Several factors in the pathophysiology of obstructive sleep apnea (OSA) may increase the likelihood of excessive occlusal loads. Increased occlusal loads may compromise a tooth’s mechanical resistance. This prospective controlled study assessed the frequency of OSA in patients presenting with tooth fracture. Patients with and without tooth fractures were selected in a consecutive manner from a private dental clinic between February 2018 and January 2020. Demographic and dental variables were registered. A parafunctional habits questionnaire, anthropometric measurements, and validated respiratory polygraphy were performed. Descriptive, comparative, and correlation statistical analyses were performed. Multiple regression analysis was also performed. Fifty-nine patients were included, and 29 presented tooth fracture. Patients with a tooth fracture formed the case group and patients without tooth fracture formed the control group. Patient age was significantly higher in the case group (59 ± 13 years) compared to the control group (44 ± 11 years). Most of the fractured teeth were molars, had a natural tooth as an antagonist, and were not endodontically treated. Twenty-one patients had OSA (apnea-hypopnea index: ≥ 5 events per hour) in the case group compared with 12 patients in the control group (P = .027). Moreover, the patients in the case group had a significantly higher apnea-hypopnea index (P = .000). Multiple regression analysis showed that only age had a significant effect on tooth fracture (P = .002). However, there was a statistically significant relationship between OSA and the presence of tooth fracture in patients aged ≥ 40 years (P = .041). OSA was more frequent in patients presenting with tooth fractures.
