Improving the Quality of Dentistry (IQuaD): a cluster factorial randomised controlled trial comparing the effectiveness and cost-benefit of oral hygiene advice and/or periodontal instrumentation with routine care for the prevention and management of periodontal disease in dentate adults attending dental primary care

Scoping review of fidelity strategies used in behaviour change trials delivered in primary dental care settings

BACKGROUND

Primary dental care settings are strategically important locations where randomised controlled trials (RCTs) of behaviour change interventions (BCIs) can be tested to tackle oral diseases. Findings have so far produced equivocal results. Improving treatment fidelity is posed as a mechanism to improve scientific rigour, consistency and implementation of BCIs. The National Institutes of Health Behaviour Change Consortium (NIH BCC) developed a tool to assess and evaluate treatment fidelity in health behaviour change interventions, which has yet to be applied to the primary dental care BCI literature.

METHOD

We conducted a scoping review of RCTs delivered in primary dental care by dental team members (in real-world settings) between 1980 and 2023. Eligible studies were coded using the NIH BCC checklist to determine the presence of reported fidelity strategies across domains: design, training, delivery, receipt and enactment.

RESULTS

We included 34 eligible articles, reporting 21 RCTs. Fidelity reporting variations were found both between and within NIH BCC domains: strategy reporting ranged from 9.5 to 85.7% in design, 9.5 to 57.1% in training, 0 to 66.7% in delivery, 14.3 to 36.8% in receipt and 13.3 to 33.3% in enactment. The most reported domain was design (M = 0.45), and the least reported domain was delivery (M = 0.21). Only one study reported over 50% of the recommended strategies in every domain.

CONCLUSIONS

This review revealed inconsistencies in fidelity reporting with no evidence that fidelity guidelines or frameworks were being used within primary dental care trials. This has highlighted issues with interpretability, reliability and reproducibility of research findings. Recommendations are proposed to assist primary dental care trialists with embedding fidelity strategies into future research.

Effects of Systematic Oral Hygiene Guidance on Plaque Control Among Periodontal Patients

OBJECTIVE

To evaluate the efficacy of systematic oral hygiene instruction in improving oral hygiene knowledge and to practice and control oral plaque, among periodontal patients.

METHODS

A total of 407 patients were recruited, with 205 in the experimental group and 202 in the control group. Participants in the experimental group received professional dental examination, cleaning tools and instruction of oral hygiene practices. The patients in the control group received conventional educational guidance. Two follow-ups with 7-10-day intervals were conducted after the baseline examination.

RESULTS

Compared to those in control group, the plaque index of participants in the experimental group was significantly improved after the intervention. Moreover, participants' behaviours, including brushing twice or more a day, brushing more than 2 min, skill in using dental floss and brushing before going to bed, significantly improved after receiving professional systematic oral hygiene guidance (p < 0.001). Significant improvement was achieved in patients' oral hygiene knowledge, attitudes and practices (p < 0.001). Overall, 26.8% of the participants reached standard oral plaque control (plaque index ≤ 20%) in experimental group. Multivariable analysis showed that participants' old age and severity of illness had significant effects on plaque control.

CONCLUSION

Professional educational guidance is effective in maintaining good oral hygiene practices following periodontal management compare with conventional education. Oral health promotion interventions should be adjusted by age, severity of disease and the distal portion of the oral cavity.

Theoretically-informed vs standard cover letter to improve participant response to mailed questionnaire: results of an embedded randomised retention trial

BACKGROUND

Participant non-response is a source of bias in all research, especially in randomised controlled trials. Participants followed up remotely can have high non-response rates. Four such trials have been conducted of a cover letter with content informed by behaviour change theory to overcome hypothesised barriers to responding to a mailed questionnaire. Pooled results to date have suggested further research to be worthwhile. We conducted an embedded randomised study within a trial of such cover letters in the hope that we would improve response rates to our postal quality of life questionnaires.

METHODS

One hundred forty-eight participants in the CODIFI2 diabetic foot ulcer sampling trial were randomised 1:1 to receive one of two different cover letters at follow-up timepoints: either a standard cover letter accompanying their postal follow-up questionnaires or to an 'enhanced' (theory-informed) cover letter. Questionnaires were mailed at 39, 52 and (for some participants) 104 weeks post randomisation. Outcome measures were response to mailing at each timepoint. Analysis was restricted to those for whom a questionnaire and letter was issued. Owing to limited recruitment, a reduced analysis plan, comprising solely observed response rates and 95% confidence intervals for difference in response rates was followed. Post hoc, we added our week 52 results to an already-published meta-analysis.

RESULTS

Sixty-seven out of 74 enhanced cover letter group (Enhanced) and 67/74 standard cover letter group (Standard) participants who had not already died or withdrawn were sent their first mailing at 39 weeks. The 39-week response rates were 47/67 (70.1%) and 39/67 (58.2%) for Enhanced and Standard participants, respectively. At week 52, the response rates were 45/64 (70.3%) and 35/63 (55.6%) for Enhanced and Standard participants, respectively. At week 104, the response rates were 24/33 (72.7%) and 19/33 (57.6%) for the Enhanced and Standard participants, respectively. Adding our week 52 results to a published meta-analysis increased the pooled estimate of differences in response rates to 0.04 (- 0.01 to 0.09) favouring enhanced letters.

CONCLUSION

While this embedded randomised controlled trial observed greater response rates at all times among those randomised to the enhanced letter, the reduced sample size meant that these results are imprecise.

TRIAL REGISTRATION

ISRCTN registry ISRCTN74929588. Registered on 5 March 2019.

Benefits of Dental Scaling and Polishing in Adults: A Rapid Review and Evidence Synthesis

BACKGROUND

This rapid review assessed evidence to inform policy on the clinical effectiveness and optimal frequency of dental scaling and polishing (S&P) for adults, including those with low incomes eligible for the Canadian Dental Care Plan.

METHODS

A rapid review was conducted according to Cochrane Recommendations for Rapid Reviews. Populations included all adults, adults with periodontitis, and those with inequitable access to dental care. Primary outcomes included gingival inflammation, probing depths, and tooth loss. Secondary outcomes included oral health-related quality of life and economic impact. Four databases were searched for randomized clinical trials, systematic reviews, cohort studies, and practice guidelines. Risk of bias was evaluated using Cochrane Risk of Bias, Newcastle-Ottawa, ROBIS, and AGREE II tools. A qualitative synthesis was planned.

RESULTS

In total, 3,181 references were retrieved: 4 applied to "all adults" and 4 to those with periodontitis. All reports had low risk of bias. One systematic review and one multicenter trial of adults with regular dental care found no clinical benefit regardless of S&P interval; however, patients valued and were willing to pay for regular scaling. One claims-based study reported regular S&P reduced tooth loss, and 2 clinical practice guidelines found a reduced risk of future attachment and tooth loss, lower overall health care costs for diabetes, and reduced costs for and incidence of acute myocardial infarction in those with regular S&P. There were no studies of underserved populations.

CONCLUSIONS

For adults with no or early periodontal disease and regular access to dental care, routine S&P may have little clinical benefit but reduces tooth loss and some health care expenses. In patients with periodontitis, scaling intervals tailored to individual risk profile and periodontal status can maintain health. There is no evidence on the impact of routine S&P on patients with barriers accessing care.

KNOWLEDGE TRANSFER STATEMENT

In terms of the benefits of routine scaling and polishing in adults, this rapid review found mixed evidence with a high level of certainty due to minimal risk of bias in the appraised studies for "regular dental attenders" and those with a diagnosis of periodontal diseases. Tailored intervals for dental scaling are beneficial for those diagnosed with periodontitis but may not provide the clinical benefits previously expected for adults at low risk. There is no evidence that dental polishing is effective. No evidence was found to support recommendations about the clinical effectiveness of scaling or the most appropriate recall intervals for scaling for low-income Canadians eligible for dental services under the new Canadian Dental Care Plan.

Impact of public health and patient-centered prevention strategies on periodontitis and caries as causes of tooth loss in high-income countries

In high-income countries, the oral health of the population is influenced by public health interventions, widespread use of oral care products, dental practice measures, and the cost of dental treatment. We compiled information on changes of the prevalence of proximal and upstream determinants of periodontitis, caries, and tooth loss over the last three decades to outline their potential effects on changes of oral health during this period. Information was retrieved from repeated cross-sectional studies and from published literature. While both the prevalence of edentulism and the number of missing teeth (from the DMF-T index) decreased, the number of sound teeth as well as the total number of teeth increased. The prevalence of severe periodontitis was unchanged, whereas the prevalence of periodontal health and moderate periodontitis may have increased to a minor extent. Concerning oral health risk factors, the proportion of individuals with tertiary education increased, while smoking prevalence declined. More and more people used oral care products. Whether one reimbursement system worked better than another one in terms of tooth retention could not be elucidated. In tooth retention, population-wide use of fluoridated toothpastes had the greatest impact. To some extent, the higher number of teeth present may be related to the more frequent use of interdental cleaning aids and powered toothbrushes. Since there was no decrease in severe periodontitis in most cohorts, periodontal interventions probably contributed little to improved tooth retention.

Stability of Willingness to Pay: Does Time and Treatment Allocation in a Randomized Controlled Trial Influence Willingness to Pay?

BACKGROUND

Willingness-to-pay (WTP) estimates are useful to policy makers only if they are generalizable beyond the moment when they are collected. To understand the "shelf life" of preference estimates, preference stability needs be tested over substantial periods of time.

METHODS

We tested the stability of WTP for preventative dental care (scale and polish) using a payment-card contingent valuation question administered to 909 randomized controlled trial participants at 4 time points: baseline (prerandomization) and at annual intervals for 3 years. Trial participants were regular attenders at National Health Service dental practices. Participants were randomly offered different frequencies (intensities) of scale polish (no scale and polish, 1 scale and polish per year, 2 scale and polishes per year). We also examined whether treatment allocation to these different treatment intensities influenced the stability of WTP. Interval regression methods were used to test for changes in WTP over time while controlling for changes in 2 determinants of WTP. Individual-level changes were also examined as well as the WTP function over time.

RESULTS

We found that at the aggregate level, mean WTP values were stable over time. The results were similar by trial arm. Individuals allocated to the arm with the highest scale and polish intensity (2 per year) had a slight increase in WTP toward the latter part of the trial. There was considerable variation at the individual level. The WTP function was stable over time.

CONCLUSIONS

The payment-card contingent valuation method can produce stable WTP values in health over time. Future research should explore the generalizability of these results in other populations, for less familiar health care services, and using alternative elicitation methods.

HIGHLIGHTS

Stated preferences are commonly used to value health care.Willingness-to-pay (WTP) estimates are useful only if they have a "shelf life."Little is known about the stability of WTP for health care.We test the stability of WTP for dental care over 3 y.Our results show that the contingent valuation method can produce stable WTP values.

The economic and societal impact of periodontal and peri-implant diseases

Periodontal and peri-implant diseases result from a chronic inflammatory response to dysbiotic microbial communities and are characterized by inflammation in the soft tissue and the ensuing progressive destruction of supporting bone, resulting in tooth or implant loss. These diseases' high prevalence, multifactorial etiology, extensive treatment costs, and significant detriment to patients' quality-of-life underscore their status as a critical public health burden. This review delineates the economic and sociocultural ramifications of periodontal and peri-implant diseases on patient welfare and healthcare economics. We delve into the implications of diagnosis, treatment, supportive care, and managing destructive tissue consequences, contrasting these aspects with healthy patients.

Justification for the 2017 periodontitis classification in the light of the Checklist for Modifying Disease Definitions: A narrative review

Once a while, disease classifications have needed revision because new knowledge has accumulated, and new technologies and better treatments have emerged. Changes made to disease classifications should be trustworthy and openly justified. The periodontitis definition and classification system was changed in 2017 by the 'World Workshop on the Classification of Periodontal and Peri-Implant Diseases and Conditions'. The workshop, comprising clinicians and researchers, resulted in the production of a 23-article special issue that introduced the new definitions and classifications of periodontitis. In this narrative review, we critically review how the changes made to the periodontitis definition and classification were justified in the light of the Checklist for Modifying Disease Definitions. Under each of the eight items of the checklist, we have discussed how the item was or could have been considered in the light of the checklist and its guidance. In our view, the new definition and classification of periodontitis was presented in an understandable way, even though the changes from the previous definition were not made visible. However, the issues of (1) estimated changes in prevalence or incidence, (2) triggers for the change, (3) prognostic ability, (4) repeatability or reproducibility, (5) incremental benefits, (6) incremental harms or (7) net benefits and harms related to the introduction of new classification were not considered in the way suggested in the checklist. Thereby, a balanced assessment of potential benefits and harms associated with the new periodontitis classification system was not presented, and to a large extent it remains unknown if the use of the new classification system will provide more net benefits to patients and to the community than previous systems. It is our view that patients and societies deserve transparent and balanced assessments of the potential benefits and harms associated with the periodontitis classification. Importantly, these should reflect the values and preferences also of the patients and the wider community and consider the impact on resource usage.

Effects of universal oral healthcare coverage in an adult population: A long-term nationwide natural experiment

OBJECTIVES

A large and long-term natural experiment occurred in Finland from the late 1980s-2000, when adults' entitlement to subsidized oral healthcare was strongly dependent on the arbitrary classification based on their year of birth: people born in 1956 or later were entitled to subsidized care, while people born before 1956 were not. The aim of this study was to investigate the effect of this expanded universal oral healthcare coverage on service use and oral health outcomes.

METHODS

Data from annual nationally representative cross-sectional postal surveys among 15-64-year-olds between 1990 and 2014 were used. For this study, the following outcome variables were formed: experiencing toothache during the past month (yes/no), the number of missing teeth with three different thresholds (over 10, over 5 or at least 1 missing tooth), brushing more than once a day and the number of visits to the dentist. Regression discontinuity plots and bias-corrected local polynomial regression discontinuity estimators measuring the effect of the extended universal coverage on the outcomes at the year-of-birth cut-off of 1956 were generated separately from the data from 1990 to 2000 and from 2002 to 2014.

RESULTS

Between 1990 and 2000, the number of visits to the dentist (0.2 visits, 95% CI, confidence intervals: -0.03; 0.43) and the proportion of those who visited the dentist during the past 12 months (4.2%, 95% CI: 0.1%; 8.3%) increased at the year-of-birth cut-off of 1956. There were minor drops (1.5%-1.9%) in the number of missing teeth across all thresholds (over 10, over 5, or at least 1 missing teeth) at the cut-off. Analyses with the data from the surveys from 2002 to 2014 showed that there were no discontinuities in these outcomes at the cut-off of 1956. Regression discontinuity estimates related to toothache experience and toothbrushing frequency were inconclusive due to high variability in the underlying data and the likely small effect of the more universal coverage on these outcomes.

CONCLUSIONS

The current study provided evidence of the beneficial effects of universal oral healthcare coverage on the oral healthcare service use and teeth preservation from a large and long-term natural experiment occurred in Finland from the late 1980s to 2000.

Behavioral Interventions on Periodontitis Patients to Improve Oral Hygiene: A Systematic Review

This systematic review aimed to investigate the impact of different psychological models, strategies, and methods to improve plaque control and/or gingival inflammation in patients with periodontal diseases. Methods: The PubMed/MEDLINE, Cochrane Library, and Embase online databases were explored to identify relevant studies published before October 2022. Articles investigating the effects of different psychological approaches and intervention strategies on periodontitis patients’ oral hygiene (OH) behavioral change were screened. Results: 5460 articles were identified, and 21 fulfilled the inclusion criteria. In total, 2 studies tested audio-visual modalities, and the remaining 19 publications involved six psychological models of health-related behavioral interventions, including Social Cognitive Theory, the Theory of Planned Behavior, the Health Action Process Approach, Leventhal’s self-regulatory theory, Motivational Interviewing, and Cognitive Behavioral Therapy. A meta-analysis of the results was not carried out due to the high heterogeneity among the interventions. Conclusions: Considering the limitations of the available studies, psychological interventions based on social cognitive models that combine some of the techniques of this model (goal setting, planning, self-monitoring, and feedback) may improve OH in periodontitis patients, having a positive impact on periodontal clinical outcomes. Delivering cognitive behavioral therapy in combination with motivational interviewing may result in an improvement in OH as evaluated by decreasing plaque and bleeding scores.

Economic Evaluations of Preventive Interventions for Dental Caries and Periodontitis: A Systematic Review

OBJECTIVES

To critically examine the methods used for full economic evaluations of preventive interventions for dental caries and periodontitis.

METHODS

Published literature post-2000 was searched to April 2021. Based on a developed intervention classification framework for dental caries and periodontitis, only universal, selective or indicated interventions were included in this review. The Drummond 10-point checklist was used for quality appraisal.

RESULTS

Of 3,007 unique records screened for relevance, 73 studies were reviewed. Most model-based studies (61/73) used cost-effectiveness analysis (49%) or cost-benefit analysis (28%). Trial-based studies (16/73) commonly used cost-effectiveness analysis (59%). Four studies used both economic evaluation methods. Sixty-four papers (88%) were on dental caries, eight papers (11%) focused on periodontitis, and one paper (1%) included both oral diseases; 72% of model-based and 82% of trial-based studies were of good quality. The most frequently investigated dental caries preventive interventions were water fluoridation (universal intervention; cost-saving or cost-effective), fissure sealant and fluoride varnish (selective and indicated interventions; cost-effectiveness outcomes were inconsistent). Supportive periodontal therapy with oral health education (indicated intervention; cost-effective) was the most frequently evaluated preventive intervention for periodontitis. Thirty percent of studies with a time horizon > 1 year did not apply an appropriate discount rate and 26% did not comprehensively discuss other important considerations beyond the technical analysis.

CONCLUSIONS

Generic health outcome measures should be incorporated for economic evaluations on preventive interventions for dental caries and periodontitis, and an increased focus to prevent periodontitis using economic evaluation methods is needed to inform resource allocation and policy decision-making.

Does in vitro fertilization (IVF) treatment provide good value for money? A cost-benefit analysis

Background

Using traditional health technology assessment (HTA) outcome metrics, such as quality-adjusted life-years, to assess fertility treatments raises considerable methodological challenges because the objective of fertility treatments is to create new life rather than extend, save, or improve health-related quality of life.

Objective

The aim of this study was to develop a novel cost-benefit framework to assess value for money of publicly funded IVF treatment; to determine the number of cost-beneficial treatment cycles for women of different ages; and to perform an incremental cost-benefit analysis from a taxpayer perspective.

Methods

We developed a Markov model to determine the net monetary benefit (NMB) of IVF treatment by female age and number of cycles performed. IVF treatment outcomes were monetized using taxpayers' willingness-to-pay values derived from a discrete choice experiment (DCE). Using the current funding environment as the comparator, we performed an incremental analysis of only funding cost-beneficial cycles. Similar outputs to cost-effectiveness analyses were generated, including net-benefit acceptability curves and cost-benefit planes. We created an interactive online app to provide a detailed and transparent presentation of the results.

Results

The results suggest that at least five publicly funded IVF cycles are cost-beneficial in women aged <42 years. Cost-benefit planes suggest a strong taxpayer preference for restricting funding to cost-beneficial cycles over current funding arrangements in Australia from an economic perspective.

Conclusions

The provision of fertility treatment is valued highly by taxpayers. This novel cost-benefit method overcomes several challenges of conventional cost-effectiveness methods and provides an exemplar for incorporating DCE results into HTA. The results offer new evidence to inform discussions about treatment funding arrangements.

Current practice in the measurement and interpretation of intervention adherence in randomised controlled trials: A systematic review

BACKGROUND

Ideally all participants in a randomised controlled trial (RCT) should fully receive their allocated intervention; however, this rarely occurs in practice. Intervention adherence affects Type II error so influences the interpretation of trial results and subsequent implementation. We aimed to describe current practice in the definition, measurement, and reporting of intervention adherence in non-pharmacological RCTs, and how this data is incorporated into a trial's interpretation and conclusions.

METHODS

We conducted a systematic review of phase III RCTs published between January 2018 and June 2020 in the National Institute for Health Research Journals Library for the Health Technology Assessment, Programme Grants for Applied Research, and Public Health Research funding streams.

RESULTS

Of 237 reports published, 76 met the eligibility criteria and were included. Most RCTs (n = 68, 89.5%) reported adherence, though use of terminology varied widely; nearly three quarters of these (n = 49, 72.1%) conducted a sensitivity analysis. Adherence measures varied between intervention types: behavioural change (n = 10, 43.5%), psychological therapy (n = 5, 83.3%) and physiotherapy/rehabilitation (n = 8, 66.7%) interventions predominately measured adherence based on session attendance. Whereas medical device and surgical interventions (n = 17, 73.9%) primarily record the number of participants receiving the allocated intervention, a third (n = 33, 67.3%) of studies reported a difference in findings between primary and sensitivity analyses.

CONCLUSIONS

Although most trials report elements of adherence, terminology was inconsistent, and there was no systematic approach to its measurement, analyses, interpretation, or reporting. Given the importance of adherence within clinical trials, there is a pressing need for a standardised approach or framework.

Statistical analysis of publicly funded cluster randomised controlled trials: a review of the National Institute for Health Research Journals Library

BACKGROUND

In cluster randomised controlled trials (cRCTs), groups of individuals (rather than individuals) are randomised to minimise the risk of contamination and/or efficiently use limited resources or solve logistic and administrative problems. A major concern in the primary analysis of cRCT is the use of appropriate statistical methods to account for correlation among outcomes from a particular group/cluster. This review aimed to investigate the statistical methods used in practice for analysing the primary outcomes in publicly funded cluster randomised controlled trials, adherence to the CONSORT (Consolidated Standards of Reporting Trials) reporting guidelines for cRCTs and the recruitment abilities of the cluster trials design.

METHODS

We manually searched the United Kingdom's National Institute for Health Research (NIHR) online Journals Library, from 1 January 1997 to 15 July 2021 chronologically for reports of cRCTs. Information on the statistical methods used in the primary analyses was extracted. One reviewer conducted the search and extraction while the two other independent reviewers supervised and validated 25% of the total trials reviewed.

RESULTS

A total of 1942 reports, published online in the NIHR Journals Library were screened for eligibility, 118 reports of cRCTs met the initial inclusion criteria, of these 79 reports containing the results of 86 trials with 100 primary outcomes analysed were finally included. Two primary outcomes were analysed at the cluster-level using a generalized linear model. At the individual-level, the generalized linear mixed model was the most used statistical method (80%, 80/100), followed by regression with robust standard errors (7%) then generalized estimating equations (6%). Ninety-five percent (95/100) of the primary outcomes in the trials were analysed with appropriate statistical methods that accounted for clustering while 5% were not. The mean observed intracluster correlation coefficient (ICC) was 0.06 (SD, 0.12; range, - 0.02 to 0.63), and the median value was 0.02 (IQR, 0.001-0.060), although 42% of the observed ICCs for the analysed primary outcomes were not reported.

CONCLUSIONS

In practice, most of the publicly funded cluster trials adjusted for clustering using appropriate statistical method(s), with most of the primary analyses done at the individual level using generalized linear mixed models. However, the inadequate analysis and poor reporting of cluster trials published in the UK is still happening in recent times, despite the availability of the CONSORT reporting guidelines for cluster trials published over a decade ago.

UK general population willingness to pay for scale and polish, and detailed and personalized oral hygiene advice

OBJECTIVES

Understanding the value the general population place on dentistry services is important for policymakers to aide service planning. Willingness to pay (WTP) is an economic method used to elicit the value of a good or service. The aim of this study is to estimate United Kingdom (UK) general population WTP for commonly provided scale and polish, and detailed and personalized oral hygiene advice (OHA), and to investigate what factors influence WTP.

METHODS

Participants completed an online hypothetical WTP survey for scale and polish and detailed and personalized oral hygiene advice. The estimation sample consisted of 1405 participants, nationally representative of the UK general population in terms of age and sex. Regression analysis was used to estimate WTP and determine what factors are associated with WTP. Analyses were conducted including and excluding protest answers.

RESULTS

The mean (SD) WTP for a scale and polish is £26.77 (£21.91) excluding protest answers and £24.80 (£22.71) for the full sample. The mean (SD) WTP for detailed and personalized OHA is £16.56 (£19.75) excluding protest answers and £12.77 (£22.28) for the full sample. Participants on higher incomes, private attenders and those who stated that maintaining clean and healthy gums was important had higher WTP for both services. Participants in Scotland and Northern Ireland were WTP less than their English counterparts, reflecting the different regional specific payment systems.

CONCLUSION

The general UK population value scale and polish, and detailed and personalized OHA. This study provides estimates of WTP for these services which can be used to inform resource allocation decisions.

Have you had bleeding from your gums? Self-report to identify giNGival inflammation (The SING diagnostic accuracy and diagnostic model development study)

AIM

To assess the diagnostic performance of self-reported oral health questions and develop a diagnostic model with additional risk factors to predict clinical gingival inflammation in systemically healthy adults in the United Kingdom.

METHODS

Gingival inflammation was measured by trained staff and defined as bleeding on probing (present if bleeding sites ≥ 30%). Sensitivity and specificity of self-reported questions were calculated; a diagnostic model to predict gingival inflammation was developed and its performance (calibration and discrimination) assessed.

RESULTS

We included 2853 participants. Self-reported questions about bleeding gums had the best performance: the highest sensitivity was 0.73 (95% CI 0.70, 0.75) for a Likert item and the highest specificity 0.89 (95% CI 0.87, 0.90) for a binary question. The final diagnostic model included self-reported bleeding, oral health behaviour, smoking status, previous scale and polish received. Its area under the curve was 0.65 (95% CI 0.63-0.67).

CONCLUSION

This is the largest assessment of diagnostic performance of self-reported oral health questions and the first diagnostic model developed to diagnose gingival inflammation. A self-reported bleeding question or our model could be used to rule in gingival inflammation since they showed good sensitivity, but are limited in identifying healthy individuals and should be externally validated.

Economic evaluations in the treatment and evaluation of patients with periodontal disease: A critical review

AIM

To evaluate the types and quality of reporting of economic evaluations carried out in the clinical management of periodontal disease over 32 years from 1987 to 2019.

MATERIAL AND METHODS

A systematic search of articles from 1987 to 2019 was conducted using PubMed, Web of Science, The Cochrane Central Register of Controlled Trials, Health Technology Assessment Database and Embase. The quality of the economic evaluations was assessed based on the Consolidated Health Economic Evaluation Reporting Standard checklist. Due to considerable between-study heterogeneity, a meta-analysis was not performed.

RESULTS

Twenty one publications were included. 11 studies used cost-effectiveness analysis, five used cost-minimization analysis, four used cost-utility analysis and two used cost-benefit analysis. Comparators, choice of health outcomes, estimating resources and costs were fully reported in all studies. Many studies had inadequate reporting in terms of estimating resources and costs, choice of health outcomes, characterizing heterogeneity and study perspective.

CONCLUSIONS

There has been an increase in health economics studies in the field of clinical periodontology over the past decade. Several studies did not report study perspective, and the health outcomes chosen were not relevant for some studies. Future studies should follow an economic evaluation checklist for high-quality reporting and consistency.

Promoting behavioural changes to improve oral hygiene in patients with periodontal diseases: A systematic review

AIM

This systematic review investigates the impact of specific interventions aiming at promoting behavioural changes to improve oral hygiene (OH) in patients with periodontal diseases.

METHODS

A literature search was performed on different databases up to March 2019. Randomized and non-randomized controlled trials evaluating the effects of behavioural interventions on plaque and bleeding scores in patients with gingivitis or periodontitis were considered. Pooled data analysis was conducted by estimating standardized mean difference between groups.

RESULTS

Of 288 articles screened, 14 were included as follows: 4 studies evaluated the effect of motivational interviewing (MI) associated with OH instructions, 7 the impact of oral health educational programmes based on cognitive behavioural therapies, and 3 the use of self-inspections/videotapes. Studies were heterogeneous and reported contrasting results. Meta-analyses for psychological interventions showed no significant group difference for both plaque and bleeding scores. No effect was observed in studies applying self-inspection/videotapes.

CONCLUSIONS

Within the limitations of the current evidence, OH may be reinforced in patients with periodontal diseases by psychological interventions based on cognitive constructs and MI principles provided by oral health professionals. However, no conclusion can be drawn on their specific clinical efficacy as measured by reduction of plaque and bleeding scores over time.

Study design and primary outcome in randomized controlled trials in periodontology. A systematic review

AIM

The aim of this review is to assess study design and risk of bias related to primary outcome in recently published randomized controlled trials (RCTs) in periodontology.

METHOD

An electronic (Medline, EMBASE and Cochrane library) and a manual search were completed to detect RCTs in humans, with an outcome in the field of periodontology and published in English from January 2018 up to March 2020.

RESULTS

Data extraction of 318 publications meeting the inclusion criteria was performed by two reviewers. Most studies adopted a parallel-group superiority design in a university setting. Overall, 54% of papers reported the primary outcome and relative sample size calculation, while only 37% also included reproducibility estimates relative to the primary outcome. Papers published in journals with higher impact factors had better compliance with primary outcome reporting and lower overall risk of bias scores.

CONCLUSION

Improvements in the quality of RCTs in periodontology are still needed. The importance of defining a clinically relevant study primary outcome and building the study around it needs to be emphasized. Furthermore, RCTs in periodontology could consider, when appropriate, some of the study design options which facilitate application of the principles of personalized medicine.

Examining the impact of oral hygiene advice and/or scale and polish on periodontal disease: the IQuaD cluster factorial randomised controlled trial

Objective To compare the clinical effectiveness and cost benefit of different frequencies of scale and polish (S&P) treatments in combination with different types of oral hygiene advice (OHA).

Design Multi-centre, multi-level cluster randomised factorial open trial with blinded outcome evaluation. UK dental practices were cluster randomised to deliver OHA as usual or personalised. In a separate randomisation, patients were allocated to receive S&P 6-monthly, 12-monthly or never.

Setting UK primary dental care.

Participants Practices providing NHS care and adults who had received regular dental check-ups.

Main outcome measures The percent of sites with bleeding on probing, patient confidence in self-care, incremental net benefits (INB) over three years.

Results Sixty-three practices and 1,877 adult patients were randomised and 1,327 analysed (clinical outcome). There was no statistically significant or clinically important difference in gingival bleeding between the three S&P groups (for example, six-monthly versus none: difference 0.87% sites, 95% CI: 1.6 to 3.3, p = 0.48) or between personalised or usual OHA groups (difference -2.5% sites, -95%CI: -8.3 to 3.3, p = 0.39), or oral hygiene self-efficacy (cognitive impact) between either group (for example, six-monthly versus none: difference -0.028, 95% CI -0.119 to 0.063, p = 0.543). The general population place a high value on, and are willing to pay for, S&P services. However, from a dental health perspective, none of the interventions were cost-effective.

Conclusion Results suggest S&P treatments and delivering brief personalised OHA provide no clinical benefit and are therefore an inefficient approach to improving dental health (38% of sites were bleeding whatever intervention was received). However, the general population value both interventions.

Describes the process of successfully delivering a multi-centre, cluster randomised factorial open trial in general dental practice in the NHS, for the most frequently provided dental treatment, scale and polish (S&P), and oral hygiene advice.

Highlights the clinical, economic and patient-centred outcomes from providing S&P at different time intervals alongside personalised or routine oral hygiene advice to over 2,000 participants for three years.

Evidence from IQuaD concludes that there was no difference in gingival bleeding across trial arms at three years; however, the general population are willing to pay for and place a high value on both S&P and personalised oral hygiene advice.

The Value of Preventative Dental Care: A Discrete-Choice Experiment

Scale and polish (SP) and oral hygiene advice (OHA) are commonly provided in primary care dental practice to help prevent periodontal disease. These services are widely consumed by service users, incurring substantial cost, without any clear evidence of clinical benefit. This article aims to elicit general population preferences and willingness to pay (WTP) for preventative dental care services and outcomes. An online discrete-choice experiment (DCE) was completed by a nationally representative sample of the UK general population. Respondents each answered 10 choice tasks that varied in terms of service attributes (SP, OHA, and provider of care), outcomes (bleeding gums and aesthetics), and cost. Choice tasks were selected using a pivoted segmented experimental design to improve task realism. An error components panel logit model was used to analyze the data. Marginal WTP (mWTP) for each attribute and level was calculated. In total, 667 respondents completed the DCE. Respondents valued more frequent SP, care provided by a dentist, and personalized OHA. Respondents were willing to pay for dental packages that generated less frequent ("never" or "hardly ever") bleeding on brushing and teeth that look and feel at least "moderately clean." Respondents were willing to pay more (+£145/y) for improvements in an aesthetic outcome from "very unclean" (-£85/y) to "very clean" (+£60/y) than they were for reduced bleeding frequency (+£100/y) from "very often" (-£54/y) to "never" (+£36/y). The general population value routinely provided SP, even in the absence of reductions in bleeding on brushing. Dental care service providers must consider service user preferences, including preferences for both health and nonhealth outcomes, as a key factor in any service redesign. Furthermore, the results provide mWTP estimates that can be used in cost-benefit analysis of these dental care services.

Dental therapists compared with general dental practitioners for undertaking check-ups in low-risk patients: pilot RCT with realist evaluation

Background

Many dental ‘check-ups’ in the NHS result in no further treatment. The patient is examined by a dentist and returned to the recall list for a further check-up, commonly in 6 or 12 months’ time. As the oral health of regular dental attenders continues to improve, it is likely that an increasing number of these patients will be low risk and will require only a simple check-up in the future, with no further treatment. This care could be delivered by dental therapists. In 2013, the body responsible for regulating the dental profession, the General Dental Council, ruled that dental therapists could see patients directly and undertake check-ups and routine dental treatments (e.g. fillings). Using dental therapists to undertake check-ups on low-risk patients could help free resources to meet the future challenges for NHS dentistry.

Objectives

The objectives were to determine the most appropriate design for a definitive study, the most appropriate primary outcome measure and recruitment and retention rates, and the non-inferiority margin. We also undertook a realist-informed process evaluation and rehearsed the health economic data collection tool and analysis.

Design

A pilot randomised controlled trial over a 15-month period, with a realist-informed process evaluation. In parallel, we rehearsed the health economic evaluation and explored patients’ preferences to inform a preference elicitation exercise for a definitive study.

Setting

The setting was NHS dental practices in North West England.

Participants

A total of 217 low-risk patients in eight high-street dental practices participated.

Interventions

The current practice of using dentists to provide NHS dental check-ups (treatment as usual; the control arm) was compared with using dental therapists to provide NHS dental check-ups (the intervention arm).

Main outcome measure

The main outcome measure was difference in the proportion of sites with bleeding on probing among low-risk patients. We also recorded the number of ‘cross-over’ referrals between dentists and dental therapists.

Results

No differences were found in the health status of patients over the 15 months of the pilot trial, suggesting that non-inferiority is the most appropriate design. However, bleeding on probing suffered from ‘floor effects’ among low-risk patients, and recruitment rates were moderately low (39.7%), which suggests that an experimental design might not be the most appropriate. The theory areas that emerged from the realist-informed process evaluation were contractual, regulatory, institutional logistics, patients’ experience and logistics. The economic evaluation was rehearsed and estimates of cost-effectiveness made; potential attributes and levels that can form the basis of preference elicitation work in a definitive study were determined.

Limitations

The pilot was conducted over a 15-month period only, and bleeding on probing appeared to have floor effects. The number of participating dental practices was a limitation and the recruitment rate was moderate.

Conclusions

Non-inferiority, floor effects and moderate recruitment rates suggest that a randomised controlled trial might not be the best evaluative design for a definitive study in this population. The process evaluation identified multiple barriers to the use of dental therapists in ‘high-street’ practices and added real value.

Future work

Quasi-experimental designs may offer more promise for a definitive study alongside further realist evaluation.

Trial registration

Current Controlled Trials ISRCTN70032696.

Funding

This project was funded by the National Institute for Health Research (NIHR) Health Services and Delivery Research programme and will be published in full in Health Services and Delivery Research; Vol. 9, No. 3. See the NIHR Journals Library website for further project information.

The Effect of a Personalized Oral Health Education Program on Periodontal Health in an At-Risk Population: A Randomized Controlled Trial

While periodontal disease is associated with many risk factors, socioeconomically disadvantaged communities experience the highest disease burden. The aim of this study was to evaluate the effectiveness of a personalized oral health education program, in combination with routine dental treatment, in participants from a low socioeconomic community. We used a randomized, controlled, examiner-blinded clinical trial. A total of 579 participants (aged 18–60 years) were randomly grouped: the intervention group (n = 292) received a personalized oral health education program in combination with routine dental care and the control group (n = 287) received routine dental care. All participants were assessed for improvement in oral health care behaviors, dental plaque, and periodontal status at baseline, 12 months, and 24 months. We found a significant drop (p < 0.001) in the plaque indices, Periodontal Probing Depths (PPD) and Bleeding on Probing (BOP) between baseline and the 12-month follow-up for both groups. For BOP, the number of sites positive was significantly different between baseline and the 24-month follow-up (p = 0.037). No differences were found between the two groups for any evaluated clinical outcome. The personalized oral health education program used in the current study did not appear to add significant improvement to clinical outcomes of periodontal health compared with routine restorative dental care per se.

An overview of the methodological aspects and policy implications of willingness-to-pay studies in oral health: a scoping review of existing literature

BACKGROUND

Demands for dental services seem to be beyond the capacities of most healthcare systems these days. Patient preferences have been increasingly emphasized to be considered in the joint decision-making process. Willingness-to-pay (WTP) is a recommended method for measuring the utility of health services; increasingly being used in recent decades. Taking these points into consideration, this article aims to provide an overview of the methodological aspects and policy implications of WTP studies in the field of oral health.

METHODS

The research was conducted in ISPOR, PubMed and Google Scholar databases. In addition, reference lists of included articles were checked to identify the relevant studies. All studies published were included that were in the English language and reported using WTP for oral health-related goods and services. A data-charting form was developed by a focus group discussion panel of seven experts to derive the main methodological aspects of WTP. Also, Core policy suggestions were categorized through thematic content analysis of the included papers.

RESULTS

The search strategy yielded 389 studies of which 52 were included. WTP studies in oral health show an increasing trend in global publications. The UK and Canada have a greater share in published material than in any other country. The dominant field of these researches is in restorative and prosthetic dentistry, and a wide range of different methodological aspects was documented. Policy suggestions were categorized in three main themes: (A) setting new tariffs or subsidizing the item, (B) provision of the item due to population preferences, and (C) improving literacy regarding the item.

CONCLUSIONS

An urgent need for a common framework regarding the design of WTP studies in dentistry seems paramount. Some policy suggestions seem not to be applicable, perhaps due to insufficient familiarity of the researchers with the complexities of the public policymaking process.

Risk-based, 6-monthly and 24-monthly dental check-ups for adults: the INTERVAL three-arm RCT

BACKGROUND

Traditionally, patients are encouraged to attend dental recall appointments at regular 6-month intervals, irrespective of their risk of developing dental disease. Stakeholders lack evidence of the relative effectiveness and cost-effectiveness of different recall strategies and the optimal recall interval for maintenance of oral health.

OBJECTIVES

To test effectiveness and assess the cost-benefit of different dental recall intervals over a 4-year period.

DESIGN

Multicentre, parallel-group, randomised controlled trial with blinded clinical outcome assessment at 4 years and a within-trial cost-benefit analysis. NHS and participant perspective costs were combined with benefits estimated from a general population discrete choice experiment. A two-stratum trial design was used, with participants randomised to the 24-month interval if the recruiting dentist considered them clinically suitable. Participants ineligible for 24-month recall were randomised to a risk-based or 6-month recall interval.

SETTING

UK primary care dental practices.

PARTICIPANTS

Adult, dentate, NHS patients who had visited their dentist in the previous 2 years.

INTERVENTIONS

Participants were randomised to attend for a dental check-up at one of three dental recall intervals: 6-month, risk-based or 24-month recall.

MAIN OUTCOMES

Clinical - gingival bleeding on probing; patient - oral health-related quality of life; economic - three analysis frameworks: (1) incremental cost per quality-adjusted life-year gained, (2) incremental net (societal) benefit and (3) incremental net (dental health) benefit.

RESULTS

A total of 2372 participants were recruited from 51 dental practices; 648 participants were eligible for the 24-month recall stratum and 1724 participants were ineligible. There was no evidence of a significant difference in the mean percentage of sites with gingival bleeding between intervention arms in any comparison. For the eligible for 24-month recall stratum: the 24-month (n = 138) versus 6-month group (n = 135) had an adjusted mean difference of -0.91 (95% confidence interval -5.02 to 3.20); the risk-based (n = 143) versus 6-month group had an adjusted mean difference of -0.98 (95% confidence interval -5.05 to 3.09); the 24-month versus risk-based group had an adjusted mean difference of 0.07 (95% confidence interval -3.99 to 4.12). For the overall sample, the risk-based (n = 749) versus 6-month (n = 737) adjusted mean difference was 0.78 (95% confidence interval -1.17 to 2.72). There was no evidence of a difference in oral health-related quality of life between intervention arms in any comparison. For the economic evaluation, under framework 1 (cost per quality-adjusted life-year) the results were highly uncertain, and it was not possible to identify the optimal recall strategy. Under framework 2 (net societal benefit), 6-month recalls were the most efficient strategy with a probability of positive net benefit ranging from 78% to 100% across the eligible and combined strata, with findings driven by the high value placed on more frequent recall services in the discrete choice experiment. Under framework 3 (net dental health benefit), 24-month recalls were the most likely strategy to deliver positive net (dental health) benefit among those eligible for 24-month recall, with a probability of positive net benefit ranging from 65% to 99%. For the combined group, the optimal strategy was less clear. Risk-based recalls were more likely to be the most efficient recall strategy in scenarios where the costing perspective was widened to include participant-incurred costs, and in the Scottish subgroup.

LIMITATIONS

Information regarding factors considered by dentists to inform the risk-based interval and the interaction with patients to determine risk and agree the interval were not collected.

CONCLUSIONS

Over a 4-year period, we found no evidence of a difference in oral health for participants allocated to a 6-month or a risk-based recall interval, nor between a 24-month, 6-month or risk-based recall interval for participants eligible for a 24-month recall. However, people greatly value and are willing to pay for frequent dental check-ups; therefore, the most efficient recall strategy depends on the scope of the cost and benefit valuation that decision-makers wish to consider.

FUTURE WORK

Assessment of the impact of risk assessment tools in informing risk-based interval decision-making and techniques for communicating a variable recall interval to patients.

TRIAL REGISTRATION

Current Controlled Trials ISRCTN95933794.

FUNDING

This project was funded by the National Institute for Health Research (NIHR) Health Technology Assessment programme [project numbers 06/35/05 (Phase I) and 06/35/99 (Phase II)] and will be published in full in Health Technology Assessment; Vol. 24, No. 60. See the NIHR Journals Library website for further project information.

Breaking the wave of peri-implantitis

Peri-implant diseases are prevalent with a weighted mean prevalence rate of 43% across Europe and 22% across South and North America. Although the main etiologic agent is bacterial biofilm, a myriad of factors influence the initiation and progression of the disease. Unfortunately, the treatment of peri-implant diseases is at best favorable in the short term with a high rate of persistent inflammation and recurrence. Therefore, it is sensible to consider and control all potential factors that may predispose an implant to peri-implant tissue inflammation in an attempt to avoid the disease. This paper reviews recent evidence on factors that may predispose implants to peri-implantitis and measures that can be taken to prevent it.

Three behavior change theory-informed randomized studies within a trial to improve response rates to trial postal questionnaires

OBJECTIVES

Our aim was to design and evaluate a novel behavior change approach to increase response rates to an annual postal questionnaire in three randomized studies within a trial (SWAT) and replicate the most promising SWAT.

STUDY DESIGN AND SETTING

SWAT1 tested a trial logo sticker on questionnaire envelopes vs. no sticker; SWAT2 tested a theoretically informed letter sent with the questionnaire vs. a standard letter; SWAT3 tested a theoretically informed newsletter sent before the questionnaire vs. no newsletter. The SWATs were conducted within a large dental trial (N = 1,877 adults), and SWAT2 replicated in a different trial in a similar setting (N = 2,372).

RESULTS

SWAT1 improved response rates by 1.4%, 95% confidence interval (CI) (-7.2%, 10.0%). SWAT2 improved response rates by 7.0%, 95% CI (1.7%, 12.3%). SWAT3 improved response rates by 0.8%, 95% CI (-5.1%, 6.7%). Replication of SWAT2 as the most promising SWAT showed improvement in response rates of 1.0%, 95% CI (-3.2%, 5.3%). Pooled results from SWAT2 showed an overall improvement in response rates of 3.4%, 95% CI (0.1%, 6.7%).

CONCLUSION

A theory-based behavioral approach to design interventions to improve trial response rates showed small but meaningful improvements. The approach presented here can be easily implemented and adapted to address other identified barriers to trial retention.

Impact of changing provider remuneration on NHS general dental practitioner services in Northern Ireland: a mixed-methods study

Background

Policy-makers wanted to reform the NHS dental contract in Northern Ireland to contain costs, secure access and incentivise prevention and quality. A pilot project was undertaken to remunerate general dental practitioners using a capitation-based payment system rather than the existing fee-for-service system.

Objective

To investigate the impact of this change in remuneration.

Design

Mixed-methods design using a difference-in-difference evaluation of clinical activity levels, a questionnaire of patient-rated outcomes and qualitative assessment of general dental practitioners’ and patients’ views.

Setting

NHS dental practices in Northern Ireland.

Participants

General dental practitioners and patients in 11 intervention practices and 18 control practices.

Interventions

Change from fee for service to a capitation-based system for 1 year and then reversion back to fee for service.

Main outcome measures

Access to care, activity levels, service mix and financial impact, and patient-rated outcomes of care.

Results

The difference-in-difference analyses showed significant and rapid changes in the patterns of care provided by general dental practitioners to patients (compared with the control practices) when they moved from a fee-for-service system to a capitation-based remuneration system. The number of registered patients in the intervention practices compared with the control practices showed a small but statistically significant increase during the capitation period (p < 0.01), but this difference was small. There were statistically significant reductions in the volume of activity across all treatments in the intervention practices during the capitation period, compared with the control practices. This produced a concomitant reduction in patient charge revenue of £2403 per practice per month (p < 0.05). All outcome measures rapidly returned to baseline levels following reversion from the capitation-based system back to a fee-for-service system. The analysis of the questionnaires suggests that patients did not appear to notice very much change. Qualitative interviews showed variation in general dental practitioners’ behaviour in response to the intervention and how they managed the tension between professional ethics and maximising the profits of their business. Behaviours were also heavily influenced by local context. Practice principals preferred the capitation model as it freed up time and provided opportunities for private work, whereas capitation payments were seen by some principals as a ‘retainer fee’ for continuing to provide NHS care. Non-equity-owning associates perceived the capitation model as a financial risk.

Limitations

The active NHS pilot period was only 1 year, which may have limited the scope for meaningful change. The number of sites was restricted by the financial budget for the NHS pilot.

Conclusions

General dental practitioners respond rapidly and consistently to changes in remuneration, but differences were found in the extent of this change by practice and provider type. A move from a fee-for-service system to a capitation-based system had little impact on access but produced large reductions in clinical activity and patient charge income. Patients noticed little difference in the service that they received.

Future work

With changing population need and increasing financial pressure on the NHS, research is required on how to most efficiently meet the expectations of patients within an affordable cost envelope. Work is also needed to identify and evaluate interventions that can complement changes in remuneration to meet policy goals.

Trial registration

Current Controlled Trials ISRCTN29840057.

Funding

This project was funded by the National Institute for Health Research (NIHR) Health Services and Delivery Research programme and will be published in full in Health Services and Delivery Research; Vol. 8, No. 6. See the NIHR Journals Library website for further project information.

Ending the neglect of global oral health: time for radical action

Oral diseases are a major global public health problem affecting over 3·5 billion people. However, dentistry has so far been unable to tackle this problem. A fundamentally different approach is now needed. In this second of two papers in a Series on oral health, we present a critique of dentistry, highlighting its key limitations and the urgent need for system reform. In high-income countries, the current treatment-dominated, increasingly high-technology, interventionist, and specialised approach is not tackling the underlying causes of disease and is not addressing inequalities in oral health. In low-income and middle-income countries (LMICs), the limitations of so-called westernised dentistry are at their most acute; dentistry is often unavailable, unaffordable, and inappropriate for the majority of these populations, but particularly the rural poor. Rather than being isolated and separated from the mainstream health-care system, dentistry needs to be more integrated, in particular with primary care services. The global drive for universal health coverage provides an ideal opportunity for this integration. Dental care systems should focus more on promoting and maintaining oral health and achieving greater oral health equity. Sugar, alcohol, and tobacco consumption, and their underlying social and commercial determinants, are common risk factors shared with a range of other non-communicable diseases (NCDs). Coherent and comprehensive regulation and legislation are needed to tackle these shared risk factors. In this Series paper, we focus on the need to reduce sugar consumption and describe how this can be achieved through the adoption of a range of upstream policies designed to combat the corporate strategies used by the global sugar industry to promote sugar consumption and profits. At present, the sugar industry is influencing dental research, oral health policy, and professional organisations through its well developed corporate strategies. The development of clearer and more transparent conflict of interest policies and procedures to limit and clarify the influence of the sugar industry on research, policy, and practice is needed. Combating the commercial determinants of oral diseases and other NCDs should be a major policy priority.

Routine scale and polish for periodontal health in adults

BACKGROUND

Many dentists or hygienists provide scaling and polishing for patients at regular intervals, even for those at low risk of developing periodontal disease. There is debate over the clinical and cost effectiveness of 'routine scaling and polishing' and the optimal frequency at which it should be provided for healthy adults.A 'routine scale and polish' treatment is defined as scaling or polishing, or both, of the crown and root surfaces of teeth to remove local irritational factors (plaque, calculus, debris and staining), which does not involve periodontal surgery or any form of adjunctive periodontal therapy such as the use of chemotherapeutic agents or root planing. Routine scale and polish treatments are typically provided in general dental practice settings. The technique may also be referred to as prophylaxis, professional mechanical plaque removal or periodontal instrumentation.This review updates a version published in 2013.

OBJECTIVES

1. To determine the beneficial and harmful effects of routine scaling and polishing for periodontal health.2. To determine the beneficial and harmful effects of routine scaling and polishing at different recall intervals for periodontal health.3. To determine the beneficial and harmful effects of routine scaling and polishing for periodontal health when the treatment is provided by dentists compared with dental care professionals (dental therapists or dental hygienists).

SEARCH METHODS

Cochrane Oral Health's Information Specialist searched the following databases: Cochrane Oral Health's Trials Register (to 10 January 2018), the Cochrane Central Register of Controlled Trials (CENTRAL) (the Cochrane Library, 2017, Issue 12), MEDLINE Ovid (1946 to 10 January 2018), and Embase Ovid (1980 to 10 January 2018). The US National Institutes of Health Trials Registry (ClinicalTrials.gov) and the World Health Organization International Clinical Trials Registry Platform were searched for ongoing trials. No restrictions were placed on the language or date of publication when searching the electronic databases.

SELECTION CRITERIA

Randomised controlled trials of routine scale and polish treatments, with or without oral hygiene instruction, in healthy dentate adults without severe periodontitis. We excluded split-mouth trials.

DATA COLLECTION AND ANALYSIS

Two review authors screened the results of the searches against inclusion criteria, extracted data and assessed risk of bias independently and in duplicate. We calculated mean differences (MDs) (or standardised mean differences (SMDs) when different scales were reported) and 95% confidence intervals (CIs) for continuous data. We calculated risk ratios (RR) and 95% CIs for dichotomous data. We used a fixed-effect model for meta-analyses. We contacted study authors when necessary to obtain missing information. We rated the certainty of the evidence using the GRADE approach.

MAIN RESULTS

We included two studies with 1711 participants in the analyses. Both studies were conducted in UK general dental practices and involved adults without severe periodontitis who were regular attenders at dental appointments. One study measured outcomes at 24 months and the other at 36 months. Neither study measured adverse effects, changes in attachment level, tooth loss or halitosis.Comparison 1: routine scaling and polishing versus no scheduled scaling and polishingTwo studies compared planned, regular interval (six- and 12-monthly) scale and polish treatments versus no scheduled treatment. We found little or no difference between groups over a two- to three-year period for gingivitis, probing depths, oral health-related quality of life (all high-certainty evidence) and plaque (low-certainty evidence). The SMD for gingivitis when comparing six-monthly scale and polish treatment versus no scheduled treatment was -0.01 (95% CI -0.13 to 0.11; two trials, 1087 participants), and for 12-monthly scale and polish versus no scheduled treatment was -0.04 (95% CI -0.16 to 0.08; two trials, 1091 participants).Regular planned scale and polish treatments produced a small reduction in calculus levels over two to three years when compared with no scheduled scale and polish treatments (high-certainty evidence). The SMD for six-monthly scale and polish versus no scheduled treatment was -0.32 (95% CI -0.44 to -0.20; two trials, 1088 participants) and for 12-monthly scale and polish versus no scheduled treatment was -0.19 (95% CI -0.31 to -0.07; two trials, 1088 participants). The clinical importance of these small reductions is unclear.Participants' self-reported levels of oral cleanliness were higher when receiving six- and 12-monthly scale and polish treatments compared to no scheduled treatment, but the certainty of the evidence is low.Comparison 2: routine scaling and polishing at different recall intervalsTwo studies compared routine six-monthly scale and polish treatments versus 12-monthly treatments. We found little or no difference between groups over two to three years for the outcomes of gingivitis, probing depths, oral health-related quality of life (all high-certainty evidence) and plaque (low-certainty evidence). The SMD for gingivitis was 0.03 (95% CI -0.09 to 0.15; two trials, 1090 participants; I² = 0%). Six- monthly scale and polish treatments produced a small reduction in calculus levels over a two- to three-year period when compared with 12-monthly treatments (SMD -0.13 (95% CI -0.25 to -0.01; 2 trials, 1086 participants; high-certainty evidence). The clinical importance of this small reduction is unclear.The comparative effects of six- and 12-monthly scale and polish treatments on patients' self-reported levels of oral cleanliness were uncertain (very low-certainty evidence).Comparison 3: routine scaling and polishing provided by dentists compared with dental care professionals (dental therapists or hygienists)No studies evaluated this comparison.The review findings in relation to costs were uncertain (very low-certainty evidence).

AUTHORS' CONCLUSIONS

For adults without severe periodontitis who regularly access routine dental care, routine scale and polish treatment makes little or no difference to gingivitis, probing depths and oral health-related quality of life over two to three years follow-up when compared with no scheduled scale and polish treatments (high-certainty evidence). There may also be little or no difference in plaque levels over two years (low-certainty evidence). Routine scaling and polishing reduces calculus levels compared with no routine scaling and polishing, with six-monthly treatments reducing calculus more than 12-monthly treatments over two to three years follow-up (high-certainty evidence), although the clinical importance of these small reductions is uncertain. Available evidence on the costs of the treatments is uncertain. The studies did not assess adverse effects.

One-to-one oral hygiene advice provided in a dental setting for oral health

BACKGROUND

Effective oral hygiene measures carried out on a regular basis are vital to maintain good oral health. One-to-one oral hygiene advice (OHA) within the dental setting is often provided as a means to motivate individuals and to help achieve improved levels of oral health. However, it is unclear if one-to-one OHA in a dental setting is effective in improving oral health and what method(s) might be most effective and efficient.

OBJECTIVES

To assess the effects of one-to-one OHA, provided by a member of the dental team within the dental setting, on patients' oral health, hygiene, behaviour, and attitudes compared to no advice or advice in a different format.

SEARCH METHODS

Cochrane Oral Health's Information Specialist searched the following databases: Cochrane Oral Health's Trials Register (to 10 November 2017); the Cochrane Central Register of Controlled Trials (CENTRAL; 2017, Issue 10) in the Cochrane Library (searched 10 November 2017); MEDLINE Ovid (1946 to 10 November 2017); and Embase Ovid (1980 to 10 November 2017). The US National Institutes of Health Ongoing Trials Register (ClinicalTrials.gov) and the World Health Organization International Clinical Trials Registry Platform were also searched for ongoing trials (10 November 2017). No restrictions were placed on the language or date of publication when searching the electronic databases. Reference lists of relevant articles and previously published systematic reviews were handsearched. The authors of eligible trials were contacted, where feasible, to identify any unpublished work.

SELECTION CRITERIA

We included randomised controlled trials assessing the effects of one-to-one OHA delivered by a dental care professional in a dental care setting with a minimum of 8 weeks follow-up. We included healthy participants or participants who had a well-defined medical condition.

DATA COLLECTION AND ANALYSIS

At least two review authors carried out selection of studies, data extraction and risk of bias independently and in duplicate. Consensus was achieved by discussion, or involvement of a third review author if required.

MAIN RESULTS

Nineteen studies met the criteria for inclusion in the review with data available for a total of 4232 participants. The included studies reported a wide variety of interventions, study populations, clinical outcomes and outcome measures. There was substantial clinical heterogeneity amongst the studies and it was not deemed appropriate to pool data in a meta-analysis. We summarised data by categorising similar interventions into comparison groups.Comparison 1: Any form of one-to-one OHA versus no OHAFour studies compared any form of one-to-one OHA versus no OHA.Two studies reported the outcome of gingivitis. Although one small study had contradictory results at 3 months and 6 months, the other study showed very low-quality evidence of a benefit for OHA at all time points (very low-quality evidence).The same two studies reported the outcome of plaque. There was low-quality evidence that these interventions showed a benefit for OHA in plaque reduction at all time points.Two studies reported the outcome of dental caries at 6 months and 12 months respectively. There was very low-quality evidence of a benefit for OHA at 12 months.Comparison 2: Personalised one-to-one OHA versus routine one-to-one OHAFour studies compared personalised OHA versus routine OHA.There was little evidence available that any of these interventions demonstrated a difference on the outcomes of gingivitis, plaque or dental caries (very low quality).Comparison 3: Self-management versus professional OHAFive trials compared some form of self-management with some form of professional OHA.There was little evidence available that any of these interventions demonstrated a difference on the outcomes of gingivitis or plaque (very low quality). None of the studies measured dental caries.Comparison 4: Enhanced one-to-one OHA versus one-to-one OHASeven trials compared some form of enhanced OHA with some form of routine OHA.There was little evidence available that any of these interventions demonstrated a difference on the outcomes of gingivitis, plaque or dental caries (very low quality).

AUTHORS' CONCLUSIONS

There was insufficient high-quality evidence to recommend any specific one-to-one OHA method as being effective in improving oral health or being more effective than any other method. Further high-quality randomised controlled trials are required to determine the most effective, efficient method of one-to-one OHA for oral health maintenance and improvement. The design of such trials should be cognisant of the limitations of the available evidence presented in this Cochrane Review.

Patient perceptions regarding benefits of single visit scale and polish: a randomised controlled trial

BACKGROUND

Single visit scale and polish is frequently carried out in dental practices however there is little evidence to support (or refute) its clinical effectiveness. The purpose of this research was to compare patient-reported outcomes between groups receiving a scale and polish at 6-, 12-, and 24-month intervals. Outcomes recorded included participants' subjective assessment of their oral cleanliness; the perceived importance of scale and polish for oral health and aesthetics; and frequency at which this treatment is required.

METHODS

A practice-based randomised control trial was undertaken, with a 24-month follow-up period. Participants were healthy adults with no significant periodontal disease (BPE codes <3) randomly allocated to three groups to receive scale and polish at 6-, 12-, or 24-month intervals. Patient-reported outcomes were recorded at baseline and follow-up. Oral cleanliness was reported using a 5-point scale and recorded by examiners blinded to trial group allocation. A self-completed questionnaire enabled participants to report perceived importance of scale and polish (5-point scale), and required frequency of treatment (6-point scale). The main hypothesis was that participants receiving 6-monthly scale and polish would report higher levels of oral cleanliness compared to participants receiving scale and polish at 12- and 24-month intervals.

RESULTS

369 participants were randomised: 125 to the 6-month group; 122 to the 12-month group; and 122 to the 24-month group. Complete data set analysis was carried out to include 107 (6-month group), 100 (12-month group) and 100 (24-month group) participants. Multiple imputation analyses were conducted where follow-up data was missing. The difference in the proportions of participants reporting a 'high' level of oral cleanliness at follow-up was significant (Chi-squared P = 0.003): 52.3% (6-month group), 47.0% (12-month group) and 30.0% (24-month group). Scale and polish was thought to be important by the majority in each group for keeping mouths clean and gums healthy, whitening teeth, and preventing bad breath and tooth decay; there were no statistically significant differences between groups at follow-up. Most participants at follow-up thought that the frequency of scale and polish should be "every 6 months" or more frequently: 77.9% (6-month group), 64.6% (12-month group), 71.7% (24-month group); differences between groups were not statistically significant (Chi squared P = 0.126). The results suggest that participants in the 24-month trial group were more likely to choose a scale and polish interval of "once a year" or less frequently (OR 2.89; 95% CI 1.36, 6.13).

CONCLUSIONS

The majority of healthy adults regarded 6-monthly single-visit scale and polish as being beneficial for their oral health. Receiving the treatment at different frequencies did not alter this belief; and those with the longest interval between scale and polish provision perceived that their mouth was less clean. In the absence of a strong evidence base to support (or refute) the effectiveness of single-visit scale and polish, the beliefs and preferences of patients regarding scale and polish may be influential drivers for maintaining provision of this treatment.

Clinical outcomes of single-visit oral prophylaxis: a practice-based randomised controlled trial

BACKGROUND

Practice-based general dental practitioners routinely provide "scale and polish" or "oral prophylaxis" to patients attending their practices. Despite its routine provision, there is no evidence to support the clinical effectiveness of single-visit scale and polish, nor the frequency at which it should be provided. A recent systematic review recommended that future trials investigating scale and polish should involve dental practice patients.

METHODS

A practice-based parallel randomised controlled trial with 24-month follow-up was conducted. Healthy adults (Basic Periodontal Examination [BPE] codes <3) were randomly assigned to 3 groups (6-month, 12-month, or 24-month interval between scale and polish). The primary outcome was gingival bleeding with the hypothesis that 6-monthly scale and polish would result in lower prevalence than 12-month or 24-month frequency. Follow-up measurements were recorded by examiners blinded to the allocation. 125, 122 and 122 participants were randomised to the 6-month, 12-month and 24-month groups respectively. Complete data set analyses were conducted for 307 participants: 107, 100, and 100 in the 6-month, 12-month and 24-month groups respectively. Chi-square test and ANOVA were used to compare treatment groups at follow-up. Logistic regression and ANCOVA were used to estimate the relationship between outcome and treatment group, adjusted for baseline values. Multiple imputation analyses were also carried out for participants with incomplete data sets.

RESULTS

Prevalence of gingival bleeding at follow-up was 78.5% (6-month), 78% (12-month) and 82% (24-month) (p = 0.746). There were no statistically significant differences between groups with respect to follow-up prevalence of plaque and calculus. Statistically significant differences detected in the amount (millimetres) of calculus were too small to be clinically significant. Seventeen (4.6%) participants were withdrawn from the trial to receive additional treatment.

CONCLUSIONS

This trial could not identify any differences in outcomes for single-visit scale and polish provided at 6, 12 and 24 month frequencies for healthy patients (with no significant periodontal disease). However, this is the first trial of scale and polish which has been conducted in a general practice setting and the results are not conclusive. Larger trials with more comprehensive measurement and long-term follow up need to be undertaken to provide a firm evidence base for this intervention. This trial informs the design of future practice-based trials on this subject.