The prevalence, distribution, and possible causal factors of cervical dentin hypersensitivity were studied in a population attending the Health Examination Center of National Taiwan University Hospital. A total of 780 patients were examined for the presence of cervical dentin hypersensitivity by means of a questionnaire and intraoral tests. There were 253 patients (32%) who claimed to have hypersensitive teeth at present and 90 patients (12%) who reported a history of hypersensitive teeth. The intraoral distribution of hypersensitivity showed that premolars and molars were the most common teeth sensitive to the air and probe stimuli, while the incisors were the least sensitive ones. The presence and history of dentin hypersensitivity were positively correlated with previous tooth-brushing and periodontal disease. Only a few of the patients who claimed to have dentin hypersensitivity had tried treatment with desensitizing tooth-pastes (11%) or sought professional help (5%).