Evaluation of Post-operative Sensitivity of Bulk Fill Resin Composite Versus the Nano Resin Composite.

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.

Eligibility Criteria:
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.