Introduction: While poor oral hygiene has been previously associated with an increased risk of nonalcoholic fatty liver disease (NAFLD), its association with hepatic fibrosis remains unclear. Here, we sought to analyze if toothbrushing frequency, an easy-to-assess indicator of oral health habits, would be associated with liver stiffness measurement (LSM) by transient elastography (TE) in patients with an established diagnosis of NAFLD. Methods: In this registry-based study, LSM was measured in 1,156 patients with NAFLD and analyzed in relation to the self-reported daily frequency of toothbrushing. LSM values ≥12 kPa were considered indicative of cirrhosis. Results: A trend toward a stepwise decrease (cross-sectional p = 0.13) in LSM was found in patients who reported having their teeth brushed more frequently: less than once a day (10.6 ± 8.6 kPa; 13% of the study sample), once a day (9.95 ± 8.40 kPa; 40%), twice a day (9.21 ± 7.63 kPa; 43%), and after every meal (8.91 ± 5.30 kPa; 4%). Patients who brushed their teeth less than once a day had a significantly higher prevalence of LSM values ≥12 kPa ( p < 0.05). In multivariable logistic regression analysis, the association of LSM values ≥12 kPa with toothbrushing habits remained statistically significant for less than once a day (odds ratio = 1.69, 95% confidence interval = 1.07−2.66, p = 0.02) with reference to twice a day or after every meal. Conclusion: Among patients with NAFLD, there is an independent association between brushing teeth less than once a day and TE-established cirrhosis.