A national survey on dentin hypersensitivity in Chinese urban adults / 中华口腔医学杂志

<p><b>OBJECTIVE</b>To investigate the prevalence of dentin hypersensitivity in Chinese urban adults aged between 20 - 69 years old and the factors related to dentin hypersensitivity.</p><p><b>METHODS</b>The Chinese national survey on dentin hypersensitivity was conducted in 20 - 69 years old adults in six representative cities, Beijing, Shanghai, Guangzhou, Wuhan, Chengdu, and Xi'an in 2008. A multi-stage stratified randomizing sampling method was used. Subjects were recruited from 36 urban survey sites in 6 cities. A structured questionnaire and a clinical examination on dentin hypersensitivity were used in the survey. The dentin hypersensitivity was diagnosed by a subject self-perceived short, sharp pain in response to a blast of cold air from a triple syringe administered to a tooth surface in 1 cm.</p><p><b>RESULTS</b>In total, 7939 twenty to sixty-nine years old subjects completed a structured interview and underwent a clinical examination on dentin hypersensitivity. Among them, 40.7% (3230/7939) of the subjects reported being suffered from teeth sensitivity. When confirmed using a blast of air from a triple syringe and by ruling out other causes of sensitivity, such as caries, the prevalence was 29.7% (2354/7939), and the mean number of sensitive teeth was 1.4. The highest prevalence of dentin hypersensitivity [39.1% (622/1592)] was found in 50 - 59 years old group. The commonest teeth affected were the premolar teeth and the commonest initiating factor was cold drinks. Female, low education level, with gingival recession, attachment loss, and with the history of acidic substances derived from the stomach was related to dentin hypersensitivity.</p><p><b>CONCLUSIONS</b>Dentin hypersensitivity was common in 20 - 69 years old Chinese urban adults. Dental professionals should give further emphasis to it.</p>

Effect of drinking water change upon the dental fluorosis / 中华口腔医学杂志

<p><b>OBJECTIVE</b>To assess changes in prevalence and degree of dental fluorosis in individuals born before and after the introduction of water with 1.2 mg/L fluoride instead of water with 2.0-10.0 mg/L fluoride previously used in Da Li County in China.</p><p><b>METHODS</b>The students (n = 291) were divided into 2 groups. The dental fluorosis was scored according to Dean's classification. The statistical analysis was performed by t-test and chi(2) tests.</p><p><b>RESULTS</b>The prevalence of dental fluorosis was significantly lower in the group of the students drinking water from the new well (group 1) as compared to the group of the students drinking the old water (group 2), i.e. 48.8% versus 87.2% (P < 0.01). The percentage of moderate to very severe fluorosis was 13.9% and 0 in group 1 as compared to 32.0% and 8.8% in group 2. The fluorosis community index (FCI), defined by Dean, in group 1 and 2 was medium (1.01) and marked (2.12) respectively.</p><p><b>CONCLUSIONS</b>The results showed that: (1) The prevalence of dental fluorosis was significantly lowered by the new source of drinking water. (2) Drinking water, even with 1.2 mg/L fluoride, may cause dental fluorosis during the period of tooth mineralization.</p>