation will be completed using crown-down method. Standard Irrigation protocol will be followed for all the groups. A final rinse will be performed with saline at room temperature. (Saline at a temperature of 2.5 degree Celsius will be used as a final irrigant in Intracanal Cryotherapy group). The root canals will be dried with sterile paper points and filled with gutta-percha and Bioceramic root canal sealer (Bioactive Root Canal Sealer, Safe Endo) with warm vertical compaction technique (Orikam Fast pack and Fast fill devices) in the same session; the quality of obturation would be checked by taking final Intaoral Periapical Radiographs.  The teeth will be disoccluded and post endodontic restoration will be completed. After the completion of single-visit endodontic procedure following the above mentioned protocol. The first group will be subject to Low-level Laser Therapy by laser irradiation performed using 980-nm diode laser (Rise Medicare) 0.5 W power and a tip diameter of 10 mm for 15 seconds. The laser will be irradiated to the soft tissues covering the mesial and distal apices of the tooth from buccal as well as lingual sides for 15 seconds at each site with the tip of the laser handpiece held at a distance of approximately 10 mm from the mucosa. The fibre tip of the laser will be positioned perpendicular to the surface and close to the soft tissue. The study participants will be assessed for the intensity of pain experienced at 6, 12, 24, 48 and 72 hours postoperatively using a Heft-Parkar visual analogue scale (VAS) and a patient questionnaire which will include the duration to which pain lasted, the number of medications patient had required to take to relieve pain or any other complains related to the tooth, wherein telephonic evaluation of postoperative pain will be done by contacting through phone on specific hours and days and a second appointment will be scheduled for follow-up visit 72 hours post-operatively; when the patient will be assessed clinically to check for intra-oral complications and percussion test will be done to check the periapical status.