Objective: Hand washing is the most important way to prevent the spread of infection. However, studies have shown that there is a lack of knowledge among physicians about proper hand hygiene. The purpose of this study was to determine the knowledge of general dentists and dental specialists regarding the correct agents to use and the appropriate times to wash hands. Method and Materials: A questionnaire asking for demographic information and the answers to questions about proper hand hygiene practices and agents was sent via email to a list of general dentists and dental specialists. A total of 480 completed surveys were received (approximately 15% response). Results: None of the respondents answered all the questions correctly. Six percent answered 4 questions correctly, 23% answered 3 questions correctly, and 47% answered only 2 questions correctly. There was no correlation between the number of correct answers and whether the respondent was a general dentist or a specialist. Conclusion: There is a lack of knowledge among dentists regarding proper hand hygiene. For the benefit of both the patient and the doctor, this situation must be remedied. Schlagwörter: hand hygiene, hand washing, hand washing agents