Risk factors for periodontitis in children and young persons

Aggregatibacter actinomycetemcomitans and its relationship to initiation of localized aggressive periodontitis: longitudinal cohort study of initially healthy adolescents

Aggregatibacter actinomycetemcomitans is frequently associated with localized aggressive periodontitis (LAP); however, longitudinal cohort studies relating A. actinomycetemcomitans to initiation of LAP have not been reported. A periodontal assessment was performed on 1,075 primarily African-American and Hispanic schoolchildren, ages 11 to 17 years. Samples were taken from each child for A. actinomycetemcomitans. A cohort of 96 students was established that included a test group of 38 A. actinomycetemcomitans-positive students (36 periodontally healthy and 2 with periodontal pockets) and 58 healthy A. actinomycetemcomitans-negative controls. All clinical and microbiological procedures were repeated at 6-month intervals. Bitewing radiographs were taken annually for definitive diagnosis of LAP. At the initial examination, clinical probing attachment measurements indicated that 1.2% of students had LAP, while 13.7% carried A. actinomycetemcomitans, including 16.7% of African-American and 11% of Hispanic students (P = 0.001, chi-square test). A. actinomycetemcomitans serotypes a, b, and c were equally distributed among African-Americans; Hispanic students harbored predominantly serotype c (P = 0.05, chi-square test). In the longitudinal phase, survival analysis was performed to determine whether A. actinomycetemcomitans-positive as compared to A. actinomycetemcomitans-negative students remained healthy ("survived") or progressed to disease with attachment loss of >2 mm or bone loss (failed to "survive"). Students without A. actinomycetemcomitans at baseline had a significantly greater chance to remain healthy (survive) compared to the A. actinomycetemcomitans-positive test group (P = 0.0001). Eight of 38 A. actinomycetemcomitans-positive and none of 58 A. actinomycetemcomitans-negative students showed bone loss (P = 0.01). A. actinomycetemcomitans serotype did not appear to influence survival. These findings suggest that detection of A. actinomycetemcomitans in periodontally healthy children can serve as a risk marker for initiation of LAP.

Prevalence of four putative periodontopathic bacteria in saliva of a group of Brazilian children with mixed dentition: 1-year longitudinal study

AIM

This study aimed at evaluating the prevalence of putative periodontal pathogens (Actinobacillus actinomycetemcomitans, Porphyromonas gingivalis, Prevotella nigrescens, Treponema denticola) in saliva of children with mixed dentition at two different time points, correlating these findings with a clinical parameter of gingival health.

DESIGN

Polymerase chain reaction (PCR) detection was used to determine the prevalence of these bacteria in saliva of 64 children in 2003 and 60 children in 2004. Gingival health was assessed by gingival index.

RESULT

Sixty-two (96.9%) and 50 (83.3%) children presented low gingival inflammation, whereas 2 (3.1%) and 10 (16.7%) had moderate scores in 2003 and 2004, respectively. Majority of the children (81.3% in 2003 and 73.3% in 2004) had detectable levels of at least one of the bacteria. The prevalence found was of 4.7% and 1.7% for A. actinomycetemcomitans, 6.3% and 8.3% for P. gingivalis, 23.4% and 48.3% for P. nigrescens (P < 0.05), and 71.9% and 50% for T. denticola (P < 0.05) in 2003 and 2004, respectively. No significant relationship between gingival index and presence of these bacteria and combination of different species was found.

CONCLUSION

A high percentage of children harboured at least one of the putative periodontal pathogens in saliva, but presented periodontally healthy conditions.

Social gradients in periodontal diseases among adolescents

OBJECTIVE

To investigate the association between socioeconomic position and periodontal diseases among adolescents.

METHODS

Data were obtained from 9203 Chilean high school students. Clinical examinations included direct recordings of clinical attachment level and the necrotizing ulcerative gingival lesions. Students answered a questionnaire on various dimensions of socioeconomic position. Seven periodontal outcomes were analyzed. Logistic regression analyses were used to identify socioeconomic variables associated with the periodontal outcomes.

RESULTS

The occurrence of all periodontal outcomes investigated followed social gradients, and paternal income and parental education were the most influential variables.

CONCLUSIONS

The study demonstrates the existence of significant social gradients in periodontal diseases already among adolescents. This is worrying, and indicates a new potential for further insight into the mechanisms of periodontal disease causation.

Epidemiology and risk factors of periodontal diseases

Periodontal diseases are chronic inflammatory disorders encompassing destructive and nondestructive diseases of the periodontal supporting tissues of teeth. Gingivitis is a nondestructive disease ubiquitous in populations of children and adults globally. Aggressive periodontitis is characterized by severe and rapid loss of periodontal attachment often commencing at or after the circumpubertal age and is more prevalent among Latin Americans and subjects of African descent, and least common among Caucasians. Chronic periodontitis is a common disease and may occur in most age groups, but is most prevalent among adults and seniors world-wide. Approximately 48% of United States adults have chronic periodontitis, and similar or higher rates have been reported in other populations. Moderate and advanced periodontitis is more prevalent among the older age groups, and rates of 70% or more have been reported in certain populations. Chronic and aggressive periodontitis are multifactorial diseases caused primarily by dental plaque microorganisms, and with important modifying effects from other local and systemic factors. The study of the significance of demographic, environmental, and biologic variables is important for risk assessment and the control of periodontal diseases.

Aggressive Periodontitis in an Urban Population in Southern Brazil

BACKGROUND

There are limited data about the epidemiology and risk factors for aggressive periodontitis (AgP) in Latin American and Brazilian populations. The aim of this study was to assess the prevalence of AgP and the risk associated with demographic variables, smoking behavior, and other periodontal variables in a young urban population in southern Brazil.

METHODS

A representative sample of 612 subjects aged 14 to 29 years were sampled using a multistage probability method. A full-mouth clinical examination of six sites per tooth and an interview were performed in a mobile examination center. Subjects in the age groups 14 to 19 years and 20 to 29 years were classified with AgP if they had four or more teeth with attachment loss > or =4 mm or > or =5 mm, respectively.

RESULTS

AgP was found in 5.5% of the subjects. The disease occurred equally among males and females, but was twice as prevalent among non-whites than whites. In the age groups 20 to 24 years and 25 to 29 years, the AgP subjects had a significantly higher prevalence of tooth loss (90.2% versus 40.4% and 86.1% versus 43.4%, P <0.01) and mean number of missing teeth (2.6 versus 0.9 and 3.4 versus 1.5, P <0.05) than subjects without attachment loss. The AgP subjects also had significantly higher percentages of sites with dental plaque (P <0.0001), gingival bleeding (P <0.05), and supragingival calculus (P <0.0001) than normal subjects. The risk for AgP was higher in the 25- to 29-year than the 14- to 19-year age groups (odds ratio [OR] = 6.2), in the low than middle or high socioeconomic status (OR = 4.5), in moderate or heavy smokers than nonsmokers (OR = 3.1), and in subjects with > or =10% versus <10% sites with supragingival calculus (OR = 3.6).

CONCLUSION

Socioeconomic status, smoking, and dental calculus were significant risk indicators of aggressive periodontitis in this population. Suitable periodontal prevention programs implementing these risk indicators may prevent or reduce the prevalence of aggressive periodontitis in this and similar populations.

Evidence of a substantial genetic basis for IgG2 levels in families with aggressive periodontitis

IgG2 is elevated in localized but not in generalized aggressive periodontitis (AgP). Exposure to pathogenic bacteria is essential for disease. Immune responses are dominated by IgG2 reactive with bacterial surface carbohydrates. We used variance component analyses to assess IgG2 heritability and determine whether genes that influence IgG2 are the same genes that influence disease susceptibility. We studied 17 Caucasian and 43 African American families with two or more localized or generalized AgP-affected members (274 subjects with IgG2 measurements). Only 16% of the variance in IgG2 was attributable to age, race, and smoking. Even with the addition of localized AgP, the model still explained only 19% of IgG2 variance. By contrast, heritability of IgG2 levels was estimated to be 38% and highly significant (P = 0.0006), demonstrating a substantial genetic basis. Bi-trait variance component analyses of IgG2 and quantitative measures of AgP indicate that different genes appear to control IgG2 levels and disease susceptibility.