Materials and Methods: The sample of study consisted of 15 patients; each one has four molars at least with type I caries. The patients were divided into four groups: Group A includes molars restored with Composite, Group B: molars restored with Giomer, Group C: molars restored with Compomer, and Group D: molars restored with RMGIC, no matter that they are maxillary and mandibular molars. Class I cavity was prepared with specific dimensions on the occlusal surface only. The cavities in Group A were restored with Nano hybrid composite (Tetric Evo Ceram, Ivoclar Vivadent, Ellwangen, Germany) while those in Group B were restored with Giomer (Beautifil II, Shofu, Japan), the cavities in Group C were restored with Compomer (Ivoclar) whereas those in Group D were restored with RMGIC (FUJI II LC,GC). Post-operative sensitivity has been evaluated during different follow-up periods: 3 days, 7 days, 3 weeks and 7 weeks, using the Visual Analogue Scale (VAS).

Results: No statistical difference was observed between Beautifil II, Tetric Evo Ceram, Compomer and RMGIC restorations in terms of post-operative sensitivity during the follow-up periods.