# The effect of the COVID-19 pandemic on orthognathic surgery in Sweden - a registry-based study

## TL;DR

The study found that orthognathic surgery in Sweden decreased significantly during the pandemic, with university hospitals being more affected than regional hospitals.

## Contribution

This is the first registry-based study in Sweden analyzing the impact of the pandemic on orthognathic surgery across different hospital types.

## Key findings

- Orthognathic surgery volume dropped significantly during the pandemic compared to pre-pandemic levels.
- University hospitals experienced a larger relative decrease in surgeries than regional hospitals.
- Post-pandemic surgery volumes returned to pre-pandemic levels without significant differences.

## Abstract

The COVID-19 pandemic had a noticeable impact on healthcare services. The restrictions imposed during the pandemic where extensive, and in Sweden, elective surgery was deprioritized to make room for the most severely affected patients. This study aimed to evaluate the effect of the COVID-19 pandemic on the volume of orthognathic surgery (OGS) in Sweden, and to compare the impact between regional and university hospitals.

This registry-based study used national data from the National Quality Registry for Orthognathic Surgery (NROK). OGS performed during 2018–2022 and registered in NROK were included. The follow-up time was divided into three time periods: pre-pandemic, pandemic and post-pandemic. Of 21 hospitals performing OGS in Sweden, 18 (11 regional and seven university hospitals) were included in the final analysis. Differences in national monthly means were analyzed using one-way ANOVA and Kruskal-Wallis tests, with post hoc comparisons. Linear regression was used to assess differences in trends between hospital types.

The national monthly mean of OGS was significantly lower during the pandemic compared to both the pre-pandemic period (− 13.7 surgeries, 95% CI: 3.6–23.8; p < 0.01) and the post-pandemic period (− 15.6 surgeries, 95% CI: 2.6–28.7; p < 0.05). University hospitals experienced a 40.7% reduction in surgeries during the pandemic (p < 0.001), whereas the reduction at regional hospitals (− 19.7%) was not statistically significant (p = 0.603). No significant differences were found between the pre- and post-pandemic periods, neither in national monthly means nor when comparing hospital types.

A significant decrease in the number of OGS was observed during the pandemic in Sweden. No statistically significant difference was found between the pre- and post-pandemic periods, suggesting a meaningful normalization in the frequency of OGS in Sweden following the pandemic, although not accounting for possible surgical backlog. University hospitals appeared to experience a greater relative decrease in surgical volume during the pandemic compared to regional hospitals. This difference may be attributable to lower baseline volumes at regional hospitals rather than a differential impact of the pandemic itself.