Dental fear affects a considerable number of patients and is linked to avoidance of dental treatment, often resulting in pain and the need to undergo more invasive treatment when patients do come to the dentist . Further, the tendency to receive symptom-oriented treatment (rather than preventive treatment) is related to higher levels of dental fear, providing evidence for a "vicious cycle" in which dental fear continues to be predictive of avoidance, greater dental treatment needs, symptom-oriented care, and continued fear . When fearful patients do appear for dental treatment, they may pose special treatment considerations for the practitioner .
Clinicians and researchers alike have the need for valid measures of dental fear. Questionnaires have several advantages over other methods of assessing fear. First, they are quick and inexpensive to administer and score. Second, they have high face validity, making them appropriate tasks for patients and research subjects to engage in. Because of these qualities, several measures of dental fear have been developed for adult and child patients [3, 4].
Perhaps the two most frequently used adult questionnaire measures of dental fear and anxiety are the Dental Anxiety Scale [DAS; ] and the Dental Fear Survey [DFS; ]. Both were originally developed in English. The original DAS is a 4-item questionnaire, asking individuals to rate their anxiety as they imagine approaching four dental situations, such as sitting in the waiting room anticipating dental treatment. The Modified Dental Anxiety Scale [MDAS, ] was developed to improve the psychometrics and content validity of the original DAS by adding an item about receiving dental injections, and ordering the potential answers to each item so that they range from least to greatest level of anxiety [3, 4]. The MDAS has been found to be reliable and valid in several samples from England, Scotland, Wales, Ireland, Finland, Dubai, Brazil, and Turkey, as well as in a sample of Spanish-speaking individuals in the United States [7–12].
The original DFS contained 27 items , which the authors later reduced to 20 . The items assess a broader array of dental stimuli than the MDAS, such as seeing the drill, smelling the dental office, and the like. In addition, the respondent is asked to rate specific physiological responses to dental stimuli, such as muscle tension and increased breathing rates. Two items assess avoidance of dental appointments due to fear, and one item asks for an overall rating of fear of dental work. The DFS has been found to be reliable and valid in samples of college students and dental patients . The measure has been translated into a number of languages, including Danish, Swedish, Norwegian, Hungarian, Brazilian, Turkish, Spanish (for Hispanics in the United States), Castilian (Spanish spoken in Spain), Chinese and Malay versions [12, 14–21].
The criterion validity of the DFS has often been assessed by comparing groups of dental phobics with non-phobics, finding that phobics score higher than non-phobics [e.g., ]. Similarly, MDAS scores have been found to be higher in groups of dental phobics, compared with other individuals [e.g., ]. In situations where patients' classification as dentally phobic has not already been determined, alternate methods of validation have been used. For example, Corah compared patients' scores on the original DAS with independent dentists' ratings of the patients' anxiety during treatment .
Psychiatrists have noted that there may be cultural differences in the manifestation of various anxiety disorders . This also appears to be the case with dental fear. For example, Humphris and colleagues  found cultural differences in the proportions of patients with high dental anxiety, as well as which dental stimuli were rated as the most feared. This indicates that it would be useful to study dental fear within each culture of interest, rather than extrapolate findings from other cultures.
Greek dentists have noticed fearful behavior in some of their patients but have not had a Greek version of a standard fear questionnaire to accurately assess fear. In addition, researchers have wished to study the effectiveness of fear-reduction techniques in Greek patients, but have likewise been unable to quantify change due to the lack of valid Greek fear measures. Thus, developing and testing Greek dental fear questionnaires would assist dentists and researchers who work with this population. In this paper, we report on the development and psychometric properties of the Greek versions of two dental fear measures for adults, the MDAS , and the DFS .