Dental anxiety is the type of anxiety experienced by the patients who are soon to visit a dentist for an appointment or treatment (Bracha, Vega & Vega 2006; Saatchi et al. 2015). Oral health procedures are perceived as frightening (Appukuttan et al. 2013; Saatchi et al. 2015). Due to the negative expectations, the patients with high levels of dental anxiety may behave in an aggravated manner and disrupt the professional’s work (Frydendal Hoem & Marlén Elde 2012). That way, dental anxiety is a significant issue for both the dentists and their patients. The prevalence of dental anxiety was evaluated in many studies conducted throughout the world. This review presents the definition, risk factors of dental anxiety, its epidemiology, four groups of patients, impact, techniques of addressing dental anxiety, its effects, and assessment methods. Definition To provide an appropriate definition of dental anxiety, it is important to define fear at first. Fear is characterized as an individual’s reaction to a dangerous event or a threatening environment (Naudi 2009). In this regard, dental anxiety can be described as an individual’s perception of versatile dental procedures and visits to the dentist overall as threatening and dangerous (Naudi 2009). Settineri et al. (2013) argued that dental anxiety should be classified as a part of the family of mood disorders instead of that of anxiety disorders. That way, studying the facts that contribute to the prevalence of anxiety in dental patients, the researchers should study the psychopathological profiles of anxious individuals (Settineri et al. 2013). This conclusion implies the need for cross-disciplinary links between dentistry and psychiatry. In fact, from the psychological perspective, dental phobia, as a term, maybe a misnomer; Bracha, Vega, and Vega (2006) propose a new name for it – Posttraumatic Dental Care Anxiety- a term that reflects the nature and the most common cause of the phenomenon. According to this study, the prevalence of dental anxiety is likely to be 14 times higher in the patients who had experienced painful dental treatments who also become 16 times less compliant with dental care and just as unwilling to return to the dentist’s office for another procedure. Due to the feeling of anxiety and fear, the patients may demonstrate inadequate behaviors during their dental treatments (Madfa et al. 2015). Also, many patients tend to avoid visiting a dentist for their regular checkups and dental procedures when they experience dental health problems (Gaffar, Alagl & Al-Ansari 2014). Epidemiology Dental anxiety is a phenomenon that was registered all around the world. Many studies have been done to evaluate the prevalence of dental anxiety. Fear of dentists is one of the most common phobias registered by the psychologists (Yip 2012). Moreover, the overall prevalence of dental anxiety may vary from one group of patients to another and also is diverse in different countries. (Naudi 2009). Depending on the types of subjects and their characteristics, the researcher all around the globe reported rates of dental anxiety that hesitate from very low to very high (Naudi 2009). In other words, it is possible to conclude that geography is an insignificant factor when it comes to the prevalence of dental anxiety (Nau