# A comparative investigation of the quality of radiographs produced by portable handheld and fixed x-ray units

## TL;DR

This study compares the quality of dental X-rays taken with portable and fixed X-ray units, finding differences in brightness, contrast, and noise.

## Contribution

The study provides a direct comparison of radiographic quality between portable and fixed X-ray units using specific CMOS sensors.

## Key findings

- Handheld X-ray equipment produced radiographs with higher brightness and lower contrast than fixed equipment.
- Noise levels varied depending on the CMOS sensor used with the portable X-ray equipment.
- Uniformity of radiographs was not significantly affected by the type of X-ray equipment.

## Abstract

To evaluate the impact of handheld portable intraoral diagnostic X-ray equipment on radiographic quality and to compare their radiographs with radiographs obtained using fixed intraoral X-ray equipment. For brightness, noise, and uniformity, radiographs of an acrylic block were obtained with two complementary metal oxide semiconductor (CMOS) sensors (Digora Toto and Snapshot). Six radiographs for each sensor were obtained using the Eagle handheld portable X-ray equipment set at 60 kVp, 2.5 mA, and 0.45 s. Then, six radiographs were obtained with the Focus fixed X-ray equipment set at 60 kVp, 7 mA, and 0.16 s. Mean and standard deviation of the gray values were evaluated. For contrast, radiographs of an aluminum step-wedge were obtained using both sensors, X-ray equipment, and the aforementioned acquisition parameters. The percentage of contrast variation was evaluated. The comparison between the equipment was evaluated for its influence on radiographic quality using Student's t-test (p < 0.05). The handheld portable X-ray equipment produced radiographs with higher brightness and lower contrast regardless of the CMOS sensor used (p<0.0001). Noise levels were higher with the handheld portable X-ray equipment than with the fixed X-ray equipment using the Digora Toto system, and lower with the Snapshot system (p < 0.05). No significant differences were found for uniformity. Therefore, radiographs obtained with a handheld portable intraoral diagnostic X-ray equipment have higher brightness and lower contrast compared to those obtained with fixed X-ray equipment. While the effect on noise levels varies depending on the digital system used, the uniformity remains unaffected by the type of X-ray equipment.