Profiles of destructive periodontal disease in different populations

Current concepts and an alternative perspective on periodontal disease

BACKGROUND

Epidemiological data from countries worldwide show a consistent pattern implying that a fraction of around 10% of those over 40-50 years in all populations will exhibit severe periodontitis with the potential risk of losing teeth during their life-time. The subgingival microbiota shows striking similarities between populations irrespective of disease severity and can only marginally explain the clinical pattern. It is also difficult to explain this pattern by genetic and acquired risk factors such as systemic disease (e.g. diabetes) or habits (e.g. smoking) even if they may have a confounding effect on the disease.

MAIN TEXT

Inflammation of the gingiva appears to be a normal and physiological response to the presence of commensal bacteria along the gingival crevice and in the dental biofilm. Over many years of exposure to the dental biofilm, the chronic inflammation in the gingiva gradually results in a loss of attachment and bone loss. Numerous laboratory and clinical studies have provided insight into the potential role of determinants that are associated with periodontitis. However, it has been difficult to relate the findings to the pattern of the distribution of the disease observed in epidemiological studies. We propose a simple and parsimonious model that considers all the multitude of potential determinants as creating effectively random noise within the dental biofilm to which the tissues react by accumulating the effects of this noise.

CONCLUSIONS

We suggest that such a model can explain many of the epidemiological features of periodontal breakdown over time, and we discuss its clinical implications.

Caries and Periodontitis: Contesting the Conventional Wisdom on Their Aetiology

We review the literature on the oral microbiome and the role of the microbiota in the development of dental caries and periodontitis. While most research has been focused on identifying one or more specific determinants of these diseases, the results have provided limited predictive value and have not been able to explain the variation in the distribution of these diseases observed in epidemiological or clinical studies. Drawing on existing knowledge about the nature of the oral microbiota, we suggest that a stochastic model based on the Weiner process provides simple and parsimonious explanations for the pathogenesis of both caries and periodontitis, making few assumptions, and providing explanations for phenomena that have hitherto proved difficult, or have required complex arguments, to explain. These diseases occur as the result of the dental hard tissues and periodontal tissues integrating the random "noise" caused by normal metabolic activities of commensal microorganisms in the dental biofilm. The processes that result in the progression and regression of caries and periodontitis may be considered as "natural," rather than pathological, even if, when left unchecked over long periods of time, they can result in the development of pathologies. The likelihood of progression or regression can be influenced by other determinants, but these processes will nevertheless occur in the absence of such influences. The distributional characteristics of the model approximate the findings of epidemiological studies indicating that, for both caries and periodontitis, there will be few sites affected in the early period after the eruption of the permanent dentition, but in those older there is an almost linear relationship with increasing age; furthermore, the longer a site survives without being affected, the less likely that it will be affected. We discuss the clinical and public health importance of these findings.

Prevalence of Periodontal Destruction and Putative Periodontal Pathogens in the Same Lebanese Family

AIM

Periodontal diseases are associated with microorganisms rich in Gram-negative species. Several studies have indicated the presence of few a periodontopathic microorganisms in the same family. A parent with severe adult periodontitis, who is infected with bacteria associated with periodontal disease, may function as a source of infection. Their children may be at a greater risk to become colonized with bacteria. The purpose of this investigation was (1) to explore the presence of three bacteria, such as Porphyromonas gingivalis (PG), Prevotella intermedia (PI), and Aggregatibacter actinomycetemcomitans (AA) in the same Lebanese family and (2) to study the clinical destruction in the same family and their relations as members of this family due to the presence of PG.

MATERIALS AND METHODS

A total of 10 families were screened; only 5 (13 females and 5 males) were selected for this study, and at least one member of the family had untreated periodontal disease, chronic or aggressive. Every participant signed an informed consent form. A total of 18 available deoxyribonucleic acid (DNA) samples were taken to analyze the presence of three periodontal bacteria.

STATISTICS

Multiple logistic regression was used for the exact methods.

RESULTS

All 18 patients showed a positive result for PI. Also, PG. was recognized in 15 patients while AA was not detected in any of the subjects. All couples suffered from periodontitis, chronic or aggressive forms, five children suffered from gingivitis, three children had no clinical manifestation, and only one suffered from localized aggressive periodontitis. The statistical analysis showed with each 1 year of increase in age, the odds of having periodontal disease multiply by 1.39, i.e., age as a risk factor for periodontal disease due to the presence of PG and sharing the same plate.

CONCLUSION

This investigation demonstrates a high prevalence of periodontal microorganisms in children and young adults of Lebanese periodontitis parents and a microbiological similarity between the children and their mothers. All these factors could be a high risk of developing periodontal disease in the future.

CLINICAL SIGNIFICANCE

This article shows that vertical transmission of microorganisms is a possible risk factor for developing periodontal disease in the offspring.

Periodontal disease in a remote Asian population: association between clinical and microbiological parameters

OBJECTIVE

The aim was to clinically and microbiologically describe the periodontal conditions in a remote adult Asian population with poor oral hygiene.

METHODS

The subjects were 30-60-year-old adults of Karen Hill tribes with no access to dental care. Eighty-six subjects were selected randomly. Clinical registrations included number of remaining teeth, plaque index (PlI), bleeding on probing (BoP), clinical attachment loss (CAL), and probing pocket depth (PPD). Subgingival plaque samples were collected and analyzed with the checkerboard method.

RESULTS

Subjects of the study group had mean number of remaining teeth of 26.5 despite the abundant plaque and a high bleeding score. Severe periodontitis (CAL ≥ 7 mm) was recorded in 12.9% of the youngest age group (30-39 years) while it was significantly higher (52%) in the middle group (40-49 years) and (60%) in the eldest age group (50-60 years). Pathological pocketing (PPD ≥ 7 mm) was significantly lower in all age groups. Age, betel chewing, and a microbiological cluster including at least one of Prevotella tannerae, Filifactor alocis and Porphyromonas endodontalis significantly correlated with the severity of periodontal disease.

CONCLUSION

Age, betel chewing, and a new bacterial complex other than the "red complex" correlated to periodontal breakdown in this remote adult Asian population.

Determinants of periodontal health in pregnant women and association with infants' anthropometric status: a prospective cohort study from Eastern Uganda

Background

Preterm-low birth weight delivery is a major cause of infant morbidity and mortality in sub Saharan Africa and has been linked to poor periodontal health during pregnancy. This study investigated predisposing and enabling factors as determinants of oral health indicators in pregnancy as well as the association between periodontal problems at 7 months gestational age and the infants’ anthropometric status.

Method

A community –based prospective cohort study was conducted in Mbale, Eastern Uganda between 2006 and 2008. Upon recruitment, 713 pregnant women completed interviews and a full mouth oral clinical examination using the CPITN (Community Periodontal Index of Treatment Need) and OHI-S (Simplified Oral Hygiene) indices. A total of 593 women were followed up with anthropometric assessments of their infants 3 weeks after delivery. Multiple logistic regression analyses were used to identify independent determinants of periodontal problems and use of dental services during pregnancy. Analysis of covariance (ANCOVA) was used to investigate the relationship between periodontal problems and the child’s anthropometric status in terms of wasting, underweight and stunting.

Results

A total of 67.0% women presented with periodontal problems, 12.1% with poor oral hygiene, 29.8% with recent dental visit and 65.0% with periodontal symptoms. Of the infants, 2.0% were wasted, 6.9% were underweight and 10.0% were stunted. The odds ratio of having CPI > 0 increased with increased maternal age and single marital status, and was lower in primiparous women and those who used mosquito bed nets. Mean wasting scores discriminated between mothers with CPI = 0 and CPI > 0 as well as between mothers with good and poor OHI-S scores.

Conclusions

Socio-demographic factors and information about oral health were associated with oral health indicators in pregnant women. Second, the height- for- age status at 3 weeks postpartum was worse in infants of mothers having periodontal problems and poor oral hygiene during pregnancy. Efforts to prevent oral diseases during pregnancy should be part of the local state and national health policy agenda in Uganda.

Dental caries in Rome, 50-100 AD

Scarce information exists on the clinical features of dental caries in the Imperial Roman population and no structural data on caries lesions from this period have so far been published. We report on the findings of 86 teeth (50-100 AD) found during archaeological excavations of the temple of Castor and Pollux in the Forum Romanum. We found that nearly all teeth had large carious cavities extending into the pulp. The distribution and size of the caries lesions were similar to those found in contemporary adult populations in Africa and China living without access to dental care. Most lesions had a hypermineralized zone in the dentin at the advancing front of the carious cavities as revealed by micro-computed tomography. This biological dentin reaction combined with the morphology of the cavities might indicate that some temporary topical pain relief and intervention treatment slowed down the rate of lesion progression. This is indirectly supported by examination of cavities of similar size and depth from a contemporary population without access to dental health care. In contrast to the lesions in the Roman teeth, these lesions did not exhibit a hypermineralized dentin reaction. We investigated whether the Pb isotopic composition of enamel and/or dentin of a single tooth matched that of a sample of an ancient Forum water lead pipe. The Pb isotopic composition of the tooth did not match that of the tube, suggesting that the subjects were exposed to different Pb sources during their lifetime other than the lead tubes.

Multilevel analysis of clinical parameters in chronic periodontitis after root planing/scaling, surgery, and systemic and local antibiotics: 2-year results

AIM

Find the periodontal treatment that best maintained clinical results over time evaluated by changes in pocket depth (PD) and clinical attachment level (CAL).

METHODS

229 patients with chronic periodontitis from USA (n=134) and Sweden (n=95) were randomly assigned to eight groups receiving (1) scaling+root planing (SRP) alone or combined with (2) surgery (SURG)+systemic amoxicillin (AMOX)+systemic metronidazole (MET); (3) SURG+local tetracycline (TET); (4) SURG; (5) AMOX+MET+TET; (6) AMOX+MET; (7) TET; and (8) SURG+AMOX+MET+TET. Antibiotics were given immediately after SRP. Plaque, gingival redness, bleeding on probing, suppuration, PD, and CAL were recorded at baseline and after 3, 6, 12, 18, and 24 months. Treatment effects were evaluated by linear multilevel regression and logistic multilevel regression models. We considered only data from sites with a baseline PD of at least 5 mm of 187 patients completing the study.

RESULTS

Surgically treated patients experienced most CAL loss. Adjunctive therapy including SURG was most effective in reducing PD. Combining SURG with AMOX, MET, and TET gave significant clinical benefits. Past and current smoking habits were significant predictors of deeper PD. Only current smoking was a significant predictor of CAL loss. Bleeding, accumulation of plaque, gingival redness, and suppuration were significant predictors of further CAL loss and deeper PD.

CONCLUSIONS

Both surgical and non-surgical therapies can be used to arrest chronic periodontitis. SURG+AMOX+MET+TET gave best maintenance of clinical results.

Global Oral Health Inequalities

Periodontal diseases constitute one of the major global oral health burdens, and periodontitis remains a major cause of tooth loss in adults worldwide. The World Health Organization recently reported that severe periodontitis exists in 5-20% of adult populations, and most children and adolescents exhibit signs of gingivitis. Likely reasons to account for these prevalent diseases include genetic, epigenetic, and environmental risk factors, as well as individual and socio-economic determinants. Currently, there are fundamental gaps in knowledge of such fundamental issues as the mechanisms of initiation and progression of periodontal diseases, which are undefined; inability to identify high-risk forms of gingivitis that progress to periodontitis; lack of evidence on how to prevent the diseases effectively; inability to detect disease activity and predict treatment efficacy; and limited information on the effects of integration of periodontal health as a part of the health care program designed to promote general health and prevent chronic diseases. In the present report, 12 basic, translational, and applied research areas have been proposed to address the issue of global periodontal health inequality. We believe that the oral health burden caused by periodontal diseases could be relieved significantly in the near future through an effective global collaboration.

Salivary infectious agents and periodontal disease status

BACKGROUND AND OBJECTIVES

The potential of salivary microorganisms to diagnose periodontal disease and to guide periodontal treatment is a research topic of current interest. This study aimed to determine whether the salivary counts of periodontopathic microbes correlated with the periodontal pocket counts of the same infectious agents, and whether the salivary counts of the test infectious agents could distinguish among individuals with periodontal health and various types of periodontal disease.

MATERIAL AND METHODS

The study included 150 systemically healthy adults, of whom 37 were periodontally healthy, 31 had gingivitis, 46 had chronic periodontitis and 36 had aggressive periodontitis. Each study subject contributed microbial samples from the two deepest periodontal pockets of the dentition and from whole saliva. Aggregatibacter actinomycetemcomitans, Campylobacter rectus, Fusobacterium nucleatum, Porphyromonas gingivalis, Prevotella intermedia, Tannerella forsythia and Epstein-Barr virus were identified using the TaqMan real-time PCR methodology. Statistical analysis was performed using the Mann-Whitney U-test and the receiver operating characteristic statistics.

RESULTS

C. rectus, F. nucleatum, P. gingivalis, P. intermedia and T. forsythia occurred with significantly higher copy-counts in salivary samples from patients with gingivitis, chronic periodontitis and aggressive periodontitis than from periodontally healthy individuals. A. actinomycetemcomitans only showed higher salivary copy-counts in subjects with aggressive periodontitis compared with subjects with healthy periodontium, and the salivary copy-counts of Epstein-Barr virus did not reveal any significant difference among the four subject groups studied. The diagnostic sensitivity for periodontitis was 89.19 for P. gingivalis and for T. forsythia and 86.49 for P. intermedia, with specificities ranging from 83.78 to 94.59. The optimal copy-counts per mL saliva for identifying periodontitis were 40,000 for P. gingivalis, 700,000 for T. forsythia and 910,000 for P. intermedia.

CONCLUSION

Salivary copy-counts of P. gingivalis, T. forsythia and P. intermedia appear to have the potential to identify the presence of periodontitis, whereas the salivary level of the other test infectious agents may possess little or no diagnostic utility. Longitudinal studies are warranted to determine the ability of salivary copy-counts of major periodontopathic bacteria to predict future periodontal breakdown.

Socio-demographic factors related to periodontal status and tooth loss of pregnant women in Mbale district, Uganda

Background

Information on the socio-behavioral distribution of periodontal status and tooth loss in pregnancy emanating from sub Saharan Africa is sparse. This study examined periodontal status and tooth loss in pregnant Ugandan women and assessed the relationship with socio-demographics factors, parity, dental care and oral hygiene.

Methods

Mothers were participants of a multicentre cluster-randomized behavioral intervention study (PROMISE-EBF Safety and Efficacy of Exclusive Breast feeding Promotion in the Era of HIV in Sub-Saharan Africa). In Uganda, these were pregnant women resident in Mbale district, recruited into the PROMISE EBF study between January 2006 and June 2008. A total of 886 women were eligible to participate of whom information became available for 877 (participation rate 98.9%, mean age 25.6) women who participated in the recruitment interview and 713 (mean age 25.5) women who got a clinical oral examination. Periodontal status was assessed using the Community Periodontal Index of Treatment Needs (CPITN).

Results

The prevalence of tooth loss was 35.7%, 0.6% presented with pockets shallow pockets (4–5 mm), whereas 3.3% and 63.4% displayed bleeding and calculus, respectively. A total of 32.7% were without any sign of periodontal disease. Binary logistic regression analyses revealed that older women, women from larger households and those presenting with microbial plaque were respectively, 3.4, 1.4 and 2.5 times more likely to have CPI score >0. Rural (OR = 0.9), nulliparous (OR = 0.4) and women who never visited a dentist (OR = 0.04) were less likely, whereas women from larger households (OR = 1.5) were more likely to have lost at least one tooth.

Conclusion

The results revealed moderate prevalence of bleeding and tooth loss, high prevalence of calculus, low frequency of pockets 4–5 mm. Disparity in pregnant women's oral health related to parity suggests that education of maternity care providers concerning oral health in pregnancy is warranted.

Trial registration

ClinicalTrials.gov Identifier NCT00397150

Prevalence and distribution of principal periodontal pathogens worldwide

BACKGROUND

Detailed genetic analysis of bacteria has demonstrated an unanticipated genetic diversity within species, which often reveals evolutionary lineages that are disproportionately associated with infection. There is evidence that some evolutionary lineages of bacteria have adapted to particular ethnic groups.

AIM

This review analyzes to what extent observed differences in periodontal disease prevalence among ethnically or geographically distinct populations may be explained by restricted host adaptation of clones of principal periodontal pathogens.

RESULTS

Carriage rates of several putative periodontal pathogens and particular subsets of these species vary between ethnic groups. Few of these differences can, with the limited information available, be directly related to differences in periodontal disease prevalence. Asian populations are regularly colonized with Actinobacillus actinomycetemcomitans serotype c with questionable pathogenic potential. Conversely, the JP2 clone of A. actinomycetemcomitans has enhanced virulence and causes significantly higher prevalence of aggressive periodontitis in adolescents whose descent can be traced back to the Mediterranean and Western parts of Africa. Some genetically distinct types of Porphyromonas gingivalis are more associated with disease than others, but additional work is required to relate this to clinical differences.

CONCLUSIONS

Studies that take into account differences linked to the genetics of both patients and potential pathogens are likely to give better insight into the aetiology of periodontal diseases.

Periodontal attachment loss in an untreated isolated population of Brazil

BACKGROUND

The aim of this study was to assess the prevalence, extent, and severity of clinical attachment loss (CAL) and to investigate the association of demographic, socioeconomic, and behavioral risk indicators with CAL in an untreated isolated population in Brazil.

METHODS

All subjects aged > or =12 years were identified by a census. Participants were submitted to a full-mouth clinical examination of six sites per tooth and were interviewed using a structured, written questionnaire.

RESULTS

Among the 214 subjects who were interviewed and examined clinically, CAL > or =5 mm in at least one site was observed in 8% of the 12- to 19-year-olds and in all dentate subjects > or =50 years of age; the age-dependent prevalence of CAL > or =7 mm in at least one site ranged from 5% among 12- to 19-year-olds to 83% among subjects > or =50 years old. Multivariate analysis identified plaque (odds ratio [OR] = 2.8), supragingival calculus (OR = 2.9 to 10.6), age > or =30 years (OR = 11.4), and smoking (OR = 2.4) as risk indicators for CAL > or =5 mm and smoking (OR = 8.2) as a risk indicator for CAL > or =7 mm.

CONCLUSIONS

CAL is highly prevalent in this isolated population. The high occurrence of CAL in young age groups and the confirmation of traditional risk indicators for CAL in this study suggest that other factors, such as host susceptibility, may be needed to explain the high levels of CAL found. Age and behavioral factors were risk indicators associated significantly with the CAL found in this population and may be useful indicators of high-risk subjects for periodontal diseases.

Refining exposure definitions for studies of periodontal disease and systemic disease associations

BACKGROUND

Substantial variation exists in reported associations between periodontal infections and cardiovascular disease. Imprecise periodontal exposure definitions are possible contributors to this variability. We studied appropriate exposure definitions for studying associations between clinical periodontal disease (PD) and systemic disease.

METHODS

Data originate from men and women aged 20-79 enrolled in the Study of Health in Pomerania (SHIP) from 1997-2001. Age and sex-adjusted correlation analysis identified PD definitions with the highest cross-sectional associations with three subclinical markers of systemic disease: plasma fibrinogen (n = 3481), serum hemoglobin A1c (HbA1c) (n = 3480), and common carotid artery intima-media thickness (c-IMT) (n = 1745, age > or = 45).

RESULTS

In men and women, percent of sites with attachment loss (AL) > or =6 mm and tooth loss both revealed the highest correlation with HbA1c (rho = 0.11; several other definitions related similarly), while the strongest fibrinogen correlation was observed with percent of sites with pocket depth > or =3 mm (rho = 0.19). Findings for c-IMT among men were strongest for percent of sites with AL > or =6 mm (rho = 0.14; several other definitions related similarly) while among women, percent of sites with pocket depth > or =5 or 6 mm had the highest observed correlation (rho = 0.13).

CONCLUSIONS

A range of near optimal definitions varied according to gender and whether the systemic disease marker reflected an acute or chronic situation. Pocket depth was more strongly correlated with the acute marker fibrinogen while attachment and tooth loss tended to be more strongly correlated with the chronic markers, HbA1c, and c-IMT. These findings can be useful in designing future studies investigating the association between PD and systemic disease.

Epidemiology of periodontal status in dentate adults in France, 2002-2003

BACKGROUND AND OBJECTIVE

Few recent nationwide studies of the periodontal landscape in European countries have been developed from the point of view of attachment loss and pocket depth. Decision makers are not always in a position to estimate the burden of periodontal disease. The purpose of this study was to investigate the prevalence and the oral distribution of periodontal status among dentate adults in the general population of France.

MATERIAL AND METHODS

In 2002-2003, a National Periodontal and Systemic Examination Survey was organized to a stratified quota sample of 2144 adults, aged 35-64 years, nationwide. Participants with six or more teeth were selected from the Health Examination Centers of the National Health Insurance. Measurement of periodontal health was assessed by clinical attachment level and probing depth.

RESULTS

A total of 95.40% and 82.23% of adults were found to have clinical attachment loss and periodontal pockets, respectively. Population prevalence estimates indicated that loss of attachment > or = 5 mm is 46.68% and probing depth (> 5 mm) is 10.21%. However, clinical attachment loss of > or = 5 mm occurred in only 0.88 sites in an individual. Periodontal depth pocket generalized forms were as follows: 78% slight, 18% moderate and 4% severe. Multiple logistic regression analyses showed significant differences of attachment loss values between types of tooth (molar, incisors, canines, or premolars).

CONCLUSION

Based on the International Classification of Periodontal Diseases, approximately 50% of adults in France may suffer from a severe attachment loss problem. Periodontal pockets are an uncommon condition in France. Significant differences in the prevalence of loss of attachment and probing depth with respect to location of attack have implications in the purchase and development of screening and treatment services.

Maternal oral health status and preterm low birth weight at Muhimbili National Hospital, Tanzania: a case-control study

Background

The study examined the relationship between oral health status (periodontal disease and carious pulpal exposure (CPE)) and preterm low-birth-weight (PTLBW) infant deliveries among Tanzanian-African mothers at Muhimbili National Hospital (MNH), Tanzania.

Methods

A retrospective case-control study was conducted, involving 373 postpartum mothers aged 14–44 years (PTLBW – 150 cases) and at term normal-birth-weight (TNBW) – 223 controls), using structured questionnaire and full-mouth examination for periodontal and dentition status.

Results

The mean number of sites with gingival bleeding was higher in PTLBW than in TNBW (P = 0.026). No significant differences were observed for sites with plaque, calculus, teeth with decay, missing, filling (DMFT) between PTLBW and TNBW. Controlling for known risk factors in all post-partum (n = 373), and primiparaous (n = 206) mothers, no significant differences were found regarding periodontal disease diagnosis threshold (PDT) (four sites or more that had probing periodontal pocket depth 4+mm and gingival bleeding ≥ 30% sites), and CPE between cases and controls. Significant risk factors for PTLBW among primi- and multiparous mothers together were age ≤ 19 years (adjusted Odds Ratio (^aOR) = 2.09, 95% Confidence interval (95% CI): 1.18 – 3.67, P = 0.011), hypertension (^aOR = 2.44, (95% CI): 1.20 – 4.93, P = 0.013) and being un-married (^aOR = 1.59, (95% CI): 1.00 – 2.53, P = 0.049). For primiparous mothers significant risk factors for PTLBW were age ≤ 19 years (^aOR = 2.07, 95% CI: 1.13 – 3.81, P = 0.019), and being un-married (^aOR = 2.58, 95% CI: 1.42 – 4.67, P = 0.002).

Conclusions

These clinical findings show no evidence for periodontal disease or carious pulpal exposure being significant risk factors in PTLBW infant delivery among Tanzanian-Africans mothers at MNH, except for young age, hypertension, and being unmarried. Further research incorporating periodontal pathogens is recommended.

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.

Viruses in periodontal disease - a review

The purpose of this review was to evaluate the evidence supporting the hypothesis that viral infection plays a role in the development of periodontitis. An involvement in periodontal diseases has been suspected specifically for human immunodeficiency virus (HIV) and herpes viruses. An association has been demonstrated between HIV infection and some distinct forms of periodontal infection, i.e. necrotizing lesions. Furthermore, reports of increased prevalence and severity of chronic periodontitis in HIV-positive subjects suggests that HIV infection predispose to chronic periodontitis. Several studies, most of them from the same research group, have demonstrated an association of herpesviruses with periodontal disease. Viral DNA have been detected in gingival tissue, gingival cervicular fluid (GCF) and subgingival plaque from periodontaly diseased sites. In addition markers of herpesviral activation have been demonstrated in the GCF from periodontal lesions. Active human cytomegalovirus (HCMV) replication in periodontal sites may suggest that HCMV re-activation triggers periodontal disease activity. Concerns regarding sampling, methods and interpretation cast doubts on the role of viruses as causes of periodontal disease.

Periodontal status and preterm low birth weight: a case control study

BACKGROUND

Previous studies have suggested that periodontal disease may be an important risk factor for preterm low birth weight. However, the link between periodontal health status of pregnant women and preterm low birth weight is contentious, as recent studies found no association between periodontitis and pregnancy outcome.

OBJECTIVE

The aim of this study was to investigate this potential link in a German Caucasian population.

METHODS

Fifty-nine pregnant women with a high risk for a preterm low birth weight infant (suffering from preterm contractions, cases, group 1) as well as 42 control women with no preterm contractions during pregnancy and having an infant appropriate for date and weight (>or= 37 weeks gestation, >or= 2500 g, group 2) were examined. Clinical periodontal status was recorded on a full mouth basis. Subgingival plaque samples were taken and periodontal pathogens were identified by polymerase chain reaction. Additionally, interleukin-1 beta level in gingival crevicular fluid was analysed.

RESULTS

The mean percentage of sites showing moderate to advanced attachment loss (>or=3 mm) was low in all study groups (group 1: 9.9 +/- 11.2%; group 2:10.6 +/- 14.1%, respectively). No significant differences between the groups in any aspects of the studied periodontitis parameters could be detected. Using a logistic regression model controlling for known preterm low birth weight risk factors, no periodontitis-associated factors increased risk for preterm contractions or preterm low birth weight. The odds ratio (OR) was 1.19 for preterm contractions, the 95% confidence interval (CI) 0.46; 3.11 and 0.73 for preterm low birth weight; 95% CI: 0.13; 4.19, respectively.

CONCLUSION

In this population, periodontitis was not a detectable risk factor for preterm low birth weight in pregnant women.

Risk determinants of periodontal disease - an analysis of the Study of Health in Pomerania (SHIP 0)

BACKGROUND

In this study, risk determinants were determined for periodontal disease in the representative population sample (n=3146) of the Study of Health in Pomerania.

METHODS

After examining the net random sample (response 69%) and exclusion of edentulous cases and those with missing values, 2595 subjects remained. Using a multivariate, fully adjusted logistic regression, different definitions of "periodontally diseased/healthy" were examined as the dependent variable (extent of attachment loss (AL> or =4 mm, combined AL and tooth loss). The independent variables used were sociodemographic factors (age, gender, income, education), medical factors (systemic diseases, drugs), behavioral factors (regular dental checkup, smoking), and oral factors (presence of supragingival calculus and plaque).

RESULTS

The following risk determinants were found for AL: male gender, presence of supragingival plaque and calculus, smoking, low educational level. For the combination of AL and tooth loss, risk determinants were female gender, supragingival plaque, smoking, and low educational level. Consumption of antiallergic medications and regular dental checkups proved to be protective. Smoking was the most influential risk determinant. These parameters explained approximately 43-55% of the variation.

CONCLUSION

These results concur with those of the literature. In order to explain disease status further, host-response and microbiological factors must also be examined.

Genes and gene polymorphisms associated with periodontal disease

The scientific literature during the last ten years has seen an exponential increase in the number of reports claiming links for genetic polymorphisms with a variety of medical diseases, particularly chronic immune and inflammatory conditions. Recently, periodontal research has contributed to this growth area. This new research has coincided with an increased understanding of the genome which, in turn, has permitted the functional interrelationships of gene products with each other and with environmental agents to be understood. As a result of this knowledge explosion, it is evident that there is a genetic basis for most diseases, including periodontitis. This realization has fostered the idea that if we can understand the genetic basis of diseases, genetic tests to assess disease risk and to develop etiology-based treatments will soon be reality. Consequently, there has been great interest in identifying allelic variants of genes that can be used to assess disease risk for periodontal diseases. Reports of genetic polymorphisms associated with periodontal disease are increasing, but the limitations of such studies are not widely appreciated. While there have been dramatic successes in the identification of mutations responsible for rare genetic conditions, few genetic polymorphisms reported for complex genetic diseases have been demonstrated to be clinically valid, and fewer have been shown to have clinical utility. Although geneticists warn clinicians on the over-enthusiastic use and interpretation of their studies, there continues to be a disparity between the geneticists and the clinicians in the emphasis placed on genes and genetic polymorphism associations. This review critically reviews genetic associations claimed for periodontal disease. It reveals that, despite major advances in the awareness of genetic risk factors for periodontal disease (with the exception of periodontitis associated with certain monogenetic conditions), we are still some way from determining the genetic basis of both aggressive and chronic periodontitis. We have, however, gained considerable insight into the hereditary pattern for aggressive periodontitis. Related to our understanding that it is autosomal-dominant with reduced penetrance comes a major clinically relevant insight into the risk assessment and screening for this disease, in that we appreciate that parents, offspring, and siblings of patients affected with aggressive periodontitis have a 50% risk of this disease also. Nevertheless, we must exercise caution and proper scientific method in the pursuit of clinically valid and useful genetic diagnostic tests for chronic and aggressive periodontitis. We must plan our research using plausible biological arguments and carefully avoid the numerous bias and misinterpretation pitfalls inherent in researching genetic associations with 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.

Reliability of clinical attachment level recordings: effects on prevalence, extent, and severity estimates

BACKGROUND

Although unreliability of periodontal measurements is considered mainly to concern attempts to detect true changes in longitudinal studies, it is also a source of variability that may substantially decrease the precision of estimates obtained in cross-sectional studies. This study assessed the effects of measurement errors on estimates of prevalence, extent, and severity of clinical attachment loss.

METHODS

Four examiners performed repeat attachment level recordings in 128, 122, 134, and 133 adolescents, respectively, who participated in a study of clinical attachment loss among 9,162 high school students from Santiago, Chile. A total of 48,954 duplicate recordings were made. Two examiner teams carried out repeat examinations among 292 and 254 subjects, respectively, corresponding to a total number of 51,600 duplicate recordings for interexaminer reliability assessment.

RESULTS

A sizeable imprecision was noted regarding prevalence estimates, particularly at the > or = 1 mm level, whereas examiners were reasonably consistent in the assessment of the number of sites with clinical attachment loss. Ninety-five percent of the differences regarding the number of sites with clinical attachment loss > or = 1 mm were in the range from -5 to 5 sites for intraexaminer comparisons, and from -9 to 8 sites for interexaminer comparisons. These differences should be seen in light of the number of sites affected, which ranged from 0 to 85 sites.

CONCLUSIONS

Examiner variation may preclude comparisons of prevalence estimates between studies. Valid comparisons may be made between studies of extent estimates provided that uniform parameters are used to express the extent of periodontal breakdown.

Periodontal conditions among adults in Southern Thailand

OBJECTIVE

To describe the periodontal conditions among 30-39- and 50-59-year-old rural Thais from the Province of Songkhla, Southern Thailand.

METHODS

A total of 359 dentate persons were given a clinical examination comprising recordings of plaque and calculus in six teeth, and bleeding on probing, attachment level and pocket depth in six sites of all teeth present, except third molars. The same examiner carried out all examinations. Information on religious faith, smoking habits and use of betel was obtained by interview. A subset consisting of 60 persons was reexamined for attachment level 6 months later by another examiner.

RESULTS

The oral hygiene conditions were poor with abundant amounts of both plaque and calculus. Gingival bleeding was essentially ubiquitous. The prevalence of attachment loss > or = 4 mm was 92% among 30-39-year-olds and 100% among 50-59-year-olds. The average percentage of sites affected in the two age groups was 23.9% and 63.9%. Pockets > or = 4 mm were seen in 84% of the 30-39-year-olds and in 93% of the 50-59-year-olds. Older age, Thai Buddhist faith and a high percentage of sites with calculus were significant positive predictors of a high percentage of sites with attachment loss > or = 4 mm, whereas older age and Thai Buddhist faith were the only statistically significant predictors of a high percentage of sites with attachment loss > or = 7 mm.

CONCLUSION

The results indicate that this Thai population may have more widespread and severe periodontal destruction than other Asian populations, but failed to confirm the contention that Muslim faith is associated with more severe periodontal destruction.

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.

Comparison of periodontal disease status of adults in two untreated indigenous populations of Guatemala, Central America

OBJECTIVE

To compare the periodontal disease levels of two distinct indigenous populations of Guatemala, Central America, to determine whether differences exist.

MATERIAL AND METHODS

Cross-sectional studies were performed in adults from the communities of San Juan La Laguna, SJLL (n = 125) and Tzununa (n = 54). In both cases, full-mouth pocket probing depths (PPDs) and clinical attachment levels (CALs) were measured by a single examiner, and the same examiner was employed in both studies. Recession at each site was derived from PPD and CAL measures.

RESULTS

Tooth number did not differ significantly between SJLL and Tzununa (28.0 and 27.2, respectively). With respect to periodontal disease status, the percentage of sites with PPD >or= 5, 6 and 7 mm did not differ significantly, although mean PPD was significantly greater in the Tzununa sample (P = 0.01). Mean CAL and percentage of sites with CAL >or= 4, 5, 6 and 7 mm was significantly greater in SJLL than in Tzununa (P < 0.005) and the difference increased with age. Mean recession was also significantly greater in SJLL than Tzununa (P < 0.005), as was the percentage of sites with recession >or= 3 mm (P = 0.02), 4 mm (P = 0.002) and 5 mm (P = 0.008).

CONCLUSION

The disease levels differed between these two indigenous Guatemalan communities. Whether this has a primarily environmental or genetic basis remains to be elucidated. :

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.

Multivariate analysis of oral hygiene data from a representative sample

BACKGROUND

This analysis was based on an oral health survey with dental examination and interview by questionnaire.

METHOD

The data set comprised a representative random sample of the over 14-year-old residents of the German Federal State of Saxony (n=714), in which a multivariate logistic regression analysis was conducted. The dependent variable was the debris index (DI) score of the oral hygiene index scoring system. The subjects were split into 2 groups by dividing DI scores into tertiles: those with acceptable oral hygiene (1st tertile, DI 0.00< or =1.20) and unacceptable oral hygiene (2nd and 3rd tertile, DI>1.20). The most important explanatory variable was the community periodontal index of treatment need (CPITN).

RESULTS

The higher the CPITN score, the lower the probability of acceptable oral hygiene. In relation to the reference category score 0, higher CPITN scores were associated with acceptable oral hygiene, with an odds ratio 0.05 (95% confidence interval (CI)=0.01-0.23) for CPITN score 1, and an odds ratio 0.02 (95% CI: 0.01-0.08) for score 4. Further significant variables were: self-evaluation of tooth condition, gender, and the number of missing teeth.

Periodontal disease status of an indigenous population of Guatemala, Central America

OBJECTIVES

This study was designed to determine the periodontal disease status of an indigenous Indian community of rural Central America (San Juan La Laguna, Guatemala), for comparison with results of similar studies in other populations, and with a view to performing future studies to address familial clustering of adult periodontitis.

METHODS & RESULTS

An initial screen of 239 subjects aged 12-75 years from extended families suggested a high disease prevalence according to full-mouth pocket probing depths (PPDs), with more than 75% of subjects with one or more pockets of PPD > or =5 mm. A more detailed study was performed in 125 unrelated subjects > or =18 years, recording full-mouth PPDs and clinical attachment levels (CALs). The high prevalence of pocketing was confirmed and 90% of adults > or =35 years had at least one site with CAL > or =6 mm. However, extensive disease was restricted to a small minority, with only 10% of adults > or =35 years having 20% or more sites with CAL > or =6 mm.

CONCLUSION

The study results highlight the importance of performing a detailed examination and appropriate analysis. In both studies, tooth retention was high (mean number of teeth recorded was 26.4 and 28.0 respectively), smoking unusual, and families large and localised to the village. This community thus affords several advantages over populations in developed countries when considering familial studies of adult periodontitis.

Periodontitis

The purpose of this review was to assess the scientific and clinical bases for the proposed classification of periodontitis. The clinical and histopathological signs and the etiology of periodontitis were described. Cross-sectional studies were analyzed to determine when onset of periodontitis most frequently occurs in adults. In addition, the progression rates of periodontitis have been assessed from longitudinal studies. No clinical, histopathological, or microbiological features could be identified that would characterize different disease entities of chronic periodontitis. The prevalence, extent, and severity of periodontitis were found to increase continually with higher age and there was no age when onset of disease would most likely occur. The rate of periodontitis progression varies largely between patients and there is no natural threshold for distinguishing various rates of disease progression. The incidence of periodontitis unresponsive to treatment depends on pretreatment progression rate, extent and severity of disease, tooth type, smoking, high levels of putative periodontal pathogens, a deficient immune response, and the type of therapy provided. There is no scientific basis for the classification "adult periodontitis" and "refractory adult periodontitis." Extensive clinical examinations are required for the diagnosis of "rapidly progressive adult periodontitis." It appears unrealistic that these examinations can be performed routinely in clinical practice. Therefore, the classification proposed by the Organizing Committee to define adult, rapidly progressive, and refractory periodontitis as specific disease entities was replaced with a simplified classification of periodontitis based on the scientific data available.

Analysis of genetic polymorphisms at the interleukin-10 and tumour necrosis factor loci in early-onset periodontitis

Early onset periodontitis (EOP) is considered to have a substantial genetic basis, although the gene or genes involved have not been elucidated. The aim of the present study was to investigate possible links between generalized EOP (GEOP) and genes regulating expression of the cytokines tumour necrosis factor (TNF) and interleukin-10 (IL-10). Microsatellite marker DNA sequences corresponding to phenotypic variations in cytokine response were analysed. Genotypic variations in cytokine response have been shown in vitro for TNF and IL-10, and specific alleles are implicated in diseases such as systemic lupus erythmatosus (SLE) and rheumatoid arthritis (RA). Two microsatellites at the IL-10 locus, IL10.R and IL10.G, and 1 microsatellite at the TNF locus, TNFa, were typed for 77 GEOP patients in the West of Scotland. Due to the highly polymorphic nature of the microsatellite loci, a statistical comparison with ethnically matched healthy controls (TNFa, n = 91, IL10.R, n = 94, IL10.G, n = 102) was conducted using a Monte Carlo simulation for each marker. No significant differences were observed for any of the 3 markers, although there were possible indications of trends similar to those observed in SLE for the IL10.G marker. In conclusion, no links were found between GEOP and microsatellites at TNFa, IL10.R or IL10.G loci.

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.

Periodontal disease and tooth loss

Numerous epidemiological studies have shown that caries is the main reason for tooth loss. More recent epidemiological data seem to show an increasing trend of tooth loss due to periodontal reasons rather than caries. In considering the issue of periodontal disease and tooth loss the following observations were made. The presence of initial attachment loss, bone height and the habit of smoking significantly increase the risk of tooth mortality. There is a strong correlation between smoking, the severity of periodontal disease and tooth mortality. Cross-sectional population surveys of tooth loss reported lower anterior teeth to be the most frequently extracted due to periodontal reasons, followed by upper anteriors and upper second molars. However, in long term maintenance studies, molars were lost most frequently. Periodontal reasons for tooth loss were mainly mobility followed by furcation involvement. Periodontal surgery did not significantly enhance tooth retention in high risk groups. Ethnic differences observed were not significant and would need further investigations to address variables such as cultural differences, health habits, diet and socio-economic status. In conclusion, periodontal tooth mortality was found to be associated with the loss of periodontal attachment and risk groups with advanced periodontitis contributing to major tooth loss in a minority of the population.

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.

A 10-year study of the progression of destructive periodontal disease in adult and elderly Chinese

This study describes the progression of destructive periodontal disease among Chinese aged 20 to 80 with limited access to dental health facilities and minimal traditions for oral hygiene procedures. These individuals were followed for 10 years to determine whether the rates for progression of periodontal disease were markedly different than for populations with more access to oral health care. At baseline, participants had been examined for tooth mobility, plaque, calculus, gingival conditions, attachment levels, and probing depths on 4 sites of each tooth present. These probing depth and attachment level recordings were repeated at follow-up, although third molars were excluded from examination. A total of 398 persons remained dentate at follow-up. The analysis demonstrated that virtually all subjects experienced > or = 2 mm attachment loss over the 10-year period, and frequently in a large proportion of the sites present. Attachment loss > or = 3 mm was also widespread, but the distribution of persons according to the extent of > or = 3 mm attachment loss was positively skewed in all age groups. Positive skewness was even more pronounced when attachment loss of > or = 4 mm was considered. Some types of teeth, such as mandibular incisors and maxillary molars, had higher progression rates than did, for example, maxillary incisors. The mean individual attachment loss rates did not differ significantly between age groups, and were remarkably similar to those reported for populations whose access to and tradition for oral health care is widespread.

Predictors of destructive periodontal disease incidence and progression in adult and elderly Chinese

This study describes some predictors of new and progressing destructive periodontal disease over a 10-year period in rural Chinese. A total of 398 persons aged 20-80 years, who had participated in a baseline survey of tooth mortality, dental caries and periodontal conditions and were still dentate 10 years later, were reexamined for the same parameters as assessed at baseline. Three different threshold values were used to define new and progressing destructive periodontal disease. Irrespective of the threshold used, most persons experienced new disease. Progressing disease was very prevalent when a 2+ mm disease definition was used, but occurred less frequently at the higher threshold levels. The logistic regression models for 2+ and 3+ mm disease were essentially similar, and showed that women, persons with 104 sites or more, and persons with 0-5% sites with 4+ mm attachment levels had a lower risk of disease progression as well as of new disease than did men, persons with few sites and persons with 6% sites or more with attachment levels 4+ mm. The variables sex, number of sites present, percentage of sites with 4+ mm attachment levels, and presence of mobile teeth were predictive for new disease using a 4+ mm definition. Age, percentage of sites with 4+ mm attachment levels and percentage of sites with 4+ mm pockets were predictive for progressing disease using the 4+ mm disease definition.

Predictors of tooth loss over 10 years in adult and elderly Chinese

This study describes the incidence of tooth loss over a 10-year period in a population of rural Chinese, initially aged between 20 and 80 years. Among the 587 persons who participated in a baseline examination in 1984, 440 persons were available for a follow-up study in 1994. A total of 31 persons, mainly aged 50+ years at baseline, had become completely edentulous. Between 45% and 96% of the persons lost at least one tooth, and the average number of teeth lost ranged between 1.0 and 7.2. The distribution of the number of teeth lost was skew, indicating that a minor group of subjects had a substantially higher risk of tooth loss than the majority. Logistic regression analysis identified six significant predictors of tooth loss among those who remained dentate: age, a high number of teeth with dentinal caries lesions, a high number of teeth with caries lesions of any type, presence of teeth with attachment loss > or = 7 mm, presence of mobile teeth, and a low percentage of sites with subgingival calculus deposits. At the subject level, caries variables and periodontal disease variables seemed equally important predictors of the incidence of tooth loss over 10 years, but at the tooth level caries was a predominant cause of tooth loss in all age groups.