# Effect of Spatial Orientation of Fibers on Fracture Resistance of Large Mesio-Occluso-Distal Cavities in Maxillary Premolars: An In Vitro Study

## TL;DR

This study shows that inserting fibers in a horizontal direction increases the fracture resistance of dental restorations in maxillary premolars.

## Contribution

The study introduces a novel comparison of fiber orientations to enhance the durability of dental restorations in large cavities.

## Key findings

- Horizontal fiber placement (Group A) showed the highest fracture resistance (910.58 N).
- Group E (no fibers) had the lowest fracture resistance (549.25 N).
- Fiber reinforcement significantly improved fracture resistance compared to non-reinforced restorations.

## Abstract

Aim: The aim of this study is to determine the outcome of fiber insertion on the fracture resistance of composite restoration in wide mesio-occluso-distal (MOD) cavities in maxillary premolars.

Materials and methods: After selection of 60 extracted maxillary premolars, large class two MOD cavities were prepared, and samples were divided into five groups (n=12) for insertion of polyethylene fibers. In group A, fibers were placed horizontally in the mesiodistal direction, while in group B, they were placed buccolingually. In Group C, they were placed in a U-shaped design, in Group D, it was placed in a circular orientation, and in Group E, there were no fibers. After the completion of the composite restoration and incubation process, the samples were tested under a universal testing machine at a crosshead speed of 1mm/min to measure the fracture resistance of all the samples, and the values were obtained in Newton (N).

Results: The fracture resistance was highest in Group A (910.58 N), followed by Group C (898 N), Group B (894.33 N), and Group D (753.08 N). Group E (without fiber) showed the least fracture resistance value (549.25 N).

Conclusion: Fiber reinforcement significantly improves the fracture resistance in maxillary premolars, with Group A having superior results as compared to others in the present study.