Modeling Normal and Dysbiotic Subgingival Microbiomes: Effect of Nutrients.

Screening for microbiome modulators requires availability of a high-throughput in vitro model that replicates subgingival dysbiosis and normobiosis, with a tool to measure microbial dysbiosis. Here, we tested various formulations to grow health- and periodontitis-associated subgingival microbiomes in parallel, and we describe a new subgingival dysbiosis index. Subgingival plaque samples pooled from 5 healthy subjects and, separately, 5 subjects with periodontitis were used to inoculate a Calgary Biofilm Device containing saliva-conditioned, hydroxyapatite-coated pegs. Microbiomes were grown for 7 d on either nutrient-rich media-including a modification of SHI medium, brain-heart infusion (BHI) supplemented with hemin and vitamin K, and a blend of SHI and BHI, each at 3 sucrose concentrations (0%, 0.05% and 0.1%)-or nutrient-limited media (saliva with 5%, 10%, or 20% inactivated human serum). The microbiomes were assessed for biomass, viability, and 16S rRNA profiles. In addition to richness and diversity, a dysbiosis index was calculated as the ratio of the sum of relative abundances of disease-associated species to that of health-associated species. The supplemented BHI and blend of SHI and BHI resulted in the highest biomass, whereas saliva-serum maximized viability. Distinct groups of bacteria were enriched in the different media. Regardless of medium type, the periodontitis-derived microbiomes showed higher species richness and alpha diversity and clustered with their inoculum separate from the health-derived microbiomes. Microbiomes grown in saliva-serum showed the highest species richness and the highest similarity to the clinical inocula in both health and disease. However, inclusion of serum reduced alpha diversity and increased dysbiosis in healthy microbiomes in a dose-dependent manner, mainly due to overenrichment of Porphyromonas species. The modification of SHI stood second in terms of species richness and diversity but resulted in low biomass and viability and significantly worsened dysbiosis in the periodontitis-derived microbiomes. Overall, saliva with 5% human serum was optimal for replicating subgingival microbiomes from health and disease.

The association between alcohol consumption and periodontitis in southern Brazilian adults.

BACKGROUND AND OBJECTIVE: An association between alcohol consumption and periodontitis has been suggested in the literature, but the evidence is still unclear. The aim of the present study was to investigate the relationship between alcohol consumption and periodontitis in a probability sample of adults from south Brazil. MATERIAL AND METHODS: This analysis included 1115 subjects aged 18-65 years derived from a representative sample from south Brazil. Data were collected from participants from clinical examination and structured interviews. Alcohol consumption was assessed by asking participants about the usual number of drinks consumed in a week. Four categories of alcohol consumption were defined: non-drinker, ≤ 1 glass/wk, > 1 glass/wk, ≤ 1 glass/d and > 1 glass/d. Individuals with ≥ 30% teeth with periodontal attachment loss ≥ 5 mm were classified as having periodontitis. Logistic models adjusting for age, race, socioeconomic status, dental care, body mass index, self-reported diabetes and smoking were used to estimate odds ratios (OR) and confidence intervals (95% CI). RESULTS: After adjusting for co-factors, females who reported drinking > 1 glass/d were more likely to have periodontitis (OR = 3.8, 95% CI = 1.4-10.1), whereas females who reported drinking up to 1 glass/d were 50% less likely to have periodontitis (OR = 0.5, 95% CI = 0.3-0.8). No significant associations between overall alcohol intake and periodontitis were observed for males. In an exploratory analysis, wine consumption was associated with a lower likelihood of periodontitis among males (OR = 0.2, 95% CI = 0.1-0.5) but not females. CONCLUSION: The periodontal health of males and females appears to be affected differently by alcohol consumption. Moderate wine consumption may have a beneficial effect in males.

Prevalence of Aggregatibacter actinomycetemcomitans in Sudanese patients with aggressive periodontitis: a case-control study.

BACKGROUND AND OBJECTIVE: Aggregatibacter actinomycetemcomitans is considered a possible etiological agent for aggressive periodontitis. The aim of this study was to determine the prevalence of the JP2 clone and non-JP2 genotypes of A. actinomycetemcomitans in the subgingival plaque of patients with aggressive periodontitis and controls among Sudanese high-school students. MATERIAL AND METHODS: In a previous study we examined a large representative sample of students attending high schools in Khartoum, Sudan. In this population, 17 patients with aggressive periodontitis and 17 controls (14-19 years of age) consented to participate in the present study. The subjects underwent a clinical periodontal examination, and subgingival dental plaque samples were collected using paper points. The presence of the A. actinomycetemcomitans JP2 clone and non-JP2 genotypes were assessed using loop-mediated isothermal amplification (LAMP) and the PCR. RESULTS: The JP2 clone of A. actinomycetemcomitans was not detected in the subgingival plaque of either the cases or the controls. Non-JP2 types of A. actinomycetemcomitans were detected in the subgingival plaque of 12 (70.6%) patients with aggressive periodontitis and from only one (5.9%) control subject, showing a significantly higher frequency of detection in cases than in controls (p = 0.0001). The odds ratio for the detection of A. actinomycetemcomitans in the subgingival plaque of the patients with aggressive periodontitis was 38.4 (95% confidence interval: 4.0-373.0; p = 0.002). The PCR and LAMP methods showed identical results pertaining to the identification of non-JP2 types of A. actinomycetemcomitans. CONCLUSIONS: The JP2 clone of A. actinomycetemcomitans was not detected in the subgingival plaque of high school subjects in Sudan. The detection of non-JP2 types of A. actinomycetemcomitans may be a useful marker of increased risk for development of aggressive periodontitis in young subjects.

Associations between serum antibody levels to periodontal pathogens and early-onset periodontitis.

BACKGROUND: The role of antibodies to periodontal microorganisms in the development of periodontal tissue destruction is still unclear. The aim of this study was to investigate the association between serum levels of IgG, IgA, and IgM antibodies to 6 periodontal microorganisms and clinical subtypes of varying severity of early-onset periodontitis (EOP) in young African American adults. METHODS: The study group consisted of 159 African Americans aged 19 to 25 years (mean 22 years) and included 97 cases with EOP and 62 controls with no clinical signs of EOP. These subjects were selected from a nationally representative sample of adolescents who received an oral examination as part of the National Survey of Oral Health of United States Children in 1986-1987. The group was examined clinically a second time 6 years later and blood samples were collected. Serum levels of IgG, IgA, and IgM reactive to Actinobacillus actinomycetemcomitans, Porphyromonas gingivalis, Prevotella intermedia, Campylobacter rectus, Eikenella corrodens, and Fusobacterium nucleatum were assessed. RESULTS: Serum levels of IgG and IgA antibody reactive to P. gingivalis and A. actinomycetemcomitans and IgA antibody to P. intermedia were significantly higher in generalized EOP cases compared to healthy controls. IgM antibody levels did not show any significant associations with EOP for any of the 6 bacterial species tested. There were no significant differences in antibody levels between controls and the 13 subjects in our study who were classified with localized EOP. CONCLUSIONS: The findings suggest that antibodies to P. gingivalis, P. intermedia, and A. actinomycetemcomitans may play a significant role in the pathogenesis of EOP. Substantial longitudinal studies that monitor antibody levels and avidity prior to disease onset, during progression, and following clinical intervention will be necessary to fully understand the role of this component of the immune response in protection versus tissue destruction and the potential use in EOP risk assessment and disease management.

Periodontal status of adult Sudanese habitual users of miswak chewing sticks or toothbrushes.

Miswak chewing sticks are prepared from the roots or twigs of Salvadora persica plants. They are widely used as a traditional oral hygiene tool in several African and Middle Eastern countries. The aim of this study was to assess and compare the periodontal status of adult Sudanese habitual miswak and toothbrush users. The study population comprised male miswak users (n = 109) and toothbrush users (n = 104) with age range 20-65 years (mean 36.6 years) having 18 or more teeth present. They were recruited among employees and students at the Medical Sciences Campus in Khartoum, Sudan. One examiner used the Community Periodontal Index (CPI) to score gingival bleeding, supragingival dental calculus, and probing pocket depth of the index teeth of each sextant. In addition, the attachment level was measured, which, along with the CPI, was used to assess the periodontal status of the two test groups. Gingival bleeding and dental calculus were highly prevalent in the study population. Approximately 10% of the subjects had > or =4 mm probing depth and 51% had > or =4 mm attachment loss in one or more sextants. Subjects in the age group 40-65 years had a significantly (p < 0.05) higher number of sextants with gingival bleeding and with > or =4 mm probing depth and attachment loss than the 30-39 years group. Miswak users had significantly (p < 0.05) lower dental calculus and > or =4 mm probing depth and higher > or =4 mm attachment loss as well as a tendency (p = 0.09) to lower gingival bleeding in the posterior sextants than did toothbrush users. These differences were not significant in the anterior sextants. It is concluded that the periodontal status of miswak users in this Sudanese population is better than that of toothbrush users, suggesting that the efficacy of miswak use for oral hygiene in this group is comparable or slightly better than a toothbrush. Given the availability and low cost of miswak, it should be recommended for use in motivated persons in developing countries.

Cigar, pipe, and cigarette smoking as risk factors for periodontal disease and tooth loss.

BACKGROUND: Our purpose was to test the hypotheses that cigar and pipe smoking have significant associations with periodontal disease and cigar, pipe, and cigarette smoking is associated with tooth loss. We also investigated whether a history of smoking habits cessation may affect the risk of periodontal disease and tooth loss. METHODS: A group of 705 individuals (21 to 92 years-old) who were among volunteer participants in the ongoing Baltimore Longitudinal Study of Aging were examined clinically to assess their periodontal status and tooth loss. A structured interview was used to assess the participants' smoking behaviors with regard to cigarettes, cigar, and pipe smoking status. For a given tobacco product, current smokers were defined as individuals who at the time of examination continued to smoke daily. Former heavy smokers were defined as individuals who have smoked daily for 10 or more years and who had quit smoking. Non-smokers included individuals with a previous history of smoking for less than 10 years or no history of smoking. RESULTS: Cigarette and cigar/pipe smokers had a higher prevalence of moderate and severe periodontitis and higher prevalence and extent of attachment loss and gingival recession than non-smokers, suggesting poorer periodontal health in smokers. In addition, smokers had less gingival bleeding and higher number of missing teeth than non-smokers. Current cigarette smokers had the highest prevalence of moderate and severe periodontitis (25.7%) compared to former cigarette smokers (20.2%), and non-smokers (13.1%). The estimated prevalence of moderate and severe periodontitis in current or former cigar/pipe smokers was 17.6%. A similar pattern was seen for other periodontal measurements including the percentages of teeth with > or = 5 mm attachment loss and probing depth, > or = 3 mm gingival recession, and dental calculus. Current, former, and non- cigarette smokers had 5.1, 3.9, and 2.8 missing teeth, respectively. Cigar/pipe smokers had on average 4 missing teeth. Multiple regression analysis also showed that current tobacco smokers may have increased risks of having moderate and severe periodontitis than former smokers. However, smoking behaviors explained only small percentages (<5%) of the variances in the multivariate models. CONCLUSION: The results suggest that cigar and pipe smoking may have similar adverse effects on periodontal health and tooth loss as cigarette smoking. Smoking cessation efforts should be considered as a means of improving periodontal health and reducing tooth loss in heavy smokers of cigarettes, cigars, and pipes with periodontal disease.

Gingival recession, gingival bleeding, and dental calculus in adults 30 years of age and older in the United States, 1988-1994.

BACKGROUND: The aim of this study was to assess the prevalence and extent of gingival recession, gingival bleeding, and dental calculus in United States adults, using data collected in the third National Health and Nutrition Examination Survey (NHANES III). METHODS: The study group consisted of 9,689 persons 30 to 90 years of age obtained by a stratified, multi-stage probability sampling method in 1988 to 1994. The weighted sample is representative of U.S. adults 30 years or older and represents approximately 105.8 million civilian, non-institutionalized Americans. Gingival recession, gingival bleeding, and dental calculus were assessed at the mesio-buccal and mid-buccal surfaces in 2 randomly selected quadrants, one maxillary and one mandibular. Data analysis accounted for the complex sampling design used. RESULTS: We estimate that 23.8 million persons have one or more tooth surfaces with > or = 3 mm gingival recession; 53.2 million have gingival bleeding; 97.1 million have calculus; and 58.3 million have subgingival calculus; and the corresponding percentages are 22.5%, 50.3%, 91.8%, and 55.1% of persons, respectively. The prevalence, extent, and severity of gingival recession increased with age, as did the prevalence of subgingival calculus and the extent of teeth with calculus and gingival bleeding. Males had significantly more gingival recession, gingival bleeding, subgingival calculus, and more teeth with total calculus than females. Of the 3 race/ethnic groups studied, non-Hispanic blacks had the highest prevalence and extent of gingival recession and dental calculus, whereas Mexican Americans had the highest prevalence and extent of gingival bleeding. Mexican Americans had similar prevalence and extent of gingival recession compared with non-Hispanic whites. Gingival recession was much more prevalent and also more severe at the buccal than the mesial surfaces of teeth. Gingival bleeding also was more prevalent at the buccal than mesial surfaces, whereas calculus was most often present at the mesial than buccal surfaces. CONCLUSIONS: Dental calculus, gingival bleeding, and gingival recession are common in the U.S. adult population. In addition to their unfavorable effect on esthetics and self-esteem, these conditions also are associated with destructive periodontal diseases and root caries. Appropriate measures to prevent or control these conditions are desirable, and this may also be effective in improving the oral health of the U.S. adult population.

Destructive periodontal disease in adults 30 years of age and older in the United States, 1988-1994.

BACKGROUND: Accurate information on the prevalence and extent of periodontal diseases in the United States adult population is lacking. This study estimated the prevalence and extent of periodontal disease in the United States using data from the third National Health and Nutrition Examination Survey (NHANES III). METHODS: A nationally representative sample was obtained during 1988 to 1994 by a stratified, multi-stage probability sampling design. A subsample of 9,689 dentate persons 30 to 90 years old who received a periodontal examination was used in this study, representing approximately 105.8 million civilian, non-institutionalized Americans in 1988 to 1994. Periodontal attachment loss, probing depth, and furcation involvement were assessed in 2 randomly selected quadrants per person. Attachment loss and probing depth were assessed at 2 sites per tooth, the mesiobuccal and mid-buccal surfaces. The periodontal status of each subject was assessed by criteria based on the extent and severity of probing depth and furcation involvement. These assessments were used to classify each subject as having a mild, moderate, or advanced form of the disease. In the analyses, weighted data were used to reflect the complex sampling method. RESULTS: Prevalence of attachment loss > or = 3 mm was 53.1% for the population of dentate U.S. adults 30 to 90 years of age and, on average, 19.6% of teeth per person were affected. The prevalence of probing depth > or = 3 mm was 63.9% and, on average, 19.6% of teeth were affected. Fourteen percent of these persons had furcation involvement in one or more teeth. We estimate that at least 35% of the dentate U.S. adults aged 30 to 90 have periodontitis, with 21.8% having a mild form and 12.6% having a moderate or severe form. The prevalence and extent of attachment loss and the prevalence of periodontitis increase considerably with age. However, the prevalence of moderate and advanced periodontitis decreases in adults 80 years of age and older. This is most likely attributed to a combination of a high prevalence of tooth loss and gingival recession in the oldest age cohorts. Attachment loss and destructive periodontitis were consistently more prevalent in males than females, and more prevalent in blacks and Mexican Americans than whites. We estimate that in persons 30 years and older, there are approximately 56.2 and 67.6 million persons who, on average, have about a third of their remaining teeth affected by > or = 3 mm attachment loss and probing depth, respectively. We also estimate that about 21 million persons have at least one site with > or = 5 mm attachment loss, and 35.7 million persons have periodontitis. These are conservative estimates based on partial-mouth examinations, and the true prevalence and extent of periodontal disease may be significantly higher than what is reported here. CONCLUSIONS: Periodontitis is prevalent in the U.S. adult population. The results show that black and Mexican American males have poorer periodontal health than the rest of the U.S. adult population. Primary and secondary preventive measures should therefore be specifically targeted towards these groups.

Crevicular fluid level of beta-glucuronidase in relation to clinical periodontal parameters and putative periodontal pathogens in early-onset periodontitis.

Analysis of beta-glucuronidase (betaG) in the gingival crevicular fluid (GCF) provides an indication of neutrophil influx into the crevicular environment. The aim of this study was to test the hypotheses that: (1) betaG is significantly elevated in individuals with early-onset periodontitis (EOP) and that betaG activity correlates with disease severity; and (2) betaG level may reflect the local bacterial challenge in the gingival crevice. The study subjects consisted of a sub-sample of individuals examined in the National Survey of Oral Health of United States Children, which was undertaken during the 1986/87 school year. A total of 249 individuals were selected based on presence or absence of clinical attachment loss at baseline. The individuals were examined a second time 6 years later and the clinical attachment loss was assessed, and subgingival plaque and GCF were collected. The subjects were classified into 3 types of EOP and a control group. BetaG activity in the GCF and the levels of 7 putative micro-organisms in the pocket were assessed. The generalized EOP group had the highest betaG activity, followed by the localized and incidental EOP groups, and the controls, respectively. There was a significant increase in betaG activity with the increase in probing depth. Also, sites with bleeding on probing had a significantly higher betaG activity than sites without bleeding. However, the effect of gingival inflammation on betaG activity was more evident in the generalized and localized EOP groups. Sites harboring high levels of one or more of the micro-organisms tended to have high betaG activity. There were moderate differences between the organisms with respect to their effect on betaG activity, but sites with high numbers of Porphyromonas gingivalis, Prevotella intermedia, or Treponema denticola also had the highest betaG activity. The present findings suggest that betaG activity in GCF from patients with EOP can be of value in the early identification of individuals at higher risk of developing EOP The findings also suggest that host mechanisms leading to higher betaG activity in EOP represent systemic responses and are only partly related to the presence of local factors at the site-level.

Gingival inflammation and subgingival calculus as determinants of disease progression in early-onset periodontitis.

This study was undertaken to test the hypothesis that gingival inflammation and dental calculus are important determinants of the development and progression of early-onset periodontitis. The study sample included 156 individuals who were 13-20 years old at baseline and who were examined 2x during 6 years to assess the attachment loss, gingival state and the presence of dental calculus. 33 (21%), 62 (40%), and 61 (39%) individuals were classified as having localized, generalized, or incidental EOP, respectively. The results showed an increase in the % of teeth with overt gingivitis and subgingival calculus, and also an increase in the % of teeth showing attachment loss during the 6-year period in all classification groups. Of teeth with 0-2 mm attachment loss at the beginning of the study and which developed > or = 3 mm attachment loss during the following 6 years, there were 2x as many teeth with overt gingival inflammation, and 4x more teeth with subgingival calculus at baseline than teeth without. Gingivitis and subgingival calculus when present at both examinations resulted in a stronger association with the development of new lesions than presence of these variables at baseline. Teeth with gingivitis at baseline had a significantly higher mean attachment loss during 6 years than teeth without gingivitis (p<0.0001), and teeth with subgingival calculus at baseline had a significantly higher mean attachment loss than teeth without subgingival calculus (p<0.0001). The presence of gingivitis and subgingival calculus at baseline and 6 years later was associated with the occurrence of even higher disease progression during this period. The association between gingival inflammation and subgingival calculus and the development and progression of attachment loss during the study period in the generalized and the localized EOP groups was significantly higher than the association in the incidental EOP group. In an appreciable % of the sites in all 3 groups, however, the presence of the 2 factors was not associated with attachment loss during 6 years. The results suggest a significant association between gingival inflammation and subgingival calculus and the development and progression of early-onset periodontitis.

Putative periodontal pathogens in subgingival plaque of young adults with and without early-onset periodontitis.

This study assessed the associations between putative periodontal pathogens and early-onset periodontitis (EOP) in a population of 248 subjects, 13 to 19 years of age at baseline, derived from a representative sample of U.S. young adults. The subjects were selected based on the presence or absence of attachment loss at baseline. The attachment level was assessed clinically at baseline and at a 6-year follow-up examination, and the presence of 7 bacterial species was assessed at follow-up using DNA probes. The individuals were classified into generalized, localized, incidental EOP, and no-periodontitis groups based on the extent and severity of attachment loss; and classified as having rapid, moderate, slow, and no progression based on the rate of periodontal progression during the 6 preceding years. In the EOP groups there were significantly higher percentages of individuals with detectable levels of Porphyromonas gingivalis, Prevotella intermedia, Fusobacterium nucleatum, Campylobacter rectus, and Treponema denticola. In addition, the EOP group had significantly higher levels of these 5 microorganisms compared to the no-periodontitis group. There were also higher percentages of individuals with these species and higher levels of bacteria in the group showing disease progression than the group without progression. In a descending order of importance, P. gingivalis, T. denticola, and P. intermedia were the microorganisms significantly associated with the generalized and/or rapidly progressing disease. F. nucleatum and C. rectus were also associated with EOP, but to a lesser degree. In the present population Actinobacillus actinomycetemcomitans was not significantly associated with EOP, though it was recovered more often from subjects with localized EOP. Eikenella corrodens was present equally in subjects with and without disease. The results show that several bacterial species are associated with EOP, and that P. gingivalis and T. denticola are of particular importance and may play a significant role in the more severe and progressive forms of EOP.

Clinical features of early-onset periodontitis.

The authors estimate the prevalence of early-onset periodontitis, or EOP, in U.S. adolescents and describe the clinical features that occur at an early stage in those who have EOP. In 1986 and 1987, about 10.0 percent of African-American, 5.0 percent of Hispanic and 1.3 percent of white U.S. adolescents had EOP. Clinical features that may be useful in the early detection of EOP include overt gingival inflammation, dental calculus and a high rate of caries, restorations and tooth loss.

Clinical classification of periodontitis in adolescents and young adults.

THE AIM OF THIS STUDY was to determine the degree to which clinical classifications based on cross-sectional assessments endure in the course of development of early-onset periodontitis (EOP), and to introduce new criteria which might improve the clinical classification of these diseases. Subjects with EOP and a matched group without EOP were identified within a national probability sample examined during the 1986/87 survey of US schoolchildren. Of these, 265 subjects (mean age 16 years) were re-examined during the 1992/93 school year. The clinical attachment level of teeth was assessed, and the individuals were classified into localized juvenile periodontitis (LJP), generalized juvenile periodontitis (GJP), incidental attachment loss (IAL), and no-periodontitis groups using three classification methods previously described. A fourth method that considered the extent and severity of attachment loss and the number of missing teeth was introduced to classify the individuals at baseline and at follow-up as having localized, generalized, or incidental EOP, and no-periodontitis groups. Furthermore, the individuals were classified using criteria based on the rate and pattern of change in attachment loss during 6 years. The results showed low correlations between the baseline classifications and the classifications at the 6-year follow-up examination, irrespective of the method used. In addition, the cross-sectional classifications were not predictive of the rate of progression of periodontal disease in these subjects. In the generalized disease group, two-thirds of the individuals exhibited moderate/rapid disease progression, while one-third had slow or no progression. In the localized disease group, one-half of the individuals had moderate/rapid disease progression and one-half had slow or no progression. In the incidental disease group one-fourth of the individuals had moderate/rapid disease progression and three-fourths had slow or no progression. We propose that the term early-onset periodontitis be used as a generic term to describe periodontal disease before its normal onset. In addition, we suggest that incidental, localized, and generalized EOP are heterogenous groups comprising rapidly and slowly progressing forms within each classification. The findings suggest that a classification system in which subsets of the disease that are defined according to a combination of cross-sectional criteria and the disease progression may be useful in studies of EOP. Furthermore, the findings suggest that clinical classifications of EOP be used as generic descriptors until a full understanding of the pathogenesis of this disease is accomplished.

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.

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.

Early-onset periodontitis: progression of attachment loss during 6 years.

We studied the pattern of progression of early-onset periodontitis and the change in the extent and severity of the periodontal condition in adolescents who were followed for 6 years. In a national survey of the oral health of U.S. children, 14,013 adolescents were examined clinically in 1986/1987 to assess the periodontal attachment loss of teeth. Individuals with early-onset periodontitis within this population were identified and classified into localized juvenile periodontitis (LJP), generalized juvenile periodontitis (GJP), and incidental attachment loss (IAL) groups. Ninety-one subjects, 13 to 20 years old at baseline, were examined 6 years later. They included 51 males and 40 females; and 72 Blacks, 6 Hispanics, and 13 Whites. They were clinically re-examined and then reclassified according to their periodontal status at follow-up. The severity and extent of these diseases continued to increase during the study period. In teeth that were affected at baseline, the lesions had progressed to include deeper portions of the periodontium, and more of the teeth unaffected at baseline exhibited periodontal attachment loss at follow-up, thus changing the disease characteristics and the basis for the clinical classification. Of the individuals classified with LJP at baseline, 62% continued to have LJP 6 years later and 35% developed GJP. Of those classified with GJP initially, all but two (82%) continued to have GJP at follow-up. Among the IAL group, 28% of subjects developed LJP or GJP, and 30% were reclassified in the no attachment loss group. Molars and incisors were the teeth most often affected in all three groups. The mean change in attachment loss over 6 years in the LJP, GJP, and IAL groups was 0.45, 1.12, and 0.13 mm, respectively. The present findings demonstrate the limitations of the currently used morphological criteria in the classification of early-onset periodontitis. The findings also suggest that the difference between LJP and GJP is in the number and type of teeth involved, and that the two classifications progress similarly, with some cases of LJP developing into GJP.

Bone density changes after 1 year in periodontal lesions treated surgically with or without ePTFE membrane placement.

The present study was designed to quantitatively assess radiographic changes in alveolar bone density in intrabony defects treated with expanded polytetrafluorethylene membranes (ePTFE) or by conventional flap surgery alone. 15 patients with 2 periodontal defects of comparable morphology which could be depicted on a single radiograph made up the test panel. Standardized radiographs of the periodontal defects were taken immediately prior to surgery and 12 months later. The 2 defects were treated simultaneously using the modified Widman flap procedure and prepared for membrane placement. Then one of the lesions was randomly assigned for treatment with the membrane. All radiographs and surgical procedures were managed by one person. The radiographs were assessed by another person according to a blind design. Periodontal defects treated with ePTFE membranes (test), and sites treated by conventional flap procedures (control) were then analyzed using a computerized image analysis program. In 8 patients, the test site outcome was better than the outcome in the control site. 6 of the control sites indicated increased bone density, while 7 sites showed decreased values, and 2 sites were unchanged. The corresponding values from the test sites were 5, 6 and 4, respectively. In the present controlled clinical study, the use of an ePTFE membrane to cover the opening of a vertical bone defects during periodontal surgery did not predictably increase the bone density of the defects.

PCR primers for the amplification of the 16S rRNA gene of oral bacteria and for the specific identification of Actinobacillus actinomycetemcomitans.

The aim of this study was to develop a PCR reaction specific to Actinobacillus actinomycetemcomitans, which targets a widely conserved gene of this bacterium. Two sets of primers were designed based on published sequences of the 16S rRNA of several microorganisms. The first set amplifies a major part of the 16S small subunit rRNA gene of several strains of bacteria commonly found in the periodontal pocket. This reaction produced a 1306 bp-long product and served as a positive control. The second set was specific to A. actinomycetemcomitans and produced a 449 bp-long product. H. aphrophilus and E. coli yielded positive results with the control primers and negative results with the A. actinomycetemcomitans-specific primers. DNA-DNA hybridization was used to validate the identify of the amplified sequences. B. cereus, which is a common contaminator in the laboratory, and human DNA did not generate PCR products in either reaction. The developed primers seen useful for the identification of A. actinomycetemcomitans strains.

Caries lesions and dental restorations as predisposing factors in the progression of periodontal diseases in adolescents. A 3-year longitudinal study.

The present study used a novel approach to assess the relationship between untreated caries lesions and defective and non-defective dental restorations and the incidence of gingival inflammation and the progression of chronic inflammatory periodontal diseases at the approximal surfaces of posterior teeth and at the adjacent surface of the neighboring tooth in adolescents over a period of 3 years. Two hundred-twenty-seven (227) 13-year-old schoolchildren were examined clinically and radiographically at baseline and annually at three subsequent occasions. At each site the alveolar bone height and presence of gingival bleeding were assessed. Incipient caries lesions, manifest caries, and defective and non-defective restorations were identified at the same site and also at the adjacent approximal tooth surface at all examinations, both clinically and radiographically. The data were analyzed by the multi-level logistic regression and variance components analyses. On average, 32, 8.5, 7, and 10% of the sites, respectively, were diagnosed as having incipient caries, manifest caries, and defective and non-defective restorations. There was a significant association between the presence of untreated manifest caries lesions, non-defective and defective dental restorations, and the progression of periodontal support loss. Also there was an association between presence of defective restorations and manifest caries and the incidence of gingival inflammation. Consistently, factors detected at the involved site and at the adjacent site had significant effects. The present study indicates that untreated cavities and dental restorations are predisposing factors with a significant negative effect on periodontal health in adolescents.(ABSTRACT TRUNCATED AT 250 WORDS)