The aim of this study is to assess the postoperative pain following restoration with composite resin versus sonic fill in children with deep carious first permanent molar.

For many years, composite resin restorations have been considered an acceptable treatment choice for anterior applications. Recent advances in composite resin mechanical properties and improved adhesive systems have broadened the application of these materials to include the restoration of posterior teeth. However, it is still generally accepted that posterior composite resin restorations have limitations and that there is no ideal material available. A volumetric shrinkage occurs when a composite resin material is cured. The shrinkage is the result of conversion of monomer molecules into a more dense polymer network, which leads to bulk contraction. A new nanohybrid composite activated by sonic energy has been recently introduced as a single-step, bulk-fill restorative material. This system utilizes the patented sonic-activation technology enabling a rapid flow of composite into the cavity for effortless placement and superior adaptation in one single layer, thereby, emphasizes its practical and efficient technique for placing posterior composites. The hand piece, designed by KaVo (Germany), delivers sonic energy at varying intensities, which is adjusted on the shank from low to high (1 to 5) to control rate of composite extrusion.

Inclusion Criteria:

• Asymptomatic First Permanent Molar
• Age of the patient ranging from 6-9 years
• Normal periodontal status
• Teeth with no previous restorative treatment
• Good oral health
• Absences of pathological mobility

Exclusion Criteria:

• Adverse medical history
• Potential behavioral problems
• Parents refusing participation of their children