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>

Study on maternal periodontal diseases of the relationships between porphyromonas gingivalis, serum pro-immflamatory mediators and preterm low birth weight / 华西口腔医学杂志

<p><b>OBJECTIVE</b>To investigate the associations between periodontal diseases, presence of Porphyromonas gingivalis (P. gingivalis), serum levels of pro-inflammatory mediators and preterm low birth weight (PLBW).</p><p><b>METHODS</b>60 women (30 PLBW and 30 healthy women), were recruited after postpartum within 3 days in this case-control study. Periodontal measurements including plaque index (PI), bleeding index (BI), probing pocket depth (PD) and clinical attachment loss (CAL) were assessed. The subgingival plaque was collected before periodontal examination and analysed by polymerase chain reaction (PCR) for the presence of the 16S rRNA gene specific to P. gingivalis, while the venous and umbilical cord blood specimens collected were determined by enzyme-linked immunosorbent assay (ELISA).</p><p><b>RESULTS</b>The PLBW cases had a poorer oral conditions and the presence of P. gingivalis was found in a higher proportion in the PLBW than the healthy pregnant (56.7% vs. 30.0%, P < 0.05). Both of the presence of periodontitis and P. gingivalis have been found to be associated weakly with a shorter gestational age and a lower birth weight (P < 0.05). The levels of IL-1beta, IL-6 and prostaglandin-E2 (PGE2) in both of the blood samples showed higer levels between the PLBW and normal groups (P < 0.01). The IL-1beta and PGE2 levels in maternal serum were higher with a severe periodontal disease in the PLBW group (P < 0.01).</p><p><b>CONCLUSION</b>There may be a possible link between periodontal diseases and PLBW.</p>

A two-year randomized clinical trial of 1.23% fluoride foam on dental caries increment in primary teeth / 中华口腔医学杂志

<p><b>OBJECTIVE</b>To evaluate the effect of bi-annual professional application of 1.23% fluoride foam on caries reduction in the primary dentition over a two-year period.</p><p><b>METHODS</b>In a double-blind, cluster-randomised, placebo-controlled trial, 392 children aged 3 - 4 years from 15 classes were randomly assigned to two groups on a school class basis. The experimental group (8 classes) received a bi-annual fluoride foam application, and the placebo control group (7 classes) received the placebo. The analysis of caries increment was based on the class as the unit of analysis. The independent-samples t tests were performed to compare the differences in caries indices at baseline and caries increments between the two groups.</p><p><b>RESULTS</b>The mean caries increment in foam group was 3.8 dmfs while it was 5.0 dmfs in the placebo control group, resulting in 24.2% caries reduction (P < 0.05). The experimental group had a 37.6% caries reduction on approximal surfaces compared with the placebo control group (P < 0.01). Although the mean dmfs increment of bucco-lingual surfaces was lower in the experimental group than that in the control group, it was not statistically significant (P > 0.05). No significant difference in the mean caries increment was observed on occlusal surfaces between the two groups (P > 0.05).</p><p><b>CONCLUSIONS</b>Bi-annual professional application of fluoride foam was effective in reducing the increment of dental caries in the primary teeth.</p>