Morphological and numerical characteristics of the southern Chinese dentitions. Part II: traits in the permanent dentition

Aim: To investigate the prevalence of four major dental traits in the southern Chinese permanent dentition and to compare these with studies from different populations. Materials and Methods: The material used in the study consisted of high quality study models collected from 725 randomly selected 12-year-old children in Hong Kong (358 males and 367 females). The various traits were assessed using standard diagnostic criteria. Literature and data related to dental traits in the permanent dentition were sourced using PubMed and hand searches. Results: The mouth prevalence of shovelling, lingual tubercle, Carabelli’s trait, and protostylid were 80.4%, 38.9%, 50.5% and 37.5% respectively. The prevalence figure for the cusp type of Carabelli’s trait in this study (23.7%) was higher than for other Mongoloids. The prevalence figures for semi-shovel shaped maxillary incisors (42.6% to 48.6%) and the cusp type of protostylid trait in mandibular molars (10.1%) were higher than for any other populations. Conclusion: The higher prevalences of semi-shovel shaped maxillary incisors, and protostylid cusp on the mandibular molars can be considered to be characteristics of the southern Chinese permanent dentition.published_or_final_versio

Morphological and numerical characteristics of the southern Chinese dentitions. Part I: anomalies in the permanent dentition

Aim: To investigate the prevalence of eight morphological and numerical anomalies in the southern Chinese permanent dentition and to compare these with studies from different populations. Materials and Methods: The material used in the study consisted of study models and panoramic radiographs collected from 725 randomly selected 12-year-old children (358 males and 367 females). The anomalies were assessed using diagnostic criteria that have been most often cited in the published literature. Results: Of the eight dental anomalies studied, the prevalence of hyperdontia (2.6%) was higher than reported for Caucasians, and double tooth (0.8%) and dens evaginatus (4.7%) were the highest amongst all of the populations. Although the prevalence of hypodontia (7.3%) is comparable to that of other populations, mandibular incisors were the most frequently missing teeth in southern Chinese (5.6%) and this finding contradicted those from studies of other ethnic groups. Conclusion: Higher prevalences of double tooth, dens evaginatus and missing mandibular incisors can be considered to be characteristics of the southern Chinese permanent dentition.published_or_final_versio

Feeding and oral hygiene habits of preschool children in Hong Kong and their caregivers' dental knowledge and attitudes

Objectives. This study was designed to gather data on infant feeding habits and oral hygiene practices of Hong Kong preschool children, on the dental knowledge and attitudes of their caregivers and on the oral health status of the same group of children. Design. Cross-sectional study. Sample and methods. Data was gathered for a total of 369 boys and 297 girls (207 1-year-olds, 269 2-year-olds and 190 3-year-olds) with a mean age of 20-19 (± 0.38) months. Information related to children attending six randomly selected Maternity and Child Health Centres. It was obtained by examining the children and by interviewing the attending caregivers and completing a questionnaire. Each child was given an oral examination using a torch, disposable mirror and wooden tongue spatula. Results. Only 7% of the children were exclusively breast-fed. More than 98% (656/666) of infants used a nursing bottle for at least some drinks. Over 62% (411/656) had used a nursing bottle to take fluids other than water and infant formula. At bedtime, 56% (361/656) were given a nursing bottle prior to sleep and 96% (340/361) of these bottles contained formula milk. Of these children, only 37% (131/361) finished the contents of the bottle before falling asleep. Over 73% (139/190) of the children continued to use a feeding bottle after 2 years of age. Non-nutritive sucking habits were practised by 35.6% (237/666) of the children. Visible plaque, on the labial surface of at least two maxillary incisors, was found in 19.5% (120/615) of the children. Oral cleansing habits were practised for 66.2% (441/666) of the children. Toothbrushing habits were reported for 42.3% (260/615) of the dentate children, of whom 19% (49/260) had their teeth brushed twice daily. Toothpaste was used by 49.23% (128/260) of the children and 57.3% (149/260) brushed their own teeth. Caries was seen in 7.6% of the infants (47/615). Of the caregivers, 67.7% said they did not think carious primary teeth needed to be restored. Among the mothers, 12.6% (43/342) did not know the oral condition of their child. Reportedly, 82% (417/510) and 87.5% (446/510) of the mothers had not received any oral health care information during the ante- or postnatal periods. Nearly all, 97%, of the respondents said that they would like to receive more information on oral health care.postprin

Bonding of some self-etch adhesives to unground enamel

Abstract no. 0027published_or_final_versio

Caries prevalence and distribution, and oral health habits of zero- to four-year-old children in Macau, China

This study sought to determine the prevalence of early childhood caries and the oral health habits of children ages 0 to 4 years in Macau, China vs. children in Hong Kong. Caregivers of 353 children from 7 nursery centers completed a questionnaire, and dental personnel examined their children with a light and disposable mouth mirror. The children's mean age was 2.8±0.6 years. Using the diagnostic criterion that cavitation was evidence of dental caries, the caries prevalence was 18%. When the age range was narrowed to 1.8 to 3.5 years, the caries prevalence was 19% in Macau children compared to 17% in Hong Kong children. No statistically significant relationship existed among caries prevalence, feeding habits, or oral hygiene habits, supporting the notion that the etiology of ECC is multifactorial. The similarity of caries prevalence in these 2 populations may result from the effects of cultural norms on the dental habits of the children.link_to_subscribed_fulltex

The dental knowledge and attitudes of medical practitioners and caregivers of pre-school children in Macau

The dental knowledge and attitudes of medical practitioners and caregivers of pre-school children in Macau were investigated. The caregivers of 353 children (2.8 ± 0.6 years) from seven nursery centers completed a questionnaire and their children's had their teeth examined. Thirty medical practitioners completed the same questionnaire prior to a dental health seminar. The dental knowledge and attitudes of the medical practitioners were found to be better than those of the caregivers. Topics, such as, "acid can cause caries"; "fluoridated water can prevent caries" and "primary teeth play a role in the development of the permanent teeth" were significantly associated with caries in the caregivers' children (p<0.05). It is hypothesised that the medical practitioners had not conveyed their dental knowledge to the caregivers early enough so as to prevent the occurrence of caries in their children.link_to_subscribed_fulltex