The Impact of Weather on Emergency Visits for Acute Endodontic Treatment—A Retrospective Time-Series Study

Background: This study examines the correlation between extreme weather events and acute endodontic treatment-related emergency visits (AET-related EVs). Methods: A total of 11,541 AET-related EVs at the Medical University Graz from January 2016 to August 2022 were analyzed using a distributed lag non-linear model. Extreme weather was defined as conditions beyond the 5th or 95th percentiles, and relative (RR) and cumulative risks (cRR) were assessed over 14 days. Results: High temperatures (>21 °C) increased AET-related EVs (cRR 1.41 [1.20–1.65], p < 0.001), while cold spells reduced cRR (0.81 [0.68–0.96], p = 0.014). Prolonged humidity around 65% raised cRR to 1.38 (1.21–1.59, p < 0.001). Heavy precipitation elevated cRR (1.24 [1.04–1.46], p = 0.016). Lower wind speeds were linked to a reduced cRR of EVs within four days following a single weather event (minimum of 0.86 [0.75–0.99], p = 0.032), and within four, seven and 14 days after prolonged low wind speeds (minimum of 0.69 [0.58–0.83], p < 0.001). Three-day low atmospheric pressure increased RR after seven days (1.04 [1.01–1.08], p = 0.014), while a single event reduced cRR by one day (0.78 [0.63–0.95], p = 0.016). Conclusions: Extreme weather events significantly influence AET-related EV rates, with various conditions affecting risk differently. Potentially causative pathophysiological mechanisms need to be researched.