Postoperative Pain After Conservative Root Canal Preparation

The goal of this clinical trial is to compare the pain experienced by healthy participants after root canal treatment with small versus large root canal sizes. The main questions it aims to answer are: 1. Do small and large root canal sizes cause different pain levels? 2. What is the number of painkiller pills taken by each participant? 3. Does small root canal size cause severe pain and facial swelling? The researcher will perform root canal treatment on lower molar teeth. The researcher will ask about the pain level, painkiller pill number, and swelling on the 6th,12th, 24th, 48th, 72nd hours, and 7th day after the treatment.