Variations in the gingival polymorphonuclear leukocyte migration rate in dogs induced by chemotactic autologous serum and migration inhibitor from tobacco smoke

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.

Personalized periodontal treatment for the tobacco- and alcohol-using patient

The use of various forms of tobacco is one of the most important preventable risk factors for the incidence and progression of periodontal disease. Tobacco use negatively affects treatment outcomes for both periodontal diseases and conditions, and for dental implants. Tobacco-cessation programs can mitigate these adverse dental treatment outcomes and may be the most effective component of a personalized periodontal treatment approach. In addition, heavy alcohol consumption may exacerbate the adverse effects of tobacco use. In this review, the microbiology, host/inflammatory responses and genetic characteristics of the tobacco-using patient are presented as a framework to aid the practitioner in developing personalized treatment strategies for these patients. These personalized approaches can be used for patients who use a variety of tobacco products, including cigarettes, cigars, pipes, smokeless tobacco products, e-cigarettes and other tobacco forms, as well as patients who consume large amounts of alcohol. In addition, principles for developing personalized tobacco-cessation programs, using both traditional and newer motivational and pharmacological approaches, are presented.

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.

Smoking and inflammation: evidence for a synergistic role in chronic disease

Tobacco smoking is the most important preventable risk factor for periodontitis; however, the underlying biological mechanisms responsible for the detrimental effects of smoking on periodontal health remain largely unclear. It is also well established that smoking has a negative impact on several inflammatory diseases, including rheumatoid arthritis, multiple sclerosis and inflammatory bowel disease. The aim of this paper was to review smoking-related changes in local and systemic host responses with a focus on cellular and molecular effects that could explain a hyperinflammatory response leading to periodontal destruction. Biological mechanisms that may be common to periodontal disease and other chronic inflammatory diseases were also explored, together with gene-smoking interactions. An epidemiologic perspective on the burden of smoking on periodontal health and the potential for smoking cessation is also presented. Tobacco smoking seems to induce changes ranging from decreased leukocyte chemotaxis to decreased production of immunoglobulins. Smoking also seems to cause a stronger inflammatory reaction with an increased release of potentially tissue-destructive substances (e.g. reactive oxygen species, collagenase, serine proteases and proinflammatory cytokines). These findings support a hypothesis that periodontitis is a hyperinflammatory condition rather than a hypo-inflammatory condition.

Comparative analysis of smoking influence on periodontal tissue in subjects with periodontal disease

THE AIM OF THE STUDY

The aim of the study was clinical and cytological examination of gingival changes in smokers and non-smokers. Further, specific goals of this study were health promotion in patient, particularly in smokers.

METHODS

The anamnesis was taken and clinical examination was conducted on the patients who came on Dental Clinic. During the clinical examination, plaque index (Pl)(16), gingival index Löe-Silness (Gi) and the community periodontal index of treatment needs (CPITN)(17) were done. After diagnosis was established, participants divided into group I -smokers, and group II - non-smokers. The gingival smears were taken for cytological analysis, dried on air, and stained by haematoxylin-eosin method.

RESULTS

The values of gingival index (GI)- Löe-Silness and periodontal index (CPITN) were higher in the group of smokers, but plaque index was also higher with statistically significant difference of their values between examined group, with maximum level of significance (p<0,001). The size of nucleus (area, Ferret's diameter and perimeter) was higher in the group of smokers, but differences were not statistically significant. In the group of non-smokers density of nucleus was higher than in non-smokers group, but difference was not statistically significant.

CONCLUSION

The values of examined indices showed higher values in smokers group. This finding could show that the level of oral hygiene is higher in the non smokers group. The size of nucleus (area, Ferret's diameter and perimeter) was higher in the group of smokers, but differences were not statistically significant. Teamwork of many different speciality experts is required for better periodontal health of smokers.

Periodontal status in smokers and nonsmokers: a clinical, microbiological, and histopathological study

A case-control study was done to assess the influence of smoking on clinical, microbiological, and histopathological parameters. Methods. Two hundred dentate male patients (100 smokers and 100 nonsmokers) ranging between 25 and 50 years were enrolled in the study. Periodontal parameters were recorded. Plaque samples were collected for microbial analysis for BANA test. Gingival biopsies were obtained from selected site for assessing histopathological changes. Results. Both groups showed almost similar plaque levels (P=0.258), but smokers had reduced gingival (0.62 ± 0.31) and bleeding indices (28.53 ± 17.52) and an increased calculus index (1.62 ± 0.36). Smokers had an increased probing depth of 4-7 mm (P=0.009) and overall increased CAL. No difference in microbiota was found between the two groups. Histopathologically smokers showed a decreased blood vessel density (8.84 ± 0.96) and inflammatory cells (52.00 ± 9.79). Conclusions. It is quite possible that many of the pathogenic mechanisms involved in tissue degradation in periodontitis in smokers could be quite different from those in nonsmokers.

Impact of smoking on inflammation: overview of molecular mechanisms

BACKGROUND

Inflammation is a critical component of normal tissue repair, as well as being fundamental to the body's defense against infection. Environmental factors, such as smoking, have been reported to modify the host response and hence modify inflammation progression, severity and outcome. Therefore, a comprehensive understanding of the molecular mechanisms by which smoking affects inflammation is vital for preventive and therapeutic strategies on a clinical level.

AIM

The purpose of the present article is to review the potential biological mechanisms by which smoking affects inflammation, emphasizing recent developments.

RESULTS

Smoking is reported to effect a number of biological mediators of inflammation through its effect on immune-inflammatory cells, leading to an immunosuppressant state. Recent evidence strongly suggests that the molecular mechanisms behind the modulation of inflammation by smoking mainly involve the nuclear factor-kappa B (NF-kB) family, through the activation of both an inhibitor of IkB kinase (IKK)-dependent and -independent pathway. In addition to NF-kB activation, a number of transcriptional factors including GATA, PAX5 and Smad 3/4, have also been implicated.

CONCLUSION

Multiple mechanisms may be responsible for the association of smoking and inflammation, and the identification of potential therapeutic targets should guide future research.

Tobacco as a risk factor for survival of dental implants

BACKGROUND

It has been shown that smoking habits represent an increased risk for impaired bone healing and implant failure. This study aimed to evaluate the implant survival rates among non-smokers (NS) and different kinds of smokers (S).

METHODS

A retrospective analysis was made over a 5-year period of the clinical and radiographic findings corresponding to 66 consecutive patients who had received a total of 165 dental implants. Patients were divided into two groups: S, 40 patients (95 implants; 58% of the sample); and NS, 26 patients (70 implants; 42% of the sample). Also, S and NS were classified into four different categories according to daily tobacco use: NS, 26 patients and 70 implants; light smokers (LS), 23 patients and 44 implants; moderate smokers (MS), 11 patients and 25 implants; and heavy smokers (HS), six patients and 26 implants.

RESULTS

Sixteen implants (9.7%) failed and had to be removed. Group S showed 15 failures and a success rate of 84.2%. Group NS had only one failure, giving a success rate of 98.6%. The risk of implant failure was approximately 31% in those who smoked more than 20 cigarettes per day. HS showed statistical differences from NS or LS. However, they did not show any differences from MS.

CONCLUSIONS

Within the limits of the present study, the use of tobacco involves a 15.8% risk of implant failure, with a 13.1 odds ratio. LS or MS tobacco use involves a 10.1% relative risk of implant loss, whereas the consumption of >20 cigarettes per day increases this risk to 30.8%.

Impact of smoking on the clinical, microbiological and immunological parameters of adult patients with periodontitis

OBJECTIVES

The aim of the current study was to assess the impact of smoking on the clinical indices, the humoral immune response and the detection frequency of putative periodontal pathogens in patients with periodontitis cross-sectionally and following therapy.

MATERIAL AND METHODS

Clinical measurements, subgingival plaque samples, gingival crevicular fluid (GCF) and sera were collected from 40 untreated patients with moderate-to-advanced chronic periodontitis before and after treatment over a period of 6 months. The treatment consisted of the initial therapy of scaling and root planing. Smoking status was self-reported and was confirmed by cotinine enzyme inhibition assay (CEIA). Whole-mouth clinical measurements were recorded with a manual periodontal probe at baseline (BAS) and at 6 months (RAS). Selected-site analyses were performed on the deepest site in each quadrant before and after therapy and clinical indices were recorded with an electronic pressure-sensitive probe. GCF sample volume was quantified using the Periotron 6000. Polymerase chain reaction (PCR) was utilized to determine the presence of Porphyromonas gingivalis, Actinobacillus actinomycetemcomitans, Prevotella intermedia, Treponema denticola and Tanerella forsythensis in subgingival plaque. Enzyme-linked immunosorbent assay examined the systemic antibody titres to these bacteria, and thiocyanate disassociation determined the antibody avidity to these organisms.

RESULTS

At baseline, smokers showed significantly less gingival inflammation and lower GCF volume compared with non-smokers. After treatment, a compromised clinical outcome was noted for smokers in terms of pocket depth reduction and gain in attachment levels. No significant differences in the detection of putative periodontal pathogens in subgingival plaque existed between smokers and non-smokers. A consistent trend was noted in that smokers had lower sera immunoglobulin G antibody titres to these organisms before and after treatment (statistically significant for A. actinomycetemcomitans). This pattern was less clear when antibody avidities were considered, revealing only small differences, if any, between the two groups of patients.

CONCLUSION

Current data indicate that smokers with periodontal disease have a suppressed inflammatory response, a significantly less favourable clinical outcome and seem to have an altered host antibody response to antigenic challenge than non-smokers. In contrast, the subgingival microflora of smokers appears similar to that of non-smokers.

Clinical and microbiological effect of scaling and root planing in smoker and non-smoker chronic and aggressive periodontitis patients

OBJECTIVES

To compare the effects of scaling and root planing (SRP) on clinical and microbiological parameters at selected sites in smoker and non-smoker chronic and generalized aggressive periodontitis patients.

MATERIALS AND METHODS

Clinical parameters including probing depth (PD), relative attachment level (RAL), and bleeding upon probing (BOP), and subgingival plaque samples were taken from four sites in 28 chronic periodontitis (CP) and 17 generalized aggressive periodontitis (GAgP) patients before and after SRP. Polymerase chain reaction assays were used to determine the presence of A. actinomycetemcomitans, Porphyromonas gingivalis, Tannerella forsythensis, Prevotella intermedia and Treponema denticola.

RESULTS

Both CP and GAgP non-smokers had significantly greater reduction in pocket depth (1.0+/-1.3 mm in CP smokers versus 1.7+/-1.4 mm in non-smokers, p=0.007 and 1.3+/-1.0 in GAgP smokers versus 2.4+/-1.2 mm in GAgP non-smokers, p<0.001) than respective non-smokers, with a significant decrease in Tannerella forsythensis in CP sites (smokers 25% increase and non-smokers 36.3% decrease, p<0.001) and Prevotella intermedia at GAgP sites (smokers 25% reduction versus 46.9% in non-smokers, p=0.028).

CONCLUSION

SRP was effective in reducing clinical parameters in both groups. The inferior improvement in PD following therapy for smokers may reflect the systemic effects of smoking on the host response and the healing process. The lesser reduction in microflora and greater post-therapy prevalence of organisms may reflect the deeper pockets seen in smokers and poorer clearance of the organisms. These detrimental consequences for smokers appear consistent in both aggressive and CP.

Mechanisms of action of environmental factors--tobacco smoking

AIM

To review the potential biological mechanisms underlying the effects of tobacco smoking on periodontitis.

MAIN FINDINGS

Smoking has major effects on the host response, but there are also a number of studies that show some microbiological differences between smokers and non-smokers. Smoking has a long-term chronic effect on many important aspects of the inflammatory and immune responses. Histological studies have shown alterations in the vasculature of the periodontal tissues in smokers. Smoking induces a significant systemic neutrophilia, but neutrophil transmigration across the periodontal microvasculature is impeded. The suppression of neutrophil cell spreading, chemokinesis, chemotaxis and phagocytosis have been described. Protease release from neutrophils may be an important mechanism in tissue destruction. Tobacco smoke has been found to affect both cell-mediated immunity and humoral immunity. Research on gingival crevicular fluid has demonstrated that there are lower levels of cytokines, enzymes and possibly polymorphonuclear cells in smokers. In vitro studies have shown detrimental effects of nicotine and some other tobacco compounds on fibroblast function, including fibroblast proliferation, adhesion to root surfaces and cytotoxicity.

CONCLUSION

Tobacco smoking has widespread systemic effects, many of which may provide mechanisms for the increased susceptibility to periodontitis and the poorer response to treatment.

Effect of triclosan on healing following non-surgical periodontal therapy in smokers

BACKGROUND

Tobacco smoking is an established risk factor for periodontitis, and is associated with periodontal attachment and tooth loss. Clinical studies have indicated that smoking may adversely affect and impede healing following periodontal therapy. Adjunctive antimicrobials, on the other hand, have been shown to enhance the effect of non-surgical periodontal therapy. The objective of this study was to evaluate the effect of a triclosan/copolymer/fluoride dentifrice on healing following non-surgical periodontal therapy in smokers.

METHODS

Sixty smokers (aged 35-59 years; 23 females) with chronic periodontal disease volunteered to participate in a double-blind, randomized, controlled, clinical trial. The subjects were randomly assigned to use a triclosan/copolymer/fluoride (30 subjects) or a standard fluoride (30 subjects) dentifrice and received detailed information on proper techniques for self-performed plaque control. The participants then received non-surgical periodontal therapy followed by periodontal maintenance care every 6 months over 24 months. Clinical recordings included evaluation of oral hygiene standards, gingival health, and periodontal status.

RESULTS

Subjects using the triclosan/copolymer/fluoride dentifrice exhibited significantly improved oral hygiene conditions, gingival health, and periodontal status compared with those using the standard fluoride dentifrice over the 24-month maintenance interval.

CONCLUSIONS

The results suggest that an oral hygiene regimen including a triclosan/copolymer/fluoride dentifrice may sustain the short-term effect of non-surgical periodontal therapy in smokers.

Effect of smoking and periodontal treatment on the subgingival microflora

BACKGROUND

The effect of smoking on the prevalence of periodontal pathogens after periodontal treatment is still not clear. Some studies found no effect of the smoking status on the prevalence of periodontal pathogens after therapy, whereas others did. The aim of this retrospective study was to investigate the influence of smoking on the treatment of periodontitis and the composition of the subgingival microflora.

METHOD

The study included 59 periodontitis patients (mean age 41.5 years): 30 smokers and 29 nonsmokers. The treatment consisted of initial periodontal therapy and, if necessary, surgery and/or antibiotics. Clinical and microbiological data were obtained before and after treatment at the deepest site in each quadrant. A pooled sample was analysed for the presence of Actinobacillus actinomycetemcomitans (Aa), Porphyromonas gingivalis (Pg), Prevotalla intermedia (Pi), Bacteroides forsythus (Bf), Fusobacterium nucleatum (Fn) and Peptostreptococcus micros (Pm).

RESULTS

For smokers and nonsmokers a significant improvement of the clinical condition was found after treatment. A decrease could be assessed for bleeding on probing (smokers: 0.46; nonsmokers: 0.52) and probing pocket depth (PPD) (smokers: 1.64 mm; nonsmokers: 2.09 mm). Furthermore, both groups showed gain of attachment (smokers: 0.68 mm; nonsmokers: 1.46 mm). No significant difference in bleeding on probing and PPD reduction was found between smokers and nonsmokers. In contrast, nonsmokers showed significantly more gain of attachment than smokers. The microbiological results revealed no differences in the prevalence of the various bacteria between smokers and nonsmokers before treatment. After treatment in nonsmokers, a significant decrease was found in the prevalence of Aa (11-3), Pg (17-7), Pi (27-11), Bf (27-11), Fn (28-20) and Pm (27-17). In smokers, a significant decrease could be shown only for the prevalence of Pg (15-5).

CONCLUSIONS

Nonsmokers showed more gain of attachment and a greater decrease in the prevalence of periodontal bacteria as compared to smokers. The phenomenon that among smokers, more patients remain culture positive for periodontal pathogens after therapy, may contribute to the often observed unfavourable treatment results in smoker periodontitis patients.

Prevalence and severity of periodontal disease at mandibular molar teeth in smokers with regular oral hygiene habits

BACKGROUND

Smoking appears to be detrimental to health because it has been associated with several diseases including cancer and cardiovascular diseases. Smoking also appears to be a major environmental factor associated with periodontal disease progression. The objective of this study was to evaluate the prevalence and severity of periodontal destruction as influenced by smoking in a Thai population.

METHODS

Gingival health and periodontal conditions at mandibular molar furcation sites in 120 Thai dental patients (60 smokers and 60 never-smokers, age range 31 to 60 years) with generally high oral hygiene standards and regular dental care habits were evaluated.

RESULTS

Smokers exhibited more frequent and severe mandibular molar periodontal destruction than never-smokers. The prevalence and severity of gingival recession, periodontal pocket formation, clinical attachment loss, furcation involvement, and tooth mobility were significantly increased in smokers compared to never-smokers. Seventy-three percent of the smokers exhibited furcation involvement in contrast to only 20% of the never-smokers.

CONCLUSIONS

The results of this study suggest that smoking appears to be a major environmental factor associated with accelerated periodontal destruction in adult smokers with generally high oral hygiene standards and regular dental care habits in a Thai population.

Smoking and periodontal disease

Numerous investigations of the relationship between smoking and periodontal disease have been performed over the last 15 years, and there now exists a substantial body of literature upon which this current review is based. From both cross-sectional and longitudinal studies, there appears to be strong epidemiological evidence that smoking confers a considerably increased risk of periodontal disease. This evidence is further supported by the data emanating from patients who stop smoking. These patients have levels of risk similar to those of non-smokers. Numerous studies of the potential mechanisms whereby smoking tobacco may predispose to periodontal disease have been conducted, and it appears that smoking may affect the vasculature, the humoral immune system, and the cellular immune and inflammatory systems, and have effects throughout the cytokine and adhesion molecule network. The aim of this review is to consider the evidence for the association between smoking and periodontal diseases and to highlight the biological mechanisms whereby smoking may affect the periodontium.

Pocket oxygen tension in smokers and non-smokers with periodontal disease

BACKGROUND

Smoking is associated with destructive periodontal disease. Pocket oxygen tension (pO2) is likely to be a major environmental determinant of the subgingival microflora, which is a primary etiological factor of the disease. This study aimed to compare the pocket pO2 in smokers and non-smokers with periodontal disease.

METHODS

Pocket oxygen tension was compared in 27 smokers and 34 non-smokers by considering 2 confounding factors, probing depth and oxygen saturation of hemoglobin (S(O2)), in the gingiva. The pO2 was determined using oxygen microelectrode by polarographic method with an electronic compensation circuit for subgingival temperature. Gingival S(O2) was determined using tissue reflectance spectrophotometry.

RESULTS

No significant difference was found in the modified gingival index and the plaque index between smokers and non-smokers. The pO2 was significantly lower in smokers (21.9+/-9.6 mmHg) than in non-smokers (33.4+/-8.4 mmHg). The difference was highly significant (P <0.0001) and was consistent when the confounding factors were considered. Correlation between the PO2 and probing depth approached statistical significance in smokers (r = -0.36, P = 0.0674) and significance in non-smokers (r = -0.41, P = 0.0174). Correlation of the PO2 to the gingival S(O2) was highly significant in non-smokers (r = 0.57, P = 0.0005), but no association was found in smokers (r = -0.08, P= 0.6975).

CONCLUSIONS

These findings indicate that pO2 is lower in smokers than in non-smokers, and that the pO2 in smokers is not influenced by gingival oxygen sufficiency. The present study may provide the basis of understanding environmental factors possibly associated with microbial flora in the pockets of smokers.

Effect of smoking on periodontal health in molar teeth

BACKGROUND

It is generally accepted that the primary cause of periodontitis is bacterial infection of long duration. In addition, there are several risk factors that may increase the probability and severity of periodontitis. For example, an increased breakdown of alveolar bone has been observed in smokers compared to never-smokers. The objective of this study was to investigate the association between cigarette smoking and periodontal health, in particular, furcation involvement in molar teeth.

METHODS

One hundred twenty (120) adult regular dental patients, presenting with at least 20 teeth each, third molars excluded, were evaluated. Sixty of the subjects consumed an average (+/- SD) of 16.8 +/- 3.8 cigarettes daily and had smoked for 21.4 +/- 5.7 years. The remaining subjects presented a negative history of smoking. Periodontal conditions for the molar teeth were recorded at the first and second mandibular molar buccal furcation area.

RESULTS

Oral hygiene standards and dental care habits did not differ notably between smokers and never-smokers. Smokers exhibited significantly fewer molar teeth than never-smokers (2.2 +/- 1.1 versus 3.0 +/- 0.8; P<0.01). Also, smokers exhibited significantly advanced gingival recession, probing depth, clinical attachment loss, furcation involvement, and tooth mobility compared to never-smokers (P<0.01).

CONCLUSIONS

The results of this study suggest that long-term cigarette smoking significantly worsens periodontal health including degree and incidence of furcation involvement in molar teeth.

Nicotine- and arecoline-induced interleukin-1 secretion and intercellular adhesion molecular-1 expression in human oral epidermoid carcinoma cells in vitro

The purpose was to examine interleukin (IL)-1 concentrations and intercellular adhesion molecule (ICAM)-1 expression in nicotine/arecoline-exposed oral KB CCL17 cultures. Enzyme-linked immunosorbent assay was used to quantify IL-1 concentrations in culture supernatants. A repeated-measures analysis of variance was used to identify differences among the groups. IL-1 beta concentrations increased by 2.6, 2.7 and 7.5 times those of the control in groups treated with 1 microM nicotine, arecoline or with both, respectively. IL-1 beta concentrations were more dramatically increased when the agents tested were at 100 microM concentration. Similar, although less dramatic, alterations in IL-1 alpha concentrations were observed. The fluorescence intensity of ICAM-1 (CD54) analysed by flow cytometry was also significantly increased in a dose-dependent manner when the cells were treated with nicotine and/or arecoline. Nicotine and arecoline therefore significantly increased IL-1 alpha and -1 beta secretions and the surface expression of ICAM-1 in KB CCL17 cells.

Phagocytic function of salivary PMN after smoking or secondary smoking

Alterations in polymorphonuclear leukocyte (PMN) functions, such as phagocytosis, chemotaxis, and oxidative burst, play a pivotal role in periodontal pathogenesis. In addition, previous studies have demonstrated a strong relationship between smoking and periodontal disease. In the present study, the effect of cigarette smoking or passive smoking (secondary smoking) on the phagocytic function of salivary PMN (SPMN) was investigated. Twenty volunteers with clinically healthy gingiva (10 smokers, 10 non-smokers) participated in this study. In a small room, the smokers and passive smokers (non-smokers) were instructed to smoke and breathe, respectively, in an identical, specific way for about 4 minutes. SPMN was isolated immediately before and after smoking or passive smoking. PMN was then incubated with fluoresbrite beads for 45 minutes at 37 degrees C and the phagocytic status estimated by using a flow cytometer. Cell viability was determined by trypan blue exclusion (smokers before smoking: 88.3%: smokers after smoking: 89.6%: non-smokers before passive smoking: 89.0%; non-smokers after passive smoking: 89.4%). In both smokers and passive smokers, the proportion of phagocytic cells increased between before and after smoking (smokers before: 33.2%; after: 42.1%: passive smokers before: 36.2%: after: 44.1%). Both increases were statistically significant (P < 0.01). These results demonstrate that the phagocytic activity of SPMN intensifies after smoking and passive smoking. They also suggest that certain substances in cigarette smoke, perhaps nicotine, overstimulate the host response in the oral cavity.

Periodontal diseases' contributions to cardiovascular disease: an overview of potential mechanisms

Periodontitis and atherosclerosis have complex etiologies, genetic and gender predispositions, and potentially share many risk factors-the most significant of which may be smoking status. These diseases also have many pathogenic mechanisms in common. It is becoming increasingly clear that infections and chronic inflammatory conditions such as periodontitis may influence the atherosclerotic process. The severity and chronicity of periodontal disease provides a rich source of subgingival microbial and host response products and effects over a long time period. The objective of this review is to consider the mechanisms whereby diseases such as periodontitis, which is chronic and Inflammatory In nature and initiated by microbial plaque, can predispose to atherosclerosis. In common with periodontal disease. the pathogenesis of atherosclerosis is not completely understood and both diseases are currently under Intensive investigation. Two main processes in particular are worthy of consideration and may provide the link between these 2 diseases, namely the lipopolysaccharide-related responses and the hyperresponsive monocyte phenomenon. Insufficient experimental evidence exists, however, to further support these hypotheses at present and clearly more research is needed on both of these processes and the interrelationships between both diseases.

The effect of smoking on individuals with minimal periodontal destruction

Recent studies have demonstrated that smoking is associated with periodontal destruction. The majority of these studies have focused on periodontal disease groups with moderate or severe periodontal destruction. Additionally, there have been few reports investigating the relationship between smoking and gingival recession. The goal of this report was to investigate the effect of smoking on periodontal destruction and recession in subjects with minimal or no interproximal attachment loss. This is a cross-sectional study of 142 non-smoking subjects and 51 smoking subjects. Subjects could have no more than one tooth with a site of interproximal attachment loss > or =2 mm. Subjects could, however, have attachment loss associated with recession. For three different methods of summarizing attachment loss measurements at a subject level, including average attachment loss, percentage of teeth with one site of 2 mm of attachment loss, and the percentage of teeth with one site of 5 mm of attachment loss, smoking subjects had approximately twice as much attachment loss than their non-smoking counterparts. Smoking subjects also had significantly greater recession (P < 0.05) [0.056+/-0.017 mm] than non-smoking subjects (0.025+/-0.005 mm). Recession sites occurred primarily on the facial surface of maxillary molars and bicuspids and mandibular central incisors and bicuspids. The results suggest a strong association between smoking and both attachment loss and recession in subjects who have minimal or no periodontal disease.

The effect of smoking on mechanical and antimicrobial periodontal therapy

The aim of this investigation was to evaluate the effect of smoking on the outcome of periodontal therapy. The study consisted of 54 patients who participated in a 4-group parallel-arm clinical trial on the efficacy of three locally delivered antimicrobial systems as adjuncts to scaling and root planing in the treatment of sites with persistent pocketing after a course of scaling and root planing. These groups included scaling and root planing either alone (S) (n = 3), or in conjunction with the application of 25% tetracycline fibers (S&T) (n = 13), 2% minocycline gel (S&Mi) (n = 14), or 25% metronidazole gel (S&Me) (n = 14). In each patient four pockets > 5 mm with bleeding on probing (BOP) and/or suppuration were studied. The number of subjects who smoked was: 8 (61.5%) in the S&T group, 8 (57.1%) in the S&Mi group, 6 (42.9%) in the S&Me group, and 6 (46.2%) in the S group. The probing depth, attachment level and other clinical parameters were assessed at baseline and 6 weeks after treatments. The clinical results of this comparative study have been previously reported. Regardless of the type of treatment, the change in the probing depth (delta PD) and attachment gain (delta AL) were greater in non-smoker subjects than smoker subjects. delta PD was 1.14 mm versus 0.76 mm (P = 0.019), and delta AL was 0.52 mm versus 0.50 mm at (P = 0.845) for non-smokers and smokers respectively. The analysis of variance using the general linear model (GLM) was used for delta PD and delta AL and took into account the variations in the treatments, number of smoker subjects per group, and baseline probing depth. There was a significant interaction between the "smoking" and the "baseline PD." Further analysis using linear regression indicated that, while there was a significant relationship between the baseline PD and the delta PD or delta AL among the non-smokers, weak and insignificant relationship existed among the smoker subjects. Thus, smoking may have an important role in determining the prognosis of periodontal treatment, particularly in persistent and deep pockets.

Risk assessment for periodontal diseases

Assessment of risk for periodontitis is still in its infancy. Nevertheless, a sufficient amount of dependable information exists to begin using risk assessment in the day to day practice of dentistry. The purpose of this paper is to summarise existing information about risks for periodontitis in a manner that is useful to practitioners. Risks for moderate to severe periodontitis that have been identified include cigarette smoking, advancing age, diabetes mellitus and certain other systemic conditions. These include, osteoporosis and HIV infection and conditions such as irradiation and immunosuppressive drugs that interfere with normal host defences, specific pathogenic bacteria in the subgingival flora, microbial deposits and poor oral hygiene status, bleeding on probing, previous disease experience and severity, and inheritance. Some risks such as pathogenic bacteria in the subgingival flora are strongly linked to causation of the disease while others such as bleeding on probing may indicate enhanced risk for future disease but are not known to be involved in causation and still others such as advancing age may be background factors that enhance susceptibility. While some risks such as cigarette smoking can be modified to lower the level of risk, others such as ageing are immutable and cannot be modified but need to be considered in overall risk assessment. A goal of periodontal diagnosis, treatment planning and therapy is to lower risk for future periodontal deterioration to the maximal extent. One approach to achieving this goal is described.

Elastase in gingival crevicular fluid from smokers and non-smokers with chronic inflammatory periodontal disease

OBJECTIVE

To compare elastase concentrations in gingival crevicular fluid (GCF) from individual sites of smokers and non-smokers.

MATERIALS AND METHODS

Twelve pairs of smokers and non-smokers with untreated, moderate to advanced chronic inflammatory periodontal disease were matched for gender, age, ethnicity and the clinical and radiographic extent of disease. Durapore filter strip samples were collected over 30 s from two mesiopalatal sites on upper left posterior teeth. Samples were analysed for: 1) polymorphonuclear neutrophil leucocyte (PMNL) cell counts; 2) PMNL elastase-alpha 1-antitrypsin complex in the GCF supernatant by ELISA; and 3) functional elastase, free or bound to alpha 2-macroglobulin, estimated from activity against N-tert-butoxycarbonyl-alanyl-prolyl-norvalyl-p-chlorothiobenzyl ester in supernatant and lysates of GCF PMNLs.

RESULTS

There were no differences in disease parameters between groups except that bleeding on probing was less extensive in smokers (P<0.001). Cell counts and elastase content of crevicular PMNLs showed no differences between groups. Lower concentrations of elastase were found in GCF supernatants from smokers than non-smokers. This difference was observed for functional elastase (mean [s.d.] = 30.21 [17.60] against 73.77 [75.26] ng microliter(-1), p<0.05) and elastase complexed with alpha 1-antitrypsin (8.97 [6.54] ng microliter(-1) against 25.71 [22.07] ng microliter(-1), p<0.001).

CONCLUSIONS

Smokers have lower elastase concentrations in GCF than non-smokers. Further investigation is required to elucidate the underlying cause and its relationship with periodontal disease.

The effect of smoking on the response to periodontal therapy

This study evaluated the effect of smoking on the clinical response to non-surgical and surgical periodontal therapy. 74 adult subjects with moderate to advanced periodontitis were treated according to a split-mouth design involving the following treatment modalities: coronal scaling, root planing, modified Widman surgery, and flap with osseous resectional surgery. Clinical parameters assessed included probing depth, probing attachment level, horizontal attachment level in furcation sites, recession, presence of supragingival plaque and bleeding on probing. Data were collected: initially, 4 weeks following phase-I therapy, 10 weeks following phase-II therapy and on a yearly basis during 6 years of maintenance care. Data analysis demonstrated that smokers exhibited significantly less reduction of probing depth and less gain of probing attachment level when compared to non-smokers immediately following active therapy and during each of the 6 years of maintenance (p < 0.05). A greater loss of horizontal attachment level was evident in smokers at each yearly exam during maintenance therapy (p < 0.05). There were no differences between groups in recession changes. In general, these findings were true for the outcomes following all 4 modalities of therapy and were most pronounced in the deepest probing depth category (> or = 7 mm). Statistical analysis showed a tendency for smokers to have slightly more supragingival plaque and bleeding on probing. In summary, smokers responded less favorably than non-smokers to periodontal therapy which included 3-month maintenance follow-up.

Association between cigarette smoking, bacterial pathogens, and periodontal status

The purposes of this study were to determine if: 1) an association exists between cigarette smoking and signs of periodontal disease after controlling for the confounding variables of age, sex, plaque, and calculus; 2) the prevalence of 5 bacteria commonly associated with periodontal disease differs between smokers and non-smokers; and 3) the presence of any of these bacteria or smoking are associated with a mean proximal posterior probing depth > or = 3.5 mm. Plaque, calculus, gingivitis, and probing depth were measured at the proximal surfaces of all teeth in one randomly selected posterior dental sextant in 615 adults. Subgingival plaque was sampled from the same sites and assayed for the presence of Porphyromonas gingivalis, Actinobacillus actinomycetemcomitans, Prevotella intermedia, Eikenella corrodens, and Fusobacterium nucleatum. A subsample of non-smokers (n = 126), who were similar to smokers (n = 63) with respect to age, sex, plaque, and calculus, was randomly drawn from the original sample. These two groups were then compared on the basis of clinical and microbial parameters. The results indicated that the odds of having a mean probing depth > or = 3.5 mm were 5 times greater for smokers than the non-smoker subsample (odds ratio = 5.3; 95% CI = 2.0 to 13.8). No statistically significant difference in the prevalence of any of the bacteria was found between smokers and the non-smoker subsample. Based on logistic regression analyses of each of the 5 bacteria and smoking, mean probing depth > or = 3.5 mm was significantly associated with the presence of A. actinomycetemcomitans, P. intermedia, E. corrodens, and smoking (P < 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)

The effect of nicotine on reproduction and attachment of human gingival fibroblasts in vitro

The ability of fibroblasts to reproduce and attach to teeth is of paramount importance in re-establishing the lost connective tissue attachment after periodontal therapy. This study examined the effect of nicotine, a major component of the particulate phase of tobacco smoke, on human gingival fibroblast (HGF) reproduction and attachment to tissue culture surfaces. Pooled HGF cultures made from explants of gingival biopsies were utilized between passages 5 and 10 and plated in 96-well plates at 1.0 x 10(4) cells per well. Cell numbers were determined using 3-(4,5-dimethylthiazol-2-y)-2,5-diphenyl tetrazolium bromide (MTT), which is a reflection of mitochondrial dehydrogenase activity. The concentrations of nicotine used were 0.025, 0.05, 0.1, 0.2, and 0.4 microM, the average serum concentration for a smoker being approximately 0.1 microM. The effect of continuous nicotine exposure on HGF reproduction was determined by incubating cell cultures and media containing nicotine for up to 48 hours. Residual toxicity was determined by preincubating cells with nicotine for 1 or 6 hours. HGF suspensions and increasing concentrations of nicotine were added together to determine the effect on attachment. Results showed an enhanced effect of nicotine on HGF attachment, with increasing numbers of cells attaching with increasing nicotine concentrations, compared to the control. Low concentrations of nicotine had a stimulatory effect on cell replication, while higher concentrations of nicotine appear to have no significant effect on HGF reproduction. The responses of cells to some concentrations of nicotine may persist after its removal.

Evidence for cigarette smoking as a major risk factor for periodontitis

The role of smoking as a risk factor for periodontitis was assessed separately in diabetic and nondiabetic study groups. Subject listings stratified for age (19 to 40 years) and sex were obtained for subjects with insulin-dependent diabetes mellitus (IDDM) and nondiabetic subjects. For both the IDDM group (n = 132) and the nondiabetic group (n = 95), age and sex stratified samples were constructed by random selection of subjects from each subject listing. Patients were recruited by phone, examined, and their medical and dental histories obtained. Among nondiabetic subjects, the prevalence of periodontitis was markedly higher among current smokers compared with never smokers (P < or = 0.005) in both the 19 to 30 year-old (46% vs. 12%) and 31 to 40 year-old groups (88% vs. 33%). The subject mean percent of sites with gingival pocket depth > or = 4 mm was higher among current smokers than never smokers (P = 0.001) in the 19 to 30 (8.2% vs. 3.4%) and 31 to 40 (14.3% vs. 4.3%) age groups. The effects of smoking among IDDM subjects were similar to that observed in the nondiabetic population. There were no differences between current and never smokers in the proportion of sites positive for plaque. Attributable risk percents from prevalence data suggest that among nondiabetic subjects, a large proportion, perhaps as much as 51% of the periodontitis in the 19 to 30 year old group and 32% of the periodontitis in the 31 to 40 year old group, is associated with smoking.(ABSTRACT TRUNCATED AT 250 WORDS)

Refractory periodontitis associated with abnormal polymorphonuclear leukocyte phagocytosis and cigarette smoking

To learn if refractory periodontitis may be associated with defects in peripheral blood polymorphonuclear leukocyte (PMN) function, phagocytosis and chemotaxis were analyzed in 31 otherwise healthy patients and 12 unaffected controls. When compared to controls, no chemotactic defects to 10 nM f-Met-Leu-Phe (fMLP) were detected. In contrast, phagocytosis was significantly impaired (P < 0.001). The mean rates of adhesion and ingestion of opsonized Staphylococcus aureus by PMNs were 7.1 +/- 1.7 (+/- SD) and 1.4 +/- 0.5 bacteria/100 PMNs/minute respectively for patients, and 11.0 +/- 2.4 and 3.1 +/- 0.6 for unaffected, healthy controls. While the quality of oral hygiene and access to dental care were high, a retrospective search for associated environmental variables showed that 90% (28 of 31) of the refractory patients were smokers. The frequency of smokers is particularly striking, since only 21% of adults in Minnesota use tobacco regularly. These data suggest that there is a strong association between a peripheral blood PMN defect and refractory periodontitis. Furthermore, these studies suggest that tobacco use may contribute to this association.

Cigarette smoking in a periodontal practice

This case-control study compares the prevalence of cigarette smoking among patients in a periodontal practice (cases) with that of patients in referring general dental practices (controls). Smoking histories of patients (age greater than or equal to 25 years) in a periodontal practice and five general dental practices were obtained by questionnaire. From the general practices, only patients reporting negative histories for periodontitis were studied. Periodontal status of the periodontal practice patients was based on bone loss from full mouth radiographic surveys and gingival pocket depths. Patients were stratified by age (25 to 40, 41 to 55, and greater than 55 years) and sex. The combined frequency of current or former cigarette smoking reported by 196 periodontal practice patients with moderate or advanced periodontitis (M-A perio group) was higher than that reported by 209 general dental practice patients (gen prac group) in all age and sex categories. The age and sex adjusted summary odds ratio for a positive smoking history among M-A perio subjects relative to gen prac subjects was 2.6 (P less than 0.001). Separate corresponding odds ratios (age and sex adjusted) for current smoking versus never smoking in the two groups were 3.3 (P less than 0.001) and for former smoking versus never smoking 2.1 (P less than 0.004). Among current smokers, patients in the M-A perio group reported heavy smoking (greater than 10 cigarettes/day) relatively more often than control subjects (adjusted R.O. = 5.7; P less than 0.001). In the M-A perio group the frequency of current smoking increased with disease severity.(ABSTRACT TRUNCATED AT 250 WORDS)

Smoking and periodontal disease. A review of the literature

The literature related to smoking and periodontal disease is reviewed. The effects of smoking on oral hygiene, gingivitis, necrotizing gingivitis, periodontitis, bacteria and the host's response are presented. From this review it is apparent that while the relationship between smoking and periodontal disease needs further study, smoking is detrimental to periodontal health as it worsens the oral hygiene status and depresses the host's defense posture.