Mohd Masood

The Magnitude of Tobacco Smoking-Betel Quid Chewing-Alcohol Drinking Interaction Effect on Oral Cancer in South-East Asia. A Meta-Analysis of Observational Studies

Tobacco smoking, betel quid chewing and alcohol drinking are oral cancer risk factors. Observational studies unanimously report that oral cancer risk in smoking-drinking-chewing exposed subjects is exceptionally high. However, none of them assessed the fractions of this risk attributable to the three individual risk factors and to the smoking-drinking-chewing interaction. The present study sought to assess the magnitude of the smoking-drinking-chewing interaction effect on oral cancer. A meta-analysis of observational South-East Asian studies which reported oral cancer odds ratios (ORs) stratified for smoking-drinking-chewing exposures was performed. The pooled ORs were estimated and controlled for quality, heterogeneity, publication bias and inclusion criteria. The smoking-drinking-chewing interaction effect was estimated through the pooled Relative Excess Risk due to Interaction (RERI, excess risk in smoking-drinking-chewing exposed individuals with respect to the risk expected from the addition of the three individual risks of smoking, drinking and chewing). Fourteen studies were included with low between-study heterogeneity. The pooled ORs for smoking, drinking, chewing, smoking-drinking-chewing, respectively were 3.6 (95% confidence interval −95% CI, 1.9–7.0), 2.2 (95% CI, 1.6–3.0), 7.9 (95% CI, 6.7–9.3), 40.1 (95% CI, 35.1–45.8). The pooled RERI was 28.4 (95% CI, 22.9–33.7). Among smoking-drinking-chewing subjects, the individual effects accounted for 6.7% (smoking), 3.1% (drinking), 17.7% (chewing) of the risk, while the interaction effect accounted for the remaining 72.6%. These data suggest that 44,200 oral cancer cases in South-East Asia annually occur among smoking-drinking-chewing exposed subjects and 40,400 of these are exclusively associated with the interaction effect. Effective oral cancer control policies must consider concurrent tobacco smoking, alcohol drinking, betel quid chewing usages as a unique unhealthy lifestyle.

Impact of malocclusion on oral health related quality of life in young people

BackgroundThe objectives for this study were to assess Oral Health Related Quality of Life (OHRQoL) in young people aged 15–25 who sought orthodontic treatment, and to measure the association between orthodontic treatment need (using the IOTN), sex, age and education level, and oral health related quality of life (OHRQoL).MethodsSurvey of a consecutive series of 323 young adults aged 15 to 25 years, attending orthodontic clinics at the Faculty of Dentistry, Universiti Teknologi MARA. Participants completed the Oral Health Impact Profile-14 (OHIP-14) and had a clinical examination including the Index of Orthodontic Treatment Need- Dental Health Component (IOTN-DHC). Data analyses included descriptive statistics, One-way ANOVA and bivariate and multivariate regression models.ResultsThe mean overall score (± SD) for OHIP-14 in young people aged 15–25 was 22.6 ± 12.5. The psychological discomfort domain was the domain where highest impact was recorded with a mean (± SD) of 4.0 ± 1.9. The regression analyses showed a significant association of IOTN-DHC with overall OHIP-14 score (p < 0.05). Although females reported a slightly higher impact than males, this was not significant in both bivariate and multivariate analyses. Age group had a significant negative association with overall OHIP-14 score (p < 0.05). The 15–18 year old group showed the highest impact on their quality of life due to malocclusion. Participants with a university education report a significantly higher impact on OHRQoL as compared to participants with only secondary education.ConclusionMalocclusion has a significant negative impact on OHRQoL and its domains. This is greatest for the psychological discomfort domain. Younger people and those with a university education report higher levels of impact. There was no reported difference in impact between male and females.

An appraisal of the quality of published qualitative dental research.

OBJECTIVES To appraise the quality of published qualitative research in dentistry and identify aspects of quality, which require attention in future research. METHODS Qualitative research studies on dental topics were appraised using the critical appraisal skills programme (CASP) appraisal framework for qualitative research. The percentage of CASP criteria fully met during the assessment was used as an indication of the quality of each paper. Individual criteria were not weighted. RESULTS Forty-three qualitative studies were identified for appraisal of which 48% had a dental public health focus. Deficiencies in detail of reporting, research design, methodological rigour, presentation of findings, reflexivity, credibility of findings and relevance of study were identified. Problems with quality were apparent irrespective of journal impact factor, although papers from low impact factor journals exhibited the most deficiencies. Journals with the highest impact factors published the least qualitative research. CONCLUSIONS The quality of much of the qualitative research published on dental topics is mediocre. Qualitative methods are underutilized in oral health research. If quality guidelines such as the CASP framework are used in the context of a thorough understanding of qualitative research design and data analysis, they can promote good practice and the systematic assessment of qualitative research.

Need of minimal important difference for oral health-related quality of life measures

Demand and use for oral health-related quality of life (OHRQoL) instruments have increased in recent years in both research and clinical settings. These instruments can be used to measure patients health status or detect changes in a patients health status in response to an intervention or changes in disease trajectory. Ensuring universal acceptance of these measures requires easy interpretation of its scores for clinicians, researchers, and patients. The most important way of describing and interpreting this significance of changes in OHRQoL is through the establishment of minimal important difference (MID). The minimally important difference represents the smallest improvement considered worthwhile by a patient. A comprehensive search of published literature identified only 12 published articles on establishment of MID for OHRQoL measures. This scarcity of published studies on MID encourages the need of appropriate interpretation and describing patient satisfaction in reference to that treatment using MID. Anchor- and distribution-based methods are the two general approaches that have been proposed and recommended to interpret differences or changes in OHRQoL. Both of these methods of determining the MID have specific shortcomings; therefore, it is proposed to adopt triangulation approaches in which the methods are combined. The objective of this review is to summarize the need for, importance of, and recommendations for methods of establishing MID for OHRQoL measures.

Assessment of dental caries predictors in 6-year-old school children - results from 5-year retrospective cohort study

BackgroundThis was a retrospective cohort study undertaken to assess the rate and pattern of dental caries development in 6-year-old school children followed-up for a period of 5 years, and to identify baseline risk factors that were associated with 5 years caries experience in Malaysian children.MethodsThis 5-years retrospective cohort study comprised primary school children initially aged 6 years in 2004. Caries experience of each child was recorded annually using World Health Organization criteria. The rates of dental caries were recorded in prevalence and incidence density of carious lesions from baseline to final examination. Risk assessment was done to assess relative risk for caries after 5 years in children with baseline caries status. Simple and multiple logistic regression analysis were performed to identify significant independent risk factors for caries.ResultsThe sample consisted of 1830 school children. All components of DMFT showed significant differences between baseline and final examination. Filled teeth (FT) component of the DMFT showed the greatest increases. Results revealed the initial baseline caries level in permanent dentition was a strong predictor for future caries after 5 years (RR=3.78, 95% CI=3.48-4.10, P<0.001). Logistic regression analysis showed significant association between caries occurrence and residence (urban/rural) (OR=1.80, P<0.001). However, it was not significantly associated with gender and ethnicity. The incidence density of caries, affected persons (IDp) observed from baseline and after 5 years was 5.80 persons/100 person-year of observation. The rate of new caries-affected tooth (IDt) in the period from baseline and after 5-years was 0.76 teeth/100 teeth-year of observation.ConclusionThe majority of 12-year-old school children (70%) were caries-free and most of the caries were concentrated in only a small proportion (30%) of them. We found that the presence of caries in permanent teeth at the age of 6 years was a strong predictor of future caries development in this population. The strong evidence of early permanent teeth caries at six years old to predict future caries incidence at 12-year-olds, which could be obtained at almost no cost, questions the need for and cost-effectiveness of expensive technology-based commercial caries predictions kits.

Impact of national income and inequality on sugar and caries relationship

Objective: The aim of this study was to examine the impact that national income and income inequality in high and low income countries have on the relationship between dental caries and sugar consumption. Methods: An ecological study design was used in this study of 73 countries. The mean decayed, missing, or filled permanent teeth (DMFT) for 12-year-old children were obtained from the WHO Oral Health Country/Area Profile Programme. United Nations Food and Agricultural Organization data were used for per capita sugar consumption. Gross national incomes per capita based on purchasing power parity and the Gini coefficient were obtained from World Bank data. Bivariate and multivariate linear regression analysis was performed to estimate the associations between mean DMFT and per capita sugar consumption in different income and income inequality countries. Results: Bivariate and multivariate regression analysis showed that countries with a high national income and low income inequality have a strong negative association between sugar consumption and caries (B = –2.80, R2 = 0.17), whereas countries with a low income and high income inequality have a strong positive relationship between DMFT and per capita sugar consumption (B = –0.89, R2 = 0.20). Conclusion: The relationship between per capita consumption of sugar and dental caries is modified by the absolute level of income of the country, but not by the level of income inequality within a country.

Household expenditure for dental care in low and middle income countries.

This study assessed the extent of household catastrophic expenditure in dental health care and its possible determinants in 41 low and middle income countries. Data from 182,007 respondents aged 18 years and over (69,315 in 18 low income countries, 59,645 in 15 lower middle income countries and 53,047 in 8 upper middle income countries) who participated in the WHO World Health Survey (WHS) were analyzed. Expenditure in dental health care was defined as catastrophic if it was equal to or higher than 40% of the household capacity to pay. A number of individual and country-level factors were assessed as potential determinants of catastrophic dental health expenditure (CDHE) in multilevel logistic regression with individuals nested within countries. Up to 7% of households in low and middle income countries faced CDHE in the last 4 weeks. This proportion rose up to 35% among households that incurred some dental health expenditure within the same period. The multilevel model showed that wealthier, urban and larger households and more economically developed countries had higher odds of facing CDHE. The results of this study show that payments for dental health care can be a considerable burden on households, to the extent of preventing expenditure on basic necessities. They also help characterize households more likely to incur catastrophic expenditure on dental health care. Alternative health care financing strategies and policies targeted to improve fairness in financial contribution are urgently required in low and middle income countries.

The Clustering Effects of Surfaces within the Tooth and Teeth within Individuals

The objectives of this study were 1) to provide an estimate of the value of the intraclass correlation coefficient (ICC) for dental caries data at tooth and surface level, 2) to provide an estimate of the design effect (DE) to be used in the determination of sample size estimates for future dental surveys, and 3) to explore the usefulness of multilevel modeling of cross-sectional survey data by comparing the model estimates derived from multilevel and single-level models. Using data from the United Kingdom Adult Dental Health Survey 2009, the ICC and DE were calculated for surfaces within a tooth, teeth within the individual, and surfaces within the individual. Simple and multilevel logistic regression analysis was performed with the outcome variables carious tooth or surface. ICC estimated that 10% of the variance in surface caries is attributable to the individual level and 30% of the variance in surfaces caries is attributable to variation between teeth within individuals. When comparing multilevel with simple logistic models, β values were 4 to 5 times lower and the standard error 2 to 3 times lower in multilevel models. All the fit indices showed multilevel models were a better fit than simple models. The DE was 1.4 for the clustering of carious surfaces within teeth, 6.0 for carious teeth within an individual, and 38.0 for carious surfaces within the individual. The ICC for dental caries data was 0.21 (95% confidence interval [CI], 0.204–0.220) at the tooth level and 0.30 (95% CI, 0.284–0.305) at the surface level. The DE used for sample size calculation for future dental surveys will vary on the level of clustering, which is important in the analysis—the DE is greatest when exploring the clustering of surfaces within individuals. Failure to consider the effect of clustering on the design and analysis of epidemiological trials leads to an overestimation of the impact of interventions and the importance of risk factors in predicting caries outcome.

Longitudinal Study of Dental Caries Increment in Malaysian School Children: A 5-Year Cohort Study

The aim of this 5-year longitudinal cohort study was to assess the prevalence, severity, and trends in caries increment and impact of the School Dental Incremental Care Programme (SDICP). Data were gathered from school dental records as part of the SDICP. A sample of 1830 children were included and checked for caries experience annually using World Health Organization criteria. In total, 95.4% of the children were caries free in 2004, and caries experience declined to 70.5% in 2009 with an average of 4.9% annually. At baseline, the mean DMFT (confidence interval [CI]) was 0.06 (0.05-0.08) and increased to 0.58 (0.53-0.63) in 2009. Children with active caries were 4.4% in 2004, and figures rose to 9.6% in 2009. The FT component increased most rapidly during these 5 years from 0.2% to 25.1%. Overall caries prevalence and increment was low in this study. Proportions of FT component were higher as compared with DT component with low rate of extractions during the latter years of the study.

The relationship between oral health and oral health related quality of life among elderly people in United Kingdom

OBJECTIVES To identify the determinants of OHRQoL among older people in the United Kingdom. METHODS A subset of elderly (≥65year) participants from the UK Adult Dental Health Survey 2009 data was used. OHRQoL was assessed by means of the OHIP-14 additive score. The number of missing teeth; presence of active caries, dental pain, root caries, tooth wear, periodontal pockets>4mm, loss of attachment>9mm; having PUFA>0 (presence of severely decayed teeth with visible pulpal involvement, ulceration caused by dislocated tooth fragments, fistula and abscess); and wearing a denture were used as predictor variables. Age, gender, marital status, education level, occupation and presence of any long standing illness were used as control variables. Multivariate zero-inflated Poisson regression analysis was performed using R-project statistical software. RESULTS A total of 1277 elderly participants were included. The weighted mean(SE) OHIP-14 score of these participants was 2.95 (0.17). Having active caries (IRR=1.37, CI=1.25;1.50), PUFA>0 (IRR=1.17, CI=1.05;1.31), dental pain (IRR=1.34, CI=1.20;1.50), and wearing dentures (IRR=1.30, CI=1.17;1.44), were significantly positively associated with OHIP-14 score. Having periodontal pockets>4mm, at least one bleeding site, and anterior tooth wear were not significantly associated with the OHIP-14 score. CONCLUSION Whereas previous research has suggested a moderate relationship between oral disease and quality of life in this large scale survey of older adults, the presence of active caries and the presence of one or more of the PUFA indicators are associated with impaired oral health related quality of life in older adults, but not indicators of periodontal status. The implication of this is that whilst focussing on prevention of disease, there is an ongoing need for oral health screening and treatment in this group.