A two-week single-group longitudinal test of a new sonic-powered toothbrush simulating the 'bass brushing technique' with tapered bristles on the brush head for reduction of dental plaque and gingivitis.

OBJECTIVE: To investigate the effect of a new powered toothbrush with tapered bristles on the brush head for the reduction of dental plaque and gingivitis. METHODS: This was a single-centre, single-group, longitudinal clinical trial. Thirty-two participants who were typical manual toothbrush users were recruited and assigned the sonic-powered brush. Interviews were arranged on the 1st , 4th , and 15th days which represented the baseline (T1 ), middle (T2 ) and final (T3 ) time points, respectively. At each visit, the plaque index (PlI), gingival index (GI), bleeding on probing (BOP) and probing depth (PD) were recorded for the Ramfjord index teeth, gingival crevicular fluid(GCF) samples were collected and the proportions of eight periodontal pathogenic bacteria were analysed. Repeated-measures analysis of variance (ANOVA) was used for comparisons at different time points. RESULTS: PlI was significantly reduced by 41.67% from T1 to T2 (p<0.001) and decreased by 18.57% from T2 to T3 (p=0.003). GI also varied significantly from T1 to T2 (p=0.018) and T1 to T3 (p=0.037). A 35.86% reduction in the BOP percentage occurred after using the sonic-powered toothbrush for 3 days (p=0.001). However, no significant difference was observed in the mean values of PD at different examination intervals (p=0.529). There was no significant difference in the proportions of bacteria between T1 and T3 (p>0.05). CONCLUSION: This research demonstrated the efficacy of the sonic-powered brush handle together with tapered bristles on the brush in reducing plaque and gingivitis within a short time period.

Analysis of sucrose-induced small RNAs in Streptococcus mutans in the presence of different sucrose concentrations.

Streptococcus mutans (S. mutans) is the major pathogen contributing to dental caries. Sucrose is an important carbohydrate source for S. mutans and is crucial for dental caries. Small RNAs (sRNAs) are key post-transcriptional regulators of stress adaptation and virulence in bacteria. Here, for the first time, we created three replicate RNA libraries exposed to either 1 or 5% sucrose. The expression levels of sRNAs and target genes (gtfB, gtfC, and spaP) related to virulence were assessed. In addition, some phenotypic traits were evaluated. We obtained 2125 sRNA candidates with at least 100 average reads in 1% sucrose or 5% sucrose. Of these candidates, 2 were upregulated and 20 were downregulated in 1% sucrose. Six of these 22 differentially expressed sRNAs were validated by qRT-PCR. The expression level of target gene gtfB was higher in 1% sucrose. The adherence ratio of S. mutans was higher in 1% sucrose than in 5% sucrose. The synthesis of water-insoluble glucans (WIGs) was significantly higher in 5% sucrose than in 1% sucrose. These data suggest that a series of sRNAs can be induced in response to sucrose, and that some sRNAs might be involved in the regulation of phenotypes, providing new insight into the prevention of caries.

The relationship between children's oral health-related behaviors and their caregiver's social support.

BACKGROUND: Social support might play a role in helping people adopt healthy behaviors and improve their health. Stronger social support from mothers has been found to be positively related to higher tooth brushing frequency in 1- to 3-year-old children. However, little is known regarding the relationship between the caregiver's social support and the oral health-related behaviors of 5-year-old children in China. This study aimed to investigate this relationship. METHODS: A cross-sectional study was conducted among 1332 5-year-old children and their caregivers in Guangzhou, southern China. Data were collected using questionnaires that were completed by the caregivers and the children's caries status were examined. The caregivers' social support was measured using the Social Support Rating Scale. The measurements of the children's oral health-related behaviors included the frequencies of sugary snack intake and tooth brushing, utilization of dental services, and patterns of dental visits. Univariate and multiple logistic regression analyses were used to analyze the relationships between the variables. RESULTS: No association was found between the caregiver's social support and the child's oral health-related behaviors in a multiple logistic regression analysis. However, other factors, particularly the oral health-related behaviors of the caregiver, were found to be significantly linked to the child's oral health-related behaviors. CONCLUSIONS: The oral health-related behaviors of 5-year-old children in Guangzhou are unrelated to the caregiver's social support but are related to other specific factors, particularly the caregiver's oral health-related behaviors.

Genetic polymorphisms of the sortase A gene and social-behavioural factors associated with caries in children: a case-control study.

BACKGROUND: Streptococcus mutans (S. mutans) is the primary etiological agent of dental caries. Sortase is a transpeptidase that anchors several surface proteins to the S. mutans cell wall and has been shown to play a major role in cariogenicity. The purpose of this study was to explore the genetic polymorphisms of the sortase gene (srtA) and the social-behavioural factors associated with dental caries in children with S. mutans. METHODS: In this case-control study, 121 S. mutans strains were separately selected from caries-free children and high-severity caries children for sequencing of the srtA gene. Social and behavioural data were collected by self-administered questionnaires. Genomic DNA was extracted from S. mutans strains and amplified by PCR to obtain the srtA gene. The purified PCR products were sequenced and analysed for mutations with ABI Variant Reporter software. The distribution of missense mutations and the mean of social-behavioural factors were compared between the groups. A multiple logistic regression model was used to control for confounding factors. RESULTS: The mutation frequencies at loci 168 (P = 0.023) and 470 (P = 0.032) were significantly different between the groups. The best-fitting model showed that greater age, high frequencies of solid sugar consumption, prolonged breastfeeding, a high proportion of visible plaque, and S. mutans with a T at locus 168 of the srtA gene were associated with high-severity caries in children (P < 0.05). Children carrying a G at locus 168 of S. mutans had a decreased risk for high-severity caries (OR = 0.32, 95% CI = 0.12-0.86) compared with those carrying a T. CONCLUSIONS: The present study suggested that the locus 168 missense mutation of the srtA gene may correlate with caries susceptibility in children with S. mutans. In addition, age, duration of breastfeeding, solid sugar consumption, and poor oral hygiene contributed to this complex disease.

Factors related to children's caries: a structural equation modeling approach.

BACKGROUND: Dental caries among preschool children is highly prevalent in many less-developed countries. METHODS: A model which explored the factors related to children's dental caries was tested in this study using structural equation modeling. Caregivers of children aged 5 years were surveyed on their socioeconomic status, and their oral health knowledge, attitudes and practices. In addition, information on their children's oral health practices, dental insurance and dental service utilization were collected. Examination of caries was conducted on all children who returned fully completed questionnaires. RESULTS: The results showed that socioeconomic factors influenced children's oral health practices through the impact of caregivers' oral health knowledge and practices; that caregivers' oral health knowledge affected children's oral health practices through the influence of caregivers' oral health attitudes and practices; and finally, that children's oral health practices were linked directly to their caries. CONCLUSION: The findings have important applications for promoting policies aimed at advancing children's oral health.

Determining the factors associated with oral health-related quality of life in Chinese elders: Findings from the fourth national survey.

OBJECTIVE: The purpose of this study was to assess the associations between the self-reported oral health-related quality of life (OHRQoL) of older Chinese people and their socio-economic status and oral health using data collected in the 4th National Oral Health Survey. METHODS: After multistage stratified cluster sampling, 4332 adults aged 65-74 years participated in the study. After a clinical examination, the participants completed a structured questionnaire. A Mandarin version of the General Oral Health Assessment Index (GOHAI) was included in the questionnaire. Clinical examinations were carried out using the criteria recommended by the World Health Organization. Multivariate analysis was used to evaluate the associations of the clinical and socio-demographic variables with the GOHAI scores of the participants. RESULTS: The weighted mean (SE) GOHAI score was 51.6 (0.0). Female sex and having more than 10 missing teeth, unrestored tooth spaces, more than 10 decayed teeth and a periodontal pocket ≥6 mm were negatively associated with the GOHAI score, while having a higher education level and living in the Eastern region of China were positively associated with the GOHAI score. CONCLUSION: After adjustment for confounders, the OHRQoL of older Chinese individuals was mainly affected by untreated dental caries and the loss of teeth. Older Chinese individuals who were male, had a higher education level, were from the Eastern region, had no unrestored tooth spaces or deep periodontal pockets and had fewer decayed or missing teeth had higher GOHAI scores, indicating better OHRQoL.

Effect of poly (γ-glutamic acid)/tricalcium phosphate (γ-PGA/TCP) composite for dentin remineralization in vitro.

The poly (γ-glutamic acid)/tricalcium phosphate (γ-PGA/TCP) composite was fabricated as a novel biomineralization material function in preventing caries. Demineralized bovine dentin specimens were prepared and randomly divided into 5 groups (i. α-TCP, ⅱ. γ-PGA, ⅲ. γ-PGA/TCP, ⅳ. CPP-ACP, and ⅴ. deionized water) and subjected to 14 days of pH cycling. Remineralization ability was evaluated by lesion depth, mineral loss and microhardness. The morphology of dentin depositions was observed with scanning electron microscope (SEM), the crystal structure was determined by X-ray diffraction (XRD), and the wettability was tested by contact angle measurements. ANOVA revealed specimens treated by γ-PGA/TCP presented the statistically least lesion depth (p<0.01) and mineral loss (p<0.001), and the highest hardness (p<0.001). SEM revealed prominent intra- and inter-tubular precipitates in both γ-PGA and γ-PGA/TCP groups. The XRD patterns of the deposition structures in all groups were similar to those of sound dentin, and the contact angle of water decreased after γ-PGA/TCP treatment.

Factors Impacting the Oral Health-related Quality of Life in Chinese Adults: Results from the 4th National Oral Health Survey.

OBJECTIVE: To explore the clinical and socio-demographic factors influencing oral health-related quality of life (OHRQoL) of Chinese adults in the 4th National Oral Health Survey. METHODS: Multistage stratified cluster sampling and PPS method were used in sampling and 4720 adults aged 35 to 44 years were recruited. The study subjects completed a structured questionnaire in an interview and underwent a clinical examination. The questionnaire was a Putonghua version of the General Oral Health Assessment Index (GOHAI) and was completed by the interviewer on the site of the 4th National Oral Health Survey. Clinical examination was performed using the criteria recommended by the World Health Organization (WHO). RESULTS: The mean GOHAI score of the subjects was 54.42 (SD 6.01). Result of Poisson regression showed that subjects with a higher household income per capita, had lower DMFT, fewer missing teeth, had no unrepaired missing teeth, or not wearing a partial denture had higher GOHAI scores indicating better OHRQoL. CONCLUSION: The OHRQoL of the adults in China was fair and was mainly influenced by dental caries, integrity of dentition and restoration of lost teeth. With limited resources and dental manpower in China, higher priority should be given to the prevention and treatment of the main cause leading to losing teeth.

The Prevalence and Associated Risk Indicators of Dental Fluorosis in China: Findings from the 4th National Oral Health Survey.

OBJECTIVE: To explore the prevalence and associated risk indicators of dental fluorosis in the mainland of China. METHODS: Data for this study was obtained from the 4th National Oral Health Survey in China, conducted from 2015 to 2016. The sample population was 12-year-old school students. Study participants were selected using a multi-stage, stratified random sample selection procedure using a sampling frame compiled from geographical distribution of China. The level of dental fluorosis was determined using the Dean index recommended by the World Health Organization (WHO). A structured questionnaire was distributed to all the subjects in schools. Participants completed a questionnaire with assistance from staff. A bivariate analysis was performed using the chi-square test. Logistic regression was performed to evaluate the association between dental fluorosis and the independent variables. RESULTS: A total of 27,495 students were evaluated, of which 13,650 (49.6%) were male. Overall, dental fluorosis was found in 13.4% of participants; 6.3% had very mild fluorosis, 4.3% had mild fluorosis, 2.3% had moderate fluorosis, and 0.5% had severe fluorosis. The community fluorosis index was 0.28. In the final logistic regression model students from rural areas (RR:1.582, 95%CI 1.473-1.700), students whose fathers had low education (RR:1.429, 95%CI 1.230-1.661 & 1.184, 95%CI 1.026-1.365), and those students with sibling (RR:1.537, 95%CI 1.414-1.671) were more significantly associated with dental fluorosis. CONCLUSION: As a whole, China has a low dental fluorosis prevalence. Rural areas were the key places for the prevention of dental fluorosis. More prevention measures should be conducted on the children whose fathers were of lower education and who were not an only child.

Randomized clinical trial on the efficacy of electric and manual toothbrushes in plaque removal and gingivitis control in visually impaired school students.

OBJECTIVE: To evaluate the efficacy of electric or manual toothbrushes in plaque removal and gingivitis control in visually impaired adolescents. METHOD AND MATERIALS: A randomized, controlled, examiner-blind crossover design was used in the study. Study subjects were 12- to 16-year-old visually impaired students from the School for the Blind in Guangzhou. Students in the test group used electric toothbrushes, whereas those in the control group used manual toothbrushes. The study consisted of two stages. Oral health status of the students was recorded at baseline, 2 weeks, and 4 weeks of each stage. In total, 42 visually impaired students were recruited in the study at baseline during the first stage. Quigley-Hein Plaque Index (Q-H PI) and Loe and Silness Gingival Index (GI) were used. One-way repeated measures analysis of variance followed by post hoc analysis was used to compare the mean Q-H PI and GI scores obtained at baseline, 2-week, and 4-week examinations between the test and control groups. RESULTS: In total, 33 subjects completed the study. No significant differences were noted between the two groups regarding Q-H PI and GI at baseline, whereas Q-H PI and GI values of the test group were significant reduced compared with those of the control group at 2 weeks and 4 weeks (P < .001). CONCLUSION: An electric toothbrush reduced plaque and gingivitis more than manual toothbrushing among visually impaired school children.

Prevalence of non-carious cervical lesions and associated risk indicators in middle-aged and elderly populations in Southern China.

OBJECTIVE: To explore the prevalence of NCCL and associated risk indicators in 35- to 44-year-olds and 65- to 74-year-olds from both urban and suburban districts of Guangzhou, Southern China. METHODS: A cross-sectional survey was conducted on NCCL with a sample of 768 35- to 44-year-olds and 991 65- to 74-year-olds, and the Tooth wear index was applied to record the tooth wear. Data on socioeconomic status, health behaviour and general health condition were obtained from a structured questionnaire. RESULTS: The prevalence of NCCL was 76.8% and 81.3% in middle-aged and elderly populations, respectively. The results from the analysis of covariance (ANCOVA) demonstrated that for the 35- to 44-year-olds, those who were male, older, living in the suburban district and used toothpicks frequently, they tended to have more teeth with NCCL. Men, who were aged between 65 and 74 years old, who used toothpicks frequently, drank vinegar beverages, ate hard food and had not visited a dentist in a year; tended to have more teeth with NCCL. CONCLUSION: NCCL was very common amongst middle-aged and elderly populations in South China. Older men who had unhealthy oral habits like using toothpicks, eating hard food and drinking vinegar beverages tended to have more teeth with NCCL. Oral health education would benefit those at risk.

Randomized clinical trial on effectiveness of silver diamine fluoride and glass ionomer in arresting dentine caries in preschool children.

OBJECTIVE: To compare the effectiveness of annual topical application of silver diamine fluoride (SDF) solution, semi-annual topical application of SDF solution, and annual application of a flowable high fluoride-releasing glass ionomer in arresting active dentine caries in primary teeth. METHODS: A total of 212 children, aged 3-4 years, were randomly allocated to one of three groups for treatment of carious dentine cavities in their primary teeth: Gp1-annual application of SDF, Gp2-semi-annual application of SDF, and Gp3-annual application of glass ionomer. Follow-up examinations were carried out every six months to assess whether the treated caries lesions had become arrested. RESULTS: After 24 months, 181 (85%) children remained in the study. The caries arrest rates were 79%, 91% and 82% for Gp1, Gp2 and Gp3, respectively (p=0.007). In the logistic regression model using GEE to adjust for clustering effect, higher caries arrest rates were found in lesions treated in Gp2 (OR=2.98, p=0.007), those in anterior teeth (OR=5.55, p<0.001), and those in buccal/lingual smooth surfaces (OR=15.6, p=0.004). CONCLUSION: Annual application of either SDF solution or high fluoride-releasing glass ionomer can arrest active dentine caries. Increasing the frequency of application to every 6 months can increase the caries arrest rate of SDF application. CLINICAL SIGNIFICANCE: Arrest of active dentine caries in primary teeth by topical application of SDF solution can be enhanced by increasing the frequency of application from annually to every 6 months, whereas annual paint-on of a flowable glass ionomer can also arrest active dentine caries and may provide a more aesthetic outcome.

[Arbitrarily primed-PCR detection of Streptococcus mutans and Streptococcus sobrinus in dental plaque of children with high dmft and no caries].

OBJECTIVE: To isolate and identify Streptococcus mutans (Sm) and Streptococcus sobrinus (Ss) in dental plaque of children with high dmft and no caries by selective medium, biochemical methods and arbitrarily primed-polymerase chain reaction (AP-PCR). METHODS: A total of 401 3-4-year-old children from seven kindergartens were recruited using cluster sampling and their dental caries status were examined. From 30% of children with the highest dmft score (dmft >/= 5), 20 children were chosen randomly as test group and 20 age and gender-matched caries-free children were selected as control. Plaque samples were collected from buccal surfaces of the molars and plated onto TYCSB plate. Sm and Ss were primarily identified by colony morphology and biochemical characteristics. Then chromosomal DNA of the strains was isolated and Sm or Ss were confirmed by AP-PCR. RESULTS: The proportion positive for Sm and Ss in children with high dmft was 100% and 40% respectively while that in caries-free children was 75% and 5% by AP-PCR analysis. The differences were statistically significant between the two groups. CONCLUSIONS: The proportions positive for Sm and Ss detected by AP-PCR method were significantly higher in children with high dmft than in caries-free children and it is a risk factor for high dmft in deciduous teeth harboring Sm and Ss.

[A study on oral health behavior and other related factors between children with high dmft and no caries].

OBJECTIVE: To explore the risk factors of children with high dmft. METHODS: In suburban of Guangzhou, oral health of 401 3 - 4-year-old children were examined and structured questionnaire were completed by their parents. 120 children with highest number of dmft (dmft > or = 5) and 118 caries-free children were chosen for case-control analysis. RESULTS: The results of logistic regression analysis showed that the factors associated with high dmft were developmental defect of enamel, visible plaque index, frequency of toothbrushing, frequency of sugar consumption, and income. CONCLUSIONS: Advocating brushing teeth at least twice daily, controlling the frequency of sugar consuming, reducing the developmental defect of enamel and paying more attention to the oral health of lower income population may effectively reduce dental caries of the children.