Evaluation of fracture resistance of pulpotomized second primary molars restored with fiber-reinforced composite

Objectives: Fiber reinforcement of composite restorations can help decrease the fracture risk in restored pulpotomized teeth with severe coronal lesions. This study aimed to evaluate the fracture resistance of pulpotomized second primary molars restored with fiber-reinforced composite (FRC). Methods: This experimental study was done on 40 extracted primary second molars in four groups (n = 10). The negative controls were intact untreated teeth; while, other samples were pulpotomized with the mesio-occlusal-distal (MOD) access cavities prepared on their buccal and lingual surfaces. Positive control group was left unrestored. Composite group received glass ionomer on Zonalin and was restored with flowable composite and then composite. The FRC group received glass ionomer as the preceding group; the glass fiber was embedded within flowable composite, and the cavity was restored with composite. The compressive forces leading to fracture were recorded in Newton. Comparisons were made through one-way ANOVA and Tukey's post-hoc test (alpha = 0.05). Results: The highest mean fracture resistance belonged to the intact teeth (604.45 59.02 N), then the FRC group (584.31 +/- 57.18 N). Unrestored teeth had the lowest fracture resistance (235.60 +/- 45.60 N); however, they were not significantly different from composite group in this regard (P = 0.47). Although FRC group had significantly higher fracture resistance than the unrestored and composite group, it was not significantly different from intact teeth. Conclusions: Fiber reinforcement improved the fracture resistance of pulpotomized primary molar with large MOD cavities. (c) 2020 Japanese Society of Pediatric Dentistry. Published by Elsevier Ltd. All rights reserved.