Gingival bleeding on probing increases after quitting smoking

Association of Sleep Quality and General, Mental, and Oral Health with Lifestyle Traits (Dietary Intake, Smoking Status) in Arthritis: A Cross-Sectional Study from the Canadian Community Health Survey (CCHS)

Arthritis is associated with health challenges. Lifestyle traits are believed to influence arthritis development and progression; however, data to support personalized treatment regimens based on holistic lifestyle factors are missing. This study aims to provide a comprehensive list of associations between lifestyle traits and the health status of individuals with arthritis in the Canadian population, using binary logistic regression analysis on data from the Canadian Community Health Survey, which includes 104,359 respondents. Firstly, we explored the association between arthritis and various aspects of health status including self-reported lifestyle factors. Secondly, we examined the associations between self-reported dietary intake and smoking status with general, mental, and oral health, and sleep disturbance among individuals both with and without arthritis. Our analysis revealed that individuals with arthritis reported considerably poorer general, mental, and oral health, and poorer sleep quality compared to those without arthritis. Associations were also found between self-reported dietary intake and various measures of health status in individuals with arthritis. Smoking and exposure to passive smoking were associated not only with arthritis but also with compromised sleep quality and poorer general, mental, and oral health in people with and without arthritis. This study highlights the need for personalized and holistic approaches that may include a combination of dietary interventions, oral health improvements, sleep therapies, and smoking cessation for improved arthritis prevention and care.

Effectiveness of photodynamic therapy adjunct to oral debridement in improving clinical, microbiological, and pain in necrotizing ulcerative gingivitis

To evaluate the efficacy of photodynamic therapy (PDT) as adjunctive to oral debridement (OD) in the improvement of clinical, microbiological, and pain in patients with necrotizing ulcerative gingivitis (NUG). Patients with NUG were split into two groups: Group-OD + PDT received PDT with OD, while Group-OD underwent OD alone. Clinical inflammatory parameters including full mouth plaque scores (FMPS), full mouth bleeding scores (FMBS), and probing depth (PD) were assessed. Fusobacterium nucleatum and Prevotella intermedia were analyzed using the polymerase chain reaction technique. Pain examination was done using various pain scales. Group PDT + OD showed more reduction in FMPS, FMBS, and greater reduction in F. nucleatum and P. intermedia count compared to group OD at 12 weeks follow up (p < 0.01). Group PDT + OD showed significantly lower pain scores at 12 weeks (p < 0.05). PDT was more effective in improving clinical parameters, and reducing bacterial counts and pain in NUG patients than dental scaling alone.

Antimicrobial photodynamic therapy using chloro-aluminum phthalocyanine for treating advanced stage-III periodontitis in smoking patients

PURPOSE

To evaluate the bacterial, clinical, and cytokine profile of adjunctive photodynamic therapy using chloro-aluminum phthalocyanine (CAP/aPDT) with root surface debridement (RSD) versus RSD alone in cigarette smokers (CS) and never-smokers (NS) during the period of 6 months.

METHODS

Twenty-nine patients [CS - 14 and NS - 15] were recruited for the trial having stage-III periodontitis. All candidates from the study groups were subjected to a split-mouth treatment technique receiving CAP/aPDT + RSD and RSD alone. Periodontal parameters including plaque levels (PL), bleeding on probing (BP), probing depth (PD), clinical attachment loss (CAL), and marginal bone loss (MBL) were assessed. Polymerase chain reaction (qPCR) assay was used to analyze the copy numbers of Porphyromonas gingivalis (Pg) and Tannerella forsythia (Tf). Levels of tumor necrosis factor-alpha (TNF-α) interleukin (IL)-6 in the crevicular fluid were evaluated by enzyme-linked immunosorbent assay (ELISA).

RESULTS

CAP/aPDT+RSD decreased BP in smokers after 6 months (p < .05). Probing depth and CAL reported statistically significant reductions within both CAP/aPDT+RSD and RSD groups and also within the NS and CS (p < .05). Pg and Tf stayed elevated in smokers at the 6-month evaluation period (p < .01). Only CAP/aPDT+RSD significantly decreased Pg and Tf at 3- and 6-month follow-up in smokers (p < .05). CAP/aPDT+RSD showed decreased IL-6 levels in the NS during the 6-month follow-up (p < .01). TNF-α levels were significantly reduced in the CS group with CAP/aPDT+RSD and RSD alone until 6 months (p < .01).

CONCLUSION

CAP-mediated aPDT along with nonsurgical periodontal therapy helped to improve the bacteriological outcomes among smokers and never-smokers with stage-III CP patients.

Chloro-aluminum phthalocyanine-mediated photodynamic therapy in the treatment of stage-II chronic periodontitis among smokers

PURPOSE

To assess the clinical periodontal, bacterial, and immunological outcomes of chloro-aluminum phthalocyanine-mediated photodynamic therapy (PDT) as an adjunct to dental scaling (DS) versus DS alone among cigarette smokers (CS) and never-smokers (NS).

METHODS

A total of 26 patients (13 CS and 13 NS) with clinical and radiographic diagnosis of stage-II chronic periodontitis were recruited. Each patient from both groups were subjected with two parallel therapies (split-mouth): PDT + DS (test side) and DS alone (control side). Periodontal parameters were investigated by evaluating plaque scores (PS), bleeding on probing (BOP), probing depth (PD), clinical attachment loss (CAL), and alveolar bone loss (ABL). Subgingival plaque was collected to detect and quantify Porphyromonas gingivalis and Tannerella forsythia using real-time quantitative polymerase chain reaction (RT-qPCR) assay. Gingival crevicular fluid was sampled for the quantification of interleukin (IL)-1β and tumor necrosis factor-alpha (TNF-α) using enzyme linked immunosorbent assay. All assessments were performed at baseline, 3 months, and 6 months.

RESULTS

Bleeding on probing was significantly reduced at 6 months after PDT + DS in CS groups (p < .05). Mean PD and CAL significantly reduced after both PDT + DS and DS subgroups and among NS and CS groups (p < .05). At 6 months follow-up, the copy number of both P. gingivalis and T. forsythia remained significantly high in CS group (p < .01). Only PDT + DS subgroup in CS significantly reduced the counts of P. gingivalis and T. forsythia at 3 months and 6 months (p < .05). Only at 6 months did PDT + DS showed statistically significantly reduced IL-1β levels in the NS group (p < .01). TNF-α levels significantly reduced in CS group with PDT + DS and DS alone at both 3 months and 6 months follow-up (p < .01).

CONCLUSION

Chloro-aluminum phthalocyanine-mediated PDT helped to improve the non-surgical periodontal therapy outcomes among stage-II chronic periodontitis patients among smokers and never-smokers.

The role of cigarette smoking in periodontal disease and treatment outcomes of dental implant therapy

Tobacco smoking has been implicated in periodontal pathology through various mechanisms, including perturbations of the inflammatory and host responses to putative periodontal pathogens, alterations in the subgingival microbial communities, and a compromised healing potential of the tissues leading to imbalance of tissue homeostasis. This review provides the evidence for the relationship between cigarette smoking and periodontal disease in an attempt to explain possible mechanisms of how tobacco smoking may exert its negative effects on the periodontal tissues via systemic and localized pathways. Early and more recent studies explore cigarette smoking-induced changes in periodontal clinical indices; in subgingival microbial flora by employing traditional detection methods for selected microorganisms, in addition to modern techniques such as deep sequencing and bioinformatics analyses that are able to fully characterize the microbial communities; and in inflammatory and immune responses critically appraising study limitations and differences in study protocol designs. Periodontal treatment outcomes and implant therapy outcomes are reviewed in an attempt to shed light on possible mechanisms for the inferior treatment outcome noted in smokers. The potential harmful effects of passive smoking are also reviewed, providing evidence for the advantages of smoking cessation. Quitting cigarette smoking should be recommended by the dentist, and effort should be made to inform smokers about the negative effects of smoking on the periodontal status and implant therapy outcomes.

Oral Health in the Population Assessment of Tobacco and Health Study

Tobacco use is a well-established risk factor for multiple adverse oral conditions. Few nationally representative oral health data sets encompass the current diversity of tobacco and nicotine products. This investigation examines the validity of oral health measures in the Population Assessment of Tobacco and Health (PATH) Study to assess relationships between tobacco use and oral health. Cross-sectional data from PATH Study wave 4 (N = 33,643 US adults, collected 2016-2018) were used to obtain estimates for 6 self-reported oral conditions (e.g., bone loss around teeth, tooth extractions) and compared with analogous estimates from the National Health and Nutrition Examination Survey (NHANES) cycle 2017-2018 (N = 5,856). Within the PATH Study, associations were calculated between tobacco use status and lifetime and past 12-mo experience of adverse oral conditions using survey-weighted multivariable logistic regression. Nationally representative estimates of oral conditions between the PATH Study and NHANES were similar (e.g., ever-experience of bone loss around teeth: PATH Study 15.2%, 95% CI, 14.4%-15.9%; NHANES 16.6%, 95% CI, 14.9%-18.4%). In the PATH Study, combustible tobacco smoking was consistently associated with lifetime and past 12-mo experience of adverse oral health (e.g., exclusive cigarette smoking vs. never tobacco use, adjusted odds ratio [AOR] for loose teeth in past 12 mo: 2.02; 95% CI, 1.52-2.69). Exclusive smokeless tobacco use was associated with greater odds of loose teeth (AOR, 1.93; 95% CI, 1.15-3.26) and lifetime precancerous lesions (AOR, 3.85; 95% CI, 1.73-8.57). Use of other noncigarette products (e.g., pipes) was inconsistently associated with oral health outcomes. PATH Study oral health measures closely align with self-reported measures from NHANES and are internally concurrent. Observed associations with tobacco use and the ability to examine emerging tobacco products support application of PATH Study data in dental research, particularly to examine potential oral health effects of novel tobacco products and longitudinal changes in tobacco use behaviors.

Effect of switching from cigarette smoking to the use of the tobacco heating system on periodontitis treatment outcome: Periodontal parameter results from a multicenter Japanese study

Objectives

We conducted a 6-month randomized clinical study to evaluate the impact of exposure to the aerosol of the Tobacco Heating System (THS), a smoke-free alternative to cigarettes, on changes in periodontal parameters after scaling and root planing (SRP) for periodontitis in subjects who were either continuing to smoke cigarettes or had switched to THS.

Material and methods

Smokers with generalized periodontitis were randomized to continue smoking cigarettes or switch to THS use. They underwent SRP for up to 8 weeks, with dental assessments conducted at baseline and at 3 and 6 months after the first treatment.

Results

After SRP treatment, all groups showed improvements in the mean full-mouth probing depth (PD), full-mouth clinical attachment level (CAL), gingival inflammation score, plaque control record (PCR), and bleeding on probing (BoP). There were no statistically significant intergroup differences. However, as compared to smokers, THS users showed a trend toward more favorable outcomes in BoP, PCR, and PD improvement at sites with higher initial PD (≥7 mm).

Conclusions

Our results indicate that SRP improves the course of periodontitis similarly in cigarette smokers and THS users. The beneficial effects of this treatment might mask the favorable changes that may occur upon modifying one of the several periodontitis risk factors, such as cigarette smoking.

Clinical trial registration

ClinicalTrials.gov, identifer: NCT03364751.

Gingival bleeding and pocket depth among smokers and the related changes after short-term smoking cessation

BACKGROUND

Smoking is associated with the deteriorating health of the gingiva and periodontium. The long-term beneficial effects of smoking cessation on oral health are well known. However, the effects of short-term smoking cessation on gingival bleeding and periodontal pocket depth are unknown. The purpose of the present study was to determine the effects of short-term smoking cessation on gingival bleeding and periodontal pocket depth.

METHODS

Dentate smokers with a mean age of 56.9 ± 14.4 years at an outpatient smoking cessation clinic participated in this study. A professional dentist checked the periodontal pocket depth and gingival bleeding. Patients visited the smoking cessation clinic on their first visit and 2, 4, 8, and 12 weeks (three months). The gingival assessment was re-performed in those who succeeded in smoking cessation 3 months after the baseline.

RESULTS

The baseline data of 83 patients showed that an increase in pocket depth was associated with increasing age and the amount of smoking. A significant increase in gingival bleeding (p = .031) and increase in pocket depth (p = .046) were observed 3 months after the baseline in patients who successfully quit smoking (n = 14).

CONCLUSION

Short-term smoking cessation increased periodontal pocket depth and gingival bleeding. These findings may reflect healing processes that occur in the healthy gingiva.

IMPLICATIONS

Study findings will be useful to advise patients during smoking cessation programs. Dentists can inform patients that an initial increase in gingival bleeding and pocket depth could be associated with smoking cessation. Such advice will prevent patients from any apprehension that may cause them to recommence smoking.

Association between cumulative smoking exposure, span since smoking cessation, and peri-implantitis: a cross-sectional study

OBJECTIVES

To investigate the association of cumulative smoking exposure and span since smoking cessation with the occurrence of peri-implantitis.

METHODS

A sample of 350 individuals aged ≥ 35 years, with the presence of at least one osseointegrated implant functioning for > 5 years, were enrolled in the study. According to smoking habits, participants were categorized into 3 groups: non-smokers (NS; n = 212), former smokers (FC; n = 66), and current smokers (CS; n = 72). Complete peri-implant and periodontal examinations were evaluated. Associations between the occurrence of peri-implantitis and smoking habits, as well as potential confounders, were evaluated through univariate and multivariate analyses.

RESULTS

The occurrence of peri-implantitis in the NS, FS, and CS groups was 18.2%, 19.7%, and 30.5%, respectively. A high prevalence of the overall number of cases with periodontitis (54.2%) was observed in the CS group when compared to the FS and NS groups. After adjusting for confounders, the odds ratio (OR) for the occurrence of peri-implantitis was 2.63 (1.39-6.77; p < 0.001) for CS compared to NS. There was a significant dose-response relationship between pack/year of smoking and the occurrence of peri-implantitis, as well as a significant decrease in the risk as the years of smoking cessation increased.

CONCLUSIONS

The occurrence of peri-implantitis among CS was high. The cumulative smoking exposure in an incremental manner and the shorter smoking cessation span was directly associated with a higher risk for peri-implantitis.

CLINICAL RELEVANCE

Educational and preventive strategies in general health services must attempt to reduce the adverse effects of cumulative smoking exposure and to explore the beneficial effects of smoking cessation on peri-implant status.

Association between soluble forms of the receptor for advanced glycation end products and periodontal disease: a retrospective study

Objectives

Periodontitis is the most common chronic disease that causes tooth loss and is related to systemic diseases such as cardiovascular disease and diabetes. An objective indicator of the current activity of periodontitis is necessary. Soluble forms of the receptor for advanced glycation end products (sRAGE) are markers that reflect the status of inflammatory diseases. In this study, the relationship between sRAGE and periodontitis was analyzed to determine whether it can be used to diagnose the current state of periodontitis.

Patients and Methods Eighty-four patients without any systemic diseases were diagnosed with periodontitis using three classifications of periodontitis. Demographics and oral examination data such as plaque index (PI), bleeding on probing (BOP) index, and probing pocket depth (PPD) were analyzed according to each classification. In addition, correlation and partial correlation between sRAGE and the values indicating periodontitis were analyzed.

Results

In each classification, the level of sRAGE tended to decrease if periodontitis was present or severe, but this change was not statistically significant. sRAGE and periodontitis-related variables exhibited a weak correlation, among which the BOP index showed a relatively strong negative correlation (ρ=–0.20). Based on this, on analyzing the correlation between the BOP index and sRAGE in the group with more severe periodontitis (PPD≥5 mm group, severe group of AAP/CDC [American Academy of Periodontology/Centers for Disease Control and Prevention], periodontitis group of López), the correlation further increased (ρ=–0.23, –0.40, –0.50). Partial correlation analysis of the sRAGE and BOP index showed a stronger negative correlation (ρ=–0.36, –0.55, –0.45).

Conclusion

sRAGE demonstrated a tendency to decrease upon increased severity of periodontitis according to the classifications used. Above all, the correlation with the BOP index, which reflects the current state of periodontitis, was higher in the group with severe periodontitis. This indicates that the current status of periodontitis can be diagnosed through sRAGE.

Tobacco Use and Periodontal Disease-The Role of Microvascular Dysfunction

Periodontal disease consists in highly prevalent wide-ranging inflammatory conditions that affect the supporting apparatus of teeth. Tobacco use is the most important risk factor for periodontal disease as it increases disease severity and periodontal surgery complications. Tobacco use is harmful for the vasculature by causing microvascular dysfunction, which is known to negatively affect periodontal disease. To the author's knowledge this paper is the first comprehensive review on the mechanisms by which tobacco use affects oral microcirculation and impacts the pathophysiology of periodontal disease. In healthy subjects, acute nicotine administration or tobacco use (smoking/smokeless forms) increases the blood flow in the oral mucosa due to local irritation and increased blood pressure, which overcome neural- and endocrine-mediated vasoconstriction. Chronic tobacco smokers display an increased gingival microvascular density, which is attributed to an increased capillary recruitment, however, these microcirculatory units show higher tortuosity and lower caliber. These morphological changes, together with the repetitive vasoconstrictive insults, contribute to lower gingival perfusion in chronic smokers and do not completely regress upon smoking cessation. In periodontal disease there is considerable gingival inflammation and angiogenesis in non-smokers which, in chronic smokers, are considerably suppressed, in part due to local immune suppression and oxidative stress. Tobacco exposure, irrespective of the form of use, causes long-term microvascular dysfunction that increases the risk of complications due to the natural disease course or secondary therapeutic strategies.

Electronic Cigarettes and Oral Health

Novel nicotine products, particularly electronic cigarettes (e-cigarettes), have become increasingly popular over the past decade. E-cigarettes are sometimes regarded as a less harmful alternative to tobacco smoking, and there is some evidence of their potential role as a smoking cessation aid. However, there are concerns about their health consequences, particularly in users who are not tobacco smokers, and also when used long term. Given the mode of delivery of these products, there is potential for oral health consequences. Over the past few years, there have been an increasing number of studies conducted to explore their oral health effects. In vitro studies have reported a range of cellular effects, but these are much less pronounced than those resulting from exposure to tobacco smoke. Microbiological studies have indicated that e-cigarette users have a distinct microbiome, and there is some indication this may be more pathogenic compared to nonusers. Evidence of oral health effects from clinical trials is still limited, and most studies to date have been small in scale and usually cross-sectional in design. Epidemiological studies highlight concerns over oral dryness, irritation, and gingival diseases. Interpreting data from e-cigarette studies is challenging, given the different populations that have been investigated and the continual emergence of new products. Overall, studies reveal potential oral health harms, underscoring the importance of efforts to reduce use in nonsmokers. However, in smokers who are using e-cigarettes as an aid to help them quit, the benefits of quitting tobacco smoking may outweigh any negative oral health impacts of e-cigarette use, particularly in the short term. Future research is needed to understand the clinical significance of some of the biological changes observed by following different cohorts of users longitudinally in carefully designed clinical studies and pragmatic trials supported by high-quality in vitro studies.

Effect of Switching to the Tobacco Heating System Versus Continued Cigarette Smoking on Chronic Generalized Periodontitis Treatment Outcome: Protocol for a Randomized Controlled Multicenter Study

BACKGROUND

Smoking is a significant risk factor for periodontal disease and tooth loss, as shown in several clinical studies comparing smokers and nonsmokers. Although only a few longitudinal studies have assessed the outcome of periodontal disease after smoking cessation, they indicated that recovery after nonsurgical treatment was more successful in those who had quit smoking. As part of tobacco harm reduction strategies, substituting cigarettes with alternative, less harmful tobacco products is an approach complementary to cessation for smokers who would otherwise continue to smoke. The Tobacco Heating System (THS), developed by Philip Morris International (commercialized as IQOS), is part of the heat-not-burn product category. The IQOS device electrically heats tobacco instead of burning it, at much lower temperatures than cigarettes, thereby producing substantially lower levels of harmful and potentially harmful constituents, while providing the nicotine, taste, ritual, and a sensory experience that closely parallel those of cigarettes. Phillip Morris International has published the results from a broad clinical assessment program, which was established to scientifically substantiate the harm reduction potential of the THS among adult healthy smokers switching to the THS. The program is now progressing toward including adult smokers with smoking-related diseases.

OBJECTIVE

The goal of this study is to demonstrate favorable changes of periodontal endpoints in response to mechanical periodontal therapy in patients with generalized chronic periodontitis who completely switched to THS use compared with continued cigarette smoking.

METHODS

This is a randomized controlled two-arm parallel-group multicenter Japanese study conducted in patients with chronic generalized periodontitis who switch from cigarettes to THS compared with smokers continuing to smoke cigarettes for 6 months. The patients were treated with mechanical periodontal therapy as per standard of care in Japan. The primary objective of the study is to demonstrate the beneficial effect of switching to THS use compared with continued cigarette smoking on pocket depth (PD) reduction in all sites with an initial PD≥4 mm. The secondary objectives include evaluation of other periodontal parameters (eg, clinical attachment level or gingival inflammation) and overall oral health status upon switching to THS. Safety was monitored throughout the study.

RESULTS

In total, 172 subjects were randomized to the cigarette (n=86) or THS (n=86) groups, and all 172 completed the study. The conduct phase of the study is completed, while data cleaning and analyses are ongoing.

CONCLUSIONS

This study is the first to test a heat-not-burn tobacco product in smokers with an already established disease. The results should further strengthen the evidence that switching to THS can significantly reduce the risk of smoking-related diseases if favorable changes in the evolution of chronic generalized periodontitis after mechanical therapy are found when compared with continued cigarette smoking.

TRIAL REGISTRATION

ClinicalTrials.gov NCT03364751; https://clinicaltrials.gov/ct2/show/NCT03364751.

INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID)

DERR1-10.2196/15350.

Bactericidal and clinical efficacy of photochemotherapy in acute necrotizing ulcerative gingivitis

AIM

This study was designed to investigate the clinical and microbiological parameters with photochemotherapy (PCT) against conventional debridement (CD) among patients with necrotizing ulcerative gingivitis (NUG).

MATERIALS AND METHODS

Patients with a diagnosis of NUG were divided into two groups: 'Group-PCT' that underwent indocyanine green-mediated PCT with adjunctive mechanical debridement, and Group-CD that underwent mechanical debridement with adjunctive 3 % hydrogen peroxide/chlorhexidine rinse. Clinical inflammatory gingival parameters including full-mouth plaque scores (FMPS), bleeding scores (FMBS), and probing depth (PD) were measured. Counts of Treponema microdentium, Fusobacterium nucleatum and Prevotella intermedia were assessed using polymerase chain reaction technique. All assessments were done at baseline, 3 weeks and 6 weeks.

RESULTS

Twenty-six participants were contacted and agreed to participate in the trial. The mean age of participants in group-PCT was 24.5 years while the mean age of patients in group-CD was 26.7 years. FMPS showed significant but equal reduction in both the groups at 3 weeks and 6 weeks (p < 0.01). The reduction in mean FMBS was higher in the group-PCT at 6 weeks follow-up (p < 0.05). All bacterial levels reduced from baseline to follow-up with both PCT and CD groups (p < 0.05). Group-PCT showed significantly reduced counts of T. microdentium and F. nucleatum at 3 weeks and 6 weeks compared with group-CD (p = 0.024). Equal reduction was shown for P. intermedia between both the groups at 3 and 6 weeks, respectively.

CONCLUSION

Application of adjunctive photochemotherapy was both clinically and microbiologically effective in the treatment of NUG.

Electronic Nicotine Delivery Systems (ENDS) and Their Relevance in Oral Health

The number and popularity of electronic nicotine delivery systems (ENDS) and especially e-cigarettes (e-cigs) have been increasing in the last decade. Although ENDS owe their popularity to excluding the harmful chemicals that are present in tobacco smoke, there is a debate whether they are safe, regulated, and as harmless as they are assumed to be and have potential unknown long-term effects. Involvement of cigarette smoking to the progression of periodontal diseases, other adverse oral health outcomes, and its detrimental effects to oral health are well-described. ENDS producer companies claim that these products can improve oral health by providing alternatives to smoking. However, the effect of e-cigs on oral health is not fully understood and is still debated among many scientists and clinicians. The number of studies addressing the potential toxic effect of ENDS or e-cig aerosol on oral cells is limited along with the clinical studies which are still preliminary, and their sample size is limited. The long-term effects of inhaled aerosols and the potential synergistic effect of the e-cigs components are not known. It is essential and of utmost importance to determine whether exposure to ENDS aerosol contributes to the progression of periodontal diseases and how it affects periodontal ligament and gingival cells which are believed to be its first targets. This review briefly summarizes the available evidence about the effects of e-cigs on periodontal health including several pathophysiological events, such as oxidative stress, DNA damage, inflammation, cellular senescence, dysregulated repair, and periodontal diseases.

Plaque-induced gingivitis: Case definition and diagnostic considerations

OBJECTIVE

Clinical gingival inflammation is a well-defined site-specific condition for which several measurement systems have been proposed and validated, and epidemiological studies consistently indicate its high prevalence globally. However, it is clear that defining and grading a gingival inflammatory condition at a site level (i.e. a "gingivitis site") is completely different from defining and grading a "gingivitis case" (GC) (i.e. a patient affected by gingivitis), and that a "gingivitis site" does not necessarily mean a "GC". The purpose of the present review is to summarize the evidence on clinical, biochemical, microbiologic, genetic markers as well as symptoms associated with plaque-induced gingivitis and to propose a set of criteria to define GC.

IMPORTANCE

A universally accepted case definition for gingivitis would provide the necessary information to enable oral health professionals to assess the effectiveness of their prevention strategies and treatment regimens; help set priorities for therapeutic actions/programs by health care providers; and undertake surveillance.

FINDINGS

Based on available methods to assess gingival inflammation, GC could be simply, objectively and accurately identified and graded using bleeding on probing score (BOP%) CONCLUSIONS: A patient with intact periodontium would be diagnosed as a GC according to a BOP score ≥ 10%, further classified as localized (BOP score ≥ 10% and ≤30%) or generalized (BOP score > 30%). The proposed classification may also apply to patients with a reduced periodontium, where a GC would characterize a patient with attachment loss and BOP score ≥ 10%, but without BOP in any site probing ≥4 mm in depth.

Clinical efficacy of photodynamic therapy in the treatment of necrotizing ulcerative periodontitis among HIV seropositive patients: A randomized controlled clinical trial

AIM

To evaluate clinical periodontal and microbiological parameters after the treatment with adjunctive antimicrobial photodynamic therapy (APDT) among HIV seropositive and seronegative patients with necrotizing ulcerative periodontitis (NUP).

MATERIALS AND METHODS

Seropositive patients (Group-I) and health controls (Group-II) with NUP were randomized into two groups and further underwent APDT and scaling and root planing (SRP), respectively. Clinical periodontal parameters including full mouth plaque index (FMPI), bleeding on probing (FMBOP), probing depth (PD) and clinical attachment level (CAL) gain were assessed. Levels of bacteria including Aggregatibacter actinomycetemcomitans (Aa), Porphyromonas gingivalis (Pg) and Tannerella forsythia (Tf) were assessed using PCR technique. All assessments were done at baseline, 3 months and 6 months.

RESULTS

All periodontal parameters including FMPI, FMBOP, PD and CAL significantly improved in both HIV seropositive and seronegative patients. The reduction in mean PD was higher only with the APDT treatment among group II patients compared to group I patients at follow-up (p < 0.05). The gain in mean CAL was higher only with the APDT treatment among group I and group II patients at follow-up (p < 0.05). All bacterial levels reduced from baseline to follow-up with both APDT and SRP treatments in both groups (p < 0.05). APDT showed significantly reduced counts of Aa and Tf at 3 months, and only Aa at 6 months among HIV seropositive patients, while the levels of Pg and Tf significantly reduced at 3 months and only Aa at 6 months in the seronegative patients, respectively (p < 0.05).

CONCLUSION

Application of antimicrobial photodynamic therapy as an adjunct to scaling and root planing was effective in improving clinical periodontal parameters and bacterial levels among HIV positive patients with NUP. However, the improvement was not greater when compared with HIV seronegative patients.

Tobacco-use patterns and self-reported oral health outcomes: A cross-sectional assessment of the Population Assessment of Tobacco and Health study, 2013-2014

BACKGROUND

Few studies consider simultaneously the oral health implications of nontraditional tobacco products and tobacco-use patterns. The authors aimed to evaluate self-reported gingival disease among cigarette smokers and users of other types of tobacco products.

METHODS

The authors used survey-weighted multivariable logistic regression to assess associations between different tobacco products, use patterns (for example, dual or multiple tobacco product use or product switching); and lifetime history of gingival disease diagnosis and treatment. They used the nationally representative (US) Population Assessment of Tobacco and Health study's Wave 1 (2013-2014) adult data (N = 32,320).

RESULTS

Overall, 12.1% of participants self-reported gingival disease diagnosis, and 19.1% reported receiving treatment. Groups with the highest adjusted relative odds for diagnosis (reference, lifetime tobacco never users) were pipe users (2.7; 95% confidence interval [CI], 1.3 to 5.3), e-cigarette users (2.9; 95% CI, 1.9 to 4.5), multiple tobacco product users (2.8; 95% CI, 2.4 to 3.4), and recent (< 12 months) quitters (2.8; 95% CI, 2.0 to 3.8). Similarly, odds of treatment report were highest among pipe users (2.3; 95% CI, 1.3 to 4.1), e-cigarette users (2.3; 95% CI, 1.3 to 4.1), multiple tobacco product users (1.6; 95% CI, 1.4 to 1.9), and recent quitters (1.7; 95% CI, 1.3 to 2.2).

CONCLUSIONS

Numerous tobacco-use patterns were associated with worse periodontal health compared with tobacco never users. These findings are consistent with previous biological and epidemiologic evidence linking tobacco use to poor periodontal health.

PRACTICAL IMPLICATIONS

Dental clinicians should anticipate various tobacco-use patterns among their patients, all of which may impact oral health. Oral health care professionals should remain informed of, screen for, and address the use of all tobacco products in practice.

Tobacco-induced suppression of the vascular response to dental plaque

Cigarette smoking presents oral health professionals with a clinical and research conundrum: reduced periodontal vascular responsiveness to the oral biofilm accompanied by increased susceptibility to destructive periodontal diseases. This presents a significant problem, hampering diagnosis and complicating treatment planning. The aim of this review is to summarize contemporary hypotheses that help to explain mechanistically the phenomenon of a suppressed bleeding response to dysbiotic plaque in the periodontia of smokers. The influence of smoke exposure on angiogenesis, innate cell function, the production of inflammatory mediators including cytokines and proteases, tobacco-bacteria interactions, and potential genetic predisposition are discussed.

A pilot study of the gingival response when smokers switch from smoking to vaping

Introduction Tobacco smoking is one of the most important risk factors for periodontitis as it alters the host response to plaque. Although the prevalence of tobacco smoking has declined in recent years, the use of electronic-cigarettes (vaping) has increased. The effect of vaping on the gingiva is unknown and an evidence-base needs to be established before providing dental advice about the use of these products.Objective To compare the gingival health of a group of established smokers before and after substituting vaping for smoking tobacco.Design Pilot.Setting Guy's Dental Hospital (England) from April-December 2015.Materials and methods Twenty established smokers (all staff members at Guy's Hospital) with mild periodontal disease replaced their regular smoking habits with the use of e-cigarettes for two weeks.Main outcome measure The primary outcome measure of gingival inflammation was bleeding on probing. Levels of selected pro-inflammatory cytokines in GCF, saliva and serum samples were also determined.Results and conclusions There was a statistically significant increase in gingival inflammation when tobacco smokers switched from smoking to vaping for two weeks. However, this result must be interpreted with extreme caution since this is only a pilot study. Nonetheless, this study should provide a stepping stone to encourage further investigation of the effects of vaping on periodontal health.

A controlled clinical study of periodontal health in anticoagulated patients: Assessment of bleeding on probing

Background

According to the Spanish Society of Cardiology, 700,000 patients receive oral anticoagulants, and in these cases bleeding on probing (BOP) could be altered. However, no studies have analyzed the periodontal status of these patients and the effects anticoagulants may have upon BOP. A study was made of the possible relationship between plaque index, probing depth, INR (International Normalized Ratio) and acenocoumarol dose versus the clinical signs of BOP in a sample of anticoagulated patients. Likewise, an analysis was made of oral hygiene habits and attitude towards bleeding in these patients.

Material and Methods

A controlled observational clinical study was made in La Ribera Hospital (Valencia, Spain) involving 44 anticoagulated patients treated with Sintrom® (acenocoumarol) and a homogeneous control group of 44 non-anticoagulated patients. A survey on oral hygiene habits and attitude towards bleeding was carried out, and the main periodontal parameters were recorded.

Results

Probing depth was the parameter with the strongest correlation to BOP (p<0.001), followed by the plaque index (p<0.002). In contrast, no relationship was observed between acenocoumarol dose or INR and BOP. Mean BOP was greater in the control group than in the anticoagulated group (p<0.001). Oral hygiene habits and attitude towards bleeding differed significantly between groups.

Conclusions

We have found no explanation why BOP was greater in the control group. What seems clear is that in the presence of the same plaque index and probing depth, anticoagulated patients did not bleed more than non-anticoagulated patients. A lack of knowledge of health and oral hygiene habits was observed in these subjects. Key words:Anticoagulant therapy, bleeding on probing, periodontal health.

Cumulative survival rate and associated risk factors of Implantium implants: A 10-year retrospective clinical study

PURPOSE

The objective of this study was to determine the cumulative survival rate (CSR) and associated risk factors of Implantium implants by retrospective clinical study.

MATERIALS AND METHODS

Patients who received Implantium implants (Dentium Co., Seoul, Korea) at Korea University Guro Hospital from 2004 to 2011 were included. The period between the first surgery and the last hospital visit until December 2015 was set as the observation period for this study. Clinical and radiographic data were collected from patient records, including all complications observed during the follow-up period. Kaplan-Meier analysis was performed to examine CSR. Multiple Cox proportional hazard model was employed to assess the associations between potential risk factors and CSR.

RESULTS

A total of 370 implants were placed in 121 patients (mean age, 56.1 years; range, 19 to 75 years). Of the 370 implants, 13 failed, including 7 implants that were lost before loading. The 10-year cumulative survival rate of implants was 94.8%. The multiple Cox proportional hazard model revealed that significant risk factor of implant failure were smoking and maxillary implant (P<.05).

CONCLUSION

The 10-year CSR of Implantium implants was 94.8%. Risk factors of implant failure were smoking and maxillary implant.

Validity of Self-Reported Periodontal Disease: A Systematic Review and Meta-Analysis

BACKGROUND

Periodontal disease (PdD) has been shown to be related to other systemic diseases. However, to assess this relationship, large epidemiologic studies are required. Such studies need validated self-report measures. The aim of this systematic review is to assess the validity of self-reported measures in the diagnosis of PdD.

METHODS

The review followed Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Medline, Embase, and Google Scholar were searched up to January 2016. Two periodontal journals were searched manually. Two reviewers independently made selected studies and extracted data. All disagreements were resolved after discussion with a third reviewer. Risk of bias was evaluated. Sensitivity, specificity, diagnostic odds ratio, and 95% confidence interval (CI) were calculated. Of 933 papers found, 11 were selected for the review. All studies, except two, had acceptable quality. Four comparable studies were selected for meta-analysis.

RESULTS

Study size ranged from 114 to 1,426 participants. Sensitivity and specificity ranged from 4% to 93% and 58% to 94%, respectively. Diagnostic odds ratio was 1.4 (95% CI: 0.9 to 2.2) for the question on bleeding gums and 11.7 (95% CI: 4.1 to 33.4) for the question on tooth mobility. Heterogeneity was low for most questions except those on painful gums and tooth mobility.

CONCLUSIONS

Self-reported PdD has acceptable validity and can be used for surveillance of PdD in large epidemiologic studies. However, there is a need for large, well-designed diagnostic studies.

Smoking and gingivitis: focus on inducible nitric oxide synthase, nitric oxide and basic fibroblast growth factor

BACKGROUND

Periodontal disease pathogenesis has been associated with smoking. Gingivitis is a mild and reversible form of periodontal disease and it tends to progress to periodontitis only in susceptible individuals. In the present study, we aimed to examine the impact of smoking on host responses in gingivitis and to evaluate and compare the inducible nitric oxide synthase (iNOS) activity in gingival tissue and NO and basic fibroblast growth factor (bFGF) levels in the gingival crevicular fluid of patients with gingivitis and healthy individuals.

MATERIAL AND METHODS

Forty-one participants were assigned to the gingivitis-smoker (n = 13), gingivitis (n = 13), healthy-smoker (n = 7) and healthy groups (n = 8). Clinical indices were recorded; gingival biopsy and gingival crevicular fluid samples were obtained from papillary regions. iNOS expression was evaluated by immunohistochemical staining. The immunoreactive cells were semiquantitatively assessed. For the quantitative determination of nitrite and nitrate in gingival crevicular fluid, the NO assay kit was used. The amount of bFGF in gingival crevicular fluid was determined by enzyme-linked immunosorbent assay.

RESULTS

The gingivitis-smoker group demonstrated a stronger iNOS expression than the non-smoker gingivitis group. iNOS expression intensity was lower in the non-smoker healthy group compared to that in healthy-smokers. No significant gingival crevicular fluid NO and bFGF level changes were observed between groups. Among patients with gingivitis, a positive correlation was detected between gingival crevicular fluid NO and bFGF levels (r = 0.806, p = 0.001).

CONCLUSIONS

Our data suggest that smoking has significant effects on iNOS expression but not on gingival crevicular fluid NO or bFGF levels in healthy and patients with gingivitis. However, our results suggest that bFGF might be involved in the regulation of NO production via iNOS.

History of periodontal disease diagnosis and lung cancer incidence in the Women's Health Initiative Observational Study

PURPOSE

While some evidence suggests that periodontal disease (PD) might be positively associated with lung cancer, prospective studies in women are limited. Previous findings may reflect residual confounding by smoking. The study aims to determine whether history of PD diagnosis is associated with incident lung cancer in a large cohort of postmenopausal women.

METHODS

Prospective analyses were conducted in a cohort of 77,485 postmenopausal women enrolled in the Women's Health Initiative Observational Study. History of PD (prevalence of 26.1 %) was self-reported, and 754 incident lung cancer cases occurred during an average 6.8 (SD ± 2.6) years of follow-up. Cox proportional hazards regression analysis was used to estimate hazard ratios (HRs) and 95 % confidence intervals (CIs).

RESULTS

Overall, PD was positively associated with lung cancer risk after adjusting for detailed smoking history including smoking status and pack-years of smoking (HR 1.24, 95 % CI 1.07-1.45). There was a positive additive interaction between PD with pack-years of smoking (p = 0.02), suggesting a potential synergistic effect between PD and smoking intensity on lung cancer. The association between PD and lung cancer was stronger in former smokers. When restricted to never-smokers, PD was not associated with lung cancer (HR 1.02, 95 % CI 0.68-1.53).

CONCLUSIONS

Periodontal disease was not independently associated with lung cancer in non-smoking postmenopausal women. However, smoking and PD jointly increased lung cancer risk beyond that expected from the sum of the each effect separately. The potential synergism between PD and smoking on lung cancer warrants further examination.

Altered antigenic profiling and infectivity of Porphyromonas gingivalis in smokers and non-smokers with periodontitis

BACKGROUND

Cigarette smokers are more susceptible to periodontal diseases and are more likely to be infected with Porphyromonas gingivalis than non-smokers. Furthermore, smoking is known to alter the expression of P. gingivalis surface components and compromise immunoglobulin (Ig)G generation. The aim of this study is to evaluate whether the overall IgG response to P. gingivalis is suppressed in smokers in vivo and whether previously established in vitro tobacco-induced phenotypic P. gingivalis changes would be reflected in vivo.

METHODS

The authors examined the humoral response to several P. gingivalis strains as well as specific tobacco-regulated outer membrane proteins (FimA and RagB) by enzyme-linked immunosorbent assay in biochemically validated (salivary cotinine) smokers and non-smokers with chronic periodontitis (CP: n = 13) or aggressive periodontitis (AgP: n = 20). The local and systemic presence of P. gingivalis DNA was also monitored by polymerase chain reaction.

RESULTS

Smoking was associated with decreased total IgG responses against clinical (10512, 5607, and 10208C; all P <0.05) but not laboratory (ATCC 33277, W83) P. gingivalis strains. Smoking did not influence IgG produced against specific cell-surface proteins, although a non-significant pattern toward increased total FimA-specific IgG in patients with CP, but not AgP, was observed. Seropositive smokers were more likely to be infected orally and systemically with P. gingivalis (P <0.001), as determined by 16S RNA analysis.

CONCLUSION

Smoking alters the humoral response against P. gingivalis and may increase P. gingivalis infectivity, strengthening the evidence that mechanisms of periodontal disease progression in smokers may differ from those of non-smokers with the same disease classification.

Periodontal disease, atherosclerosis, adverse pregnancy outcomes, and head-and-neck cancer

Interrelationships between periodontal infection and systemic conditions such as cardiovascular disease, adverse pregnancy outcomes, and head-and-neck cancer have become increasingly appreciated in recent years. Periodontitis is associated with cardiovascular disease (CVD) and, experimentally, with measures of atherosclerosis and endothelial dysfunction. Periodontal therapy may reduce atherosclerotic changes and improve endothelial function. Preliminary findings suggest a role for the genetic locus ANRIL in the pathobiology of both CVD and periodontitis. Periodontal pathogens induce anticardiolipin in periodontitis patients by molecular mimicry of the serum protein β-2 glycoprotein I. These antibodies have biological and pathological activities consistent with those reported for other infection-induced antiphospholipid antibodies. Anticardiolipin may explain some of the observed associations between periodontitis and systemic conditions such as CVD and adverse pregnancy outcomes. The oral commensal Fusobacterium nucleatum (Fn) becomes pathogenic on migration to extra-oral sites. Fn infection of the fetal-placental unit has been linked to pregnancy complications, including preterm birth, stillbirth, and early-onset neonatal sepsis. Reagents aimed at inhibiting or resolving inflammatory responses may be used to treat or prevent pregnancy complications due to bacterial infection. Chronic periodontitis may be independently associated with head-and-neck squamous cell carcinoma (HNSCC) through direct toxic effects of bacteria and their products, and/or through indirect effects of inflammation. Additionally, chronic periodontitis may facilitate the acquisition and persistence of oral HPV infection, a recently emerged risk factor for HNSCC.

The role of smoking and gingival crevicular fluid markers on coronally advanced flap outcomes

BACKGROUND

This study evaluates possible effects of smoking on the following: 1) biochemical content in gingival crevicular fluid (GCF) samples from sites of gingival recession and saliva; and 2) clinical outcomes of coronally advanced flap (CAF) for root coverage.

METHODS

Eighteen defects in 15 patients were included in each of the smoker and non-smoker groups. Baseline cotinine, basic fibroblast growth factor, vascular endothelial growth factor, platelet-derived growth factor, interleukin (IL)-8, IL-10, IL-12, tumor necrosis factor-α, matrix metalloproteinase (MMP)-8, MMP-9, and plasminogen activator inhibitor-1 levels were determined in GCF and saliva samples. CAF with microsurgery technique was applied. Plaque index, papilla bleeding index, recession depth (RD), recession width (RW), and root surface area were evaluated at baseline and postoperative months 1, 3, and 6. Probing depth, clinical attachment level (CAL), and keratinized gingival width (KGW) was recorded at baseline and month 6. Percentage of root coverage and complete root coverage were calculated at postoperative months 1, 3, and 6.

RESULTS

All biochemical parameters were similar in the two groups apart from the definite difference in salivary cotinine concentrations (P = 0.000). Compared with the baseline values, RD, RW, CAL, and root surface area decreased, and KGW increased, with no significant difference between the study groups. CAL gain, percentage of root coverage, and complete root-coverage rates were similar in the study groups.

CONCLUSION

Similar baseline biochemical data and comparably high success rates of root coverage with CAF in systemically and periodontally healthy smokers versus non-smokers suggest lack of adverse effects of smoking on clinical outcomes.

Is there a positive effect of smoking cessation on periodontal health? A systematic review

BACKGROUND

Although the detrimental effects of tobacco on the periodontal tissues have been reported extensively, little is known about the potential beneficial effect of smoking cessation on periodontal health. The aim of this systematic review is to evaluate the effect of smoking cessation on periodontitis progression and response to periodontal therapy.

METHODS

Two independent reviewers completed the review process through title (n = 118), abstract (n = 24), and whole-paper selection (n = 5). Sources include Medline and EMBASE databases (up to December 2012) and a reference list of selected studies. Prospective studies comparing progression rates of periodontitis between smokers and quitters and clinical trials evaluating the effect of smoking-cessation programs, alone or in combination with periodontal treatment, were included. At least 1 year of follow-up was required for inclusion.

RESULTS

Of 331 potentially relevant publications, five studies fulfilled the inclusion criteria. Because of heterogeneity of the studies, a meta-analysis could not be performed. One study reported that the progression of clinical attachment loss (AL) ≥3 mm during a 6-year period was approximately three times higher among smokers than quitters (P <0.001). Two studies (10 and 20 years of follow-up) observed a decrease in radiographic bone loss of ≈30% among quitters when compared with smokers. Among individuals receiving non-surgical periodontal treatment, quitters were more likely to have periodontal probing depth reductions (P <0.05) than non-quitters/oscillators. No differences in AL were observed.

CONCLUSION

Based on the limited available evidence, smoking cessation seems to have a positive influence on periodontitis occurrence and periodontal healing.

Smoking and periodontal tissues: a review

The impact of smoking on general health has been widely studied and is directly related to several important medical problems including cancer, low birth weight, and pulmonary and cardiovascular disease. In the past 25 years, there has also been an increasing awareness of the role of cigarette consumption in oral health problems such as periodontal disease. Smoking is considered the major risk factor in the prevalence, extent and severity of periodontal diseases. This article will discuss the available evidence and provide the reader with an overview of the impact of smoking and its cessation on the pathogenesis and treatment of periodontal diseases.

Fatty acid profiles in smokers with chronic periodontitis

We hypothesized that tobacco smoke induces alterations to the 3-OH fatty acids present in lipid A in a manner consistent with a microflora of reduced inflammatory potential. Whole saliva samples and full-mouth clinical periodontal recordings were obtained from persons with (22 smokers; 15 non-smokers) and without (14 smokers; 15 non-smokers) chronic periodontitis. Clear differences in the contributions of multiple saturated 3-OH fatty acid species were noted in the group with disease compared with healthy individuals. Increases in the long-chain fatty acids associated with anaerobic bacterial periodontopathogens, particularly 3-OH-C(i17.0) (146.7%, relative to controls), were apparent. Significant reductions in the 3-OH fatty acids associated with the consensus (high potency) enteric LPS structure (3-OH-C(12.0) and 3-OH-C(14.0); 33.3% and 15.8% reduction, respectively) were noted in smokers compared with non-smokers with chronic periodontitis. Thus, smoking is associated with specific structural alterations to the lipid-A-derived 3-OH fatty acid profile in saliva that are consistent with an oral microflora of reduced inflammatory potential. These findings provide much-needed mechanistic insight into the established clinical conundrum of increased infection with periodontal pathogens but reduced clinical inflammation in smokers.

Tobacco upregulates P. gingivalis fimbrial proteins which induce TLR2 hyposensitivity

BACKGROUND

Tobacco smokers are more susceptible to periodontitis than non-smokers but exhibit reduced signs of clinical inflammation. The underlying mechanisms are unknown. We have previously shown that cigarette smoke extract (CSE) represents an environmental stress to which P. gingivalis adapts by altering the expression of several virulence factors - including major and minor fimbrial antigens (FimA and Mfa1, respectively) and capsule - concomitant with a reduced pro-inflammatory potential of intact P. gingivalis.

METHODOLOGY/PRINCIPAL FINDINGS

We hypothesized that CSE-regulation of capsule and fimbrial genes is reflected at the ultrastructural and functional levels, alters the nature of host-pathogen interactions, and contributes to the reduced pro- inflammatory potential of smoke exposed P. gingivalis. CSE induced ultrastructural alterations were determined by electron microscopy, confirmed by Western blot and physiological consequences studied in open-flow biofilms. Inflammatory profiling of specific CSE-dysregulated proteins, rFimA and rMfa1, was determined by quantifying cytokine induction in primary human innate and OBA-9 cells. CSE up-regulates P. gingivalis FimA at the protein level, suppresses the production of capsular polysaccharides at the ultrastructural level, and creates conditions that promote biofilm formation. We further show that while FimA is recognized by TLR2/6, it has only minimal inflammatory activity in several cell types. Furthermore, FimA stimulation chronically abrogates the pro-inflammatory response to subsequent TLR2 stimulation by other TLR-2-specific agonists (Pam3CSK4, FSL, Mfa1) in an IkappaBalpha- and IRAK-1-dependent manner.

CONCLUSIONS/SIGNIFICANCE

These studies provide some of the first information to explain, mechanistically, how tobacco smoke changes the P. gingivalis phenotype in a manner likely to promote P. gingivalis colonization and infection while simultaneously reducing the host response to this major mucosal pathogen.

Chronic periodontitis and the incidence of head and neck squamous cell carcinoma

Substantial evidence supports an association between chronic infections/inflammation, and cancer. The aim of this study was to assess the effect of chronic periodontitis on head and neck squamous cell carcinoma (HNSCC). The study population consisted of new patients at the Department of Dentistry and Maxillofacial Prosthetics, Roswell Park Cancer Institute between 1999 and 2005. Cases were patients diagnosed with primary HNSCC. Controls were all patients seen during the same time period but negative for malignancy. Patients age <21 years, edentulous, immunocompromised, and those with history of cancer were excluded. Periodontitis was measured by alveolar bone loss (ABL) from panoramic radiographs by one examiner blind to cancer status. A total of 473 patients (266 cases and 207 controls) were included in the study. Each millimeter of ABL was associated with >4-fold increased risk of HNSCC (odds ratio, 4.36; 95% confidence interval, 3.16-6.01) after adjustment for age, gender, race/ethnicity, marital status, smoking status, alcohol use, and missing teeth. The strength of the association was greatest in the oral cavity, followed by oropharynx and larynx. The association persisted in subjects who never used tobacco and alcohol. There was a significant interaction between smoking and ABL (P = 0.03). Patients with periodontitis were more likely to have poorly differentiated oral cavity SCC than those without periodontitis (32.8% versus 11.5%; P = 0.038). This study suggests that chronic periodontitis is an independent risk factor for HNSCC and smoking modifies this association. These results have implications for practical and safe strategies for prevention, diagnosis, and treatment of HNSCC.

Tobacco-induced alterations to Porphyromonas gingivalis-host interactions

Smokers are more susceptible than non-smokers to persistent infection by Porphyromonas gingivalis, a causative agent of periodontitis. Patients who smoke exhibit increased susceptibility to periodontitis and are more likely to display severe disease and be refractory to treatment. Paradoxically, smokers demonstrate reduced clinical inflammation. We show that P. gingivalis cells exposed to cigarette smoke extract (CSE) induce a lower proinflammatory response (tumour necrosis factor-alpha, interleukin-6, interleukin-12 p40) from monocytes and peripheral blood mononuclear cells than do unexposed bacteria. This effect is reversed when CSE-exposed bacteria are subcultured in fresh medium without CSE. Using microarrays representative of the P. gingivalis genome, CSE-exposure resulted in differential regulation of 6.8% of P. gingivalis genes, including detoxification and oxidative stress-related genes; DNA repair genes; and multiple genes related to P. gingivalis virulence, including genes in the major fimbrial and capsular operons. Exposure to CSE also altered the expression of outer membrane proteins, most notably by inducing the virulence factors RagA and RagB, and a putative lipoprotein cotranscribed with the minor fimbrial antigen. Therefore, CSE represents an environmental stress to which P. gingivalis adapts by altering gene expression and outer membrane proteins. These changes may explain, in part, the altered virulence and host-pathogen interactions that have been documented in vivo in smokers with periodontal disease.

Tobacco use increases susceptibility to bacterial infection

Active smokers and those exposed to secondhand smoke are at increased risk of bacterial infection. Tobacco smoke exposure increases susceptibility to respiratory tract infections, including tuberculosis, pneumonia and Legionnaires disease; bacterial vaginosis and sexually transmitted diseases, such as chlamydia and gonorrhoea; Helicobacter pylori infection; periodontitis; meningitis; otitis media; and post-surgical and nosocomial infections. Tobacco smoke compromises the anti-bacterial function of leukocytes, including neutrophils, monocytes, T cells and B cells, providing a mechanistic explanation for increased infection risk. Further epidemiological, clinical and mechanistic research into this important area is warranted.