To determine the knowledge of general dentists and dental specialists on temporomandibular disorders (TMD) in Italy, a web-based questionnaire including 20 multiple- choice questions was sent to all general dental practitioners and specialists in Italy. Mean score of diagnosis and treatment knowledge of all participants was 23.8 ± 7.3 out of 40 achievable scores. There was a significant difference between the knowledge of dentists and the variables of sex, age, and years of experience (p < 0.05). However, overall, it is not possible to state a significant difference between the final score of dentists with different specializations (p = 0.89). The results of this study showed an acceptable knowledge of participants regarding TMD.