Dental phobia is part of the Blood-Injection-Injury (B-I-I) phobia subtype of specific phobia within DSM-IV-TR. To investigate the conceptual validity of this classification, the purpose of the present study was to determine the co-occurrence of dental phobia, typical dental (and B-I-I related) fears, vasovagal fainting, and avoidance of dental care.Data were collected by an online survey in Dutch twin families (n = 11,213).Individuals with a positive screen of dental phobia (0.4% of the sample) rated typical B-I-I-related stimuli as relatively little anxiety provoking (e.g. of all 28 fears the stimulus "the sight of blood" was ranked lowest). Presence of dental phobia was significantly associated with a history of dizziness or fainting during dental treatment (OR = 3.4; 95% CI: 1.5-8.1), but of the dental phobic individuals only 13.0% reported a history of dizziness or fainting during dental treatment. Presence of dental phobia (OR = 5.0; 95% CI: 2.8-8.8) was found to be associated with avoidance of dental care, but a history of dizziness or fainting during dental treatment was not (OR = 1.0; 95% CI: 0.8-1.2).The present findings converge to the conclusion that dental phobia should be considered a specific phobia subtype independent of the B-I-I cluster within the DSM classification system.