Association between the IL-10 rs1800872 polymorphisms and periodontitis susceptibility: A meta-analysis

BACKGROUND

Periodontitis is a common disease with an unclear pathological mechanism. No precise consensus has been reached to evaluate the association between the IL-10 rs1800872 (- 592, -590, -597 C>A) polymorphism and periodontal disease. Thus, we performed this meta-analysis to collect more evidence-based information.

METHODS

Four online databases, PubMed, Embase, Web of Science, and China Biology Medicine disc (CBM), were searched in August 2018. An odds ratio (OR) with a 95% confidence interval (CI) was applied to evaluate the association of the rs1800872 with periodontitis susceptibility.

RESULTS

Twenty three case-control studies with 2714 patients and 2373 healthy controls were evaluated. The overall analyses verified that the IL-10 rs1800872 polymorphism was significantly associated with an increased risk of periodontitis in the allelic model, homozygote model, dominant model, and recessive model (A vs C: OR = 1.28, 95%CI = 1.11-1.49, P = .00, I = 56.87%; AA vs CC: OR = 2.06, 95%CI = 1.32-3.23, P = .00, I = 73.3%; AA + AC vs CC: OR = 1.42, 95%CI = 1.03-1.96, P = .03, I = 76.2%; AA vs AC + CC: OR = 1.78, 95%CI = 1.26-2.56, P = .00, I = 76.7%). Moreover, the subgroup analysis based on ethnicity, periodontitis type, and smoking status showed significant differences.

CONCLUSIONS

The results of our meta-analysis demonstrate that rs1800872 is associated with periodontitis susceptibility in Caucasians and Asians. Moreover, A allele, AA genotype, CC genotype may be closely associated with chronic periodontitis (CP), while A allele, AA genotype may be closely associated with aggressive periodontitis (AgP).

[Genetic background of periodontitis. Part I. Basic principles and inherited syndromes. Literature review]

Periodontitis is an infectious disease. It had previously been considered as a diseases caused merely by dental plaque. During the 1990-ies a substantial number of publications indicated the role of other risk factors in its pathogenesis, such as behavioral, systemic and genetic causes. Based on recent research data, genetic and ethnic factors have become the leading susceptibility or severity factors for destructive periodontitis. The family background of early onset aggressive periodontitis has long been known. Hereditary syndromes can very frequently be associated with severe periodontitis. Both facts can support the alleged connection between certain genes' mutation and periodontal manifestation. Periodontal disease associated with systemic hereditary syndromes mainly shows a Mendelian inheritance. The locus and the characteristics of the gene mutations have in many cases been identified. Nevertheless several polygenic gene single nucleotide mutations can also be a predisposing or severity factor for periodontitis. Part I of the literature review is focusing on those syndromes in which major PMN leukocyte deficiency or dysfunction or certain structural protein deficiency occur.

Aggressive Periodontitis Among Young Israeli Army Personnel

BACKGROUND

The aim of this study was to assess the prevalence of aggressive periodontitis among young Israeli army recruits and to evaluate its association with smoking habits and ethnic origin.

METHODS

The study population consisted of 642 young army recruits (562 men [87.5%] and 80 women [12.5%]), aged 18 to 30 years (average: 19.6 +/- 1.6 years), who arrived at a military dental clinic for dental examinations between January and December 2004. Subjects filled out a questionnaire regarding their ethnic origin and family periodontal history, followed by radiographs and a clinical periodontal examination of four first molars and eight incisors.

RESULTS

Aggressive periodontitis was found in 5.9% of the subjects (4.3% localized and 1.6% generalized). At least one site with a probing depth > or =5 mm was found in 20.1% of the subjects. A radiographic distance between crestal bone height and the cemento-enamel junction >3 mm was found in 43 (6.7%) subjects. Current smokers (39.9%) (P = 0.03) and subjects of North African origin (P <0.0001) correlated with a high prevalence of aggressive periodontitis.

CONCLUSION

A relatively high prevalence of aggressive periodontitis was found in young Israeli army recruits, which was particularly associated with smoking and ethnic origin.

The Fcgamma receptor genotype as a risk factor for generalized early-onset periodontitis in Japanese patients

BACKGROUND

Genetic polymorphisms of immunoglobulin G (IgG) Fc receptors (FcgammaR) were recently shown to be associated with recurrence rates of adult periodontitis (AP). The purpose of this study was to evaluate whether FcgammaR polymorphisms are also associated with generalized early-onset periodontitis (G-EOP) in Japanese patients.

METHODS

Thirty-eight Japanese patients with G-EOP and 83 Japanese patients with AP were identified according to established clinical criteria, including measurements of probing depth, clinical attachment level, and alveolar bone level. FcgammaR genotypes for 3 bi-allelic polymorphisms were determined in these G-EOP and AP patients and 104 race-matched healthy controls by means of allele-specific polymerase chain reactions.

RESULTS

There was a significant difference in the distribution of FcgammaRIIIb genotypes between G-EOP patients and healthy controls (P = 0.02). Additionally, a significant over-representation of FcgammaRIIIb-NA2 allele was observed in G-EOP patients as compared to AP patients and controls (P= 0.02, P= 0.009, respectively). Moreover, we found a strong association between G-EOP and the composite genotype comprising FcgammaRIIIb-NA2 and FcgammaRIIIa-158F (G-EOP versus controls: odds ratio 2.4, 95% CI 1.0-6.0, chi2 = 4.13, P= 0.04).

CONCLUSIONS

This study indicates that the FcgammaRIIIb-NA2 allele and possibly FcgammaRIIIa-158F could be associated with susceptibility to G-EOP in Japanese patients.

Clinical and genetic analysis of a large North European Caucasian family affected by early-onset periodontitis

Genetic studies of early-onset periodontitis (EOP) are hampered by several factors. These include delayed onset of the trait, an upper age limit of expression of the disease, and lack of phenotypic information for edentulous family members. Segregation analyses of families with EOP support a major locus hypothesis but fail to define clearly the criteria used for diagnosis of the relatives. Confirmation of a proposed mode of inheritance and the identification of risk genes is awaited by means of family linkage studies. It is suggested that a system can be developed for the current and retrospective diagnosis of relatives of EOP probands. In addition, it is hypothesized that the large family presented here is suitable for a linkage study. Relatives of the proband who were unavailable for a full periodontal examination, were edentulous, or were deceased, were diagnosed by means of documented clinical evidence of periodontal disease or from reported case histories. Segregation analysis was performed. Analysis of the power of the pedigree to detect linkage was carried out by means of the SIMLINK program. Three different categories were defined according to the reliability of diagnosis of EOP. Segregation analysis indicated either autosomal-dominant or X-linked-dominant inheritance in this family. The simulations showed lod scores above 3.0 for all locations of the disease gene, and for each category of diagnosis. In conclusion, a method has been developed which can be used for the diagnosis of relatives of EOP probands when ideal clinical data are unavailable. The simulations suggest that this family is suitable for a genetic linkage study with the aim of identifying the location of one or more susceptibility genes.

Absence of an especially toxic clone among isolates of Actinobacillus actinomycetemcomitans recovered from army recruits

Actinobacillus actinomycetemcomitans is a major periodontal pathogen which is associated with early-onset and adult periodontitis. The organism has been shown to be widely distributed among dentate, healthy individuals as well. It has been demonstrated that A. actinomycetemcomitans shows great genetic diversity. An especially virulent clone of the organism (JP2-like) with a specific 530-base pair (bp) deletion in the promoter region of the leukotoxin gene has been isolated from localized juvenile periodontitis patients and related subjects of African and African-American origin. The aim of the present study was to examine the presence of this specific clone employing specific oligonucleotide primers in a polymerase chain reaction among 51 isolates of A. actinomycetemcomitans recovered from 201, 18- to 25-year-old recruits with no or minor periodontal disease. In addition, clinical isolates from 37 periodontitis patients were analyzed as well as reference strains ATCC 29524, NCTC 9710, Y4 and JP2. Primers amplifying a specific 285-bp amplification product in the ltxA region of the leukotoxin gene and a specific 547-bp amplification product of 16 S rRNA were used to genetically confirm identification of the organisms. Primers amplifying sequences in the leukotoxin promoter region were used to identify the deletion. Species specific primers definitively identified all A. actinomycetemcomitans isolates. No isolates from army recruits or the reference strains displayed the deletion in the leukotoxin promoter region. However, in the periodontitis group, a 24-year-old individual from Ghana with localized juvenile periodontitis was identified with an intraoral infection with highly toxic A. actinomycetemcomitans (JP2-like). Present results confirm previous observations of absence of a highly toxic clone of A. actinomycetemcomitans among periodontally healthy and diseased Caucasians as well as a possible presence in localized juvenile periodontitis in individuals of African origin.

Linkage disequilibrium of interleukin-1 genetic polymorphisms with early-onset periodontitis

BACKGROUND

Genetic polymorphisms at interleukin (IL)-1alpha and IL-1beta were recently suggested to be associated with severity of adult periodontitis. We evaluated whether these polymorphisms might also be associated with early-onset periodontitis (EOP) in 28 African American families and 7 Caucasian American families with 2 or more affected members.

METHODS

Genomic DNA from peripheral blood was amplified, followed by restriction endonuclease digestion and acrylamide gel electrophoresis to distinguish alleles of different fragment sizes. Genetic epidemiological methods suitable for family data were used that are robust to false-positive findings due to mismatching of cases and controls or mixed subpopulations of different ethnic or geographic origin. The 2 major EOP subtypes, localized juvenile periodontitis (LJP), and generalized early-onset periodontitis (G-EOP, encompassing rapidly progressive periodontitis and generalized juvenile periodontitis), were analyzed both separately and together.

RESULTS

We obtained highly significant evidence of linkage disequilibrium for both African American and Caucasian G-EOP subjects. A similar trend was noted for LJP. The IL- alleles associated with high risk of EOP had been suggested previously to be correlated with low risk for severe adult periodontitis. Disequilibrium with G-EOP was equally strong for smoking and non-smoking subjects. IL-1alpha and IL-1beta polymorphisms were in strong disequilibrium with each other in Caucasians, but not in African Americans. Haplotype analyses evaluating both polymorphisms simultaneously indicated that the IL-1beta variant is likely to be most important for EOP risk. Sibpair linkage analyses, by contrast, provided only marginal support for a gene of very major effect on EOP risk attributable to these IL-1 polymorphisms.

CONCLUSIONS

Recent theoretical analyses indicate that our findings are most consistent with an interpretation of EOP as a complex, oligogenic disorder, with IL-1 genetic variation contributing an important but not exclusive influence on disease risk.

Serum immunoglobulin G responses to various Actinobacillus actinomycetemcomitans serotypes in a young ethnographically heterogeneous periodontitis patient group

Sera from young patients with periodontal diseases have been shown to often contain highly elevated antibody levels to Actinobacillus actinomycetemcomitans, in particular serotype b. Such responses were reportedly predominated by antibodies of the immunoglobulin G2 (IgG2) subclass. The aim of this study was to investigate an ethnically diverse group of 14 early-onset periodontitis and 15 rapidly progressive periodontitis patients for the occurrence of elevated antibody titers against the five known A. actinomycetemcomitans serotypes, and to compare the patient's IgG subclass response profiles. Enzyme-linked immunosorbent assays were used to measure both total IgG and subclass specific IgG titers. Twenty-four subjects had markedly elevate total IgG levels against at least one serotype. The frequencies of high responses against serotypes a, b, c, d and e were 7, 11, 6, 4, and 4, respectively. Elevated antibody responses were predominated by IgG2, regardless of the serotype to which the response was directed. The serotype specificity of the host responses was further investigated by competitive binding studies with serotype-specific monoclonal antibodies. Twelve sera were found to contain antibodies capable of strongly inhibit the binding of monoclonal antibodies against a single serotype; four other sera had antibodies against epitopes of two, and one serum against those of three serotypes. The findings document broad serotype diversity in an ethnically heterogeneous group of patients and indicate that strong antibody responses to A. actinomycetemcomitans are predominated by IgG2 regardless of the serotype of the infective agent.

The detection of Actinobacillus actinomycetemcomitans, Porphyromonas gingivalis and Prevotella intermedia using an ELISA in an adolescent population with early periodontitis

The aim of the study was to compare the occurrence and levels of A. actinomycetemcomitans, P. gingivalis, and P. intermedia in the subgingival plaque from sites with and without early periodontitis in adolescents using an ELISA. 47, 15- to 16-year-old adolescents (39 Indo-Pakistani, 8 white Caucasian) were examined for clinical attachment level, probing depth, supragingival plaque, subgingival calculus and bleeding on probing on the mesio-buccal and disto-buccal aspects of the 1st molars and the incisors. Based on the clinical data, 2 sites per subject were selected for subgingival plaque sampling 3 weeks later: in 32 subjects with loss of attachment > or = 1 mm, a diseased site (D) and a healthy comparison control site (C) were sampled; in 15 subjects in whom loss of attachment had not yet developed, 1 of the upper molar sites was selected, called the at-risk site (R), together with a C site. The presence and levels of A. actinomycetemcomitans, P. gingivalis, and P. intermedia were determined using an ELISA. The loss of attachment subgroup had significantly more pockets > or = 4 mm, subgingival calculus and bleeding on probing (p < 0.05). Significantly more of the D than C sites had P. gingivalis both at detectable and at measurable levels (p < 0.05). In subjects who had no loss in clinical attachment levels, fewer sampled sites harboured any of the suspected periodontopathogens investigated, and no significant differences were found between the R or C sites (p > 0.05). Although there was a significantly higher prevalence and extent of loss of attachment > or = 1 mm in the Indo-Pakistani subjects compared with the Caucasians (p < 0.05), no differences could be identified in the distribution of the bacteria. It is concluded that monitoring of the subgingival plaque may be useful in studies of early periodontitis in adolescents, and the role of P. gingivalis needs to be elucidated in prospective longitudinal investigations.

Dental caries and tooth loss in adolescents with early-onset periodontitis

The aim of this study was to assess the caries experience and tooth loss over 6 years in subjects with early-onset periodontitis as compared to their matched controls, and to describe the characteristics of teeth lost during this period. A multi-stage probability sample representing 8th to 12th grade U.S. schoolchildren were screened during the 1986/1987 school year to identify subjects with early-onset periodontitis (cases). The examination included measuring the clinical attachment level, presence of caries and dental restorations, and tooth loss. A random sample of controls without early-onset periodontitis were selected for a follow-up examination and were matched to cases on gender, race, age, and geographic location. A total of 266 subjects, with a mean age of 16 years at baseline, were examined during the 1992/1993 school year and were classified into localized (LJP) and generalized juvenile periodontitis (GJP), incidental attachment loss (IAL), and control groups. Whites had more caries experience than Blacks and Hispanics, but there were no significant differences in tooth loss between the ethnic groups. The LJP and the IAL groups, respectively, had higher and lower overall caries experience than the control group. The LJP group had a significantly higher number of missing teeth at follow-up, and exhibited more extensive tooth mortality during 6 years than the control group. The GJP group also showed more tooth loss than the control group, but the difference was not statistically significant. In the LJP, GJP, IAL, and control groups, respectively, 43%, 32%, 26%, and 18% of the subjects lost teeth over 6 years due to disease. The findings showed differences in caries activity between the early-onset periodontitis groups and a variation by race. The findings suggest that loss of periodontal support was the principal cause for tooth loss in the LJP and GJP groups, and that dental caries was the principal cause for tooth extraction in the IAL and the control groups.

Gingival state and dental calculus in early-onset periodontitis

This study was undertaken to 1) compare the prevalence of gingival inflammation and dental calculus in adolescents with early-onset periodontitis and their matched controls and 2) assess and compare the relationship between the presence of dental calculus and the extent of gingival bleeding and attachment loss in these subjects. The study group consisted of 1,285 13 to 20 year-old individuals, 651 males and 634 females, selected from a national survey of the oral health of U.S. adolescents in 1986/1987. It included 709 (55.2%) Blacks, 224 (17.4%) Hispanics, and 352 (27.4%) Whites. Eighty-nine subjects had localized or generalized juvenile periodontitis (JP), 218 had incidental attachment loss (IAL), and 978 were without clinical attachment loss (controls). The controls were matched to cases on gender, race, age, and geographic location. The subjects were examined clinically to assess the percentage of sites with gingival bleeding and supragingival calculus only and subgingival calculus with or without supragingival calculus. The IAL and JP groups had significantly more gingival bleeding and subgingival calculus than the controls. Also, the JP group had significantly higher prevalence of both conditions than the IAL group. The percentage of sites with supragingival calculus was not different between the groups, but varied by ethnicity. Hispanics with JP had the highest percentage of sites with gingival bleeding and subgingival calculus, and the lowest percentage of sites with only supragingival calculus. The results demonstrate that gingival inflammation and subgingival calculus are associated with early periodontal breakdown, and contradict earlier reports of early-onset periodontitis not being associated with these factors.

Serum immunoglobulin G subclass concentrations in periodontally healthy and diseased individuals

Patients with localized juvenile periodontitis (LJP) often have high titers of antibody reactive with the serotype-specific immunodominant carbohydrate antigen of Actinobacillus actinomycetemcomitans serotype b. The vast majority of this A. actinomycetemcomitans serotype b-specific antibody is immunoglobulin G2 (IgG2). The present study was undertaken to determine whether the overall total levels of IgG2 in the sera of LJP patients are elevated. LJP patients and nonperiodontitis (NP) controls matched for age, race (black and white), and gender were studied. Additional controls included patients with adult periodontitis (AP) and patients similar in age to LJP patients but with the more-severe, generalized form of early-onset periodontitis (SP). Sera from over 700 periodontally characterized subjects were examined by using radial immunodiffusion to quantitate IgG2 as well as IgG1, -3, and -4, which were included for comparison. Serum IgG2 levels increased with age, and this was most dramatic around puberty. Black subjects in all periodontal groups had nearly 1 mg more IgG2 per ml than their white counterparts. Serum IgG2 levels were elevated (about 30 to 40%) in LJP patients of both races compared with their age- and race-matched NP controls (P < 0.01). In contrast, SP patients and AP patients had IgG2 levels comparable to their age- and race-matched NP controls. No other IgG subclass concentration correlated with periodontal diagnosis except for IgG3, which was elevated in white LJP patients. We reason that the high levels of serum IgG2 in LJP may be helpful in localizing periodontal destruction.

Early-onset periodontitis in Hispanic-American adolescents associated with A. actinomycetemcomitans

This study examines the frequency of oral disease in an adolescent population, and assesses the relationship to Actinobacillus actinomycetemcomitans. A total of 470 eighth grade students from San Antonio, Texas, were examined clinically for number of teeth, frequency of gingival inflammation, frequency of sites with BOP, and frequency of sites with 3-5 mm pockets, and pockets > 5 mm. The population ranged in age from 12 to 17 yr and was 93% Hispanic. Heavy accumulations of plaque and calculus were frequently observed and were associated with gingival inflammation, as 95.6% of the students exhibited bleeding on probing, and 99.6% of the students presented with at least on quadrant of inflammation upon visual examination. Significantly, 25.7% of the students exhibited early-onset periodontitis (EOP) with 1.7% diagnosed as LJP. Many students exhibited substantial levels of plaque and calculus, but no clinical evidence of loss of attachment. Subjects with periodontitis (EOP or LJP) presented with elevated systemic IgG antibody to A. actinomycetemcomitans serotype b and subgingival plaque samples positive for the microorganism. These results describe the prevalence of EOP/LJP in an adolescent Hispanic population from South Texas. The findings support that A. actinomycetemcomitans may represent a pathogen in periodontitis and while oral health care may be poor, contact with the microorganism appears to be required to initiate disease in this population.

The influence of race and gender on periodontal microflora

Previous studies have demonstrated that demographic characteristics of subject populations influence both the incidence of periodontal diseases and various aspects of host responses to periodontal bacteria. In this study we analyzed the components of the subgingival microflora from individuals with adult periodontitis, early onset periodontitis, gingivitis, and periodontal health as a function of gender and race (black and white). Clinical categories were analyzed individually so that there were no differences in the clinical characteristics of the sampled sites. No significant differences were noted in the subgingival microflora between males and females. When either the first two bacterial samples from each subject or all bacterial samples taken from each subject were included in the analysis, it was found that Porphyromonas gingivalis was more significantly associated with black subjects in the adult periodontitis group. When all samples were considered in the analysis, it was found that Peptostreptococcus anaerobius was associated with black subjects in the adult periodontitis group, while Fusobacterium nucleatum was associated with white subjects in both the adult periodontitis and early onset periodontitis groups. Thus a limited number of important bacterial components of the subgingival microflora are influenced by the race and diagnosis of the subject group.

Immunodominant antigens of Actinobacillus actinomycetemcomitans serotype b in early-onset periodontitis patients

Previous work with Actinobacillus actinomycetemcomitans strain Y4 (serotype b) indicates that the immunodominant antigen in high-responding patients (top 10%, 80% of which were black) is the serotype-specific antigen. In this study we examined the immunodominant antigens of A. actinomycetemcomitans strain Y4 in both black and white patients having a range of antibody titers. We sought to test the hypothesis that the immunodominant antigen in these subjects was the same antigen found in high responders. Seropositive white early-onset periodontitis (EOP) patients were selected from 99 EOP patients. Black subjects were then selected with comparable antibody titers. Double immunodiffusion and competition assays were used to determine whether reactive antibodies were A. actinomycetemcomitans serotype b-specific or whether the response was to serotype a or c. The immunodominant antigens were then determined for the patients reacting specifically to A. actinomycetemcomitans Y4 using limiting dilution analysis on Western blots. The immunodominant antigen for the A. actinomycetemcomitans Y4-specific patients appeared to be the serotype-specific carbohydrate for most subjects (19/20 or 95%, including: 13/14 black and 6/6 white patients). In conclusion, the immunodominant antigen for A. actinomycetemcomitans Y4 was the serotype-specific carbohydrate regardless of antibody titer for both black and white specifically reactive patients.

New considerations in the prevalence of periodontal disease

International surveys demonstrate that the prevalence of pocketing of 6 mm or more is between 5% and 20% for much of the world's population. A recently completed national survey of employed adults found the prevalence of gingival bleeding was 44%, the prevalence of pocketing of 4 mm or more was 14%, and the prevalence of attachment loss of 3 mm or more was 44%. Risk indicators for a higher prevalence of periodontal disease include increasing age, poor education, lack of professional dental care, previous periodontal destruction, tobacco use, and diabetes. African-Americans show a higher prevalence of juvenile periodontitis and adult periodontitis than whites. The female-to-male ratio in juvenile periodontitis may be close to 1:1. Another report during the review period suggests that periodontal disease in adults may have a strong genetic component. A doctoral dissertation demonstrated that the sensitivities of methods used in a national survey to detect pocketing and attachment loss range from 0.24 to 0.87 in a high-prevalence population.

Early onset periodontitis in the United States of America

A National Survey of the Oral Health of U.S. children aged 5 to 17 was conducted by the National Institute of Dental Research during the 1986-87 school year. Eleven thousand and seven adolescents aged 14 to 17 years received a periodontal assessment. Their patterns of loss of periodontal attachment as assessed by probing at mesial sites were used to classify adolescents as cases of early onset periodontitis. Approximately 0.53% of adolescents nation-wide were estimated to have localized juvenile periodontitis (LJP), 0.13% to have generalized juvenile periodontitis (GJP), and 1.61% to have incidental loss of attachment (LA) (greater than or equal to 3 mm on 1 or more teeth). The total number of adolescents affected were not trivial. Close to 70,000 adolescents in the U.S. were estimated to have LJP in 1986-87. More destructive GJP affected an estimated 17,000 adolescents. Another 212,000 adolescents were estimated to have incidental LA. Blacks were at much greater risk for all forms of early onset periodontitis than whites. Males were clearly more likely (4.3 to 1) to have GJP than females when other variables were statistically controlled. Gender associations were more complicated for LJP because gender interacted with race. Black males were 2.9 times as likely to have LJP as black females. In contrast, white females were more likely than white males to have the disease by about the same odds. When interactions among demographic variables exist, caution must be taken in comparing results from different studies.

Prevalence of juvenile periodontitis in Chile

The aim of this survey was to study the prevalence of juvenile periodontitis in schoolchildren aged 15-19 years in Santiago, Chile. A random sample of 2500 schoolchildren (1318 male, 1182 female) that represented the full range of different socio-economic strata and ethnic groups seen in the population of Santiago, was used. Initially, the children were screened clinically at school by assessment of probing depths around the incisors and first molars with a WHO 621 pattern probe. Children with 2 or more teeth with 5.5 mm or deeper pockets were invited for a radiographic examination comprising bitewing radiographs of molars, and periapical radiographs of incisors. Any subject with 2 mm or more alveolar bone loss was invited for a full clinical and radiographic examination. After screening, 27 subjects had a tentative diagnosis of juvenile periodontitis. 4 of these refused radiographic examination and only accepted a thorough clinical examination. 23 subjects presented themselves for the radiographic and complete clinical examination. Of the 27 subjects selected for detailed examination, 8 subjects (7 female, and 1 male) were diagnosed as having juvenile periodontitis. There was an overall prevalence of juvenile periodontitis of 0.32% with 95% confidence, which gives a range of +/- 0.10%. When prevalence was assessed by socio-economic status, juvenile periodontitis was found more commonly in low socio-economic group. The results of the current study suggest that in Chile, there might be a relationship between socio-economic status and prevalence of juvenile periodontitis, and that this disease is more frequent in women.

Juvenile periodontitis: an epidemiological study in the west Midlands of the United Kingdom

The prevalence of juvenile periodontitis was studied in a sample of 7266 school children in the cities of Coventry and Birmingham. The subjects were aged 15 to 19 years, and represented the range of different ethnic groups seen in the population of the West Midlands. A two-stage diagnostic procedure was used, whereby subjects were screened initially by assessment of probing depths around the incisors and first molars. Positive subjects were then diagnosed definitively by full clinical and radiographic examination. In both Coventry and Birmingham, there was an overall prevalence of juvenile periodontitis of 0.1%, with 95% confidence, which gives a range between 0.03 and 0.17. There was a highly significant difference in prevalence between ethnic groups, with overall prevalence figures of 0.02% for the Caucasian group, 0.8% for the Afro-Caribbean group and 0.2% for the Asian group. There was no difference in prevalence between male and female.