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Heritability of Dental Fear

The objective was to test a hypothesized genetic component (i.e., monozygotic being more similar compared with dizygotic twins) in dental fear/anxiety by comparing the probandwise concordance. We analyzed data based on a dichotomous measure of Dental Fear/Anxiety and a continuous measure of Dental Fear Intensity from over 2000 twins, collected when participants were 13–14 years old and once again three years later. The hypothesis was confirmed, but heritability of Dental Fear/Anxiety was estimated to be higher for girls (0.77 at time 1 and 0.55 at time 2) than for boys (0.14 and 0.0 at times 1 and 2, respectively). Heritability of Dental Fear Intensity, however, was similar for girls (0.30 and 0.40 at times 1 and 2, respectively) and boys (0.47, 0.44). Studies of the etiology of dental fear/anxiety should take genetic vulnerability into account and include molecular biology measures. Possible heritability differences between girls and boys need attention.