Our study evaluated and compared the postoperative sensitivity of the placement technique (incremental and bulk fill) in class II posterior composite resin restorations bonded with two different adhesive strategies (self-etch and etch-and-rinse).Sixty patients were randomly selected, their age range from 25 to 40 years old. They were divided into 2 main groups according to the packing technique of composite material; incremental Tetric Evoceram and Tetric Evoceram bulk fill composite.30 patients (n=30) were selected for incremental Tetric Evoceram composite restorations and they were equally divided according to the adhesive systems used (etch and rinse or self-etch adhesive strategy) (n=15 teeth).30 patients (n=30) were selected for Tetric Evoceram bulk fill composite restorations and they were equally divided according to the adhesive systems used (etch and rinse or self-etch adhesive strategy) (n=15 teeth).Post-operative pain assessed at 24 hours, 1 week and 1 month using the visual Analog Scale Score (VAS).Each patient was instructed to place a vertical mark on the VAS line at home to indicate the intensity of pain at each assessment period.

Our results revealed that when the two composite types using self-etch adhesive system & total-etch adhesive system were evaluated; there was no statistically significant difference between the two composite types after 1 day, 1 week as well as 1 month.

When the two adhesive systems were compared using Bulk Fill composite & incremental Nano resin composite there was no statistically significant difference between the two adhesive systems after 1 day, 1 week as well as 1 month.

Using Bulk Fill composite with self-etch adhesive; there was a statistically significant decrease in prevalence of hypersensitivity after 1 week. There were no cases with hypersensitivity after 1 week as well as 1 month. Using Bulk Fill composite with Total etch adhesive; there was a statistically significant decrease in prevalence of hypersensitivity after 1 week as well as from 1 week to 1 month.

Using Incremental Nano resin composite with self-etch adhesive; there was a statistically significant decrease in prevalence of hypersensitivity after 1 week as well as from 1 week to 1 month. Using Incremental Nano resin composite with Total etch adhesive; there was a statistically significant decrease in prevalence of hypersensitivity after 1 week as well as from 1 week to 1 month.

Inclusion Criteria:

• Patients must show no signs of spontaneous dental or orofacial pain.
• The presence of molar and premolar class II teeth requiring composite restorations for the treatment of primary carious lesions
• The selected teeth should have an occlusal contact with natural or crowned antagonist teeth
• The selected teeth should have a proximal contact with the adjacent teeth.
• Shallow and mid-sized cavity depths will be included in the study .

Exclusion Criteria:

• Increasing pre-operative sensitivity of the selected teeth.
• Teeth with abnormal periapical anatomy or caries that will be likely to result in very deep restorations.
• Teeth with old restorations or severely destructed dental crowns.
• Teeth with spontaneous pain
• Tempro-mandibular joint problems involving symptomatic pain.
• Patients taking analgesics that could alter their normal pain perception level.
• Pregnancy or breast feeding, acute and chronic systemic diseases, immunecompromised patients.