Adaptation between Bulk-fill and Traditional Multi-Increment-Fill Resin-based Composite Materials - Thesis Example

Recently, many resin-based composite materials have been introduced to the market allowing for use of the bulk-fill technique that is easier, time-saving, and may result in fewer voids in the bulk of material when compared to the incremental placement technique. Furthermore, several manufacturers claim that bulk-fill materials have lower polymerization-induced shrinkage stress than traditional increment-fill materials, which may produce better internal adaptation between the restoration and tooth. The alternative hypotheses are that there will be a difference in the internal adaption of the new bulk-fill resins placed in bulk compared to a traditional resin placed incrementally, both before and after aging. Seventy extracted human molar teeth will be sectioned to remove the cusp tips and the root portions leaving the central area enamel intact.

Then a Class I cavity will be prepared on each tooth. The teeth will be randomly and equally distributed into five experimental groups. Four groups will be restored with different resin-based composite systems using a bulk-fill technique. The fifth group is the control and will be restored with the multi-increment-fill technique. Each group will be divided randomly into two groups. The first group will be used as the control and the other will be used as the experimental group which will be the thermocycler.

Then, each tooth will be sectioned occlusogingivallyfrom the mid-mesial to the mid-distal surface of the cavity to obtain two 4 mm thick samples. Digital images from all specimens will be recorded and analyzed and the presence and dimension of gaps will be measured. Data will be analyzed using ANOVA with a 5 % significance level. Because of their numerous advantages, resin-based composite (RBC) materials have been widely used in dentistry since their development in the late 1950s. Besides their esthetic properties that mimic natural teeth, this type of restorative material is considered one of the most conservative filling materials, which does not require removing healthy tissues to obtain retention.