# Comparative evaluation of human ß defensin-2 in GCF and microbial flora in subgingival plaque among patients treated with conventional orthodontic braces and aligners: a prospective clinical study

## TL;DR

This study compares levels of hBD-2 and harmful bacteria in the gums of patients using orthodontic braces versus aligners.

## Contribution

The study provides new insights into the impact of orthodontic treatment types on immune markers and microbial flora in the gums.

## Key findings

- hBD-2 levels were significantly higher in the conventional braces group at T2 and T3.
- Conventional braces showed higher presence of harmful bacteria compared to aligners at T1, T2, and T3.
- Both hBD-2 and bacterial levels increased over time in both groups, with the highest at T3.

## Abstract

The aim of this study was to compare the presence of human ß defensin-2 (hBD-2) in GCF and microbial flora in the subgingival plaque, among the patients treated with fixed orthodontic braces and aligners.

Samples of GCF and subgingival plaque were collected from 170 patients (85 conventional metal fixed appliance and 85 aligner patients) at T0 (baseline), T1 (14 days), T2 (1 month) and T3 (3 months). The GCF sample was analyzed for the presence of hBD-2 using ELISA. The subgingival plaque sample was analyzed for the presence of Porphyromonas gingivalis, Prevotella intermedia, Actinobacillus actinomycetemcomitans, and Treponema denticola using RT-PCR. For statistical analysis, intergroup comparison was done using independent z-test, to compare the presence of hBD-2, as well as the microbial flora. Repeated measure ANOVA with post-hoc analysis was done to evaluate hBD-2 and subgingival plaque at different time periods.

On intergroup comparison, the presence of hBD-2 was found to be significantly (p≤0.05) greater at T2 and T3 in the conventional than in the aligner group. The presence of the aforementioned bacteria was found to be significantly (p≤ 0.05) greater at T1, T2 and T3 in the conventional braces group than in the aligner group. On intragroup evaluation, for both the parameters, the minimum value was seen at T0 and the maximum, at T3 for the conventional and aligner groups.

The levels of hBD-2 and subgingival bacteria was found to be greater in the conventional group than the aligner group.