Clinical Evaluation and Antimicrobial Effect of Papain Based Chemo-mechanical Caries Removal Agents

All the lesions in the children's oral cavity indicated for treatment will be treated and sampled for microbiological analysis prior to and following caries removal. On the day of the intervention, the children will be asked to refrain from tooth brushing in the morning, as well as eating and drinking (except water) for at least two hours before the appointment. The patients will be instructed to rinse with a cup of water, then the outer surface of the carious lesion will be washed with a flurry of water to avoid contamination of plaque bacteria. The tooth will then be partially isolated using cotton rolls and saliva ejector. Two portions of dentin will be collected with sterile excavators from the middle of the cavity to perform the microbiological analysis of each tooth before and then after caries removal procedure. The dentin sample will then be inserted in a sterile test tube containing 1 mL of saline and transported to the microbiology laboratory within 1‐2 hours. The bacterial count obtained for a given amount of dentin will be used to estimate the number of colonies present in 1 mg dentin (CFU/mg). In the CMCR group: either Papacarie duo or Brix 3000 gel will be applied on the carious lesion of tooth and left undisturbed for 30‐60 seconds, following manufacturer instructions This produces softening of carious dentin, which will be removed with a hand excavator. This step will be repeated 2‐3 times until dentin demonstrates slight resistance with no tug‐back sensation when tested with an exploratory probe while pressing an explorer into dentin, then the application of the chemo‐mechanical agents will be stop The visual test for assessment of complete caries excavation will be based on non‐turbid appearance of the CMCR agent used. In the ART group hand excavation will be performed to remove the carious tissue from the cavity by using a sterile sharp hand excavator. The cavity will be determined to be caries‐free according to visual and tactile clinical criteria. No local anesthesia will be administered as it would alter the pain perception of the patient unless necessary.