Stress and dental caries in the rat

The stress of crowding and exposure to inescapable electric shock increased both the incidence and the severity of dental caries in rats housed in a conventional animal facility. Male Osborne-Mendel rats were inoculated intraorally with cariogenic bacteria, fed a high-sucrose diet, and housed in either a conventional or a sheltered facility. Rats in both housing conditions were subdivided into control and stress groups. At the end of the 56-day trial period, stressed rats from conventional housing had a significant increase in both incidence and severity of dental caries in comparison to their controls. In contrast, stressed rats from sheltered housing had a trend toward increased cariogenesis which reached significance in only one of five scores. These rats also failed to gain weight comparable to their controls, making it possible that stress-induced reduction in appetite partially offset stress-induced exacerbation in cariogenesis.This investigation was supported in part by the following Grants from the United States Public Health Service: CA 20093, HL 22727, and HL 07374.     

Potential impact of hormonal male contraception: cross-cultural implications for development of novel preparations

The prospect of a hormonal male contraceptive is no longer distant. Data on the potential impact of this improvement in contraceptive provision, however, is limited, particularly between different cultures. We have therefore carried out a multi-centre study to assess men's attitudes to proposed novel hormonal methods. Questionnaire-based structured interviews were administered to men in Edinburgh, Cape Town, Shanghai and Hong Kong. Approximately 450 men were interviewed in Edinburgh, Shanghai and Hong Kong, and a slightly larger group (n = 493) in Cape Town to give samples (n > 150) of black, coloured and white men. Knowledge of existing male and female methods of contraception was high in all centres and groups. The majority of men welcomed a new hormonal method of contraception, 44-83% stating that they would use a male contraceptive pill. Overall, a pill was more acceptable than an injectable form (most popularly given at 3-6 month intervals); long-acting implants were least so except in Shanghai. Familiarity with comparable female methods appeared to influence acceptability, for both oral and injectable methods. Hong Kong was the only centre where a male method (condom) was currently the most commonly used; men there appeared to rate the convenience of condoms highly while being least likely to think that they provided effective protection against pregnancy compared to other centres, and were least enthusiastic about novel male methods. The acceptability of potential male hormonal methods of contraception was high in some groups but showed wide variability, determining factors including cultural background and current contraceptive usage. These results suggest that the emerging emphasis that men should have greater involvement in family planning will be substantiated when appropriate contraceptive methods become available.     

Mirror-image dental fusion and discordance in monozygotic twins

A pair of monozygotic twins had similar but not identical dental anomalies. One twin had fusion of deciduous mandibular lateral incisor and canine on the left, with normal dentition on the right; the co-twin had right mandibular incisor/canine fusion, with aplasia of the lateral incisor on the left. These findings are discussed in the context of the related phenomena of situs inversus, mirror-imaging in twins, and gradients of severity of anomalies in the four copies of the mandibular developmental dental field. © 1994 Wiley-Liss, Inc.     

Characteristics of employment and job satisfaction in nontraditional dental hygiene practice settings

Little is known concerning the employment characteristics of hygienists practicing in nontraditional settings. Respondents were identified through screening (n = 38,380) a listing of the entire population of hygienists licensed in the United States. The screening identified 1,301 hygienists practicing in nontraditional settings. These hygienists were mailed comprehensive questionnaires; completed questionnaires were returned by 84.3 percent of the hygienists. Data were collected describing hygienists' reasons for seeking employment in nontraditional settings, their sources of information concerning job opportunities in nontraditional settings, benefits, and job satisfaction. The main source of information concerning employment opportunities in nontraditional settings was "word of mouth." Hygienists were motivated to seek employment in nontraditional settings primarily by a desire for a more challenging position and personal satisfaction. The hygienists were overwhelmingly satisfied with all aspects of nontraditional employment except opportunities for advancement. Respondents were found to receive standard benefits similar to those of employees in other industries.     

Characterization and cross-reactivity of rabbit antisera to plaque toxins

The effects of heat labile, high molecular weight water-soluble toxins from bacterial plaque on HL60 promyelocytic cells were examined. On gel filtration, four inhibitors of HL60 cell growth and two inhibitors of HeLa cell growth (PT1, PT2) were detected. The first and third HL60 cell inhibitors corresponded to the two HeLa cell inhibitors. The last eluted HL60 cell inhibitor (plaque leukotoxin, PL) did not inhibit HeLa cell growth. Anti-PT2 antibodies reduced the activity of enriched PT2 by 20-50%, but all other antisera tested exhibited no effect. Anti-PL antibodies detected antigens from Actinobacillus actinomycetemcomitans, although anti-A. actinomycetemcomitans and anti-Capnocytophaga sputigena antibodies did not react with plaque extract. These findings suggest that the plaque toxins examined in this study were probably not derived from these two bacteria.     

Prevalence and distribution of gingivitis and dental caries in children aged 6–12 years in Brisbane primary schools

A study of caries experience and gingivitis prevalence in 6-, 9- and 12-yr-old children attending primary schools in Brisbane was undertaken in November/December 1983. Children from high socioeconomic level (SEL) schools exhibited lower dmft and DMFT scores at all ages. At age 6 yr the proportion of children with caries-free primary dentitions was for high SEL Schools 70%, for middle SEL schools 52% and for low SEL Schools 23%. At 12 yr DMFT scores were 1.8 (high), 2.1 (middle) and 3.3 (low). Similar differences in gingivitis prevalence occurred, children from high SEL schools displaying a much lower proportion of bleeding sites than those from middle and low SEL schools. For selection of children at "high risk" to gingival disease for intensive prevention programmes, an increased emphasis on probing techniques is indicated to achieve diagnostic consistency.     

Free Sugars Intake among Chinese Adolescents and Its Association with Dental Caries: A Cross-Sectional Study

This study aims to estimate the free sugars intake, identify the primary food sources of free sugars, and explore the relationship between free sugars intake and dental caries among Chinese adolescents. This cross-sectional study included 1517 middle-school students aged 12–14 years in Changsha city, China. Adolescents completed a 12-item Food Frequency Questionnaire (FFQ) and oral health assessment. The students’ dental caries experience was available as DMFT score (number of decayed, missing, and filled permanent teeth). Statistical analyses included the Mann–Whitney test, Kruskal–Wallis test, Chi-square test, and binary logistic regression model. The average intake of free sugars was 53.1 g/d in adolescents, and 43.2% of the students consumed more than 50 g of free sugars daily. The primary contributor to free sugars was sugar-sweetened beverages (SSBs). Age, boarders, and high family income were risk factors for excessive free sugars intake (p < 0.05), and increased free sugars intake was a risk factor for dental caries (odds ratio, OR = 1.446, 95% confidence interval: 1.138–1.839). Both the free sugars intake and dental caries prevalence in Chinese adolescents were high. Targeted interventions are urgently needed to address the excessive consumption of free sugars and improve Chinese adolescents’ oral health.     

Ten years of Pan-InfORM: modelling research for public health in Canada

Modelling and simulation methods can play an important role in guiding public health responses to infectious diseases and emerging health threats by projecting the plausible outcomes of decisions and interventions. The 2003 SARS epidemic marked a new chapter in disease modelling in Canada as it triggered a national discussion on the utility and uptake of modelling research in local and pandemic outbreaks. However, integration and application of model-based outcomes in public health requires knowledge translation and contextualization. We reviewed the history and performance of Pan-InfORM (Pandemic Influenza Outbreak Research Modelling), which created a national infrastructure in Canada with a mandate to develop innovative knowledge translation methodologies to inform policy makers through modelling frameworks that bridge the gaps between theory, policy, and practice. This review demonstrates the importance of a collaborative infrastructure as a “Community of Practice” to guide public health responses, especially in the context of emerging diseases with substantial uncertainty, such as the COVID-19 pandemic. Dedicated resources to modelling and knowledge translation activities can help create synergistic strategies at the global scale and optimize public health responses to protect at-risk populations and quell socioeconomic and health burden.     

Loops and Building Blocks: a Knowledge co-Production Framework for Equitable Urban Health

This paper sets out a structured process for the co-production of knowledge between researchers and societal partners and illustrates its application in an urban health equity project in Accra, Ghana. The main insight of this approach is that research and knowledge co-production is always partial, both in the sense of being incomplete, as well as being circumscribed by the interests of participating researchers and societal partners. A second insight is that project-bound societal engagement takes place in a broader context of public and policy debate. The approach to co-production described here is formed of three recursive processes: co-designing, co-analysing, and co-creating knowledge. These ‘co-production loops’ are themselves iterative, each representing a stage of knowledge production. Each loop is operationalized through a series of research and engagement practices, which we call building blocks. Building blocks are activities and interaction-based methods aimed at bringing together a range of participants involved in joint knowledge production. In practice, recursive iterations within loops may be limited due of constraints on time, resources, or attention. We suggest that co-production loops and building blocks are deployed flexibly.