Influence of risk factors on the pathogenesis of periodontitis

Dose-effect relation of smoking and the interleukin-1 gene polymorphism in periodontal disease

BACKGROUND

Periodontitis is a bacterial inflammatory disease leading to attachment loss with the consequence of tooth loss. There exists a multifactorial risk pattern including bacterial challenge, smoking, age, gender, diabetes, and socioeconomic and genetic factors. Smoking has the highest impact on the course of the disease modulated by all the other factors. Here, we report the relationship between smoking and the genetic polymorphism of interleukin-1 (IL-1).

METHODS

In a randomly selected population-based study, we genotyped 1,085 test persons for the IL-1 genotype, examined their periodontal status, and assessed their smoking behavior including present and past quality and quantity of smoking.

RESULTS

There was a significant dose-effect relationship between the exposure to tobacco smoke and the extent of periodontal disease assessed as attachment loss and tooth loss. Moreover, there was a gene-environmental interaction. Subjects bearing at least one copy of the variant allele 2 at positions IL-1A -889 and IL-1B +3954 (genotype positive) had an enhanced smoking-associated periodontitis risk as compared to their IL-1 genotype-negative counterparts. With genotype-negative non-smokers as a reference, logistic regression resulted in odds ratios of 0.98 (95% confidence interval: 0.83 to 1.14), 2.37 (1.96 to 2.87), and 4.50 (2.30 to 8.82) for genotype-positive non-smokers, genotype-negative smokers, and genotype-positive smokers, respectively.

CONCLUSIONS

There is a gene-environmental interaction between smoking and the IL-1 genetic polymorphism. Smokers bearing the genotype-positive IL-1 allele combination have an increased risk of periodontitis. The IL-1 genotype has no influence in non-smokers.

Effect of Restraint Stress on the Progression of Experimental Periodontitis in Rats

BACKGROUND

A hypothesis of an increased risk for destructive periodontal diseases due to psychological stress has long been promoted. However, the research on stress and periodontal disease is still in its infancy. One of the reasons is thought to be that there is no suitable animal model for investigating the relationship.

METHODS

One hundred male Wistar rats were included. A nylon ligature was placed around the second right maxillary molars. The animals were then divided into group S, exposed to a restraint stress for 12 hours/day for up to 10 days, and group N, controls. Ten animals were sacrificed on days 2, 4, 6, 8, and 10. Blood samples were taken, and the blood glucose level and the concentrations of adrenocorticotropic hormone, corticosterone, and adrenaline were measured as the markers of stress. The atrophies of the thymus and the spleen were measured. The furcation area of the second maxillary molars was examined histologically and histometrically.

RESULTS

In group S, all values of stress markers were increased, and the thymus and the spleen were atrophied. Whereas group N showed only slight alveolar bone resorption, a marked alveolar bone resorption occurred in group S between days 8 and 10. An increase in beaded nerve terminals occurred around the vessels in the furcation area of group S.

CONCLUSION

The results of the present study suggest that the restraint stress modulates the progression of periodontal inflammation and that this rat model is suitable for investigating the association between stress and periodontal disease.

Longitudinal validation of a risk calculator for periodontal disease

BACKGROUND

Risk assessment and utilization of the results are important components of prevention, diagnosis and treatment of periodontal diseases. Risk assessment is relatively new to dentistry. Currently risk is assessed by subjective evaluation and results vary widely among clinicians. We have developed a computer-based risk assessment tool, the Periodontal Risk Calculator (PRC), for objective, quantitative assessment of risk. The purpose of the study reported here was to evaluate the accuracy and validity of this tool.

METHODS

Clinical records and radiographs of 523 subjects enrolled in the VA Dental Longitudinal Study of Oral Health and Disease, covering a period of 15 years, were used. Information from baseline examinations was entered into the risk calculator and a risk score on a scale of l-5 for periodontal deterioration was calculated for each subject. Actual periodontal status in terms of alveolar bone loss determined using digitized radiographs, and tooth loss determined from the clinical records, was assessed at years 3, 9 and 15. The strength of the association between risk prediction and actual outcome was determined statistically.

RESULTS

The risk scores were strong predictors of future periodontal status measured as worsening severity and extent of alveolar bone loss and tooth loss, especially loss of periodontally affected teeth. Over the entire 15-year period, risk scores consistently ranked groups from least to most bone loss and tooth loss. Risk groups differed greatly from one another. By year 3, the incidence rate of bone loss of group 5 was 3.7-fold greater than for group 2, and by year 15, the loss of periodontally affected teeth was 22.7-fold greater than for group 2 (p<0.001). By year 15, 83.7% of subjects in risk group 5 had lost one or more periodontally affected teeth compared to 20.2% of subjects in group 2.

CONCLUSIONS

Risk scores calculated using the PRC and information gathered during a standard periodontal examination predict future periodontal status with a high level of accuracy and validity. Use of the risk assessment tool over time may be expected to result in more uniform and accurate periodontal clinical decision-making, improved oral health, reduction in the need for complex therapy and reduction in health-care cost.

Antibacterial activity of medicinal plant extracts against periodontopathic bacteria

This study was performed to evaluate the antibacterial activity of Althaea officinalis L. roots, Arnica montana L. flowers, Calendula officinalis L. flowers, Hamamelis virginiana L. leaves, Illicium verum Hook. fruits and Melissa officinalis L. leaves, against anaerobic and facultative aerobic periodontal bacteria: Porphyromonas gingivalis, Prevotella spp., Fusobacterium nucleatum, Capnocytophaga gingivalis, Veilonella parvula, Eikenella corrodens, Peptostreptococcus micros and Actinomyces odontolyticus. The methanol extracts of H. virginiana and A. montana and, to a lesser extent, A. officinalis were shown to possess an inhibiting activity (MIC < or = 2048 mg/L) against many of the species tested. In comparison, M. officinalis and C. officinalis extracts had a lower inhibiting activity (MIC > or = 2048 mg/L) against all the tested species with the exception of Prevotella sp. Illicium verum methanol extract was not very active though it had a particular good activity against E. corrodens. The results suggest the use of the alcohol extracts of H. virginiana, A. montana and A. officinalis for topical medications in periodontal prophylactics.

Herpesviral-bacterial interactions in aggressive periodontitis

BACKGROUND

Human cytomegalovirus, Epstein-Barr virus and herpesvirus co-infections occur with significantly higher frequency in actively progressing than in stable periodontitis sites of adolescents and young adults. Also, periodontal presence of cytomegalovirus and Epstein-Barr virus is associated with increased occurrence of subgingival Porphyromonas gingivalis, Bacteroides forsythus, Dialister pneumosintes, Prevotella intermedia, Prevotella nigrescens, Treponema denticola and Actinobacillus actinomycetemcomitans.

AIM

This article reviews the evidence linking herpesviruses to the development of aggressive periodontitis and suggests a potential mechanism for herpesviral acceleration of the periodontal disease process.

CONCLUSIONS

It seems to be a reasonable supposition that the etiopathogenesis of various types of aggressive periodontitis includes the combined action of herpesviruses and specific bacterial species. New vaccines and vaccination technologies that are being developed against herpesviruses warrant testing for their ability to induce a protective immune response against destructive periodontal disease. Clearly, the importance of combined herpesviral-bacterial infections and associated host responses in the development of periodontitis needs to be studied further.

Assessing periodontal disease risk: a comparison of clinicians' assessment versus a computerized tool

BACKGROUND

The authors conducted a study to compare risk scores assigned by subjective expert clinician opinion with quantitative scores generated for the same subjects using the Periodontal Risk Calculator, or PRC.

METHODS

The authors assembled a group of 107 subjects and performed standard periodontal examinations. The authors entered the resulting information into the PRC and calculated risk scores for two and four years, assuming no treatment would be performed. Using the same subject records, three groups of expert clinicians assigned risk scores for years 2 and 4. The authors analyzed the data to reveal the extent of interevaluator variation and the level of agreement between expert clinician scores and PRC scores.

RESULTS

The extent of variation among scores assigned by individual expert clinicians was greater than the authors had expected. Expert clinicians consistently assigned more subjects to PRC risk group 2 and fewer to risk group 5 than did the PRC. The authors observed very high heterogeneity in the risk scores expert clinicians assigned to patients in each of the PRC-assigned groups. Thus, expert clinicians varied greatly in evaluating risk and, relative to the PRC, they appeared to underestimate periodontitis risk, especially for high-risk patients.

CONCLUSIONS AND PRACTICE IMPLICATIONS

The authors' observations suggest that use of risk scores generated for individual patients by subjective expert clinician opinion about risk in periodontal clinical decision making could result in the misapplication of treatment for some patients and support the use of an objective tool such as the PRC. Use of the PRC over time may be expected to result in more uniform and accurate periodontal clinical decision making, improved oral health, reduction in the need for complex therapy and reduction in health care costs.

Assessment of periodontal conditions and systemic disease in older subjects

BACKGROUND

An increased risk for periodontitis has been associated both with type-1 or insulin dependent diabetes (IDDM) and with type-2 or non-insulin dependent diabetes (NIDDM).

AIMS

1) To describe and analyze periodontal conditions in older low-income ethnic diverse subjects with or without a diagnosis of diabetes. 2) To assess to what extent diabetes mellitus is associated with periodontal status, and 3) how periodontitis ranks as a coexisting disease among other diseases in subjects with diabetes mellitus.

MATERIAL AND METHODS

Radiographic signs of alveolar bone loss were studied in 1101 older subjects 60-75 years old (mean age 67.6, SD+/-4.7). The number of periodontal sites and the proportions of teeth with probing depth (PD) > or =5 mm, clinical attachment levels (CAL) > or =4 mm were studied in a subset of 701 of the subjects.

RESULTS

IDDM was reported by 2.9% and NIDDM by 9.2% of the subjects. The number of remaining teeth did not differ by diabetic status. The number of sites with PD > or =5 mm and the proportion of PD with > or =5 mm was significantly smaller in the non-diabetic group (chi2=46.8, p<0.01, and chi2=171.1, p<0.001, respectively). Statistical analysis failed to demonstrate group differences for the number and proportions of sites with CAL > or =4 mm and for radiographic findings of alveolar bone loss. Combining all periodontal parameters revealed that the Mantel-Haenszel common odds of having IDDM/NIDDM and periodontitis was 1.8 : 1 (95% CI: 1.1-3.1, p<0.03). The common odds ratio estimate of an association between heart disease and diabetes was 3.6 : 1 (95% CI: 2.1-2.6, p<0.001).

CONCLUSIONS

Probing depth differences between IDDM/NIDDM vs. non-diabetic subjects may reflect the presences of pseudo-pockets and not progressive periodontitis in many subjects with diabetes mellitus. Periodontitis is not a predominant coexisting disease in older subjects with diabetes mellitus.

Expression of vascular endothelial growth factor in human periodontal tissues: comparison of healthy and diabetic patients

BACKGROUND

Vascular endothelial growth factor (VEGF) induces proliferation of endothelial cells, stimulates angiogenesis, and increases vascular permeability, but information about its role in periodontal lesions is limited. The aim of this study is to determine the association between VEGF expression in healthy and periodontally diseased tissues of healthy and diabetic patients.

METHODS

Ten systemically healthy and 10 Type 2 diabetic patients (DM) all diagnosed with periodontitis were enrolled into the study. Gingival samples were collected from both periodontal and healthy sites in all patients. Each patient served as his/her own control. Additionally, 10 people without any systemic or periodontal diseases were enrolled as a negative control group.

RESULTS

In the negative control group tissue samples, no VEGF expression was observed. Among the 10 systemically healthy people, no evidence of VEGF was observed in healthy gingival samples, but was found in diseased tissues in 2 cases. In the diabetic patients, VEGF was observed in 4 healthy gingival tissues and in 6 periodontal sites. VEGF was intensely present in monocytes and macrophages.

CONCLUSION

The results of this study show that VEGF is increased in gingival tissues of diabetic patients, especially those with periodontal disease.

Cytomegalovirus periodontal presence is associated with subgingival Dialister pneumosintes and alveolar bone loss

Destructive periodontal disease is associated with human cytomegalovirus (HCMV), Epstein-Barr type 1 virus (EBV-1) and other members of the Herpesviridae family as well as with various gram-negative anaerobic bacteria, including the Dialister pneumosintes species. This study aimed to determine possible interrelationships between periodontal HCMV, EBV-1, herpes simplex virus and D. pneumosintes, and relate the microbiological findings to periodontitis clinical status. Sixteen subjects each contributed paper point samples from two progressing and two stable periodontitis lesions, as determined by ongoing loss of probing attachment. Polymerase chain reaction methodology was used to identify the study herpesviruses and D. pneumosintes. Chi-squared tests, Fisher exact tests and multivariate logistic regression were employed to identify statistical associations among herpesviruses, bacteria and clinical variables. HCMV, and no other virus or combination of viruses, was positively associated with the presence of D. pneumosintes, and the relationship was specific for individual periodontitis sites with no detectable subject effect. D. pneumosintes was in turn positively associated with periodontal pocket depth and disease-active periodontitis. When the average percentage of alveolar bone loss in all teeth was treated as a response, HCMV remained significant even after D. pneumosintes was included in the model, suggesting that both HCMV and D. pneumosintes affected bone loss or, alternatively, HCMV affected factors not studied that themselves can induce bone loss. We hypothesize that periodontal HCMV sets the stage for subgingival proliferation of D. pneumosintes and subsequent periodontal disease progression. Studies on herpesviral-bacterial interactions may hold great promise for delineating important etio-pathogenic aspects of destructive periodontal disease.

Inflammatory mediators and periodontitis in patients with asymptomatic third molars

PURPOSE

Our goal was to report the detection and levels of gingival crevicular fluid (GCF) inflammatory mediators, sampled at the mesial of 4 first molars and distal of 4 second molars, in 316 patients with asymptomatic third molars.

PATIENTS AND METHODS

Levels of GCF inflammatory mediators, interleukin (IL)-1 beta and prostaglandin (PG)E(2), were determined and log transformed for each patient. Z scores were calculated using the mean and standard deviation of the log values for the entire sample of 316 patients. The log mediator levels and Z scores of patients who had probing depths (PDs) less than 5 mm (n = 238) were compared with patients with at least 1 PD equal to or greater than 5 mm (n = 78) on the distal of second molars or around third molars. A periodontal Composite GCF Inflammation Score was calculated for each patient by summing the Z scores obtained for IL-1 beta and PGE(2) for that patient.

RESULTS

The levels of GCF IL-1 beta and PGE(2) were higher if a patient had a PD equal to or greater than 5 mm in the third molar region. The Composite GCF Inflammation Score indicated "elevated inflammation" if a PD equal to or greater than 5 mm was found in the third molar region as well.

CONCLUSIONS

These data suggest that asymptomatic patients with PD equal to or greater than 5 mm in the third molar region with associated periodontal attachment loss have increased levels of biochemical mediators of inflammation compared with patients with PD less than 5 mm. These findings are consistent with the concept that early periodontitis in young adults that initiates in the third molar region is associated with increases in key inflammatory mediators.

Periodontal pathology associated with asymptomatic third molars

PURPOSE

We report the prevalence of periodontal probing depth (PD) as a clinical measure of the extent of periodontitis associated with asymptomatic third molars at the initial examination in a cohort of patients enrolled in an institutional review board-approved longitudinal clinical trial.

PATIENTS AND METHODS

Three hundred twenty-nine healthy patients were enrolled during a 30-month period. Full mouth periodontal probing that included third molars was conducted to determine periodontal status. Panoramic radiographs were taken to assess the degree of eruption of the third molars and the angulation of third molars compared with the adjacent second molar. Vertical bitewing radiographs were analyzed to detect alveolar bone levels relative to the cementoenamel junction on the distal of second molars.

RESULTS

Twenty-five percent (82 of 329) of all enrolled patients, and 34% (14 of 41) of black patients, had at least one PD equal to or greater than 5 mm on the distal of a second molar or around a third molar. PD equal to or greater than 5 mm was associated with periodontal attachment loss of at least 1 mm in every patient; PD equal to or greater than 5 mm was associated with attachment loss equal to or greater than 2 mm in 80 of 82 patients. A higher proportion of patients 25 years old or older had a PD equal to or greater than 5 mm on the distal of second molars or around third molars compared with patients younger than 25 years (33% vs 17%, P =.002). The distals of second molars and third molars in the mandible were affected more often than in the maxilla (25% vs 5%, P =.0001).

CONCLUSIONS

Our data indicating that 25% of patients with retained asymptomatic third molars have considerable periodontal pathology in the third molar region were unexpected. National epidemiologic surveys indicate a much lower rate of periodontitis in the population younger than 35 years.

A cross-sectional study of dentine hypersensitivity

AIM

The aim of this study was to establish the prevalence of dentine hypersensitivity in a cross-sectional study of patients visiting general dental practitioners in the United Kingdom over a period of one calendar month.

METHODS

Nineteen dental practioners examined 4841 patients over a period of one calendar month and patients that had dentine hypersensitivity diagnosed were questioned further about their occupation and smoking habits. The amount of buccal gingival recession associated with the sensitive teeth was also recorded using a study form.

RESULTS

201 patients were diagnosed as having dentine hypersensitivity, giving a prevalence figure of 4.1%. The commonest teeth affected were the upper premolar teeth and the commonest initiating factor was cold drinks. A tendency for a greater number of sensitive teeth was also found for patients with periodontal disease who also smoked. There was also a tendency for the patients with sensitive teeth to come from higher social groups.

Oral cancer: prevention and detection in primary dental healthcare

The incidence of oral cancer is rising in the UK. Mortality from the disease remains high and survival has not improved significantly in the last 30 years. The primary dental health team has an integral role in the delivery of oral health promotion and prevention advice and in the early detection of oral malignancy and potentially malignant lesions. Both prevention and early detection within the general dental practice setting have a potential impact on overall incidence, morbidity and mortality from oral cancer. This paper details the primary dental healthcare team's roles in delivering smoking cessation and alcohol reduction counselling, in the early detection by oral examination, and in the process of prompt referral.

Full-mouth therapy versus individual quadrant root planning: a critical commentary

BACKGROUND

This commentary compares the abilities of full-mouth disinfection (FDIS), full-mouth root planing (FRP), and partial-mouth disinfection (PDIS) to improve periodontal health. FDIS consists of 4 quadrants of root planing completed within 24 hours with adjunctive chlorhexidine therapies (e.g., rinsing, subgingival irrigation, tongue brushing). FRP denotes 4 quadrants of root planing performed within 24 hours, and PDIS refers to root planing individual quadrants of the dentition, spaced 2 weeks apart. A basic premise of administering full-mouth therapy (FDIS or FRP) is to eliminate or reduce bacterial reservoirs within the oral cavity that could inhibit optimal healing of treated sites or cause periodontal disease initiation or progression.

METHODS

Controlled clinical trials that compared the abilities of PDIS and full-mouth root planing with and without adjunctive chlorhexidine chemotherapy to alter periodontal status were reviewed.

RESULTS

Several studies conducted at one treatment center indicated that FDIS and FRP attained greater therapeutic improvements than PDIS with respect to decreasing probing depths (PD), gaining clinical attachment (CAL), diminishing bleeding upon probing, and reducing the subgingival microflora. However, the magnitude of PD reductions and gains of clinical attachment must be carefully interpreted, because initial PD measurements were usually determined after scaling and root planing, which may have caused the results to be overstated. Furthermore, in studies that addressed the utility of FDIS, it was not possible to determine if benefits induced beyond PDIS were due to FRP or administration of multifaceted intraoral chlorhexidine treatments ora combination of both therapies. One investigation that had protocol limitations indicated that similar results were attained by FRP with and without adjunctive chemotherapy. In contrast, recent studies from 2 other treatment centers indicated that there were no significant differences when the efficacy of quadrant-by-quadrant root planing was compared to FRP or FDIS with regard to PD reduction, gains of clinical attachment, and impact on the magnitude and quality of the immune response. POSSIBLE CLINICAL IMPLICATIONS: Conceptually, full-mouth therapy (FRP or FDIS) could reduce the number of patient visits and facilitate more efficient use of treatment time. In addition, there appears to be no major adverse reactions to full-mouth root planing with or without adjunctive chemotherapy. However, small study populations and non-corroborating data from different treatment centers indicate that additional randomized clinical trials are needed to determine if full-mouth therapy provides clinically relevant improvements beyond PDIS.

Glycemic control of type 2 diabetes and severe periodontal disease in the US adult population

OBJECTIVE

We investigated the association between glycemic control of type 2 diabetes mellitus (type 2 DM) and severe periodontal disease in the US adult population ages 45 years and older.

METHODS

Data on 4343 persons ages 45-90 years from the National Health and Nutrition Examination Study III were analyzed using weighted multivariable logistic regression. Severe periodontal disease was defined as 2 + sites with 6 + mm loss of attachment and at least one site with probing pocket depth of 5 + mm. Individuals with fasting plasma glucose > 126 mg/dL were classified as having diabetes; those with poorly controlled diabetes (PCDM) had glycosylated hemoglobin > 9% and those with better-controlled diabetes (BCDM) had glycosylated hemoglobin <or= 9%. Additional variables evaluated in multivariable modeling included age, ethnicity, education, gender, smoking status, and other factors derived from the interview, medical and dental examination, and laboratory assays.

RESULTS

Individuals with PCDM had a significantly higher prevalence of severe periodontitis than those without diabetes (odds ratio = 2.90; 95% CI: 1.40, 6.03), after controlling for age, education, smoking status, and calculus. For the BCDM subjects, there was a tendency for a higher prevalence of severe periodontitis (odds ratio = 1.56; 95% CI: 0.90, 2.68).

CONCLUSION

These results provide population-based evidence to support an association between poorly controlled type 2 diabetes mellitus and severe periodontitis.

Validity and accuracy of a risk calculator in predicting periodontal disease

BACKGROUND

Research on the pathobiology of periodontal diseases has increased our knowledge of these diseases and is fostering a transition from the repair model to the medical or wellness model of periodontal care. Successful application of the wellness model depends on an accurate and valid assessment of disease risk, as well as institution of risk reduction as an integral part of prevention and treatment. A computer-based risk assessment tool has been developed.

METHODS

The authors reviewed clinical records and radiographs of 523 subjects enrolled in the Veterans Affairs Dental Longitudinal Study to evaluate the validity of risk prediction using the computer-based tool. Data from baseline examinations was entered into the risk calculator, and a risk score on a scale from 1 (lowest risk) to 5 (highest risk) was calculated for each subject to predict periodontal deterioration. Actual periodontal status in terms of alveolar bone loss (determined from digitized radiographs) and tooth loss (determined from clinical records) was assessed at years 3, 9 and 15. The authors determined the statistical strength of the association between risk prediction and actual outcome.

RESULTS

The risk scores were strong predictors of periodontal status, as measured by alveolar bone loss and loss of periodontally affected teeth. Risk scores consistently ranked risk score groups from least to most bone loss and tooth loss. Compared with a risk score of 2, the relative risk of tooth loss was 3.2 for a risk score of 3, 4.5 for a risk score of 4 and 10.6 for a risk score of 5.

CONCLUSIONS AND PRACTICE IMPLICATIONS

Use of the risk assessment tool over time may result in more uniform and accurate periodontal clinical decision-making, improved oral health, reduction in the need for complex therapy, reduction in health care costs and a hastening of the transition from a repair model to a wellness model of care.

Clinical utility of a genetic susceptibility test for severe chronic periodontitis: a critical evaluation

BACKGROUND

A genetic susceptibility test for severe chronic periodontitis is now commercially available. It detects the simultaneous presence of a specific form of two interleukin genes--allele 2 at the IL1A+4845 and IL1B+3954 loci. Patients are referred to as being "genotype-positive" if both of these alleles are present. A fundamental premise of the test is that a combination of these alleles is responsible for increased secretion of IL-beta, which results in a hyperinflammatory response to a bacterial challenge, thereby predisposing a person to develop severe chronic periodontitis.

TYPES OF STUDIES REVIEWED

The authors reviewed controlled clinical trials that assessed the association between specific genotypes and the patient's susceptibility to increased bleeding on probing, periodontitis and loss of teeth or dental implants.

RESULTS

The relationship between specific IL-1 genotypes and the level of IL-1beta in the gingival crevicular fluid is unclear. Similarly, the ability of the genetic susceptibility test to forecast which patients will develop increased bleeding on probing, periodontitis, or loss of teeth or dental implants is ambiguous.

CLINICAL IMPLICATIONS

Additional prospective clinical trials are needed to determine the risk of developing periodontitis or peri-implantitis when allele 2 at the IL1A+4845 and IL1B+3954 loci is present. Therefore, it is unclear how results of the genetic susceptibility test can be used to alter patients' periodontal maintenance schedules or to change treatment regimens in periodontally symptomatic or asymptomatic patients.

Oral health and cardiovascular disease in Sweden

OBJECTIVE

The purpose of the present study was to assess the relation between dental health and cardiovascular disease in an adult Swedish population.

MATERIAL AND METHOD

A questionnaire was sent to 4811 randomly selected Swedes. It contained 52 questions about dental care habits, oral health, cardiovascular disease and their socio-economic situation. Odd ratios for all cardiovascular diseases (CVD) and the subgroup myocardial infarction, stroke and high blood pressure were calculated with a logistic regression model adjusted for age, gender, smoking, income, civil status and education. These ratios were calculated for subjects > or =41 years since few people suffer from CVD before this.

RESULTS

The national questionnaire was answered by 2839 (59%) people between 20-84 years of age and, of them, 1577 were 41 years of age or more. We found a significant association between self-reported bleeding gums (odds ratio 1.60, p=0.0017), presence of dentures (odds ratio 1.57, p=0.0076) and known CVD, which has also been reported in international studies. However, no association between loose teeth, deep pockets and known CVD was detected.

CONCLUSION

The results indicate that oral health and, especially gingival inflammation is associated with CVD.

A critical assessment of interleukin-1 (IL-1) genotyping when used in a genetic susceptibility test for severe chronic periodontitis

BACKGROUND

This review addresses the ability of a commercially available genetic susceptibility test to determine the risk of developing severe chronic periodontitis. The test is used to detect the simultaneous occurrence of allele 2 at the IL-1A+4845 and IL-1B+3954 loci. If both of these polymorphisms are present, patients are referred to as being genotype-positive and considered predisposed to becoming afflicted with severe chronic periodontitis. A basic premise of this test is the assumption that individuals who are genotype-positive produce increased amounts of IL-beta in response to microbial lipopolysaccharides, which allegedly predisposes them to an exaggerated inflammatory response and an increased incidence of chronic periodontitis.

METHODS

Controlled clinical trials were selected that evaluated the ability of the genetic test to predict which patients were susceptible to bleeding upon probing, periodontitis, peri-implantitis, and tooth loss.

RESULTS

Comparison of results from test (genotype-positive) and control groups (genotype-negative) revealed that there is ambiguity with regard to predicting which patients will manifest elevated sub-gingival levels of IL-beta. Similarly, it is questionable if the test is able to forecast which individuals will demonstrate an increased occurrence of bleeding upon probing, diminished clinical attachment, decreased osseous support, or loss of teeth.

CONCLUSIONS

There are many unanswered questions concerning the utility of detecting allele 2 at the IL-1A+4845 and IL-IB+3954 loci to foretell which patients will develop severe chronic periodontitis. Therefore, clinicians must cautiously interpret results obtained with the commercially available genetic susceptibility test before they alter maintenance schedules or treatment regimens of symptomatic or asymptomatic patients.

Bidirectional interrelationships between diabetes and periodontal diseases: an epidemiologic perspective

This review evaluates evidence for a bidirectional relationship between diabetes and periodontal diseases. A comprehensive Medline search of the post-1960 English language literature was employed to identify primary research reports of relationships between diabetes and periodontal diseases. Reports included in the review on the adverse effects of diabetes on periodontal health (DM-->PD) were restricted to those comparing periodontal health in subjects with and without diabetes. Review of adverse affects of periodontal infection on glycemic control included reports of periodontal treatment studies and follow-up observational studies in which changes in glycemic control could be assessed. Observational studies reporting DM-->PD provided consistent evidence of greater prevalence, severity, extent, or progression of at least one manifestation of periodontal diseases in the large majority of reports (supportive evidence in 44/48 total reviewed; 37/41 cross-sectional and 7/7 cohort). Additionally, there were no studies reviewed with superior design features to refute this association. Treatment studies provided direct evidence to support periodontal infection having an adverse, yet modifiable, effect on glycemic control. However, not all investigations reported an improvement in glycemic control after periodontal treatment. Additional evidence to support the effect of severe periodontitis on increased risk for poorer glycemic control comes from 2 follow-up observational studies. The evidence reviewed supports viewing the relationship between diabetes and periodontal diseases as bidirectional. Further rigorous, systematic study is warranted to establish that treating periodontal infections can be influential in contributing to glycemic control management and possibly to the reduction of the burden of complications of diabetes mellitus.

Association between betel quid chewing, periodontal status and periodontal pathogens

The present investigation examined whether an association exists between betel quid chewing and signs of periodontal disease and determined the prevalence of Actinobacillus actinomycetemcomitans and Porphyromonas gingivalis by polymerase chain reaction. The periodontal status of 34 betel quid chewers and 32 non-betel quid chewers were compared. A significantly higher prevalence of bleeding on probing was found in betel quid chewers than non-chewers among the subjects with higher plaque level, greater gingival inflammation, deeper probing depth or greater attachment loss. Also, the results suggested that betel quid chewers may harbor higher levels of infection with A. actinomycetemcomitans and P. gingivalis than non-betel quid chewers. The association persists after adjusting for severity of the clinical parameters. In conclusion, betel quid chewing was associated with a higher prevalence of bleeding on probing where higher clinical levels of disease existed, and with a likelihood of subgingival infection with A. actinomycetemcomitans and P. gingivalis.

Immunohistochemical study of vestibular gingival blood vessel density and internal circumference in smokers and non-smokers

BACKGROUND

This study was undertaken to determine: 1) if sections stained with monoclonal antibody to CD34 can be used for measurement of gingival blood vessel density and circumference and 2) if long-term smoking affects either of these 2 parameters.

METHODS

Vestibular gingival biopsy samples were obtained from 17 adults (5 smokers and 12 non-smokers) who were undergoing routine periodontal surgery independently of this study. Hematoxylin and eosin staining was used for histological assessment of inflammation, while immunohistochemical staining with CD34 mouse monoclonal antibody was used to mark the endothelial cells of the blood vessels within each sample. Stringent selection criteria were applied to the 17 biopsy samples, and 7 (from 3 smokers and 4 non-smokers) were chosen to have their vascular density (number of vessels/unit area) and internal vessel circumference (IC) measured under a blinded protocol.

RESULTS

Repeated measurements of vascular density and internal circumference showed small standard deviations, indicating the high reproducibility of the measurement technique. The smoker group showed a higher proportion of small (IC < 50 microns) and a lower proportion of large blood vessels (IC > 100 microns), which was statistically significant (P = 0.0403 and P < 0.001, respectively). The difference between the vascular density of smokers and non-smokers was not significant (P = 0.092).

CONCLUSIONS

The present study indicates that the CD34 immunohistochemical staining technique is a simple and reproducible method for the measurement of density and internal circumference of gingival blood vessels. Based on this technique, cigarette smokers show a higher percentage of smaller blood vessels and a lower percentage of larger vessels, but similar vascular density, to non-smokers.

Cytokine gene expression in chronic periodontitis

BACKGROUND

Cytokines play an important rôle in controlling inflammatory processes and tissue homeostasis. Periodontitis, as any other chronic inflammatory disease, results from a disarrangement of host factors, mainly cytokines and the initiating agent. Modulation of the cytokines is not only controlled by the host but also by infecting bacteria and their products.

AIM

In the present study, we examined the cytokine mRNA expression profiles in six patients, each presenting sites affected with (1) severe progressive periodontitis, (2) chronic, but stable periodontal lesions, and (3) with healthy sites. Analysis using a quantitative RT-PCR included IFN-gamma, IL-1beta, IL-2, IL-4, IL-5, IL-6, and TNF-alpha.

MATERIAL AND METHODS

6 patients with chronic periodontitis were following treatment observed for a period of six years for local sites staying healthy, local sites with periodontal pathology but without signs of progression of attachment loss and sites with verified progression were biopsied. The biopsies were lyzed and analyzed for levels of cytokine mRNAs.

RESULTS

Results revealed considerable variation not only between patients, but also between individual sites. Each patient's site has thus to be looked at as an independent entity.

CONCLUSIONS

The local action of cytokines, which is heavily dependent on recruitment, interaction and activation of immunocompetent cells can explain the site-specific nature of cytokine expression. Cytokine data from individual sites together with the local clinical status and data from the literature demonstrate the complexity of periodontal disease pathogenesis. To gain insight to specific mechanisms further studies are needed.

Relationship between rheumatoid arthritis and periodontitis

BACKGROUND

Because of several similar features in the pathobiology of periodontitis and rheumatoid arthritis, in a previous study we proposed a possible relationship between the two diseases. Therefore, the aims of this study were to study a population of rheumatoid arthritis patients and determine the extent of their periodontal disease and correlate this with various indicators of rheumatoid arthritis.

METHODS

Sixty-five consecutive patients attending a rheumatology clinic were examined for their levels of periodontitis and rheumatoid arthritis. A control group consisted of age- and gender-matched individuals without rheumatoid arthritis. Specific measures for periodontitis included probing depths, attachment loss, bleeding scores, plaque scores, and radiographic bone loss scores. Measures of rheumatoid arthritis included tender joint analysis, swollen joint analysis, pain index, physician's global assessment on a visual analogue scale, health assessment questionnaire, levels of C-reactive protein, and erythrocyte sedimentation rate. The relationship between periodontal bone loss and rheumatological findings as well as the relationship between bone loss in the rheumatoid arthritis and control groups were analyzed.

RESULTS

No differences were noted for the plaque and bleeding indices between the control and rheumatoid arthritis groups. The rheumatoid arthritis group did, however, have more missing teeth than the control group and a higher percentage of these subjects had deeper pocketing. When the percentage of bone loss was compared with various indicators of rheumatoid arthritis disease activity, it was found that swollen joints, health assessment questionnaire scores, levels of C-reactive protein, and erythrocyte sedimentation rate were the principal parameters which could be associated with periodontal bone loss.

CONCLUSIONS

The results of this study provide further evidence of a significant association between periodontitis and rheumatoid arthritis. This association may be a reflection of a common underlying disregulation of the inflammatory response in these individuals.

Aspiration pneumonia: dental and oral risk factors in an older veteran population

OBJECTIVES

To investigate the importance of medical and dental factors in aspiration pneumonia in an older veteran population.

DESIGN

Prospective enrollment of subjects with retrospective analysis of data.

SETTING

Department of Veterans Affairs outpatient clinic, inpatient ward, and nursing home.

PARTICIPANTS

358 veterans age 55 and older; 50 subjects with aspiration pneumonia.

MEASUREMENTS

Demographic and medical data; functional status; health-related behaviors; dental care utilization; personal oral hygiene; comprehensive dental examination; salivary assays including IgA antibodies; and cultures of saliva, throat, and dental plaques.

RESULTS

Two logistic regression models produced estimates of significant risk factors. One model using dentate patients included: requiring help with feeding (odds ratio (OR) = 13.9), chronic obstructive pulmonary disease (COPD) (OR = 4.7), diabetes mellitus (OR = 3.5), number of decayed teeth (OR = 1.2), number of functional dental units (OR = 1.2), presence of important organisms for decay, Streptococcus sobrinus in saliva (OR = 6.2), and periodontal disease, Porphyromonous gingivalis in dental plaque (OR = 4.2), and Staphylococcus aureus presence in saliva (OR = 7.4). The second model, containing both dentate and edentulous patients included: requiring help with feeding (OR = 4.7), COPD (OR = 2.5), diabetes mellitus (OR = 1.7), and presence of S. aureus in saliva (OR = 8.3).

CONCLUSION

This study supports the significance of oral and dental factors while controlling for established medical risk factors in aspiration pneumonia incidence.

Oral health in the United States: the post-fluoride generation

Tremendous strides have been made in reducing the incidence of tooth decay, periodontal diseases, and associated loss of teeth in adults and children since the inception of community water fluoridation programs. Yet the disadvantaged and poor have not fully shared in the benefits. Other challenges to oral health remain. Oral cancer and related smoking and smokeless tobacco use remain major public health problems. Access to preventive and therapeutic dental care is far from universal. Public health programs similar in commitment to the approach of community water fluoridation programs initiated in the 1950s and 1960s are needed to address neglected oral health needs of underserved and high-risk populations in the United States.

Dental health and treatment needs among a sample of Bangladeshi medical users aged 40 years and over living in Tower Hamlets, UK

AIM

To assess the dental health status and treatment needs of Bangladeshi medical care users aged 40 years and over and to explore the relationship of oral disease status, tobacco usage and paan (betel quid) chewing.

DESIGN

Multi-centre cross-sectional study.

SETTING

General medical practitioners' waiting areas in Tower Hamlets, UK.

SUBJECTS

185 Bangladeshi adults aged 40 years and over.

INTERVENTION

A clinical examination and an interview schedule.

MEASURES

Dental status, periodontal status, dental plaque, calculus and denture status. Tobacco smoking and paan chewing behaviour.

RESULTS

The response rate was 74%. 85% of participants were dentate with an average number of 24 (SD +/- 5.4) standing teeth. The mean DMFT score was 5.38, with missing teeth (3.81) being the major component. The decayed component was 0.43 and the filled was 1.14. 46% of participants were assessed as being free from gingivitis. Significant relationships between chewing paan and aspects of dental and periodontal status were found. Impacts of oral health were reported by 45% of the respondents. The normative need for dental treatment was 96% with a perceived need of 48%.

CONCLUSION

There was considerable normative dental need. Whilst caries experience was low, there were high levels of periodontal treatment needs. Paan chewing was related to aspects of dental and periodontal status.

Environmental tobacco smoke and periodontal disease in the United States

OBJECTIVES

Cigarette smoking is a leading risk factor for periodontal disease. This cross-sectional study investigated the relation between environmental tobacco smoke (ETS) and periodontal disease in the United States.

METHODS

Data were obtained from the Third National Health and Nutrition Examination Survey (1988-1994). The outcome was periodontal disease, defined as 1 or more periodontal sites with attachment loss of 3 mm or greater and a pocket depth of 4 mm or greater at the same site. Exposure to ETS at home and work was self-reported. The study analyzed 6611 persons 18 years and older who had never smoked cigarettes or used other forms of tobacco.

RESULTS

Exposure to ETS at home only, work only, and both was reported by 18.0%, 10.7%, and 3.8% of the study population, respectively. The adjusted odds of having periodontal disease were 1.6 (95% confidence interval = 1.1, 2.2) times greater for persons exposed to ETS than for persons not exposed.

CONCLUSIONS

Among persons in the United States who had never used tobacco, those exposed to ETS were more likely to have periodontal disease than were those not exposed to ETS.

Classifications of oral lesions in HIV infection

BACKGROUND

Manifestations of immunosuppression may take the form of opportunistic infection, and neoplasia. While this paper has focused on gingival and periodontal manifestations. these tissues cannot be evaluated in isolation. The presence of involvement of other oral tissues such as the cheek or tongue with manifestations associated with HIV such as hairy leukoplakia, Kaposi's sarcoma at these sites, and candidiasis in addition to periodontal manifestations may further increase the clincal suspicion of underlying immunosuppression and/or progression of the immunosuppressive state.

DISCUSSION

The periodontist plays an essential r le in identifying the periodontal status of an individual and has an important r le to play in early recognition of signs and symptoms of HIV disease or progression of the medical condition.

CONCLUSION

Only through such recognition can appropriate definitive diagnostic testing be conducted, and appropriate therapeutic intervention for the oral condition and the systemic condition be considered.

Low-dose aspirin therapy and periodontal attachment loss in ex- and non-smokers

BACKGROUND, AIMS

This study investigated the periodontal status of non-smokers and ex-smokers in relation to their intake of low-dose aspirin.

METHODS

A self-selected sample of 392 males aged 50 years and over was recruited from the general population. Subjects were included in the study if they had a minimum of 6 or more natural teeth, took aspirin (300 mg or less per day) for at least 2 years and were either ex- or non-smokers. Controls were subjects who did not take aspirin regularly. A questionnaire was used to record demographic data, medical and dental histories. Individuals who had diabetes or other systemic diseases were excluded from the study. Periodontal attachment loss (PAL) was calculated by adding measurements of gingival recession and periodontal pocket depth made by a single examiner at 6 sites around each tooth using non-pressure sensitive periodontal probes. Plaque and gingival bleeding indices were also scored. Subjects were divided into 4 groups: aspirin non-smokers, aspirin ex-smokers, no aspirin non-smokers and no aspirin ex-smokers. Data were analysed using two-way ANOVA with age as the covariate. Severity and extent of mean PAL and the cumulative distribution of the mean of the most severe sites (MSS) of PAL were analysed.

RESULTS

Controlling for age, mean PAL in aspirin takers was significantly less 2.6+/-0.08 (se) mm than non-aspirin takers 2.9+/-0.06 (se) mm; this association was independent of smoking history. Ex-smokers had significantly more mean PAL 3.9+/-0.07 (se) mm than non-smokers 2.6+/-0.08 (se) mm, irrespective of aspirin status. When MSS-PAL was analysed, these differences became more pronounced; MSS-PAL in aspirin takers was significantly less 3.9+/-0.1 (se) mm than non-aspirin takers 4.2+/-0.08 (se) mm. Ex-smokers had significantly more MSS-PAL 4.3+/-0.08 (se) mm than non-smokers 3.8+/-0.08 (se) mm. Aspirin apparently had a protective association on PAL and it is hypothesised that low-dose aspirin may have reduced the rate of attachment loss.

CONCLUSIONS

This hypothesis needs to be confirmed by a prospective study. The results of this study suggest that individuals aged over 50 years, particularly ex-smokers, may benefit by taking low-doses of aspirin daily to reduce their risk of periodontal attachment loss.

Focus on primary care: periodontal disease: implications for women's health

A definite relationship is emerging between periodontal infections and systemic conditions. The objective of this review is to address this relationship as it pertains to cardiovascular disease and diabetes mellitus. Furthermore, because recent reports link the presence of periodontal disease to preterm delivery, the possible relationship between the development and progression of periodontal disease and certain hormonal states in women such as puberty, oral contraceptive use, menopause, and pregnancy will also be discussed. Although the current literature suggests a strong association between periodontal disease and a number of the discussed systemic conditions, causality can only be established with prospective studies. Intervention studies are needed to address how treatment effects the incidence and/or severity of periodontal disease-related systemic illness.

Nonsurgical periodontal therapy in 2000: a literature review

BACKGROUND

This article addresses the advantages and limitations of nonsurgical periodontal therapies to treat patients with mild-to-moderate chronic periodontitis.

TYPES OF STUDIES REVIEWED

Controlled clinical trials were selected that assessed the efficacy of the following treatment methods: mechanical instrumentation, ultrasonic débridement, supragingival irrigation, subgingival irrigation, local drug delivery, administration of systemic antibiotics and host-response modulation. Evidently, data with regard to alterations of probing depth, clinical attachment levels and inflammatory status were evaluated.

RESULTS

Comparison of the data from test and control groups revealed the following results. Manual and ultrasonic débridement can be used to treat most patients with mild-to-moderate chronic periodontitis. Patients who do not practice optimal plaque control can enhance their personal hygiene procedures by using supragingival irrigation. Subgingival irrigation usually does not provide any benefit beyond that achieved with root planing. Systemic and locally delivered antimicrobial agents appear to be most beneficial among patients who do not respond to conventional treatment. Host modulation may enhance root planing modestly.

CLINICAL IMPLICATIONS

The data indicate that most patients with mild-to-moderate periodontitis can be treated with nonsurgical therapies. However, clinicians need to be aware of the limitations of each technique with regard to the magnitude of improvement that it can induce at specific sites.

Herpesviruses: a unifying causative factor in periodontitis?

Human cytomegalovirus and Epstein-Barr virus type 1 are discussed in this review as they relate to destructive periodontal disease in humans. Genomes of the two herpesviruses occur frequently in severe adult periodontitis, localized and generalized juvenile periodontitis, Papillon-Lefèvre syndrome periodontitis, Down's syndrome periodontitis, HIV-associated periodontitis and acute necrotizing ulcerative gingivitis. Herpesvirus infections generally involve a mild or asymptomatic primary phase followed by an asymptomatic latent phase interrupted sporadically by periods of activation, where viral replication and possibly clinical disease become manifest. Herpesvirus reactivation is triggered by a number of immunosuppressing factors, some of which have also been shown to be risk indicators of periodontal disease. Available evidence argues for the involvement of active cytomegalovirus infection in the initiation and progression of localized juvenile periodontitis and possibly other types of periodontal disease. In periodontal disease, herpesviruses may cause release of tissue-destructive cytokines, overgrowth of pathogenic periodontal bacteria, and initiation of cytotoxic or immunopathogenic events. Understanding the significance of herpesviruses in the causation and pathogenesis of destructive periodontal diseases may have important implications in future prevention and treatment of the diseases.

Metabolic diseases and their possible link to risk indicators of periodontitis

BACKGROUND

During the last few years, risk assessment has become one of the main topics of periodontal research. Therefore, the aim of this study was to determine whether a predisposition to metabolic disorders such as diabetes mellitus (in the absence of diagnosed diabetic disease) or hyperlipidemia may be risk indicators for periodontitis.

METHODS

One hundred patients ranging in age from 40 to 70 years were examined. The patients were classified as having impaired glucose tolerance (IGT) but no manifest diabetes (56 patients), hyperlipidemia (17 patients, HL), or normal metabolic status (27 control patients). Probing depth (PD), attachment level (AL), plaque index (PI), and gingival bleeding on probing (BOP) were recorded. Serum antibody titers (SAT) to A. actinomycetemcomitans (A.a.), P. intermedia (P.i.), and P. gingivalis (P.g.) were determined by enzyme-linked immunosorbent assay (ELISA). Pooled subgingival plaque samples were analyzed using indirect immunofluorescence to detect the same organisms. In addition, respiratory burst activity of peripheral polymorphonuclear leukocytes (PMN) was evaluated by chemiluminescence (CL).

RESULTS

No significant differences were observed between the IGT group and normal controls in the following parameters: 1) percentage of sites exhibiting BOP; 2) mean PI; 3) mean PD and AL; 4) percentage of periodontal microorganisms; and 5) increased SAT. The IGT probands exhibited a significantly higher mean serum level of triglycerides, as well as higher formyl-methionyl-leucyl-phenylalanine (FMLP)-stimulated PMN chemiluminescence than the control group. Patients with hyperlipidemia (HL) showed a significantly higher number of sextants with increased PD (73.4%) than the control group (50.6%). Similar results were obtained when comparing the percentage of all sites with increased PD (HL = 16.7%, control 12.3%). The mean FMLP-stimulated CL in patients with hyperlipidemia was significantly higher than the control group. When looking at all patients, there was a small but statistically significant correlation between PD and lipid levels. In addition, a significant correlation was observed between lipid serum levels and the FMLP-stimulated chemiluminescence.

CONCLUSIONS

These findings suggest that abnormal glucose tolerance, which is a predisposing factor for diabetes mellitus, does not appear to be a risk indicator for periodontal disease. On the other hand, impaired lipid metabolism does seem to be a risk indicator for periodontitis.

Smoking-attributable periodontitis in the United States: findings from NHANES III. National Health and Nutrition Examination Survey

BACKGROUND

The principal objectives of this study were to examine the relationship between cigarette smoking and periodontitis and to estimate the proportion of periodontitis in the United States adult population that is attributable to cigarette smoking.

METHODS

Data were derived from the Third National Health and Nutrition Examination Survey, a nationally representative multipurpose health survey conducted in 1988 to 1994. Participants were interviewed about tobacco use and examined by dentists trained to use standardized clinical criteria. Analysis was limited to dentate persons aged > or =18 years with complete clinical periodontal data and information on tobacco use and important covariates (n = 12,329). Data were weighted to provide U.S. national estimates, and analyses accounted for the complex sample design. We defined periodontitis as the presence of > or =1 site with clinical periodontal attachment level > or =4 mm apical to the cemento-enamel junction and probing depth > or =4 mm. Current cigarette smokers were those who had smoked > or =100 cigarettes over their lifetime and smoked at the time of the interview; former smokers had smoked > or =100 cigarettes but did not currently smoke; and never smokers had not smoked > or =100 cigarettes in their lifetime.

RESULTS

We found that 27.9% (95% confidence interval [CI]: +/-1.8%) of dentate adults were current smokers and 23.3% (95% CI: +/-1.2%) were former smokers. Overall, 9.2% (95% CI: +/-1.4%) of dentate adults met our case definition for periodontitis, which projects to about 15 million cases of periodontitis among U.S. adults. Modeling with multiple logistic regression revealed that current smokers were about 4 times as likely as persons who had never smoked to have periodontitis (prevalence odds ratio [ORp] = 3.97; 95% CI, 3.20-4.93), after adjusting for age, gender, race/ethnicity, education, and income:poverty ratio. Former smokers were more likely than persons who had never smoked to have periodontitis (ORp = 1.68; 95% CI, 1.31-2.17). Among current smokers, there was a dose-response relationship between cigarettes smoked per day and the odds of periodontitis (P <0.000001), ranging from ORp = 2.79 (95% CI, 1.90-4.10) for < or =9 cigarettes per day to ORp = 5.88 (95% CI, 4.03-8.58) for > or =31 cigarettes per day. Among former smokers, the odds of periodontitis declined with the number of years since quitting, from ORp = 3.22 (95% CI, 2.18-4.76) for 0 to 2 years to ORp = 1.15 (95% CI, 0.83-1.60) for > or =11 years. Applying standard epidemiologic formulas for the attributable fraction for the population, we calculated that 41.9% of periodontitis cases (6.4 million cases) in the U.S. adult population were attributable to current cigarette smoking and 10.9% (1.7 million cases) to former smoking. Among current smokers, 74.8% of their periodontitis was attributable to smoking.

CONCLUSIONS

Based on findings from this study and numerous other reports, we conclude that smoking is a major risk factor for periodontitis and may be responsible for more than half of periodontitis cases among adults in the United States. A large proportion of adult periodontitis may be preventable through prevention and cessation of cigarette smoking.

Characteristics of dental emergency clinic patients with and without disabilities

This study compared oral health and demographic characteristics of patients with and without disabilities at a dental school emergency clinic. Of 407 consecutive patients surveyed, 20.4% reported disabilities. Two groups matched by age and gender, those with disabilities (DIS, n = 79) and those without disabilities (ND, n = 177), were compared on questionnaire responses; two subgroups, DIS (n = 38) and ND (n = 44), were assessed clinically. The mean ages of the DIS and ND groups were 44.0 years (SD +/- 11.6) and 43.0 years (SD +/- 12.3), respectively. By chi-squared analysis, DIS vs. ND subjects had significantly lower levels of education, employment, income, and dental insurance, and greater dependence on Government funding. In the DIS group, 79.5% were not working, while 6.4% did work regularly. In the ND group, the corresponding values were 30.9% and 46.9%, respectively. In the DIS group, 51.9% identified Medicaid acceptance as the reason they sought care at the clinic, while 62.7% of the subjects in the ND group identified the lower fee structure as the reason for clinic selection. More DIS than ND subjects reported dentists' unavailability and inability to manage the disability, lack of transportation, effect of dental problems on health, and referral by a health professional. DIS vs. ND subjects had significantly fewer sound teeth and more missing teeth. The results suggest that one in five dental school emergency clinic patients has disabilities.

Milestones in periodontal research and the remaining critical issues

A significant recent development in periodontal research has been the convergence of basic and clinical research resulting in a logarithmic increase in the rate of progress. Scientific consensus has been reached in many areas. In most populations, moderate to severe periodontitis affects a relatively small segment of adults who are at high risk. The microbial etiology is accepted and the identity of the major pathogenic bacterial species is known. The mechanisms through which resistant individuals successfully fend off the microbial challenge are known, and the immuno-inflammatory pathways activated by bacteria that underlie destruction of the alveolar bone and the connective tissues of the periodontium are reasonably well understood. The evidence shows that these pathways are held in common by all forms of periodontitis. Therapeutic modulation of these pathways is now possible, and new treatments based on such modulation are now becoming available. Although bacteria are essential for disease to occur, they are insufficient; a susceptible host is also necessary. Host susceptibility, disease progression and response to treatment are determined predominantly by heredity and environmental and acquired risk factors. Some of these can be changed while others are immutable. Concepts and procedures for treatment are generally scientifically based and appropriately applied. Preventive measures are largely successful and widely practiced in industrialized countries. Clearly, control of these ancient chronic diseases is now within our reach. In spite of the tremendous progress, many unresolved issues remain. The purpose of this paper is to summarize some of the major accomplishments of periodontal research, and identify and discuss some of the more important critical issues that still need to be addressed.

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.

Risk indicators for harboring periodontal pathogens

The risk for harboring 6 putative periodontal pathogens in 4 selected periodontal pockets, in whole saliva, or in either site (i.e., orally) was determined in 52 Caucasians, 49 African-Americans, 48 Asian-Americans, and 50 Hispanics living in Los Angeles. 16S rRNA PCR analysis assessed the presence of Actinobacillus actinomycetemcomitans, Bacteroides forsythus, Porphyromonas gingivalis, Prevotella intermedia, Prevotella nigrescens, and Treponema denticola. Step-wise regression analysis determined the relationship between the occurrence of each organism and various explanatory variables (risk indicators). Periodontal probing depth or disease severity was positively associated with all 6 study organisms. African-Americans carried an increased risk for harboring P. gingivalis in saliva (odds ratio [OR] 2.95) and orally (OR 2.66), and a reduced risk for harboring T. denticola orally (OR 0.34). Asian-Americans showed an increased risk for harboring A. actinomycetemcomitans in periodontal pockets (OR 6.63) and P. gingivalis in periodontal pockets (OR 5.39), in saliva (OR 5.74), and orally (OR 5.81). Hispanics demonstrated an increased risk for harboring A. actinomycetemcomitans in periodontal pockets (OR 12.27) and P. gingivalis in periodontal pockets (OR 6.07), in saliva (OR 8.72), and orally (OR 7.98). Age was positively associated with the prevalence of P. gingivalis in saliva (OR 1.20) and orally (OR 1.20), and of A. actinomycetemcomitans orally (OR 1.18). The male gender was a risk factor for harboring P. intermedia in periodontal pockets (OR 2.40), in saliva (OR 3.31), and orally (OR 4.25), and for harboring P. nigrescens in saliva (OR 2.85). The longer the subjects resided in the United States, the less likely A. actinomycetemcomitans was detected orally (OR 0.82). Former smokers demonstrated a decreased risk for harboring A. actinomycetemcomitans in saliva (OR 0.23). Current smokers displayed an increased risk for harboring T. denticola in periodontal pockets (OR 4.61). The number of dental visits in the past 10 years was inversely related to the prevalence of P. intermedia orally (OR 0.96). The prevalence of P. intermedia in saliva was positively associated with the length of time from the last dental visit (OR 1.01). This study suggests that genetic and/or environmental factors predispose subjects to oral colonization by putative periodontal pathogens.

The periodontal disease problem. A comparison between industrialised and developing countries

There is no reason to believe that periodontal diseases in industrialised and developing countries are in principle different. That is, not in the sense that the problem is caused by a different set of periodontal diseases, with different micro-organisms and a different natural history, needing a different approach towards prevention and treatment. Indeed, from a public health perspective the relative similarities in periodontal conditions around the world are far more striking than the differences. The view that periodontal diseases are a much more prevalent and a severe problem in the developing countries seems to be true only in terms of poorer oral hygiene and considerably greater calculus retention, already at a young age, but not so clear for periodontal destruction in adults.

GTR therapy of intrabony defects using 2 different bioresorbable membranes: 12-month results

This prospective split-mouth study was designed to compare the clinical and radiographic healing results in intrabony periodontal defects 12 months after GTR therapy with 2 different bioresorbable barriers. The study comprised 25 healthy patients with one pair of contralaterally located intrabony defects with a probing pocket depth of > or = 6 mm and radiographic evidence of angular bone loss of > or = 4 mm. The 2 defects of each patient were randomized for treatment either with polylactic acid (PLA) membranes or with polyglactin-910 (PG-910) membranes. The patients received systemic doxycycline (100 mg/d) for 11 days postoperatively. One blinded examiner recorded the following clinical parameters using a pressure calibrated probe at baseline and after 12 months: papillary bleeding index (PBI), gingival recession (REC), probing pocket depth (PPD), and probing attachment level (PAL). The vertical relative attachment gain (V-rAG) was calculated as a % of the PAL gain related to the maximum possible attachment gain (expressed by the intraoperatively measured depth of the osseous defect). Geometrically standardized intraoral radiographs were quantitatively evaluated for bone changes (density, area) in the defect region using digital subtraction radiography (DSR). Clinical and radiographic data were statistically analyzed using the Wilcoxon-signed-rank test (alpha=0.05). Postoperative membrane exposures occurred in 9 PLA and 13 PG-910 treated sites. After 12 months of healing, both barrier types provided significant PPD reductions and PAL gain [median (25/75 percentile)]: deltaPPD [PLA: 3.0 (2.0/4.0) mm; PG-910: 3.0 (2.0/4.5) mm]; deltaPAL [PLA: 3.0 (2.5/4.0) mm; PG-910: 2.0 (1.0/4.0) mm]. V-rAG amounted to 60% in PLA sites and 54% in PG-910 sites. DSR revealed significant bone density gain after 12 months. 58.3% of the initial defect area in PLA sites and 54.0% of the initial defect area in PG-910 sites showed bone density gain. Neither clinical nor radiographic data revealed any significant difference between the 2 barrier types after 12 months. In conclusion, this 12-month study demonstrated that PLA and PG-910 membranes provided similar favorable regeneration results in deep intrabony periodontal defects.