This randomized clinical trial aims to compare the clinical and radiographic performance of four direct restorative materials used for restoring carious primary molars in children. Eligible children aged 4-8 years with posterior primary molars requiring direct restoration will be randomly allocated (1:1:1:1) to receive one of the following materials: an alkasite restorative material (Cention N), a self-cure bulk-fill resin composite (Stela; SDI), a conventional light-cured nanohybrid resin composite (Beautifil II), or a resin-modified glass ionomer cement (Riva Light Cure). Restorations will be evaluated using the Fédération Dentaire Internationale (FDI) World Dental Federation criteria. Postoperative sensitivity will be assessed at 48 hours using a 0-10 visual analogue scale (VAS). Clinical and radiographic follow-up assessments will be conducted at baseline and at scheduled recall visits

Inclusion Criteria:

1. Age 4-8 years old.
2. Primary molars indicated for restorative treatment.
3. No pulp involvement or history of dental pain.
4. Cooperative children (Frankl: +ve or ++ve).

Exclusion Criteria:

1. Pulp exposure after caries removal or clinical signs of irreversible pulpitis/necrosis.
2. Severe developmental enamel defects or insufficient enamel for bonding.

individual participant data will not be shared to protect participant privacy and confidentiality, in accordance with the informed consent provided by the participants and the ethical approval granted for this study

Outcome assessment was performed by a blinded assessor who was unaware of group allocation; operator blinding was not feasible due to differences in material handling.