1.Evaluation of internal adaptation of flowable and bulk-fill resin-based composites
Christina Maria Noel ; Nor Suhana Azni Satapa ; Noor Azlin Yahya ; Ros Anita Omar
Annals of Dentistry 2021;28(1):23-31
This study aimed to evaluate and compare the internal adaptation of bulk-fill resin-based composite restorative
materials with flowable composites as lining materials using self-etch adhesive system. Class I cavities
(2mmx4mm) were prepared on flattened occlusal surfaces of fifty extracted human premolars and randomly
assigned into five groups (n=10) according to the materials used: Beautifil Bulk-fill Restorative (BR); Beautifil
Bulk-fill Flowable (BF); Beautifil Flow Flowable F10 (BF10); and Self-etch adhesive (SEA). Group A: SEA+BR;
Group B: SEA+BF10+BR; Group C: SEA+BF+BR; Group D: SEA+BF10+SEA+BR and Group E: SEA+BF+SEA+BR. The
samples were thermocycled for 500 cycles, then sectioned mesiodistally, polished and pre-treated prior to
scanning electron microscopy (SEM) evaluation. From SEM images, measurement of adhesive and cohesive
adaptation failures was recorded at multiple sites of the pulpal floor and in between materials. Data were
analysed using one-way ANOVA and post-hoc Tukey tests (p<0.05). Cohesive failure in SEA was observed at the
pulpal floor with the lowest percentage in Group A (5.14%), and highest in Group C and E (>16%). However,
there were no significant difference among all groups. Adhesive failure was seen at the pulpal floor between
SEA+BF/BF10/BR and between SEA+dentine with the highest percentage of gaps formed in Group A between
SEA+dentine (6.62%) and SEA+BR (5.30%). Nonetheless, no significant differences were observed among all
groups with p=0.89 and p=0.70, respectively. With the use of BF/BF10 at the pulpal floor, adhesive failure was
reduced but resulted in increased of cohesive failure. However, both adaptation failures were absent between
materials (BF/BF10 and BR) regardless with or without application of SEA.