Peter A. Heasman

Response of subgingival bacteria to smoking cessation.

ABSTRACT It has been demonstrated that smoking cessation alters the subgingival microbial profile; however, the response of individual bacteria within this ecosystem has not been well studied. The aim of this investigation, therefore, was to longitudinally examine the effect of smoking cessation on the prevalence and levels of selected subgingival bacteria using molecular approaches for bacterial identification and enumeration. Subgingival plaque was collected from 22 smokers at the baseline and 12 months following periodontal nonsurgical management and smoking cessation counseling. The prevalence and abundance of selected organisms were examined using nested PCR and multiplexed bead-based flow cytometry. Eleven subjects successfully quit smoking over 12 months (quitters), while 11 continued to smoke throughout (smokers). Smoking cessation led to a decrease in the prevalence of Porphyromonas endodontalis and Dialister pneumosintes at 12 months and in the levels of Parvimonas micra, Filifactor alocis, and Treponema denticola. Smoking cessation also led to an increase in the levels of Veillonella parvula. Following nonsurgical periodontal therapy and smoking cessation, the subgingival microbiome is recolonized by a greater number of health-associated species and there are a significantly lower prevalence and abundance of putative periodontal pathogens. The results indicate a critical role for smoking cessation counseling in periodontal therapy for smokers in order to effectively alter the subgingival microbiome.

Smoking Cessation Alters Subgingival Microbial Recolonization

Smoking cessation improves the clinical manifestations of periodontitis; however, its effect on the subgingival biofilm, the primary etiological agent of periodontitis, is unclear. The purpose of this study was to investigate, longitudinally, if smoking cessation altered the composition of the subgingival microbial community, by means of a quantitative, cultivation-independent assay for bacterial profiling. Subgingival plaque was collected at baseline, and 3, 6, and 12 months post-treatment from smokers who received root planing and smoking cessation counseling. The plaque was analyzed by terminal restriction fragment length polymorphism (t-RFLP). Microbial profiles differed significantly between smokers and quitters at 6 and 12 months following smoking cessation. The microbial community in smokers was similar to baseline, while quitters demonstrated significantly divergent profiles. Changes in bacterial levels contributed to this shift. These findings reveal a critical role for smoking cessation in altering the subgingival biofilm and suggest a mechanism for improved periodontal health associated with smoking cessation.

Smoking cessation as a dental intervention — Views of the profession

Objective To undertake a questionnaire-based survey to determine the attitudes and activities of dental professionals in primary care in the Northern Deanery of the UK in relation to providing smoking cessation advice.Methods Questionnaires for dentists, hygienists and dental nurses were sent to hygienists to distribute to other members of the team. The information collected included: smoking status of the professionals and the practice; roles of the dental team in giving smoking cessation advice; levels of training received; and potential barriers to giving this brief intervention.Results Over 90% of practices were smoke-free environments and significantly more dental nurses (23%) were smokers compared to dentists (10%) and hygienists (7%) (p<0.01). The majority of dentists and hygienists enquired about smoking status of their patients and all three groups believed that hygienists and dentists should offer brief smoking cessation advice. Potential barriers to delivering smoking cessation advice were identified: lack of remuneration; lack of time; and lack of training.Conclusion Dental teams in primary care are aware of the importance of offering smoking cessation advice and, with further training and appropriate remuneration, could guide many of their patients who smoke to successful quit attempts.

Smoking cessation advice for patients with chronic periodontitis

Background There are limited data on the utility of dental professionals in providing smoking cessation counselling in the UK.Objectives The purpose of this study was to determine quit rates for smokers with chronic periodontitis who were referred to a dental hospital for treatment.Materials and methods Forty-nine subjects with chronic periodontitis who smoked cigarettes were recruited. All subjects received periodontal treatment and smoking cessation advice as part of an individual, patient-based programme provided by dental hygienists trained in smoking cessation counselling. Smoking cessation interventions included counselling (all patients), and some patients also received nicotine replacement therapy (NRT) and/or Zyban medication. Smoking cessation advice was given at each visit at which periodontal treatment was undertaken (typically four to six visits) over a period of 10-12 weeks. Smoking cessation advice was also given monthly during the programme of supportive periodontal care over the following nine months. Smoking status was recorded at three, six and 12 months and was confirmed with carbon monoxide (CO) monitors and salivary cotinine assays.Results Forty-one per cent, 33%, 29% and 25% of patients had stopped smoking at week four, months three, six and 12, respectively. Gender, age, the presence of another smoker in the household, and baseline smoking status (determined using subject-reported pack years of smoking) were not significant predictors of quit success (P < 0.05). Baseline CO levels were significantly associated with quit success, however, and were significantly higher in those subjects who continued to smoke compared to those subjects who were quitters at week four, month three and month six (P < 0.05).Conclusion Success rates in quitting smoking following smoking cessation advice given as part of a periodontal treatment compared very favourably to national quit rates achieved in specialist smoking cessation clinics. The dental profession has a crucial role to play in smoking cessation counselling, particularly for patients with chronic periodontitis.

The cost-effectiveness of supportive periodontal care: A global perspective

AIM To evaluate the cost-effectiveness of supportive periodontal care (SPC) provided in generalist and periodontal specialist practices under publicly subsidized or private dental care. MATERIAL AND METHODS SPC cost data and the costs of replacing teeth were synthesized with estimates of the effectiveness of SPC in preventing attachment and tooth loss and adjusted for differences in clinicians time. Incremental cost-effectiveness ratios were calculated for both outcomes assuming a time horizon of 30 years. RESULTS SPC in specialist periodontal practice provides improved outcomes but at higher costs than SPC provided by publicly subsidized or private systems. SPC in specialist periodontal practice is usually more cost-effective than in private dental practice. For private dental practices in Spain, United Kingdom and Australia, specialist SPC is cost-effective at modest values of attachment loss averted. Variation in the threshold arises primarily from clinicians time. CONCLUSION SPC in specialist periodontal practice represents good value for money for patients (publicly subsidized or private) in the United Kingdom and Australia and in Spain if they place relatively modest values on avoiding attachment loss. For patients in Ireland, Germany, Japan and the United State, a higher valuation on avoiding attachment loss is needed to justify SPC in private or specialist practices.

The impact of powered and manual toothbrushing on incipient gingival recession

AIM To compare clinical effects of manual and powered toothbrushes on sites of localized gingival recession over 12 months. To evaluate patterns and the extent of toothbrush bristle wear. METHODS A longitudinal, single-blind, randomized, parallel group clinical trial compared the effects of one manual and one powered toothbrush on incipient lesions of localized gingival recession. Toothbrush wear was evaluated concurrently by wear index and wear rating. RESULTS Sixty patients were recruited and randomized to two groups with 52 (26 per group) attending the final visit at month 12. There were no differences between groups for full-mouth plaque index, pocket depth or bleeding on probing at baseline and month 12. There were no differences at target sites for clinical attachment level, pocket depth, bleeding on probing, plaque index, width of keratinized gingiva or maximal height of recession. There were no differences between the wear of the brushes as measured by wear index or wear rating. CONCLUSION There was no progression of gingival recession in subjects using either toothbrush over 12 months. There was no difference in the overall wear of the powered and manual toothbrushes over successive 3-month periods.

How to measure the cost‐effectiveness of periodontal treatments

There is a need to measure efficiency of periodontal treatments. Efficiency questions can be addressed through a variety of economic evaluation techniques: cost minimization, cost-effectiveness, cost utility and cost-benefit analysis. Each of these techniques is outlined in this article, including a detailed discussion of different preference-based outcome (utility) measures. Despite the need, few analyses have been undertaken in periodontology. There are several issues in undertaking cost-effectiveness analyses specific to periodontology and these are examined in detail: outcome measures including patient-based vs. clinical measures of outcome; discounting or taking into account time preference for outcomes and costs; problems of costing, including the perspective taken in an analysis; interpreting the evidence, in particular using incremental cost-effectiveness ratios; and global variation in periodontal care delivery, including healthcare systems and the use of hygienists. The need for cost-effectiveness analysis in periodontology is explored further, and the need to involve a health economist in such an evaluation is underlined.

Dinucleotide repeat polymorphism in the interleukin-10 gene promoter (IL-10.G) and genetic susceptibility to early-onset periodontal disease.

Emerging evidence suggests that certain genetic polymorphisms are associated with various sub-groups of early-onset periodontal diseases (EOP). We determined the genotype with respect to a (CA)n dinucleotide repeat polymorphism in the promoter region of the interleukin-10 gene (IL-10.G) in 72 patients with EOP and in 73 healthy individuals in order to test for possible disease associations. Some differences between the frequency of individual IL.10.G alleles in the patients groups as compared to the healthy controls were detected. For example the frequency of the IL-10.G9 allele in a clinical sub-group of the EOP patients with localised disease (L-EOP, n = 21) was 64.3% as compared to 41.8% in the controls. However, statistical analysis (Monte Carlo simulation) revealed that the differences in IL-10.G allele distribution between the healthy controls and both the EOP group and the L-EOP group were not statistically significant. We conclude that this study provides no evidence for a role of IL-10.G alleles in genetic susceptibility to EOP.

Drugs, medications and periodontal disease

This paper reviews the effects that drugs may have on the gingival and periodontal tissues. Drug-induced gingival overgrowth has been recognised for over 70 years but is becoming a more prevalent occurrence with wider use of antihypertensive and immunosuppressant drugs. The anti-inflammatory steroids, non-steroidal drugs and anti-TNF-α agents might all be expected to exert a dampening effect on chronic periodontitis although the evidence is somewhat equivocal and none of these drugs has emerged as potentially valuable adjuncts to treat periodontal disease. Desquamative gingivitis is a clinical appearance of aggressive gingival inflammation with which a number of drugs have been associated and the oral contraceptives have also been implicated in the development of gingival inflammation. Patients who are prescribed bisphosphonates and anti-platelet drugs are at risk of serious side effects following more invasive dental procedures including extractions and surgical treatments although timely, conventional management of periodontal disease may be undertaken to reduce periodontal inflammation, prevent disease progression and ultimately the need for extractions.

Making the leap from cost analysis to cost‐effectiveness

Cost-effectiveness is increasingly being recognized as an important aspect of the evaluation of dental treatments and interventions (Braegger 2005). Economic analysis of periodontal treatment dates back to a seminal paper by (Antczak-Bouckoms & Weinstein 1987), and more recently, has been a focus of discussion at the 6th European Workshop on Periodontology, where it was recognized that interventions such as supportive periodontal or maintenance care can lend themselves to this method of evaluation (Gaunt et al. 2008, Sanz & Teughels 2008). A paper in this issue of the Journal (Pretzl et al. 2009) examines the cost of supportive periodontal treatment (SPT) and makes comparisons with the cost of prosthetic options for replacing lost teeth. The authors provide both a thorough analysis of the factors that influence those costs and useful data on the cost-effectiveness of SPT. It is timely, therefore, to take the opportunity to review the essential steps required to establish cost-effectiveness that must extend beyond a simple comparison of two or more interventions, in this case, the cost of SPT with the cost of prosthetic replacements. A treatment that is cost-effective is one for which the benefits of that treatment exceed the costs. The benefits of dental treatment in general include the improved or retained functionality and aesthetics of the natural dentition and the discomfort of treatment (a limitation) as valued by the patient. The different types of economic evaluation namely, cost benefit analysis (CBA), cost-effectiveness analysis (CEA) and cost utility analysis (CUA), vary in the way in which they value these benefits. Cost Benefit Analysis, for example, seeks to attach a monetary value to the benefits (Sugden & Williams 1979) whereas CUA uses a quality-of-life measure such as the Quality Adjusted Life Year (Broome 1993). CEA only seeks to compare outcomes on an appropriate quantitative scale (Gold et al. 1996). A common mistake in dentistry and other areas of healthcare provision is to make the assumption that the benefits of treatment are simply the costs averted by that treatment (Davies 1973, Crowley et al. 2000). The costs averted by a treatment should always be included, but as a negative cost. The importance of assigning costs correctly in an economic analysis has been discussed previously (Birch & Donaldson 1987), with an emphasis on the need to determine the incremental cost of treatment, which is: