Cairo University

A randomized clinical trial used light curing posterior bulk-fill universal shade composite, universal adhesive bonding agent, and 37% phosphoric acid etchant gel. The study, approved by the Research Ethics Committee of Faculty of Dentistry, Cairo University, involved 84 participants aged 20-45 with class II cavities. The trial, registered on ClinicalTrials.gov, compared non-heated bulk fill resin composite with preheated resin composite in four groups, with varying heating cycles. The study followed CONSORT guidelines and assessed restoration performance using modified USPHS criteria over 24 months, with statistical analysis conducted using R software.