Positive impacts of oral health services provision by a student-led primary care clinic to an Australian rural indigenous community

BACKGROUND

This study aimed to determine whether oral health services provision by a dental student clinical outplacement embedded within a Community Controlled Health Service positively impacted a rural Indigenous community and to explore the nature of these benefits.

METHODS

Aggregated and de-identified 2017, 2018 and 2019 student-led clinic services provision data were retrospectively analysed. The change in services mix over time was measured. Rural outplacement clinic operational costs to the university were estimated. Government-funded local public dental clinic waiting list and services provision data were used to identify any student clinic establishment effect.

RESULTS

The student-led clinic services mix shifted over time from mainly acute care for toothache towards prevention of disease and tooth restoration, indicating an improvement in patient oral health and correspondingly reduced system costs. Imputed value of 2017-2019 student-led clinic services provision totalled almost AUD$1 million. Government public clinic waiting list times decreased after full establishment of the student-led clinic, indicating decreased pressure on the public system.

CONCLUSION

The Community Controlled Health Service and university partnership improved community oral health care access, its timely delivery and simultaneously provided valuable human capital development from the student training experience. The student-led clinic's targeted Indigenous community showed oral health improvement over time. © 2023 Australian Dental Association.

Gender diversity of the oral health leadership in Australia

BACKGROUND

Gender diversity in oral health leadership is important. Globally, this is dominated by men and does not equitably represent the increasing women in the workforce.

METHODS

Publicly available and gathered data on leadership positions for Australian professional associations, accrediting body, specialist academies, training institutions and the public dental sector were analysed for gender (men and women) diversity.

RESULTS

The gender diversity of the leadership varies across the oral health organizations and training institutions. Of the 383 identified leadership positions, 229 (60%) are held by men. Of the eight national dentist association presidents, six (75%) are men. Of the 65 leadership positions across 13 training institutions, 39 (59%) are held by men, and all schools training dentists are led by men. Men also dominate leadership roles in the specialist academies (62%), the research organizations (56%) and public dental sector (67%). Women do have the majority of senior leadership roles in the accrediting body (67%).

CONCLUSION

Gender diversity of the oral health leadership shows some positive findings, but there is still an effort required to increase women leaders across many areas of this leadership. This should urgently be recognized as a problem, with the implementation of strategies to address this important issue. © 2023 Australian Dental Association.

Workforce Planning Models for Oral Health Care: A Scoping Review

BACKGROUND

For health care services to address the health care needs of populations and respond to changes in needs over time, workforces must be planned. This requires quantitative models to estimate future workforce requirements that take account of population size, oral health needs, evidence-based approaches to addressing needs, and methods of service provision that maximize productivity. The aim of this scoping review was to assess whether and how these 4 elements contribute to existing models of oral health workforce planning.

METHODS

A scoping review was conducted. MEDLINE, Embase, HMIC, and EconLit were searched, all via OVID. Additionally, gray literature databases were searched and key bodies and policy makers contacted. Workforce planning models were included if they projected workforce numbers and were specific to oral health. No limits were placed on country. A single reviewer completed initial screening of abstracts; 2 independent reviewers completed secondary screening and data extraction. A narrative synthesis was conducted.

RESULTS

A total of 4,009 records were screened, resulting in 42 included articles detailing 47 models. The workforce planning models varied significantly in their use of data on oral health needs, evidence-based services, and provider productivity, with most models relying on observed levels of service utilization and demand.

CONCLUSIONS

This review has identified quantitative workforce planning models that aim to estimate future workforce requirements. Approaches to planning the oral health workforce are not always based on deriving workforce requirements from population oral health needs. In many cases, requirements are not linked to population needs, while in models where needs are included, they are constrained by the existence and availability of the required data. It is critical that information systems be developed to effectively capture data necessary to plan future oral health care workforces in ways that relate directly to the needs of the populations being served.

KNOWLEDGE TRANSFER STATEMENT

Policy makers can use the results of this study when making decisions about the planning of oral health care workforces and about the data to routinely collect within health services. Collection of suitable data will allow for the continual improvement of workforce planning, leading to a responsive health service and likely future cost savings.

A state-wide study of dental comorbidities in psychiatric disorders resulting in avoidable emergency department presentations

BACKGROUND

Attendances at emergency departments (EDs) for dental conditions are unnecessary and come at a significant cost to health services.

METHODS

A population-based record-linkage analysis of a retrospective cohort over 2 years across state-based facilities in Queensland. This was to determine if people with mental illness were more likely than the general population to attend EDs for a range of non-traumatic or avoidable dental conditions.

RESULTS

There were 1 381 428 individuals in the linked database, of whom 177 157 (13%) had a psychiatric history and 22 046 (1.5%) had one or more avoidable dental presentations. These were toothache (n = 9619), dental abscesses (n = 8449), caries (n = 1826), stomatitis (n = 1213) and gum disease (n = 939). After adjusting for confounders, psychiatric patients were significantly more likely to present with toothache, dental abscesses and caries but not stomatitis or gum disease. Depending on the dental outcome, other risk factors were male sex, lower income, rurality and Indigenous status.

CONCLUSIONS

Given these findings, possible interventions should include an increased emphasis on assessing oral health in mental health or primary care, especially in non-metropolitan areas, as well as early dental referral. Service planning for this population should including easier navigation of dental services, availability outside normal office hours and free outreach dental clinics.

An exploratory study of perfectionism, professional factors and psychological well-being of dentistry academics

BACKGROUND

Well-being might be lower among dentistry professionals than other health professionals, and differ by personal, professional and sociodemographic factors. Few studies have considered dentistry academics who have different work roles and functions than clinicians. This exploratory study focused on well-being among dentistry academics and aimed to explore associations with perfectionism, professional factors and sociodemographics.

METHOD

An online survey was carried out with academic staff in Dentistry and Oral Health departments of nine Universities in Australia and New Zealand. Well-being was assessed using the 22-item Psychological General Well-Being Index, with a maximum score of 110 indicating good well-being. Perfectionism was assessed using the 8-item Short Almost Perfect Scale, with a maximum score of 56 and a higher score indicating perfectionism. Twenty items were used to assess professional and 7 items assessed sociodemographic factors. Associations were explored using correlation and multiple linear regression.

RESULTS

There was no significant bivariate association between perfectionism and well-being. Multiple linear regression indicated a significant association between hours of undergraduate teaching and psychological well-being, after adjustment for age, gender, income and overall health.

CONCLUSION

This exploratory study showed poor well-being among dentistry academics, particularly in those teaching undergraduate students for more than 6 h/week.

A Causative Approach to Demographic and Socioeconomic Factors Affecting Parental Ratings of Child Oral Health

INTRODUCTION

Many studies have investigated associations between demographic, socioeconomic status (SES), behavioral, and clinical factors and parental ratings of child oral health. Caries experience, pain, missing teeth, malocclusions, and conditions and treatments likely to negatively affect the child or family in the future have been consistently associated with poorer parental ratings. In contrast, effect sizes for associations between demographic and SES indicators (race/ethnicity, country of birth, family structure, household income, employment status, and parental education levels) and parental ratings vary greatly.

OBJECTIVES

The primary objectives of this study were to estimate effect sizes for associations between demographic and SES variables and parental ratings of child oral health and then to consider possible causal implications.

METHODS

This article uses a nationally representative data set from 24,664 Australian children aged 5 to 14 y, regression analyses guided by a directed acyclic graph causal model, and sensitivity analyses to investigate effects of demographic and SES factors on parental ratings of oral health.

RESULTS

One in 8 children had oral health rated as fair or poor by a parent. Indigenous children, older boys, young children with a migrant parent, children from single-parent families, low-income households and families where no parent worked full-time, and children whose parents had lower education levels were much more likely to receive a fair or poor parental oral health rating in crude and adjusted models.

CONCLUSION

This cross-sectional study helps to clarify inconsistent findings from previous research and shows many demographic and SES variables to be strong determinants of parental ratings of child oral health, consistent with the effects of these variables on other health outcomes. Sensitivity analyses and consideration of the potential for chance and bias to have affected these findings suggest that many of these associations may be causal.

KNOWLEDGE TRANSFER STATEMENT

Based on regression analyses driven by a directed acyclic graph causal model, this research shows a strong impact of demographic and socioeconomic determinants on parental ratings of child oral health, consistent with associations between these variables and other oral and general health outcomes. Many of these associations may be causal. We demonstrate the value of causal models and causal thinking when analyzing complex multilevel observational data.

Global, Regional, and National Levels and Trends in Burden of Oral Conditions from 1990 to 2017: A Systematic Analysis for the Global Burden of Disease 2017 Study

Government and nongovernmental organizations need national and global estimates on the descriptive epidemiology of common oral conditions for policy planning and evaluation. The aim of this component of the Global Burden of Disease study was to produce estimates on prevalence, incidence, and years lived with disability for oral conditions from 1990 to 2017 by sex, age, and countries. In addition, this study reports the global socioeconomic pattern in burden of oral conditions by the standard World Bank classification of economies as well as the Global Burden of Disease Socio-demographic Index. The findings show that oral conditions remain a substantial population health challenge. Globally, there were 3.5 billion cases (95% uncertainty interval [95% UI], 3.2 to 3.7 billion) of oral conditions, of which 2.3 billion (95% UI, 2.1 to 2.5 billion) had untreated caries in permanent teeth, 796 million (95% UI, 671 to 930 million) had severe periodontitis, 532 million (95% UI, 443 to 622 million) had untreated caries in deciduous teeth, 267 million (95% UI, 235 to 300 million) had total tooth loss, and 139 million (95% UI, 133 to 146 million) had other oral conditions in 2017. Several patterns emerged when the World Bank’s classification of economies and the Socio-demographic Index were used as indicators of economic development. In general, more economically developed countries have the lowest burden of untreated dental caries and severe periodontitis and the highest burden of total tooth loss. The findings offer an opportunity for policy makers to identify successful oral health strategies and strengthen them; introduce and monitor different approaches where oral diseases are increasing; plan integration of oral health in the agenda for prevention of noncommunicable diseases; and estimate the cost of providing universal coverage for dental care.

Community-level predictors of Australian children's dental caries and injury

BACKGROUND

Social determinants of oral health are complex and have been described by conceptual frameworks. A widely embraced model of children's oral health was published by Fisher-Owens et al. (2007), identifying theoretical constructs influencing oral health. The current study aimed to investigate community-level constructs described in the conceptual model.

METHODS

The Longitudinal Study of Australian Children is a cross-sequential dual cohort study, with a representative sample (n = 10090) of Australian children. Generalized estimating equations were applied to model seven waves of carer-reported oral health and community measures.

RESULTS

In the final model, children living in Queensland had a 1.48 (CI 1.35-1.62) increased odds of dental caries over time. Children in low socio-economic status (SES) areas (OR 1.32 CI 1.20-1.44) had an increased odds of caries. The state of Queensland (OR 1.24 CI 1.05-1.46) and poor neighbourhood liveability (OR 1.17 CI 1.05-1.31) were predictors of dental injury.

CONCLUSION

By modelling available community measures, this study found SES and rurality were predictors of caries over childhood. Our results highlight the difficulty of applying conceptual models to oral health. The use of qualitative studies and realist reviews should be considered to complement statistical models to provide contextualized insights into funding, policy and service delivery on children's oral health.

Salivary characteristics and dental caries experience in remote Indigenous children in Australia: a cross-sectional study

Background

While associations between salivary characteristics and dental caries have been well studied, we are not aware of this being assessed in a remote Indigenous child population, where lifestyles may be different from urban children. Our aim was to assess associations between caries experience and putative biomarkers in saliva, accounting for oral hygiene and dietary habits.

Methods

Children attending schools in an Indigenous community in remote north Queensland, Australia were invited to an oral examination by qualified and calibrated examiners. Salivary flow rate, pH, buffering capacity and loads of mutans streptococci (MS), lactobacilli (LB) and yeasts were determined. Also, data on tooth brushing frequency and soft drinks consumption were obtained via a questionnaire. Caries experience was recorded by the International Caries Detection and Assessment System (ICDAS-II), and quantified as decayed, missing and filled surfaces. Relationships between the salivary variables and the cumulative caries experience (dmfs+DMFS) in the deciduous and permanent dentitions were examined by multivariate analyses to control the effect of confounders.

Results

The mean cumulative decayed (DS + ds), missing (MS + ms) and filled (FS + fs) surfaces were 3.64 (SD: 4.97), 1.08 (4.38) and 0.79 (1.84) respectively. Higher salivary MS and LB counts, low tooth brushing frequency and daily soft drink consumption were significantly related to greater caries experience. Caries experience was about twice in those with ≥10^5 CFU/ml saliva counts of MS (mean = 6.33, SD: 8.40 vs 3.11, 5.77) and LB (7.03, 7.49 vs 4.41, 8.00). In the fully-adjusted multivariate model, caries experience in those with higher counts of MS and LB were 51 and 52% more than those with lower counts.

Conclusions

As with studies in other populations, childhood salivary counts of MS and LB were significantly associated with greater caries experience in this remote Indigenous community. To address the serious burden of oral disease, we are researching ways to promote a healthy oral environment by encouraging good dietary habits, and emphasising the importance of daily tooth brushing with a fluoridated toothpaste. Our ongoing longitudinal studies will indicate the success of measures employed to reduce the counts of bacteria closely associated with cariogenesis and their impact on caries increment.

Trial registration

Australian New Zealand Clinical Trials Registry (ANZCTR), No: ACTRN12615000693527; date of registration: 3rd July 2015.

Endodontic treatment-related antibiotic prescribing patterns of South African oral health professionals

AIM

To assess the antibiotic prescribing patterns of South African dentists for patients undergoing endodontic treatment.

METHODOLOGY

This study used data from 2013 health insurance claims submitted by South African oral health professionals to determine the antibiotic prescribing patterns related to endodontic treatment. A logistic regression model was used to test the fully adjusted statistical significance of the association between the exploratory variables (gender, age group, event type, abscess treatment, chronic health) and the dependent variable (antibiotic prescription). Odds ratios with 95% confidence intervals (CI) are reported, and a 95% CI excluding 1 was considered statistically significant.

RESULTS

Almost 10% of endodontic treatments were prescribed an antibiotic. There were no significant differences in prescribing patterns by gender, age and chronic health status. Prescriptions were more common at the preparatory stage (9.4%) of root canal treatment compared to the therapy (4.7%) and canal filling (2%) stages. Patients who received apical surgery (OR = 2.28; 95% CI 1.38-3.76) and treatment of an abscess (OR = 2.57; 95% 1.82-3.63) had a significantly increased odds of being prescribed an antibiotic. Almost three-quarters of prescriptions were for narrow spectrum antibiotics.

CONCLUSION

The frequency of antibiotic prescribing by South African dental practitioners for patients undergoing endodontic treatment is relatively low and predominantly involved narrow spectrum antibiotics. It, however, remains important that antibiotics are only prescribed when clinically essential, such as when there are obvious systemic effects. These include fever above 37 degrees, malaise, lymphadenopathy, trismus, increase swelling, cellulitis, osteomyelitis and persistent infection. The wider dissemination and adherence to clear evidence-based prescribing guidelines for antibiotics in this clinical area are important.

Effectiveness of water fluoridation in caries reduction in a remote Indigenous community in Far North Queensland

BACKGROUND

Children in remote Indigenous communities in Australia have levels of dental caries much greater than the national average. One such, the Northern Peninsula Area of Far North Queensland (NPA), had an oral health survey conducted in 2004, shortly before the introduction of fluoridated, reticular water. Children were again surveyed in 2012, following five years exposure.

METHODS

An oral examination was conducted on all consenting children enrolled in schools across the community, using WHO Basic Oral Health Survey methodology.

RESULTS

Few teeth had restorations in both surveys. Age-weighted overall caries prevalence and severity declined from 2005 to 2012 by 37.3%. The effect was most marked in younger children, dmft decreasing by approximately 50% for ages 4-9 years; at age 6, mean decayed score decreased from 5.20 to 3.43. DMFT levels also decreased by almost half in 6-9 year olds. However, significant unmet treatment needs exist at all ages.

CONCLUSIONS

There has been considerable improvement in child dental health in the NPA over the past 6-7 years. In light of continued poor diet and oral hygiene, water fluoridation is the most likely explanation. The cost-effectiveness for this small community remains an issue which, in the current climate of political antagonism to water fluoridation in many quarters, requires continued study.

Trends and ethnic disparities in oral and oro-pharyngeal cancers in South Africa, 1992-2001

OBJECTIVE

To describe trends in the epidemiology of oral and of oro-pharyngeal (OAP) cancers in South Africa for the atest period available.

METHODS

Data were obtained from the South African pathology-based National Cancer Registry. All new cases of OAP cancers diagnosed and confirmed histologically from 1992 to 2001 are included for the ICD-10 sites C00 to C14, excluding those involving the major salivary glands (C07-C08) and the nasopharynx (C11). OAP cancer incidence is reported by demographics (gender, age, race/ethnicity) and the anatomical sites involved. The analysis on anatomical sites was restricted to squamous cell carcinomas.

RESULTS

Overall, males had a much higher OAP cancer incidence rate (world age-Standardised incidence rate [ASIR] = 7.01/100 000 per year) than females (ASIR = 1.99). However, among Asian/Indian South Africans, OAP cancer incidence was higher among females (ASIR = 4.60) than among males (ASIR = 3.80). OAP cancer, excluding those involving the lip, was highest among Coloureds (ASIR = 5.72) and lowest among Blacks (ASIR = 3.16). OAP cancer incidence was stable overall, but incidence rates increased significantly among Coloured South Africans over the period under review (p < 0.05). Cancer specifically involving the oro-pharyngeal was most common among Coloureds and showed an increasing trend during the period under review.

CONCLUSIONS

Variations in the incidence of OAP cancers by gender, race/ethnicity and anatomic site indicate a need for culturally-targeted reductions in major risk factors, including promoting tobacco cessation and prevention of risky alcohol use. The implications of the role of the human papillomavirus (HPV) in the prevention of squamous cell carcinomas involving the oro-pharyngeal in South Africa require further investigation.

Effects of fluoridated milk on artificial enamel carious lesions: a pH cycling study

OBJECTIVE

To investigate the relationship between concentration of fluoride in milk and its re-mineralizing efficacy, and to test whether increasing the volume of fluoridated milk has any effect on its re-mineralizing efficacy.

METHODS

Third molars were painted leaving a 1 mm window on the buccal and/or lingual surfaces. Artificial carious lesions were induced using a de-mineralizing solution. The teeth were then sectioned longitudinally. Specimens were randomly assigned to 15 groups according to different concentrations and volume; i.e., 2.5 ppm, 5 ppm, 7.5 ppm, 10 ppm, 15 ppm, 20 ppm, and 250 ppm of fluoride with 25 ml/section and 50 ml/section. De-ionized water and plain milk were used as controls. Sections were subjected to pH cycling for 20 days. Polarized light microscopy and micro-radiography were utilized to record the lesion characteristics before and after pH cycling.

RESULTS

Mean lesion depths decreased significantly in all the fluoride groups, and increased significantly in the control groups. There were no differences in percentage of lesion depth decrease when the volume was doubled for the same fluoride concentration. There were also no statistically significant differences between percentages of decrease in lesion depth when the concentration of fluoride in milk was increased.

CONCLUSION

Fluoridated milk demonstrated a remineralization efficacy on early enamel carious lesions. A 2.5 ppm fluoride milk concentration provided similar remineralization potential to that of higher fluoride concentration in milk.

Derivation and validation of a risk-factor model for detection of oral potentially malignant disorders in populations with high prevalence

BACKGROUND

Oral and pharyngeal cancers constitute the sixth most common type of cancer globally, with high morbidity and mortality. In many countries, most cases of oral cancer arise from long-standing, pre-existing lesions, yet advanced malignancies prevail. A new approach to early detection is needed. We aimed to validate a model for screening so that only high-risk individuals receive the clinical examination.

METHODS

A community-based case-control study (n=1029) in rural Sri Lanka assessed risk factors and markers for oral potentially malignant disorders (OPMD) by administering a questionnaire followed by an oral examination. We then developed a model based on age, socioeconomic status and habits of betel-quid chewing, alcohol drinking and tobacco smoking, with weightings based on odds ratios from the multiple logistic regression. A total, single score was calculated per individual. Standard receiver-operator characteristic curves were plotted for the total score and presence of OPMD. The model was validated on a new sample of 410 subjects in a different community.

RESULTS

A score of 12.0 produced optimal sensitivity (95.5%), specificity (75.9%), false-positive rate (24.0%), false-negative rate (4.5%), positive predictive value (35.9%) and negative predictive value (99.2%).

CONCLUSION

This model is suitable for detection of OPMD and oral cancer in high-risk communities, for example, in Asia, the Pacific and the global diaspora therefrom. A combined risk-factor score of 12.0 was optimal for participation in oral cancer/OPMD screening in Sri Lanka. The model, or local adaptations, should have wide applicability.

Competitive exclusion as a mode of action of a novel Bacillus cereus aquaculture biological agent

AIMS

To determine the contribution of potential modes of action of a Bacillus cereus aquaculture biological control agent in inhibition of the fish pathogen, Aeromonas hydrophila.

METHODS AND RESULTS

When B. cereus was tested in plate well inhibition studies, no production of antimicrobial compounds was detected. Bacillus cereus had a high growth rate (0.96 h(-1)), whereas Aer. hydrophila concentration decreased by c. 70% in co-culture experiments. In nutrient limitation studies, B. cereus had a significantly higher growth rate when cultured under glucose (P < 0.05) and iron (P < 0.01) limitation in comparison with Aer. hydrophila. Bacillus cereus glucose (0.30 g l(-1) h(-1)) and iron (0.60 mg l(-1) h(-1)) uptake rates were also significantly higher (P < 0.01) than the Aer. hydrophila glucose (0.14 g l(-1) h(-1)) and iron (0.43 mg l(-1) h(-1)) uptake rates. Iron uptake was facilitated by siderophore production shown in time profile studies where relative siderophore production was c. 60% through the late exponential and sporulation phases.

CONCLUSIONS

Competitive exclusion by higher growth rate, competition for organic carbon and iron, facilitated by siderophore production, could be identified as mechanisms of pathogen growth inhibition by B. cereus.

SIGNIFICANCE AND IMPACT OF THE STUDY

This study is the first elucidation of the mechanism of action of our novel B. cereus biological agent in growth attenuation of pathogenic Aer. hydrophila. This study enhances the application knowledge and attractiveness for adoption of B. cereus NRRL 100132 for exploitation in aquaculture.

Patterns and reasons for tooth extraction at the Winterveldt Clinic: 1998-2002

BACKGROUND

Tooth extraction is the most common form of dental treatment in developing countries despite significant advances in medicine and dentistry. Dental caries, periodontitis, orthodontics, trauma and prosthodontics are the main reasons for extractions.

OBJECTIVE

To determine the patterns of tooth extractions and the reasons for these extractions in a primary care dental clinic attached to a dental training institution.

METHODS

A descriptive, retrospective and quantitative study design was followed. Data was gathered from 3793 patient files to record the following variables: age, gender, type of tooth extracted and reason for the extraction.

RESULTS

Almost 60% of teeth extracted were lower and upper molars. The main reasons for extractions were dental caries (47.9%) and periodontitis (22.6%).

CONCLUSIONS

The findings of the study show an urgent need to reverse the trends in extractions and more emphasis should be placed on primary prevention in order to reduce tooth loss.

Prevalence and severity of periodontal disease: type 2 diabetics versus non-diabetics

OBJECTIVE

To compare the periodontal status of a group of diabetic Coloured and Black communities of South Africa with a non-diabetic group.

STUDY DESIGN

Sixty-seven type 2 diabetics (mean age: 49.3 +/- 8.97) and 67 non-diabetics (mean age: 47.6 +/- 8.85) were examined. The plaque index (P1I), gingival index (GI), probing depth (PD) and clinical attachment loss (CAL) were recorded on Ramfjord index teeth or their substitutes. Previous dental care, smoking status, alcohol consumption and socio-economic status were also assessed.

RESULTS

Diabetics had significantly higher mean GI (p = 0.001), PD (p = 0.031) and CAL (p = 0.022) than non-diabetics. The mean P1I (p = 0.531) was not significantly different between the two groups.

CONCLUSION

This study showed that diabetics had more severe and a higher prevalence of periodontal disease. Diabetics and their health care givers should be informed of these findings so that diabetics can seek early management of periodontal disease.

Effect of an exponential feeding regime on the production of Rhodotorula araucariae epoxide hydrolase in Yarrowia lipolytica

AIMS

To evaluate the effect of and exponential feeding regime on the production of epoxide hydrolase (EH) enzyme in recombinant Yarrowia lipolytica in comparison to a constant feed strategy.

METHODS AND RESULTS

An exponential feed model was developed and fermentations were fed at six different exponential rates. A twofold increase in EH productivity and a 15% increase in volumetric EH activity was obtained by applying exponential glucose feed rates in fed-batch cultivation. These responses were modelled to obtain a theoretical optimum feed rate that was validated in duplicate fermentations. The model optimum of 0.06 h(-1) resulted in a volumetric EH activity of c. 5500 U l(-1) h(-1) and a maximum activity of 206,000 U l(-1). This correlated well with model predictions, with a variance of <10%.

CONCLUSIONS

The use of an exponential feed strategy at a rate of 0.06 h(-1) yielded best results for all key responses which show a clear improvement over a constant feed strategy.

SIGNIFICANCE AND IMPACT OF THE STUDY

The study was the first evaluation of an exponential feed strategy on recombinant Y. lipolytica for the production of EH enzyme. The results suggest a strategy for the commercial production of a valuable pharmaceutical enzyme.

Fissure sealants on permanent first molars--consequences of a one-year delay

OBJECTIVE

The objective of this study was to compare the dental caries status of the occlusal surfaces of permanent first molars of Grade 2 (7-8 years of age) children who kept, and those who missed their Grade 1 (6-7 years of age) dental public health clinic appointment.

DESIGN

The data were obtained from the records of schoolchildren attending the clinic for a comprehensive dental public health programme, with emphasis on fissure sealing permanent first molars. The records were grouped into those who had attended the clinic the previous year and those who did not attend.

RESULTS

The permanent first molars were significantly more likely to be carious in children who missed the Grade 1 appointment compared to those who kept the appointment.

CONCLUSION

A one year delay in fissure sealing the occlusal surfaces of permanent first molars substantially increased the likelihood of dental caries on these teeth.

Early-phase dental students' motivations and expectations concerning the study and profession of dentistry

This study investigated the career choice and aspirations of early phase dental students in the four dental schools in South Africa, namely the University of the Western Cape (UWC), University of the Witwatersrand (Wits), University of Limpopo (Medunsa) and University of Pretoria (UP). Willing participants completed a self-administered questionnaire (n=184). Motivations for entering a dentistry programme were similar across race and university, with wanting a secure job most often stated as an important factor. For a third of respondents, dentistry was not a first choice. Amongst the White students, it was a first choice for 82% compared with 59% amongst Black Africans. Expected income five-years after graduation also differed significantly across race and university, with White and UP students expecting to earn considerably higher than the others. About 36% of students were concerned about the levels of personal debt related to studying, with the White and Asian students less concerned. Those who expected lower levels of income from the profession were more concerned about personal debts. Most students planned to enter general dental practice (GDP) after community service, almost all White and Wits students expressed this intention, compared with only 35% of Black Africans and 39% of Medunsa students. Orthodontics and Maxillofacial & Oral Surgery were the most popular specialities of choice. The professional attribute "Has a friendly manner and good relationship with patients" was ranked high most often. In conclusion, career advice may not need to be tailored differently for the different racial groups. There is however a need for further investigations on how to address the concerns of financial security which may be realised by the practice of dentistry, and in particular the racial disparities observed in expectations of the profession. This study further highlights the need for government financial assistance for students from under-represented groups.

Support for Social Health Insurance in South Africa

A national cross-sectional survey was carried out in South Africa to gain an understanding of the perceptions and priorities of the likely members of a future social health insurance (SHI). More than 1,000 employees were interviewed in a variety of employment sectors, including state and parastatal organisations, formal and informal private sectors. This article reports on respondents’ level of support for a compulsory contribution towards a hospital insurance scheme funding care at public sector hospitals in South Africa.

The results showed that only 11 per cent of employees supported an SHI scheme if public hospitals remain as they are. Support increased to 53 per cent if preferential access to treatment was offered to those contributing to the scheme. Support was almost unanimous (87 per cent) if public hospitals were improved. The levels of support differed by current type of health insurance.

Thus, support for a compulsory SHI tax to fund care in public hospitals was conditional upon either improving the hospitals or providing differential treatment to contributing members. If one or both of these conditions are not met, its long-term success will be compromised.

A national human resources plan for oral health: is it feasible?

The South African Department of Health has prepared "A National Human Resources Plan for Health". This plan proposes that the number of dentists produced annually be decreased from 200 to 120, the number of dental therapists increased from 25 to 600 and the number of oral hygienists from 70 to 150.

OBJECTIVE

To assess the feasibility of this output plan.

METHODS

This paper reviewed the national oral health status and needs, as well as the National Oral Health Strategy, and then assessed the appropriateness of the plan in relation to these findings. The current numbers of students in training and expected production over the next few years was analysed and the feasibility of the proposed production outputs against the current outputs. The current distribution of oral health personnel was also investigated.

RESULTS

Substantial parts of the national oral health needs and strategy can be met and implemented by any of the three oral health professionals being trained. More than 80% of oral health professionals are urban-based and in the private sector. The current production of the five dental training institutions is about 320, compared to the proposed output of almost 900 in the plan. With institutions running at near full capacity, the proposed production numbers are not feasible in the short term. However a number of issues need further investigation: which oral health professional is best suited to meet the oral health needs of the population and implement the national oral health strategy, that will make a significant impact on the oral health of the population; how many oral health professional do we require and will the plan address issues of access to services and appropriateness (evidence-based, prevention bias) of care provided?

CONCLUSION

There is a need for further investigation of the plan in consultation with all stakeholders, especially its cost implications and alternative strategies to reduce the incidence of oral diseases in the country.

The impact of new complete dentures on oral health-related quality of life

OBJECTIVE

To investigate the relationship between complete dentures and oral health-related quality of life (OHRQoL).

METHOD

Seventy-six patients were conveniently selected from the waiting list for complete dentures. At the first visit (pre-treatment) the patients were interviewed using the Oral Health Impact Profile for Edentulous Patients (OHIP-EDENT). Sixty-three of these patients were interviewed telephonically 2 to 3 months after receiving their new complete dentures (post-treatment).

RESULTS

Mean domain scores were significantly lower post-treatment for psychological discomfort and disability, social disability and handicap.

CONCLUSION

This study shows that after the provision of a new set of complete dentures the OHRQoL of patients improved significantly on four of the seven domains for the first 2 to 3 months post-insertion.

Professionally applied topical fluoride and fissure sealants: matching insurance claims with evidence

OBJECTIVE

The purpose of this study was to assess the extent to which medical aid schemes are funding evidence-based dental care, specifically assessing claims patterns for professionally applied topical fluoride and fissure sealant treatments to the beneficiaries of a large South African medical aid scheme. The rising costs of dental care provide the impetus to review spending patterns to assess whether resources are being utilised optimally. The emergence of evidence-based dentistry offers an important tool in this regard.

METHODOLOGY

The 2005 membership and claims data of a large South African medical scheme were analysed for the period 1 January 2005 to 31 December 2005. The claim patterns for two dental caries preventive interventions with different levels of evidence were assessed and compared for two age groups: under 20 years of age and 20 and above.

RESULTS

About 30% received a topical fluoride application, equally provided to both age categories. Less than 3% of all who visited the dentists received at least one sealant. Of those under 20 years of age, only 10% received this proven preventive intervention.

CONCLUSIONS

This study highlights the need to substantially increase the provision of fissure sealants to children with erupting first (5-7 year olds) and second (11-13 year olds) permanent molar teeth and decrease the provision of professionally applied fluoride applications to those outside of specifically identified caries-risk groups. This study further illustrates the potential of applying evidence-based dentistry research findings to assessing the appropriateness of claim patterns as well as the funding thereof.

Dental specialist training in South Africa--demographic characteristics 1985-2004

This short communication complements a recently published dental undergraduate analysis, and analyses the demographic profile of dental specialists trained from 1985-2004, as well as that of the registrars in training (in 2005). A total of 309 dental specialists were trained from 1985-2004, of these 86% were males and 74% White. Of the registrars, two-thirds are males and a quarter Black. The dental faculties and the Health Professions Council of South Africa (HPCSA) face a significant challenge to find innovative ways to address these disparities, as well as the urban/rural and private/public sector maldistribution of dental specialists, and to develop a more rational basis for training dental specialists for the country. Dealing with these disparities should improve access to dental specialist care for the poor and rural populations.

Scientific. Risk of intraoral cancer associated with tobacco and alcohol--a case-control study

OBJECTIVES

The study examined the role of tobacco, alcohol consumption and their synergistic effect on the aetiology of intraoral cancer.

DESIGN

A hospital-based, analytical case-control study.

SUBJECTS

Information was collected from 67 intraoral cancer patients attending a cancer unit (cases) and 67 controls attending other clinics in the same hospital. Cases and controls were individually matched for age, gender and ethnicity.

METHODS

A structured interview was used to collect the data on items related to smoking status and alcohol consumption.

RESULTS

The odds of developing intraoral cancer were 41 times (OR = 4.63; 95% CI: 1.74-12.30) higher for current smokers compared to non-smokers. The odds of developing intraoral cancer were eight times higher for past drinkers (OR = 8.59; 95% CI: 2.96-24.92) and current drinkers (OR = 8.54; 95% CI: 3.55-20.50) compared to non-drinkers. Consumers of both tobacco and alcohol were ten times more likely to develop intraoral cancer compared to those who do neither.

CONCLUSIONS

The risk of intraoral cancer arising from use of alcohol and tobacco, icant. The findings of the study strongly endorse the rationale behind efforts by the South African government to implement strict tobacco legislation and campaign for responsible drinking.

Gender and race distribution of dental graduates (1985-2004) and first year dental students (2000-2005) in South Africa

This paper, written at the close of a decade of democracy in South Africa, sets out to analyse the demographic profile of dental graduates from 1985-2004 at the five Faculties/Schools of Dentistry in South Africa. A comparison of the profiles for the pre-democracy (1985-1994) and post-apartheid (1995-2004) periods has been made. The demographic profile of first year dental students from 2000-2005 is also presented. From 1985-1994, most dental graduates were male (79%), but this changed substantially from 1995-2004, with females comprising 46% of those graduating. In the pre-democracy period, more than three-quarters of all graduates were White (78%), decreasing to 46% in the post-apartheid period under review. Black graduates increased from 6% to 24% across the two study periods. Amongst the first year dental student intake from 2000-2005, females comprised 57%. There was an almost equal distribution across the White, Black and Asian groups. Dental faculties/schools have made important strides in transforming the demographic profile of their students. The percentage of Black graduates, however, needs to be significantly increased if it is to reflect the national population. Faculties/schools must further ensure that able students from working class background are identified and considered for acceptance into the undergraduate dental programme, and should then be offered the necessary academic and mentoring support to enable success.

A review of paediatric maxillofacial injuries--a hospital-based study

This study describes the patient profile with maxillofacial injuries attending a trauma unit at a children's hospital. A retrospective record-based analysis was carried out of children (less than 13 years of age) presenting with maxillofacial injuries from January 1991 to December 2001. Of the almost 90,000 trauma records, 13% of children presented with maxillofacial injuries. 60% were boys, with a quarter less than 3 years of age. Most presented with superficial lacerations and abrasions. The face (other than the facial bones) and the mouth/oropharnyx were most often injured. Injuries were mainly caused by falls from a variety of heights and transport-related injuries. Almost 60% of traffic-related injuries involved children as pedestrians being struck by a motor vehicle and 20% were cycle-related. Almost 70% of injuries occurred in or around their own home. Maxillofacial injuries in children are a significant cause of morbidity and its prevention especially in the home and streets needs urgent attention.

Access to health care in South Africa--the influence of race and class

OBJECTIVES

The first democratic government elected in South Africa in 1994 inherited huge inequities in health status and health provision across all sections of the population. This study set out to assess the impact of the new government's commitment to address these inequities and implement policies to improve population health in general and address inequalities in health care in particular.

DESIGN

A 1998 household survey assessed many aspects of health delivery, including their own perceived and actual access to health care among different segments of South African society.

RESULTS

Race was the main predictor of perceived changes in access to health care, with black, coloured-and Indian respondents significantly more likely to feel that access had improved since 1994, compared with white respondents. Socio-economic status (SES) was the main predictor of actual access to health care, with low and middle SES classes significantly less likely to access care when ill.

CONCLUSIONS

One-third of respondents perceived health care access to have improved between 1994 and 1998, and this response was partially determined along racial lines. About one-quarter reported an inability to access health care when they required it, and this response was partially determined along socio-economic lines. This set of contrasting responses suggests that at a political level perceptions are largely influenced by race, but at the operational level actual access is influenced by SES.

Profile of children with head injuries treated at the trauma unit of Red Cross War Memorial Children's Hospital, 1991 - 2001

OBJECTIVE

To describe the profile of childhood head injury patients treated in a trauma unit.

DESIGN

A retrospective record-based study.

SETTING

The trauma unit of the Red Cross War Memorial Children's Hospital.

SUBJECTS

Children (under 13 years of age) presenting with head injuries between January 1991 and December 2001.

RESULTS

Of the almost 94 000 records, more than one-third were children presenting with head injuries. Fifty-nine per cent were boys, with more than half the sample under 5 years of age. The majority of children presented with superficial lacerations and abrasions, mostly affecting the scalp and skull. Injuries were mainly caused by falls from a variety of heights, and traffic-related injuries. Almost two-thirds of traffic-related injuries involved children as pedestrians being struck by a motor vehicle. More than 60% of injuries occurred in or around the child's own home.

CONCLUSIONS

Head injuries in children are a significant cause of morbidity. Prevention, especially in the home and on the streets, needs urgent attention.

African countries propose a regional oral health strategy: The Dakar Report from 1998

It is clear that the African region faces a number of serious oral diseases, either because of their high prevalence or because of the severe tissue damage or death that can occur. Previous approaches to oral health in Africa have failed to recognise the epidemiological priorities of the region or to identify reliable and appropriate strategies to assess them. Efforts have consisted of an unplanned, ad hoc and spasmodic evolution of curative oral health services. This document focuses on the most severe oral problems that people have to live with like noma, oral cancer and the oral consequences of HIV/AIDS infection. It proposes a strategy for assisting member states and partners to identify priorities and interventions at various levels of the health system, particularly at the district level. The strategy aims at strengthening the capacity of countries to improve community oral health by effectively using proven interventions to address specific oral health needs. The strategy identifies five main 'programmatic areas', including (i) the development of national oral health strategies and implementation plans, (ii) integration of oral health in other programmes, (iii) delivery of effective and safe oral health services, (iv) regional approach to education and training for oral health, and (v) development of effective oral health management information systems. Many of the programmatic areas share similar characteristics described as a 'strategic orientation'. These strategic orientations give effect to the concepts of advocacy, equity, quality, partnership, operational research, communication and capacity building. The WHO Regional Committee for Africa (RC) is invited to review the proposed oral health strategy for the African region for the period 1999-2008 and provide an orientation for the improvement of oral health in member states in the region.

Behavioural characteristics and accidents: findings from the Health Survey for England, 1997

This study analysed the relationship between major and minor accidents, and major accidents involving a moving vehicle, and behavioural and emotional factors in children, aged 4-15 years, using the Strengths and Difficulties Questionnaire (SDQ), and adjusting for demographic, socio-economic and family type factors. Data from a large representative national sample of about 6000 children were analysed using simple and multiple logistic regression. The analysis shows that the prevalence of SDQ scales, such as hyperactivity and conduct disorder were significantly higher in boys, lower social classes and step- and single-parent families. After adjusting for the demographic, socio-economic and family type factors, children who scored borderline or high for hyperactivity were almost two times more likely to report having major accidents. Children who scored high for hyperactivity and emotional symptoms were one and a half times more likely to report having minor accidents. For major accidents involving moving vehicles, the relationships with the behavioural and emotional factors were generally stronger than for major accidents in general. Hyperactivity, in particular, was significantly associated with the occurrence of major and minor accidents, and major accidents involving moving vehicles. The behavioural risk factors were significantly more common in the lower social classes, families receiving benefits and step- and single-parent families.

Oral diseases and socio-economic status (SES)

OBJECTIVE

To determine the association between social, economic and behavioural risk factors and national prevalences of: oral cancer, dental caries (12-year-olds) and destructive periodontal disease (35-44-year-olds).

DATA SOURCES

Sources for the social and economic parameters were the UN Development Program; the behavioural risk factors' source was the World Health Organization, the UN Food and Agricultural Organization and the World Atlas of History. Oral diseases data came from UICC Globocan and the World Health Organization databases.

DATA EXTRACTION

Data were extracted by hand from official publications.

DATA SYNTHESIS

Data were synthesized and analyzed in sequence using SPSS, Pearson's correlation coefficient and multiple regression analyses.

CONCLUSIONS

There is a discernable association between the three oral diseases and the variables selected, which varies in strength, being strongest for chronic destructive periodontitis and weakest for oral cancer. Dental caries lies in between. The degree to which variables account for differences in the three oral diseases between the countries studied is striking, being insignificant for oral cancer incidence, modest for oral cancer mortality, stronger for dental caries and strongest for destructive periodontal disease. Removing variables with strong co-linearity with the Human Development Index has little effect on the regression coefficients.

A retrospective analysis of gunshot injuries to the maxillo-facial region

This study analysed the prevalence, demography, soft- and hard-tissue injury patterns, management and complications of gunshot injuries to the maxillo-facial region in 301 patients treated at Groote Schuur Hospital, Cape Town. The number of patients presenting with maxillo-facial injuries caused by gunshot increased over the 15-year study period. The majority were caused by civilian type low-velocity hand-guns and were purposefully and intentionally inflicted by others. Males in their third decade of life and of low socioeconomic status were most often the victims. The wounding effects of these low-velocity injuries were characteristic--small rounded entrance wounds, causing fragmentation of teeth and comminution of the underlying bone, usually without any exit wounds. A comminuted displaced type of fracture pattern was most frequently observed. Special investigations included plain film radiographs with more sophisticated investigations being requested where indicated. Definitive surgical management was initiated by early soft-tissue debridement. Both the mandibular and maxillary fractures had more open than closed reductions. Bone continuity defects as a result of the initial injury were usually reconstructed secondarily using free autogenous bone grafts. All the patients received anti-tetanus toxoid on admission and the majority received antibiotic treatment. The most common complications were sepsis, ocular and neurological complications and limitation of mouth opening. The postoperative sepsis rate was high (19%). The wounding effects of these low-velocity missile injuries are devastating and pose a treatment challenge to the maxillo-facial surgeon.

Dental caries status of 5-7 year old children in three districts in Tanzania, Uganda and Mozambique

This paper presents the baseline data of a longitudinal study assessing the dental caries status of 5-7 year old children in Tanzania, Uganda and Mozambique. Approximately one hundred 5-7 year-old-children from randomly selected schools in each of three locations (formal urban, informal urban and rural) were examined using the 1997 WHO Oral Health Survey Criteria. Thirty nine percent of the entire sample were found to bc caries-free, however this differed from location to location and from country to country. The overall mean dmft was 2.4 (SD 2.8), with the decayed component being 2.0 and the missing component 0.4. Of the children examined, only three had filled teeth. The mean dmft was significantly higher (p-value < 0.05) in Tanzania and Uganda than in Mozambique. There were also significant differences in the mean dmft between the various locations in Uganda and Mozambique. The prevalence of dental caries was not consistent across the formal urban, informal urban and rural locations in the three countries studied. It is thus essential to desegregate oral health status data to the most local level possible.

Dental caries, socio-economic development and national oral health policies

A relationship between a population's level of socio-economic development and dental caries has often been assumed. Proxy measures such as sugar consumption have been used to reflect this. This study tests the hypothesis that there is a relationship between dental caries and the level of socio-economic development, using recent international data. It goes on to explore the implications of this relationship for the development of national oral health policies. Dental caries data was obtained from the WHO, Global Oral Epidemiology Data Bank for the period 1981-1996. Socio-economic data was obtained from the United Nations Development Programme (UNDP). Countries were ranked according to the Human Development Index (HDI) and their GNP. The study confirms the existence of a relationship between dental caries and development. Caries is a good proxy measure for socio-economic development. Countries in the throes of socio-economic transition have the highest DMFT scores.

A comparison of service profiles in alternative dental care delivery systems

The financial crisis within the health care sector has resulted in the search by medical benefit funds of worker organisations for cost-effective alternatives to the private health care sector. This study compares the profile of services rendered to members of a union medical benefit fund by an 'in house' dental clinic and private dental practitioners. A total of 2,858 union clinic claims and 10,811 private practitioner accounts were selected. Each treatment code was categorised into either preventive, restorative, extraction or denture services. For the union clinic and private dental practitioners a total of 3,021 and 15,853 treatment codes respectively were included in the analysis. Significant differences were found in the profile of services rendered by the union clinic and private dental practitioners. The union clinic provided predominantly preventive and denture-related treatment compared with private practitioners who provided mainly preventive and extraction services. Members and their dependants are far more likely to have dentures made through the dental clinic (the odds of having dentures made at the clinic were 4.67 times the odds of having dentures made through private practitioners). On the other hand, members were more likely to receive all the other services (restorative, preventive and extractions) from private practitioners. However, the nature of the study design and the findings do not allow conclusions to be drawn regarding whether these differences were due to demand or supplier influences.

A comparison of dental caries status by surface and treatment needs of 5-7 year old children in Tanzania, Uganda and Mozambique

This paper presents the baseline data of a longitudinal study assessing the dental caries status by surface and the treatment needs of 5-7 year old children in Tanzania, Uganda and Mozambique. Approximately one hundred 5-7 year old children were examined from randomly selected schools in each of three locations (urban formal, urban informal and rural) in each country. The mean dmfs score for the entire sample was 5.1 (7.5), with the mean number of decayed surfaces being 3.4 and missing surfaces 1.7. The mean dmfs score was significantly higher (p-value < 0.05) in Uganda, especially in the urban informal location. The teeth most commonly decayed were the lower molars and upper central incisors. Most of the teeth decayed needed to be extracted. The findings in this study correlate with the few other studies assessing dental caries by surface in east and southern African countries.