The hall technique for primary teeth depends on the idea of isolation of the carious non exposed primary tooth from all bacteria present in the oral cavity by using a stainless-steel crown which result in arresting of the caries and preventing its progress to the pulp. Recently laser and Silver Diamide Fluoride (SDF) have been used to arrest the progress of caries so in the current study we will compare the success rate of hall technique with either laser or SDF in arresting of caries

The high frequency of caries in primary teeth and its inadequate treatment are major public health problems during childhood. Nowadays, the Hall technique is one of the methods used for biological sealing in carious lesions in primary molars. Thus, the bacteria will be sealed from oral environment and the caries will be inactive. Using the Hall technique, the crown is placed without local anesthesia, caries removal, or tooth preparation. Then, the crown is fitted over the carious primary molar by either the dentist's finger pressure, or the child's biting force. The average results of many clinical trials showed that the success rates of the Hall technique were greater than the conventional restorations. However, some criteria of minor failures were seen in 26.6% of Hall crowns. Silver diamine fluoride (SDF), a clear liquid that combines the antibacterial effects of silver and the remineralizing effects of fluoride, is a promising therapeutic agent for managing caries lesions in young children, its effectiveness in reducing specific cariogenic bacteria and its remineralizing potential on enamel and dentin have been reported in many studies. Recently, lasers have been proven to significantly arrest the dental caries by increasing the acid resistance of the enamel with an antibacterial effect. Diode lasers with several positive aspects, such as the small size, low cost, and ease of use in the oral cavity, were found to have a caries prevention and arrest effect on the dental enamel, particularly deciduous teeth. In the current study the success rate of Hall technique using SDF will be compared to the same technique using Diode laser in arresting the carious lesions in primary teeth.

Inclusion Criteria:

• Patients should be medically free
• Presence of asymptomatic enamel and dentin caries in one or more primary molars, which can be detected clinically and radiographically
• Periapical radiograph should show caries involving the outer half of the dentin
• There should be no signs or symptoms of pulpal pathosis

Exclusion Criteria:

• Immunocompromised patients
• Presence of any signs or symptoms of pulpal pathosis denoting irreversible pulpitis
• Parents who are not willing to come in the follow up visits