A study of attachment loss patterns in survivor teeth at 18 months, 36 months and 5 years in community-dwelling older adults

Periodontal profile classes predict periodontal disease progression and tooth loss

BACKGROUND

Current periodontal disease taxonomies have limited utility for predicting disease progression and tooth loss; in fact, tooth loss itself can undermine precise person-level periodontal disease classifications. To overcome this limitation, the current group recently introduced a novel patient stratification system using latent class analyses of clinical parameters, including patterns of missing teeth. This investigation sought to determine the clinical utility of the Periodontal Profile Classes and Tooth Profile Classes (PPC/TPC) taxonomy for risk assessment, specifically for predicting periodontal disease progression and incident tooth loss.

METHODS

The analytic sample comprised 4,682 adult participants of two prospective cohort studies (Dental Atherosclerosis Risk in Communities Study and Piedmont Dental Study) with information on periodontal disease progression and incident tooth loss. The PPC/TPC taxonomy includes seven distinct PPCs (person-level disease pattern and severity) and seven TPCs (tooth-level disease). Logistic regression modeling was used to estimate relative risks (RR) and 95% confidence intervals (CI) for the association of these latent classes with disease progression and incident tooth loss, adjusting for examination center, race, sex, age, diabetes, and smoking. To obtain personalized outcome propensities, risk estimates associated with each participant's PPC and TPC were combined into person-level composite risk scores (Index of Periodontal Risk [IPR]).

RESULTS

Individuals in two PPCs (PPC-G: Severe Disease and PPC-D: Tooth Loss) had the highest tooth loss risk (RR = 3.6; 95% CI = 2.6 to 5.0 and RR = 3.8; 95% CI = 2.9 to 5.1, respectively). PPC-G also had the highest risk for periodontitis progression (RR = 5.7; 95% CI = 2.2 to 14.7). Personalized IPR scores were positively associated with both periodontitis progression and tooth loss.

CONCLUSIONS

These findings, upon additional validation, suggest that the periodontal/tooth profile classes and the derived personalized propensity scores provide clinical periodontal definitions that reflect disease patterns in the population and offer a useful system for patient stratification that is predictive for disease progression and tooth loss.

Derivation and Validation of the Periodontal and Tooth Profile Classification System for Patient Stratification

BACKGROUND

The goal of this study is to use bioinformatics tools to explore identification and definition of distinct periodontal and tooth profile classes (PPCs/TPCs) among a cohort of individuals by using detailed clinical measures at the tooth level, including both periodontal measurements and tooth loss.

METHODS

Full-mouth clinical periodontal measurements (seven clinical parameters) from 6,793 individuals from the Dental Atherosclerosis Risk in Communities Study (DARIC) were used to identify PPC. A custom latent class analysis (LCA) procedure was developed to identify clinically distinct PPCs and TPCs. Three validation cohorts were used: NHANES (2009 to 2010 and 2011 to 2012) and the Piedmont Study population (7,785 individuals).

RESULTS

The LCA method identified seven distinct periodontal profile classes (PPCs A to G) and seven distinct tooth profile classes (TPCs A to G) ranging from health to severe periodontal disease status. The method enabled identification of classes with common clinical manifestations that are hidden under the current periodontal classification schemas. Class assignment was robust with small misclassification error in the presence of missing data. The PPC algorithm was applied and confirmed in three distinct cohorts.

CONCLUSIONS

The findings suggest PPC and TPC using LCA can provide robust periodontal clinical definitions that reflect disease patterns in the population at an individual and tooth level. These classifications can potentially be used for patient stratification and thus provide tools for integrating multiple datasets to assess risk for periodontitis progression and tooth loss in dental patients.

Long-term regular dental attendance and periodontal disease in the 1998 adult dental health survey

AIM

The aim of this study was to explore the association between long-term pattern of dental attendance and periodontal disease among British adults.

METHODS

We used data from 3272 adults who participated in the 1998 Adult Dental Health Survey in the UK. Participants were classified into four trajectories (current, always, former and never regular attenders) based on their responses to three questions on lifetime dental attendance patterns. The numbers of teeth with pocket depth (PD) ≥4 mm and loss of attachment (LOA) ≥4 mm were the outcome measures. The association between dental attendance patterns and each periodontal measure was assessed in crude and adjusted models using negative binomial regression.

RESULTS

Never and former regular attenders had more teeth with PD ≥4 mm (Rate Ratios with 95% Confidence Interval: 1.58 [1.28-1.95] and 1.34 [1.12-1.60] respectively) and LOA ≥4 mm (1.34 [1.04-1.72] and 1.37 [1.07-1.75] respectively) than always regular attenders, after adjustments for demographic (sex, age and country of residence) and socioeconomic factors (education and social class). However, no differences in periodontal measures were found between always and current regular attenders.

CONCLUSION

This analysis of national cross-sectional data shows that adults with different long-term patterns of dental attendance have different periodontal health status.

Cluster adjusted regression for displaced subject data (CARDS): Marginal inference under potentially informative temporal cluster size profiles

Ignorance of the mechanisms responsible for the availability of information presents an unusual problem for analysts. It is often the case that the availability of information is dependent on the outcome. In the analysis of cluster data we say that a condition for informative cluster size (ICS) exists when the inference drawn from analysis of hypothetical balanced data varies from that of inference drawn on observed data. Much work has been done in order to address the analysis of clustered data with informative cluster size; examples include Inverse Probability Weighting (IPW), Cluster Weighted Generalized Estimating Equations (CWGEE), and Doubly Weighted Generalized Estimating Equations (DWGEE). When cluster size changes with time, i.e., the data set possess temporally varying cluster sizes (TVCS), these methods may produce biased inference for the underlying marginal distribution of interest. We propose a new marginalization that may be appropriate for addressing clustered longitudinal data with TVCS. The principal motivation for our present work is to analyze the periodontal data collected by Beck et al. (1997, Journal of Periodontal Research 6, 497-505). Longitudinal periodontal data often exhibits both ICS and TVCS as the number of teeth possessed by participants at the onset of study is not constant and teeth as well as individuals may be displaced throughout the study.

Biomarkers of periodontitis and inflammation in ischemic stroke: A case-control study

Periodontitis is a common infectious disease associated with increased risk for ischemic stroke though presently unclear mechanisms. In a case-control study, we investigated salivary levels of four periodontal pathogens, as well as systemic and local inflammatory markers. The population comprised 98 patients with acute ischemic stroke (mean ± SD, 68.2 ± 9.7 yrs; 45.9% women) and 100 healthy controls (69.1 ± 5.2 yrs; 47.0% women). Patients were more often edentulous and had fewer teeth than controls (13.8 ± 10.8 versus 16.6 ± 10.1). After adjusting for stroke risk factors and number of teeth, controls had higher saliva matrix metalloproteinase-8 (MMP-8), myeloperoxidase (MPO), IL-1β, Aggregatibacter actinomycetemcomitans, and serum LPS activity levels. Patients had higher serum MMP-8 and MPO, and they were more often qPCR-positive for A. actinomycetemcomitans (37.9% versus 19.0%) and for ≥3 periodontopathic species combined (50.0% versus 33.0%). We conclude that controls more often had evidence of current periodontal infection with higher periodontal pathogen amount, endotoxemia, local inflammation and tissue destruction. Stroke patients more often had evidence of end-stage periodontitis with edentulism and missing teeth. They were more often carriers of several periodontopathic pathogens in saliva, especially A. actinomycetemcomitans. Additionally, inflammatory burden may contribute to high systemic inflammation associated with elevated stroke susceptibility.

Association of oral health and cardiovascular disease risk factors "results from a community based study on 5900 adult subjects"

Objectives. This study aimed to determine the association between some oral health status as a risk factor for cardiac diseases and other cardiovascular disease (CVD) risk factors in a sample of Iranian population in 2011. Methods. The study recruited 5900 inhabitants who aged 15–75 years old of Kerman city through a population based cluster sampling. Having collected informed consent, participants were interviewed for CVD risk factors. Some oral health indicators such as DMFT, Gingival Inflammation index, and Community Periodontal Index were assessed. The association between oral health indices and CVD risk factors was tested using multivariate regression models. Results. The mean age of participants was 33.5 years, and 45.1% were male. Moderate gingival inflammation was observed in 67.6% of participants. Presence of sub- or supragingival calculus was more common (90%) in participants. Older age (RR from 2.7 to 3.88), cigarette smoking (RR = 1.49), and high blood glucose (RR = 1.41) showed an increased risk for oral diseases after adjustment for different covariates including established CVD risk factors. Conclusion. The study results showed an increase in periodontal diseases in the presence of some CVD risk factors. Therefore there may be a bilateral but independent association for both conditions and common risk factor approach preventive program is highly recommended.

ASC-dependent RIP2 kinase regulates reduced PGE2 production in chronic periodontitis

Levels of prostaglandin E(2) (PGE(2)) and its processing enzyme, prostaglandin-endoperoxide-synthase-2/ cyclooxygenase-2 (PTGS2/COX-2), are elevated in actively progressing periodontal lesions, but suppressed in chronic disease. COX-2 expression is regulated through inflammatory signaling that converges on the mitogen-activated protein kinase (MAPK) pathway. Emerging evidence suggests a role for the inflammatory adaptor protein, ASC/Pycard, in MAPK activation. We postulated that ASC may represent a mediator of the MAPK-mediated regulatory network of PGE(2) production. Using RNAi-mediated gene slicing, we demonstrated that ASC regulates COX-2 expression and PGE(2) production in THP1 monocytic cells following infection with Porphyromonas gingivalis (Pg). Production of PGE(2) did not require the inflammasome adaptor function of ASC, but was dependent on MAPK activation. Furthermore, the MAP kinase kinase kinase CARD domain-containing protein RIPK2 was induced by Pg in an ASC-dependent manner. Reduced ASC and RIPK2 levels were revealed by orthogonal comparison of the expression of the RIPK family in ASC-deficient THP1 cells with that in chronic periodontitis patients. We show that pharmacological inhibition of RIPK2 represses PGE(2) secretion, and RNAi-mediated silencing of RIPK2 leads to diminished MAPK activation and PGE(2) secretion. These findings identify a novel ASC-RIPK2 axis in the generation of PGE(2) that is repressed in patients diagnosed with chronic adult periodontitis.

Pattern and rate of progression of periodontal attachment loss in an urban population of South Brazil: a 5-years population-based prospective study

AIM

The aim of this 5-years longitudinal study was to investigate the pattern and rate of periodontal attachment loss (PAL) progression in an urban population in South Brazil.

METHODS

In 2001, a multistage probability sampling strategy was used to derive a representative sample of 1,465 dentate individuals from Porto Alegre, Brazil. Five years later, 697 dentate individuals (294M/403F, mean age: 37.9 ± 13.3) were available for follow-up. PAL was assessed by calibrated examiners using a full-mouth protocol. Estimates of proximal PAL progression and standard errors (SE) are reported.

RESULTS

Fifty-six per cent (SE: 1.9) and 36% (SE: 1.8) of subjects showed PAL progression ≥3 mm affecting ≥2 and ≥4 teeth respectively. PAL progression ≥3 mm was mostly localized affecting 3.8 (SE: 0.2) teeth and 5.7 (SE: 0.3) sites. Annual PAL progression was, on average, 0.3 mm (SE: 0.01). Significant differences in PAL progression were observed according to age, gender, race and socioeconomic status. PAL progression increased with age reaching the highest progression rate in the 40-49 years cohort, and then decreased in older age groups. PAL progression was consistently higher among males and non-Whites than females and whites.

CONCLUSION

A large proportion of this urban Brazilian sample was affected by PAL progression underscoring the need for health promotion initiatives aiming at preventing progression of destructive periodontal disease.

Alteration of PTGS2 promoter methylation in chronic periodontitis

Levels of prostaglandin E(2) and the prostaglandin-endoperoxide synthase-2 (PTGS2, or COX-2) increase in actively progressing periodontal lesions, but decrease in chronic disease. We hypothesized that chronic inflammation is associated with altered DNA methylation levels within the PTGS2 promoter, with effects on COX-2 mRNA expression. PTGS2 promoter methylation levels from periodontally inflamed gingival biopsies showed a 5.06-fold increase as compared with non-inflamed samples (p = 0.03), and the odds of methylation in a CpG site in the inflamed gingival group is 4.46 times higher than in the same site in the non-inflamed group (p = 0.016). The level of methylation at -458 bp was inversely associated with transcriptional levels of PTGS2 (RT-PCR) (p = 0.01). Analysis of the data suggests that, in chronically inflamed tissues, there is a hypermethylation pattern of the PTGS2 promoter in association with a lower level of PTGS2 transcription, consistent with a dampening of COX-2 expression in chronic periodontitis. These findings suggest that the chronic persistence of the biofilm and inflammation may be associated with epigenetic changes in local tissues at the biofilm-gingival interface.

Clinical characteristics and microbiota of progressing slight chronic periodontitis in adults

AIM

This study sought clinical and microbial risk indicators for progressing slight periodontitis.

MATERIAL AND METHODS

One hundred and seventeen periodontally healthy or slight periodontitis adults (20-40 years) were monitored clinically at 6-month intervals followed by supragingival cleaning. Inter-proximal sites with >1.5 mm increase in clinical attachment over 18 months were considered disease active. Subgingival plaque was analysed by 78 16S rDNA and 38 whole-genomic DNA probes and by PCR to Porphyromonas gingivalis and Tannerella forsythia. Characteristics were compared between active and inactive subjects.

RESULTS

Twenty-two subjects showed disease activity principally at molars. Mean baseline gingival and plaque indices, bleeding on probing, probing depth and clinical attachment level (CAL) were higher in active subjects. DNA probes detected species and not-yet-cultivated phylotypes from chronic periodontitis, although few species were associated with active subjects. By PCR P. gingivalis (p=0.007) and T. forsythia (p=0.075) were detected more frequently during monitoring in active subjects. Stepwise logistic analysis associated baseline levels of gingival index, clinical attachment and bleeding with subsequent clinical attachment loss.

CONCLUSIONS

Gingivitis and CAL were significantly associated with progressing slight periodontitis in 20--40-year-old adults. Species associated with moderate and advanced chronic periodontitis were detected in slight periodontitis.

Comparative Efficacy of Stabilized Stannous Fluoride/Sodium Hexametaphosphate Dentifrice and Sodium Fluoride/Triclosan/Copolymer Dentifrice for the Prevention of Periodontitis in Xerostomic Patients: A 2-Year Randomized Clinical Trial

BACKGROUND

The primary objective of this study was to compare the efficacy of a stannous fluoride (SnF2) dentifrice relative to a positive control triclosan dentifrice for prevention of clinical attachment loss (CAL) in xerostomic patients. A secondary objective was to compare the dentifrices for root caries remineralization.

METHODS

This was a 2-year, randomized, double-masked, parallel-group study. A 0.454% SnF2/sodium hexametaphosphate dentifrice was tested versus a positive control dentifrice (sodium fluoride/0.30% triclosan/copolymer) in 440 medication-induced xerostomic adults identified in a 1-year, run-in phase (no treatment) as high risk for periodontitis and root caries. During the study phase, subjects were stratified based on gender and attachment level into two groups. Subjects brushed twice a day for 60 seconds using their assigned product. Clinical examinations including probing depth, attachment level, bleeding on probing, and root caries remineralization were performed at baseline and 1 and 2 years.

RESULTS

A total of 334 subjects were evaluable. During run-in, average CAL relative to initial examination was 1.33 mm. Probing depth increased 0.95 mm. At year 2 in the treatment phase, attachment gain was 0.77 mm for the test group and 0.79 mm for the control group versus baseline. Probing depth decreased 0.57 mm for the test group, similar to the control group (0.53 mm). These changes versus baseline were statistically significant (P <0.01) for each group. Products were not statistically significantly different from each other. Both treatments resulted in similar remineralization for root caries lesions at study completion (P = 0.40).

CONCLUSION

The results establish comparable benefits for the SnF2 dentifrice in preventing CAL and root caries versus the sodium fluoride/triclosan/copolymer control in xerostomic patients.

Incidence of Periodontal Attachment Loss over 8 to 10 Years among Iowa Elders Aged 71+ at Baseline

OBJECTIVES

There has been limited research on the long-term incidence of periodontal attachment loss (ALOSS) among adults aged 70 and older. This study investigated periodontal ALOSS incidence among elderly Iowans aged 71 and older over an 8- to 10-year period.

METHODS

Clinical examination data were obtained for a cohort of the Iowa 65+ Oral Health Study/Oral Lesion Detection Study in 1988 (baseline) and again in 1996-98. Periodontal measurements, including gingival recession and probing depth, were made by trained examiners at both exams for each retained tooth at buccal (B) and mesiobuccal (MB) sites. Paired-sample t-tests were used to determine whether significant differences existed in ALOSS between the two time points; two-sample t-tests were used to assess the significance between genders and age groups (81 to 85 versus 86 to 93 years at follow-up).

RESULTS

Of the 77 individuals examined at baseline, 35 provided longitudinal data for a total of 705 retained teeth. The data revealed that there were significant changes in ALOSS at B, MB, and combined sites during the observation period, but there were no significant differences in ALOSS by gender or age group. The mean differences in ALOSS between the two time periods were 0.57mm (SD = 0.69, Max = 2.08) at B sites, and 0.43mm (SD = 0.63, Max = 2.00) at MB sites. Over the period of 8 to 10 years, 2+ mm ALOSS incidence occurred at 17.6 percent of B sites and 13.9 percent of MB sites. Also, 68.6, 71.4, and 82.9 percent of the subjects experienced ALOSS incidence of 2+ mm at one or more B, MB, and B or MB sites, respectively, while 20.0, 25.7, and 31.4 percent of the subjects experienced ALOSS incidence of 4+ mm at one or more B, MB, and B or MB sites, respectively.

CONCLUSIONS

Continuing ALOSS incidence was common in this elderly population. This study suggests that periodontal treatment continues to be important for the elderly.

Analytical epidemiology of periodontitis

AIMS

To review the literature related to the analytical epidemiology of periodontitis generated over the past decade. This review does not deal with descriptive epidemiologic studies of the prevalence, extent and severity of periodontitis with respect to global geography, but focuses exclusively on analytical epidemiology issues, including the challenges posed by the use of different case definitions across studies, current theories and models of disease progression, and risk factors associated with the onset and progression of periodontitis.

METHODS

Relevant publications in the English language were identified after Medline and PubMed database searches.

FINDINGS AND CONCLUSIONS

There is a conspicuous lack of uniformity in the definition of periodontitis used in epidemiologic studies, and findings from different research groups are not readily interpretable. There is a lack of studies that specifically address the distinction between factors responsible for the onset of periodontitis versus those affecting its progression. Colonization by specific bacteria at high levels, smoking, and poorly controlled diabetes have been established as risk factors for periodontitis, while a number of putative factors, including specific gene polymorphisms, have been identified in association studies. There is a clear need for longitudinal prospective studies that address hypotheses emerging from the cross-sectional data and include established risk factors as covariates along with new exposures of interest. Intervention studies, fulfilling the "targeting" step of the risk assessment process, are particularly warranted. Obvious candidates in this context are studies of the efficacy of elimination of specific bacterial species and of smoking cessation interventions as an alternative to the traditional broad anti-plaque approach in the prevention and control of periodontitis. Ideally, such studies should have a randomized-controlled trial design.

Forty-Eight–Month Periodontal Attachment Loss Incidence in a Population-Based Cohort Study: Role of Baseline Status, Incident Tooth Loss, and Specific Behavioral Factors

BACKGROUND

The objectives of this study were to: 1) test hypotheses that behavioral factors, baseline clinical status, and incident tooth loss are significantly associated with attachment loss incidence (ALI) and 2) quantify the effect of incident tooth loss on conclusions made about ALI.

METHODS

The Florida Dental Care Study was a prospective study of persons > or =45 years old. In-person interviews and examinations were conducted at baseline and 48 months, with telephone interviews in between.

RESULTS

Of 560 persons with baseline and 48-month examinations, 22% of persons and 1.8% of teeth had ALI. This was highest among persons with no dental visit during follow-up (person-level incidence of 46%; 5.0% tooth-level incidence). Statistically significant covariates in a multivariable regression of ALI were: losing a tooth due to periodontal reasons after baseline, but before the 48-month examination; not receiving a dental cleaning; and baseline factors (worst attachment level of > or =7 mm, not flossing, a molar tooth, current smoker).

CONCLUSIONS

A substantial percentage of persons experienced ALI. Baseline attachment level and behavioral factors were significantly associated with ALI. Persons with incident tooth loss were also at increased risk for ALI, and teeth lost during follow-up had worse baseline attachment level. Had these teeth not been lost before the final examination, the ALI estimate could only have been higher. These findings demonstrate that those at greatest risk for ALI are least likely to enter the dental care system, and among those who do, one health outcome (tooth loss) can affect conclusions made about the incidence of another (ALI).

Incidence of periodontal attachment loss over 5 years among older South Australians

OBJECTIVES

This study described the 5-year incidence of periodontal attachment loss (ALOSS) among older Australians.

MATERIAL AND METHOD

Clinical examination data were obtained at baseline and 5 years from participants in a cohort study of South Australians aged 60+. Periodontal measurements (gingival recession, GR; probing depth, PD) were made for each tooth at 3 sites. An incident case of ALOSS was identified as an individual having 2+ sites with 3+ mm ALOSS.

RESULTS

Some 342 (42.7%) of the 801 individuals examined at baseline were re-examined after 5 years, contributing longitudinal data from a total of 15,522 sites (6102 in the maxilla and 9420 in the mandible). Most sites showed no change in either GR or PD. Using a threshold of 3+ mm for change, ALOSS occurred at 2.3% of mesiobuccal sites, 2.5% of buccal sites, and 3.4% of distolingual sites. Distolingual sites on molars showed the highest progression rates. The major component of ALOSS was increased GR. Overall, only 10.1% of the observed ALOSS was contributed by increases in PD. Nearly two-thirds of the sites that experienced ALOSS had <3 mm of ALOSS at baseline. The weighted 5-year incidence estimate for ALOSS was 43.2% (N=145), and was higher among diabetics or those who had lost 1+ teeth since baseline. Smoking was not a significant predictor.

CONCLUSION

The rates and patterns of ALOSS among older South Australians are largely similar to those recently reported for North Carolinians. Most ALOSS in older people manifests as increases in GR, rather than PD. Diabetics should be targeted for intensive primary and secondary prevention of periodontal disease.

Progression of destructive periodontal diseases in three urban minority populations: role of clinical and demographic factors

BACKGROUND, AIMS

Differences in prevalence, severity and risk factors for destructive periodontal diseases have been reported for ethnic/racial groups. However, it is not certain whether this disparity is due to ethnicity/race or factors associated with ethnicity/race. Therefore, the present study addressed whether the rates of disease progression and clinical and demographic factors associated with disease progression varied among three ethnic/racial groups.

METHODS

The study population consisted of 53 Asian-, 69 African- and 62 Hispanic-Americans. Clinical measurements included probing depth, attachment level, gingival erythema, bleeding upon probing, suppuration and plaque. Disease progression was defined as a > 2 mm loss of attachment 2 months post baseline. The demographic variables examined included occupational status, report of a private dentist, years resident in the United States and smoking history.

RESULTS

The rate of attachment loss for the entire population was 0.04 mm or 0.24 mm/year. No significant differences were found among the three ethnic/racial groups. Variables associated with subsequent attachment loss for the entire population were age, male gender, mean whole-mouth plaque, erythema, bleeding upon probing, suppuration, attachment loss and probing depth, and belonging to the "unskilled" occupational group. No differences in risk profiles were found among the 3 ethnic/racial groups. Using stepwise logistic regression analysis, a model was developed to relate the clinical and demographic variables examined with subsequent attachment loss. The model indicated that prior attachment loss, gingival erythema, suppuration, being a current smoker and belonging to the "unskilled" occupational group conferred high risk of > 1 site of attachment loss of > 2 mm.

CONCLUSIONS

The results of this study suggest that variables associated with ethnicity/race, such as occupational status, are largely responsible for the observed disparity in destructive periodontal disease progression in these populations.

Perceived risk of deteriorating periodontal conditions

BACKGROUND

Interpretation of risk for periodontitis is critical for treatment planning. How periodontists assess risk for periodontitis is unclear.

PURPOSE

To study (1) what factors periodontists use when assessing the risks for worsening periodontal conditions anticipating that no treatment would be provided, and (2) if risk assessment is consistent and independent of specialty background training.

MATERIAL AND METHODS

Medical history, clinical dental data, full-mouth intra-oral radiographs, and slide pictures were obtained from each of 51 subjects, and the information was provided to 23 examiners.

RESULTS

The mean age of the study subjects was 51.5 years (SD +/- 17.7, range 23-81), with 28 women included. In 10 of the subjects, only gingivitis was identified, while 22 subjects had advanced chronic periodontitis. Risk scores assigned for 2 and 4 years differed significantly between European- and US-trained periodontists (p < 0.001) and between graduate students in training and periodontists from either the US or Europe (p < 0.01) (Wilcoxon n-pair test), with European periodontists scoring the lowest risks. Risk scores were correlated between groups (p < 0.01 with rho range 0.82-0.89) (Spearman's rank correlation). The best-fit model (r2 = 0.86) to assess perceived risk for worsening periodontal conditions based on data from all examiners combined included the following variables: (1) overall horizontal alveolar bone loss (p < 0.000), (2) age-adjusted proportional radiographic bone height score for the worst site (p < 0.000), and (3) proportion of pocket probing depths > or = 6.0 mm.

CONCLUSIONS

Differences exist on the scale of risk values based on specialty training. Consistency in scoring patterns exists. The examiners based their assigned risk scores almost exclusively on measures of existing disease severity, including radiographic bone loss and numbers of periodontal pockets > or = 6.0 mm, and excluding most known risk factors such as smoking, diabetes, and poor oral hygiene.

Factors influencing the effect of race on established periodontitis prevalence

OBJECTIVE

This paper identifies differences in prevalence of established periodontitis and evaluates factors that might explain the differences between non-Hispanic African Americans (n = 232) and whites (n = 199) in the Detroit tricounty area.

METHODS

Subjects from a disproportionate probability sample of community-dwelling adults were interviewed regarding demographic, psychosocial and enabling factors, dental health-related behaviors, and other risk factors, and had comprehensive in-home dental examinations.

RESULTS

The overall prevalence of established periodontitis was 20.8 percent; African Americans exhibited a significantly higher prevalence than whites (29.8% vs 17.7%). The crude association between race and prevalence of established periodontitis was significant (odds ratio [OR] for African Americans = 1.98; 95% confidence interval [CI] = 1.17,3.34). After controlling for other covariates, we found the effect of race may be modified by dental checkup visit frequency: African Americans with dental checkups at least once a year had almost a fourfold higher odds of established periodontitis (OR = 3.64; 95% CI = 1.43, 9.24) than their white counterparts with dental checkups at least once a year (the referent group); while African Americans with a dental checkups once every two years or less often were more than fourfold less likely to have established periodontitis (OR = 0.22; 95% CI = 0.08, 0.59) than their white counterparts in the referent group.

CONCLUSIONS

This analysis supports the disparity in periodontal health as part of the black:white health disparity when taking other factors into account. However, periodontal health disparities may be more complex than previously recognized, requiring greater understanding of factors related to dental care utilization in future studies evaluating this disparity.

Destructive periodontal diseases in minority populations

Disparities in the prevalence and severity of destructive periodontal diseases have been reported for American minority populations and have raised the following questions. Are differences in destructive periodontal disease prevalence and severity due to genetic or other confounding variables associated with ethnicity race? Do risk factors for destructive periodontal diseases differ among American minority populations or differ from the population at large? Answers to these questions will have profound impact on the direction of future research and the allocation of resources to address disparities in destructive periodontal diseases in American minority populations. Risk assessment studies that examined a set of clinical, demographic, immunologic, and microbiologic parameters of Asian Americans, African Americans, and Hispanic Americans resident in the greater New York City region suggest that occupational status, monitored as a surrogate variable for socioeconomic status, may be a more robust risk factor than ethnicity/race for destructive periodontal diseases in these populations.

Serum IgG antibody response to periodontal pathogens in minority populations: relationship to periodontal disease status and progression

Differences in periodontal disease prevalence, severity, subgingival microflora and host immune response have been reported for various ethnic/racial groups, which implies that risk factors for destructive periodontal disease progression may also vary in these populations. As it is possible that these differences may be due to confounding variables other than ethnicity/race, we have measured serum IgG antibody response to six periodontal pathogens, and compared these data with microbiological, clinical and demographic parameters in three urban minority populations. The study population consisted of 23 Asiatic, 48 African-American and 37 Hispanic subjects, who were resident in the greater New York region. Clinical indices that were recorded included pocket depth, attachment level, gingival erythema, bleeding upon probing, suppuration and supragingival plaque. Attachment level measurements were taken twice at each visit, and the difference between the means of pairs of measurements taken at baseline and two months later was used to determine disease progression. Subgingival microbiological species were identified and enumerated using DNA-DNA checkerboard hybridization. Serum IgG antibody levels to Actinobacillus actinomycetemcomitans serotyopes a and b, Bacteroides forsythus, Campylobacter rectus, Porphyromonas gingivalis and Prevotella intermedia were measured by enzyme-linked immunosorbant assay (ELISA). Mean serum IgG antibody to P. gingivalis was found to be higher in the African-American group, while IgG antibody to B. forsythus was lower in the Hispanic group. However, the African-American group also had greater mean probing depth, attachment loss, number of missing teeth and numbers of individuals within the unskilled occupational group. When the data were analyzed by occupational status, mean serum IgG antibody to P. gingivalis increased from professional to skilled to unskilled groups. For the entire study population, prior disease and subsequent attachment loss were associated with elevated serum IgG antibody to P. gingivalis. Increasing pocket depth, attachment level, gingival erythema and age were also positively correlated with serum IgG antibody to P. gingivalis, but not with serum IgG antibody to the other five subgingival species. No correlation was found between whole-mouth bacterial levels and homologous serum IgG antibody levels. These results suggest that elevated serum IgG antibody to P. gingivalis reflects destructive periodontal disease status, and may be considered a risk factor for disease progression in these ethnic/racial populations. In addition, although differences in serum IgG antibody profiles to subgingival species were found among the three ethnic/racial groups, environmental and socioeconomic variables may have a greater influence on serum IgG antibody levels in these populations.

Prevalence and risk indicators for destructive periodontal diseases in 3 urban American minority populations

BACKGROUND, AIMS

Destructive periodontal diseases have been reported disproportionately more prevalent and severe in African-Americans relative to other American populations. Differences in subgingival microbiota and host immune response have also been reported for African-Americans, implying that risk factors for disease progression may also differ for these populations. Since it is not clear whether these differences are truly genetic or due to confounding variables such as social economic status, we examined a series of clinical, environmental, demographic, and microbiologic features associated with periodontal disease status in a group of 185 urban minority subjects resident within the greater New York metropolitan area.

METHODS

The study population consisted of 56 Asian-American, 71 African-American and 58 Hispanic subjects. Clinical data recorded included pocket depth, attachment level, gingival erythema, bleeding upon probing, suppuration, and the presence of supragingival plaque. Environmental and demographic data recorded included smoking history, years resident in the United States, whether the subject reported a private dentist and occupational status. Subgingival plaque was sampled from the mesial aspect of all teeth exclusive of third molars and the levels of 40 subgingival species enumerated using checkerboard DNA-DNA hybridization.

RESULTS

The African-American group had more missing teeth, deeper periodontal pocket depth and more attachment loss than the Asian-American or Hispanic groups. However, the African-American group were less likely to report having a private dentist, had a greater proportion of smokers and a greater proportion of unskilled individuals. The profile of subgingival species differed among the three ethnic/racial groups with A. actinomycetemcomitans, N. mucosa, S. noxia and T. socranskii significantly elevated in the Asian-American group and P. micros significantly elevated in the African-American group. When subset by occupational status, numbers of missing teeth, pocket depth, attachment level and prior disease activity were all found increased in the unskilled relative to the professional group. Local factors including the mean % of sites with plaque, marginal gingival erythema, bleeding upon probing and suppuration were also elevated in the unskilled group. The microbial profile differed among the 3 occupational groups with the unskilled group having elevated numbers of species associated with destructive periodontal diseases.

CONCLUSIONS

Although greater destructive periodontal disease prevalence and severity were found in the African-American group, these results suggest that environmental and demographic variables, such as occupational status, may have a greater influence on risk indicators associated with disease prevalence and progression in these populations.

Complex sampling: implications for data analysis

Investigators in dental public health often use strategies other than simple random sampling to identify potential subjects; however, their statistical analyses do not always take into account the complex sampling mechanism. Often it is not clear whether a given strategy requires adjustment for stratification and/or cluster sampling of observations. We propose that the need for such adjustment depends on the primary study objective. As a general rule, we recommend that if the study goal is to estimate the magnitude of either a population value of interest (e.g., prevalence), or an established exposure-outcome association, adjustment of variances to reflect complex sampling is essential because obtaining appropriate variance estimates is a priority. However, if the study goal is to establish the presence of an association, especially in a preliminary investigation of novel conditions or understudied populations, obtaining appropriate variance estimates may not be of primary importance; hence, adjustment of variances for complex sampling is not always required, but often is recommended. This paper describes several types of complex sampling designs, methods of adjusting for complex sampling strategies, examples illustrating the effect of adjustment, and alternative approaches for analysis of complex samples.

The relevance of behavioural sciences in dental practice

The aim of this paper is to illustrate how knowledge from behavioural sciences is necessary and relevant in creating a successful dental practice, benefitting patients and dental professionals. There are many ways to create a successful dental practice, the products of which are the various treatments performed by dentists or dental hygienists for their patients. Advanced technologies and methods are constantly improving these treatments and thus the technical and managerial aspects of dentistry. However, the success of dental practice is not only dependent on the technique applied or the technical skills of dental professionals, but also on patients, their attitudes and behaviour and the interaction between dental professionals and patients. It is well known that the success of dental treatments (for example, periodontal, orthodontic or implants) depends on the patient's behaviour, which includes compliance with certain oral hygiene regimens or specific dental visiting patterns. The outcome of the treatment depends on both the dental professional's knowledge and skills and the patient's skills, objectives and expectations. Furthermore, dental professionals and patients should be satisfied with the treatment plan as well as the outcome. This paper argues that in order for this to happen dental professionals need additional knowledge and skills from fields outside traditional dental sciences. In order to treat patients successfully, dental professionals must understand and change or modify patient behaviour, and the knowledge necessary for this is provided by the behavioural sciences.

Periodontal conditions among the old elderly: five-year longitudinal study

In the past three decades, there has been a significant rise in the number of old elderly (85+ years old) in Finland, and more of these individuals are retaining their natural teeth. Numerous cross-sectional studies have reported on the periodontal health of the elderly (aged 75+), but very few long-term follow-ups have been reported. This study forms a part of the population-based Helsinki Aging Study (HAS) and compares the periodontal health status and the treatment needs at baseline with those of the same population five years later. The baseline study, in 1990-91, examined the dentate elderly born in 1904, 1909, and 1914, living in Helsinki, Finland (n = 196). The follow-up study was completed in 1995-96 (n = 73). Periodontal status was recorded by means of the Community Periodontal Index of Treatment Needs (CPITN) in 175 dentate subjects (55 males and 120 females) who met the criteria at baseline, and in 57 dentate elderly (17 males and 40 females), aged 81, 86, and 91 years, who remained at follow-up. Among the 57 dentate elderly who participated in both baseline and follow-up examinations, the mean number of teeth decreased from 15.9 to 15.1, and the mean number of remaining sextants from 4.2 to 3.7. There were minor changes in the periodontal health status during this five-year period, with an increase in code 2 (from 43% to 58%) and a decrease in code 3 (from 38% to 25%). Nevertheless, the overall treatment needs remained unchanged. It can be concluded that the periodontal health of the elderly had remained stable for 5 years, and almost no change was observed in their treatment needs. Therefore, periodontal disease in the elderly who are relatively healthy is not caused by the aging process.

Oral Chlamydia trachomatis in patients with established periodontitis

Periodontitis is considered a consequence of a pathogenic microbial infection at the periodontal site and host susceptibility factors. Periodontal research supports the association of Actinobacillus actinomycetemcomitans, Porphyromonas gingivalis, Prevotella intermedia, and Bacteroides forsythus, and periodontitis; however, causality has not been demonstrated. In pursuit of the etiology of periodontitis, we hypothesized that the intracellular bacteria Chlamydia trachomatis may play a role. As a first step, a cross-sectional study of dental school clinic patients with established periodontitis were assessed for the presence of C. trachomatis in the oral cavity, and in particular from the lining epithelium of periodontal sites. C. trachomatis was detected using a direct fluorescent monoclonal antibody (DFA) in oral specimens from 7% (6/87) of the patients. Four patients tested positive in specimens from the lining epithelium of diseased periodontal sites, one patient tested positive in healthy periodontal sites, and one patient tested positive in the general mucosal specimen. In conclusion, this study provides preliminary evidence of C. trachomatis in the periodontal sites. Planned studies include the use of a more precise periodontal epithelial cell collection device, the newer nucleic acid amplification techniques to detect C. trachomatis, and additional populations to determine the association of C. trachomatis and periodontitis.

A 5-year study of attachment loss and tooth loss in community-dwelling older adults

Tooth loss is a widely recognized endpoint measure for the effects of periodontal diseases and the impact of periodontal therapy. In fact, traditional clinical measures of periodontal status often are considered to be surrogate endpoints in that they are assumed to be related to tooth loss. However, the strength of the relationship between attachment loss and tooth loss in a representative population of untreated subjects has not been studied extensively. The purpose of this paper is to present the trends in attachment loss over a 5-yr period in a population of community-dwelling elderly blacks and whites. Specifically, this paper presents attachment loss trends both at the person and tooth level to address the following issues; 1) whether teeth that experience attachment loss during 1 time period are more likely to be lost at the next time period; and 2) given similar levels of attachment loss, why are some people more likely to lose teeth? In 1988, the University of North Carolina School of Dentistry initiated the Piedmont 65+ Dental Study, which was designed to elicit 800 dentate respondents in the 5-country area who were examined again at 18, 36 and 60 months. Our findings indicated that teeth with poorer attachment level at baseline had a higher probability of being lost during the next 5 yr and teeth that experienced attachment loss during a time period were more likely to be lost during the next time period than teeth without additional attachment loss. In addition, it appears that there are person-level characteristics associated with increasing tendency towards tooth loss in people with similar periodontal status, a finding that may clarify the relationship between attachment loss and tooth loss.