Adult Periodontitis Group Research Articles

Expression of cellular fibronectin mRNA in adult periodontitis and peri-implantitis: a real-time polymerase chain reaction study

Cellular fibronectin (cFn) is a type of bioactive non-collagen glycoprotein regarded as the main substance used to maintain periodontal attachment. The content of cFn in some specific sites can reflect the progress of periodontitis or peri-implantitis. This study aims to evaluate the expression of cFn messenger RNA (mRNA) in tissues of adult periodontitis and peri-implantitis by real-time fluorescent quantitative polymerase chain reaction (PCR) and to determine its clinical significance. A total of 30 patients were divided into three groups of 10: healthy, adult periodontitis and peri-implantitis. Periodontal tissue biopsies (1 mm×1 mm×1 mm) from each patient were frozen in liquid nitrogen. Total RNA was extracted from these tissues, and the content, purity and integrity were detected. Specific primers were designed according to the sequence, and the mRNA expression levels of cellular fibronectin were detected by real-time PCR. The purity and integrity of the extracted total RNA were both high, and the specificity of amplified genes was very high with no other pollution. The mRNA expression of cFn in the adult periodontitis group (1.526±0.441) was lower than that in the healthy group (3.253±0.736). However, the mRNA expression of cFn in the peri-implantitis group (3.965±0.537) was significantly higher than that in the healthy group. The difference revealed that although both processes were destructive inflammatory reactions in the periodontium, the pathomechanisms were different and the variation started from the transcription level of the cFn gene.

Association study between vitamin D receptor gene polymorphism and adult periodontitis in Korean

Adult periodontitis is a chronic inflammatory disease whose etiology is not well defined. Recent studies have shown that vitamin D receptor gene has been a candidate for the susceptibility of adult periodontitis. The purpose of this study is to investigate the frequency of Taq I restriction fragment length polymorphism (RFLP) in the vitamin D receptor gene in 141 periodontically healthy controls and 28 adult periodontitis patients. Taq I RFLP in the vitamin D receptor gene was detected by PCR amplification, followed by restriction enzyme digestion and 2% agarose gel electrophoresis. There was no significant difference in the distribution of Taq I RFLP between healthy controls and adult periodontitis group (P > 0.05). Thus, Taq I RFLP in the vitamin D receptor gene may not confer the susceptibility to adult periodontitis in Korean population. However, t allele distributions of this RFLP showed various frequencies among ethnic groups studied. Further studies in other ethnic groups will be required.

Periodontal bone loss in Chinese subjects with untreated early-onset and adult periodontitis: a cross-sectional study using digital scanning radiographic image analysis.

The purpose of this investigation was to evaluate the differences in radiographic alveolar bone loss (RABL) in Taiwanese subjects with early-onset periodontitis (EOP) and adult periodontitis (AP) using the digital scanning radiographic image analysis (DSRIA). A total of 4,262 teeth from 178 individuals (96 males and 82 females) were examined for RABL due to EOP and AP. The subjects with EOP and a comparison group with AP were identified from the Periodontal Clinic population (College of Dental Medicine, Kaohsiung Medical University). The following criteria were used to classify subjects with EOP and AP during the past 20 years. The RABL of teeth were calculated using a computer system equipped with Microstation 95 software, under 10 X magnification of the radiographs. Quantity assessment of RABL using the DSRIA showed that: (1) the means of RABL of maxillary and mandibular anterior teeth in the EOP group were significant greater than those in the AP group when the two sample t-test was used. (2) The greatest values of mean RABL of affected sites in the EOP group occurred most commonly in the first molars and mandibular incisors, whereas, in the AP group, the greatest values of mean RABL of affected sites occurred most commonly in the first and second molars. (3) Molars had the greatest mean RABL followed by incisors, premolars and canines. (4) The mean RABL increased with increasing age. We conclude that the features of naturally progressing alveolar bone loss at the molar and incisor sites in untreated subjects with the EOP and AP revealed that the mean RABL in the EOP group was faster and greater than that in the AP group.

Anti-inflammatory cytokine IL-10 and T cell cytokine profile in periodontitis granulation tissue.

Th2 cells are more abundant than Th1 cells in periodontitis lesions, but the relative importance of the Th1 and Th2 subsets in periodontal disease is not understood. In addition, the role of proinflammatory and anti-inflammatory cytokines in this disease process is unclear. Biopsies were obtained from 10 patients with early onset periodontitis (EOP) and 10 patients with adult periodontitis (AP). From all of the patients in the AP group we were able to obtain and section the gingival tissue to serve as controls. We used polyclonal monospecific antibodies to detect cells expressing IL-2, IL-4, IL-6, IL-10 and IL-15, tumour necrosis factor (TNF-alpha) and interferon-gamma (IFN-gamma) in formalin-fixed, paraffin-embedded sections of granulation tissue from periodontitis lesions. We also employed a series of oligonucleotide probes to detect cells expressing the cytokine transcripts in the same tissue biopsies. Cells that expressed IL-4 or IL-6 were more numerous than cells expressing either IL-2 or IFN-gamma. Th2 cells were more numerous in EOP and AP tissues. IL-15 substitutes for IL-2 in a number of biological activities related to the Th1 immune response, and interestingly, in periodontal lesions the IL-15-expressing cells outnumbered IL-2-expressing cells, suggesting that this is the pattern of immune regulation by T cells in the periodontium. The functional balance in the T cell subsets detected by their cytokine profiles underlies the importance of the anti-inflammatory mechanisms taking place in the diseased tissue. The numbers of inflammatory leucocytes that express the anti-inflammatory cytokine IL-10 are much more widely distributed than those that express the proinflammatory cytokines IL-6 and TNF-alpha. This study suggests that large numbers of infiltrating inflammatory cells as well as accessory cells are involved in the down-regulation of the inflammatory and immune response in periodontitis.

Altered chemotactic behavior of crevicular PMNs in different forms of periodontitis.

Polymorphonuclear neutrophils (PMN) are the predominant host defence cells in the gingival sulcus. Previous work demonstrates that the in vitro phagocytosis of crevicular cells in localised early onset periodontitis (LEOP) and generalised early onset periodontitis (GEOP) lesions is diminished. The present study extends this work by characterizing the chemotaxis function of crevicular fluid (CF) PMNs in various forms of periodontitis. We investigated 7 patients with LEOP, 11 patients with GEOP, 12 patients with adult periodontitis (AP) and 2 age- and sex-matched healthy control groups. The two deepest sites of each quadrant in test and control subjects were selected for crevicular sampling. Chemotaxis was performed in a micro chamber (moist atmosphere, 5% CO2, 37 degrees C, 30 min) using N-formyl-methionyl-leucyl-phenylalanine (FMLP, 1 x 10(-7) mol FMLP/l) as a chemoattractant. The total chemotaxis was defined as the difference between the number of cells migrating towards FMLP minus the number of cells migrating towards PBS, counted in 20 randomly selected fields. Membranes were examined microscopically at 400 x magnification. The chemotactic activity in the adult periodontitis group was significantly higher compared to the age-related control group. However, we found a statistically significant reduction of chemotactic activity in LEOP and GEOP patients compared to the controls. These results indicate an increase of chemotactic activity from CF-PMN in patients with adult periodontitis, but on the other hand, a significant reduction of chemotactic responsiveness of these cells in LEOP and GEOP lesions.

Immunohistological and morphometric analysis of intra-epithelial lymphocytes and Langerhans cells in healthy and diseased human gingival tissues

Periodontal diseases are histologically characterized by an infiltration of several inflammatory cell populations into the gingival epithelium and connective tissue, associated with degradation of extracellular matrix components. The purpose of this in situ study was to evaluate the inflammatory state of gingival tissues by the number of intra-epithelial lymphocyte (IEL) subsets and the area fraction ( A A %) occupied by collagen fibres in the upper gingival connective tissue, and also to evaluate the number of CD1a+ Langerhans cells (LC) in order to show correlation(s), if any, between these histological findings. The gingival samples were from 10 clinically healthy controls (group C), 8 patients with gingivitis (group G) and 9 with chronic adult periodontitis (group P). A quantitative evaluation of the number of cell populations (CD1a+, CD45RB+, CD3+, CD8+, CD20+, TIA-1+ and GrB+ cells) and the area fraction ( A A %) occupied by collagen fibres in the upper gingival connective tissue was made by morphometric and automated image analysis. The results showed that, compared with group C, all IEL subset numbers were significantly increased ( p<0.05) in G and P groups, CD20+ excepted. In addition, there was a significant increase in the cytotoxic TIA-1+ IEL number ( p<0.05) in group P when compared with group G. The study also showed a significant decrease in the number of CD1a+ LC in groups G and P ( p<0.02 and p<0.001, respectively) when compared with group C. No significant difference was found in CD1a+ LC number between groups G and P. The determination of coefficients of correlation ( r) with data obtained for each patient showed that in group G, CD1a+ LC number was significantly correlated with CD45RB+ ( p<0.05) and CD3+ ( p<0.01) IEL numbers whereas during periodontitis, CD1a+ LC number was significantly and inversely correlated with CD20+ ( p<0.01), cytotoxic TIA-1+ ( p<0.01) and with activated cytotoxic GrB+ ( p<0.01) IEL numbers. Moreover, in group P a significant ( p<0.05) positive correlation was shown between CD1a+ LC number and the A A % occupied by collagen fibres. This work demonstrates a decrease in CD1a+ LC number according to the severity of the periodontal disease estimated by the number of IEL and by the area fraction occupied by collagen fibres in human gingiva. The decrease of such cells could represent a way to avoid immune overstimulation.

The importance of data presentation regarding gingival crevicular fluid myeloperoxidase and elastase-like activity in periodontal disease and health status.

The enzymatic profile of gingival crevicular fluid (GCF) is being analyzed with increasing interest, but related studies lack a general consensus on most methodological points, including the appropriate mode of data presentation. GCF myeloperoxidase (MPO) and elastase-like activity (ELA) levels were spectrophotometrically determined on a total of 60 subjects who were divided into three equal subgroups as early-onset periodontitis (EOP), adult periodontitis (AP), and healthy. GCF enzyme levels were calculated and evaluated both as total enzyme activity and enzyme concentration. The correlations between these GCF enzymes and clinical periodontal status were also analyzed. With both modes of data presentation, the results regarding MPO activity were consistent. When presented either as total MPO activity or MPO concentration, the periodontally healthy group showed significantly lower MPO activity than the two patient groups (P<0.05). However, two modes of data presentation did not match when GCF ELA was concerned. When data were reported as total ELA, the healthy group exhibited lower enzyme activity (0.02 +/- 0.001 U) than EOP (0.04 +/- 0.01 U) and AP (0.06 +/- 0.02 U) groups; but when reported as concentration, the highest ELA levels were seen in the healthy group (221 +/- 31.53 nmol/min/ml), followed by AP (98.63 +/- 23.03 nmol/min/ml) and EOP (70.49 +/- 12.02 nmol/min/ml) (P<0.05). A strong-positive and significant correlation existed between GCF MPO and ELA. Correlations with clinical parameters were mostly observed with total activities. The findings of the present study confirm the relationship between GCF ELA and MPO activity and periodontal disease and also support the functional relativity between the two enzymes. Furthermore, based on these findings, it can be suggested that data presentation by use of total activity seems to be more sensitive in both the reflection of the actual enzymatic profile of GCF and also the existing clinical periodontal status. For each GCF component, the validity of different modes of data presentation should be considered.

Localized adhesion molecule expression and circulating LFA-3 levels in adult and early onset forms of periodontitis

Because of their importance in mediating cellular interactions in chronic inflammatory diseases, this study has examined the expression of a number of adhesion molecules in adult (n=11), generalized early onset (n=5) and localized early onset (n=2) forms of periodontitis. In comparison with immunostaining profiles of cryostat sections of healthy gingival tissue (n=7), the beta 1 integrins VLA-1, VLA-2 and VLA-4 were found to be up-regulated in periodontitis, with VLA-6 being markedly elevated. Although only small differences were observed in ICAM-1 and LFA-3 expression in the gingival epithelium, there was particularly notable up-regulation of these adhesion molecules within the inflammatory infiltrates of the diseased tissues. However, there were no statistically significant differences between the serum levels of a soluble form of LFA-3 in periodontitis patients (n=47) compared with healthy control subjects (n=40), although the generalized early onset and adult periodontitis groups exhibited wider ranges of circulating LFA-3. These findings show that there is localized modulation of adhesion molecule expression in the chronic inflammatory periodontal diseases studied, but that the levels of LFA-3 in the circulation nevertheless remain unaffected.

Relationship between serum antibody levels and subgingival colonization of Porphyromonas gingivalis in patients with various types of periodontitis.

Porphyromonas gingivalis is considered to be an important pathogen in periodontitis. The present study investigates the relationship between serum anti-P. gingivalis IgG antibody levels and the subgingival distribution of P. gingivalis in patients with periodontitis. We examined subgingival plaque samples from 15 patients with adult periodontitis (AP), 8 patients with early-onset periodontitis (EOP), and 6 clinically healthy individuals. The samples were collected from periodontal pockets or gingival crevices of all remaining teeth in each subject. The total number of samples was 3,024, ranging from 76 to 120 per subject. Probing depth and bleeding at each sample site were recorded. P. gingivalis was detected using a non-radioactive whole genomic DNA probe. Serum samples were taken from the subjects, and the serum anti-P. gingivalis IgG antibody titer was determined by enzyme-linked immunosorbent assay (ELISA). P. gingivalis was recovered from all AP and EOP patients, and from 3 of the 6 healthy subjects. Two significant positive correlations were observed among the subjects. The serum anti-P. gingivalis IgG antibody titer correlated with detection frequency of P. gingivalis, and the antibody titer correlated with the amount of P. gingivalis detected. Higher levels of P. gingivalis were detected in the EOP group than in the AP group. However, no significant difference was found in the serum IgG titer levels between EOP and AP patients. These findings suggest a direct relationship between the serum anti-P. gingivalis IgG levels and subgingival P. gingivalis colonization; however, the functional capabilities of IgG antibodies may vary among the various types of periodontitis patients.

Longitudinal dynamics of infection and serum antibody in A. actinomycetemcomitans periodontitis

This report describes one of the first prospective studies delineating the relationship between infection, host antibody responses and disease exacerbations and remissions in a distinct subset of periodontitis patients infected with A. actinomycetemcomitans. The design of this longitudinal study included visits for each patient approximately every 2 months for up to 3 years. Subjects (n=51) included 16 adult periodontitis (AP) and 11 early-onset periodontitis (EOP) patients with elevated serum IgG antibody to A. actinomycetemcomitans and infection with this microorganism, 12 AP patients with normal levels of anti-Aa antibody, and 12 normal subjects. MEASUREMENT OUTCOMES: Clinical parameters included a gingival index, plaque index, bleeding on probing, pocket depth, and attachment level. Disease activity was defined as loss of attachment during the monitoring intervals. Serum IgG, IgM and IgA antibody to A. actinomycetemcomitans Y4 (serotype b) was quantitated using an ELISA. Subgingival plaque samples were examined for A. actinomycetemcomitans using colony immunoblotting. Human serum IgG antibody specificities to outer membrane antigens (OMA) of A. actinomycetemcomitans Y4 were determined using Western immunoblotting. A. actinomycetemcomitans-infected AP patients had a higher frequency of teeth infected when compared to the EOP patients. However, the EOP patients exhibited a trend for higher levels of A. actinomycetemcomitans in those teeth that were infected. Active disease patients demonstrated a significantly greater frequency of infected sites, as well as significant elevations in the proportions of A. actinomycetemcomitans. Both EOP and AP groups showed significantly elevated IgG, IgM and IgA antibody to A. actinomycetemcomitans when compared to a periodontally normal group. The level of IgG antibody was significantly elevated in A. actinomycetemcomitans-positive patients with active disease, while IgA antibody was decreased in a number of the active group patients. Plaque samples derived from active sites showed a clear and significant increase in A. actinomycetemcomitans that occurred from 2-6 months prior to the identification of disease activity. Approximately 70% of the active disease patients showed an increase in IgG antibody level by 2-4 months prior to disease activity. Studies of the antigen reactivity patterns of serum IgG indicated that antibody to antigens of 65, 58, 48, 29 and 24 kDa were more frequent in patients who showed active disease, while those patients with the greatest frequency of active disease appeared to show a general decrease in the recognition of the A. actinomycetemcomitans OMA. It appears that A. actinomycetemcomitans infection relates to a particular type of disease with accompanying antibody responses that reflect periods of active disease. The dynamics of A. actinomycetemcomitans infection and the level and specificity of systemic antibody responses to this pathogen support an important contribution of the immune response to managing this infection.

Antibody responses of Porphyromonas gingivalis infected gingivitis and periodontitis subjects

Porphyromonas gingivalis demonstrates a strong association with adult periodontitis although some individuals with the infection do not experience attachment loss. Therefore differences in the immune response to this organism may be of importance to the outcome of the disease. The aim of this study was to determine whether P. gingivalis positive subjects with and without periodontal breakdown, reacted differently to P. gingivalis antigens as assessed by the pattern of serum antibody reactivity. Two highly defined groups of subjects were chosen for this study. Both demonstrated P. gingivalis in their plaque and both had responded to P. gingivalis as shown by the presence of serum antibodies. The two groups differed only in their apparent clinical susceptibility to periodontal breakdown. Western blots of P. gingivalis membrane antigens were probed with sera from the two groups to determine their reactivity to specific antigens. Analysis of the immunoblots showed that there were no differences in either the total numbers of bands, or bands recognized by the majority of subjects in the gingivitis and adult periodontitis groups. There were however, four bands recognized by the majority of the gingivitis group and not by the majority of the adult periodontitis group, there being a significant difference (P = 0.03) in the recognition of the 91.4-kDa antigen band. A further five antigens of lower molecular weight were seen by the majority of the adult periodontitis group and not by the majority of the gingivitis group. When sera were tested against purified P. gingivalis LPS, the results indicated that the five antigens seen by the majority of the adult periodontitis group had molecular weights which were in the range exhibited by the LPS antigens. These results suggest that gingivitis and adult periodontitis subjects with P. gingivalis infection, may recognize different P. gingivalis antigens.

IgG Antibody Subclass Response to Porphyromonas gingivalis Outer Membrane Antigens in Gingivitis and Adult Periodontitis

Porphyromonas gingivalis is an important oral pathogen with a strong association with adult periodontitis. Significant titers of specific IgG antibodies to P. gingivalis can be found in the sera of both gingivitis and periodontitis patients. Since IgG subclasses have different biological characteristics, the present study dealt with the serum IgG subclass response to outer membrane antigens of P. gingivalis. Western blot analysis of P. gingivalis outer membrane was carried out using 20 adult periodontitis and 20 age- and sex-matched gingivitis patients. Antibodies in sera of both adult periodontitis and gingivitis patients recognized 38 antigen bands, ranging in molecular mass from 11.1 to 161 kDa. IgG2 was the predominant antibody subclass response in both patient groups in terms of the numbers of outer membrane antigens recognized, followed by IgG3, IgG1, and IgG4. More antigens in all IgG subclasses except IgG4 were recognized in adult periodontitis cases. Of the 23 antigens identified by IgG2 antibodies, 9 were recognized predominantly in adult periodontitis and 3 in the gingivitis group. In the IgG1 subclass, 4 antigens were recognized predominantly in the adult periodontitis group while only 1 antigen was recognized significantly more in the gingivitis group. The IgG3 response identified 14 antigens ranging in molecular mass from 11.1 to 61.2 kDa in both groups. Ten antigens were recognized significantly by the adult periodontitis group. The lowest response was seen by IgG4 antibodies, with only 3 antigens of molecular mass 61.2, 52.3, and 38.8 kDa recognized, the latter two significantly in the adult periodontitis group.(ABSTRACT TRUNCATED AT 250 WORDS)

Bacterial‐Stimulated Cytokine Production of Peripheral Mononuclear Cells From Patients of Various Periodontitis Categories

Periodontitis is a general term for disease categories, including juvenile periodontitis (JP), rapidly progressive periodontitis (RPP), and adult periodontitis (AP), which may or may not share a common etiology and pathogenesis. These disease categories are characterized by differences in progression of tissue destruction and differences in age group susceptibility, but not, to our knowledge, by differences in cytokine responses of inflammatory cells. The present study examined blood cell counts and interindividual variation in the ability of PBMC of patients in three different categories of periodontitis to produce cytokines after stimulation with different oral bacterial species in vitro. The AP group had a significantly lower production of IL-1ra when stimulated with Porphyromonas gingivalis (P.g.) and Actinobacillus actinomycetemcomitans (A.a.) (P < 0.05). Streptococcus sanguis (S.s.), which is associated with normal periodontal conditions, induced extremely high levels of IL-1 alpha and TNF alpha production in all groups. The RPP group had a significantly higher number of monocytes (MC) than the AP group (P < 0.05). Additionally, JP patients had a significantly higher concentration of polymorphonuclear granulocytes compared to juvenile controls (P < 0.05). In conclusion, IL-1 alpha, TNF alpha, or IL-6 production by peripheral blood MC after in vitro stimulation with oral bacterial type stains may not distinguish different categories of periodontitis. The results support the hypothesis that the cytokine IL-1ra is produced in different concentrations in the two groups: RPP and AP. Furthermore, elevated MC concentration in the RPP group compared to the AP group may be an important pathogenic feature in RPP.

Humoral immune responses to Porphymmonas gingivalis and Actinobacillus actinomycetemcomitans in adult periodontitis and rapidly progressive periodontitis

The relationships between various forms of periodontal disease and the avidities of serum antibodies of all 3 immunoglobulin (Ig) classes (IgG, IgM and IgA) to Porphyromonas gingivalis and Actinobacillus actinomycetemcomitans were investigated. Twenty-four patients with untreated adult periodontitis and twelve untreated patients diagnosed as suffering from the early-onset form of periodontitis, rapidly progressive periodontitis, were studied. The latter group were matched for age and sex to healthy controls. Antibody titres were measured and avidity (expressed as molarity) was further assayed using the thiocyanate elution method. Avidity has previously been shown to relate to the biological function of antibody. IgM avidities to P. gingivalis were lower in the rapidly progressive periodontitis group than in the adult periodontitis group (0.54 M vs 0.74 M). IgG avidities tended to be lower in the former than in the latter group (0.58 M vs 0.92 M). In accordance with other workers, seropositivity was defined as an immunoglobulin titre more than twice the median level of control sera. Only 2 of the rapidly progressive periodontitis group were seropositive. Interestingly, the seronegative rapidly progressive periodontitis patients were significantly different (0.53 M vs 0.92 M). The data that patients with various forms of periodontal disease appear to produce antibodies of differing avidity to P. gingivalis suggest that the quality of the humoral immune response to suspected periodontopathogens may have a bearing on the aetiology of periodontal disease.

Inhibition of crevicular fluid neutrophil elastase by α1-antitrypsin in periodontal health and disease

Gingival crevicular fluid (GCF) was collected from two healthy, two gingivitis and two periodontitis sites of two groups of individuals presenting for treatment of chronic adult periodontitis (group 1, 25 subjects; group 2, seven subjects) and from distal approximal sites of two incisors and one molar of 10 subjects with periodontal health. GCF eluates of periodontitis group 1 and controls, prepared by a technique that lysed polymorphonuclear leucocytes (PMN) in the samples, were assayed for functional neutrophil elastase (NE) and immunoreactive α 1-antitrypsin ( α 1-AT) and α 1-antitrypsin-neutrophil elastase complex ( α 1-AT-NE). Periodontitis group 2 GCF eluates, generated by a method that did not disrupt PMNs, were assayed for functional NE in the presence and absence of a specific NE inhibitor. A greater amount of NE (ng/5-s sample) was found in eluates of GCF from diseased sites irrespective of whether or not the eluates contained products of lysed PMNs. However, the GCF eluates prepared without disrupting PMNs contained only about one-tenth as much NE as eluates of corresponding sites that included constituents of lysed PMNs. The amount of α-AT in GCF was insufficient to inactivate most of the NE available for release into the gingival sulcus at either healthy or diseased sites. In addition, much of the α 1-AT in GCF was not complexed with NE under conditions of excess NE. More than 90% of the NE in GCF from each site category was inactivated by the NE specific inhibitor. It is concluded, because of the large quantity of NE available in PMNs compared to the amount of NE inhibitors in GCF, that at least locally transient free NE occurs, which contributes to tissue destruction in chronic adult periodontitis.

Ex vivo studies of polymorphonuclear neutrophils from patients with early‐onset forms of periodontitis (I).

The polymorphonuclear neutrophil (PMN) appears to be an important cell in the protection of the host from pathogenic periodontal microorganisms and, despite some reports to the contrary, it is generally assumed that early-onset forms of periodontal disease (including both juvenile and rapidly progressing periodontitis) are associated with a defect in PMN chemotactic behaviour. The purpose of the present study was to examine the peripheral PMN chemotactic behaviour, using the under agarose method, in 4 groups, namely healthy periodontium group (n = 7), gingivitis group (n = 8), early-onset periodontitis group (n = 17) and adult periodontitis group (n = 8). PMN from early-onset periodontitis patients showed normal random and chemotactic locomotory behaviour when compared with those of PMN from subjects of the other groups. No statistically significant difference could be found among the 4 studied groups, with regard to spontaneous and oriented migration.

Infection by Porphyromonas gingivalis and Actinobacillus actinomycetemcomitans, and antibody responses at different ages in humans.

This study examined the serum IgG and IgM responses against Porphyromonas gingivalis and 3 serotypes of Actinobacillus actinomycetemcomitans, and the correlations of these responses with age and homologous infection. A total of 90 individuals were included in this study: 40 subjects with gingivitis, 40 periodontally healthy subjects, and 10 adult periodontitis subjects. The subjects in the gingivitis and periodontally healthy groups were divided into 4 stages based on their physiological age: early childhood, school age, puberty, and adult. In the gingivitis group, there was a positive correlation between increase in age and increase in serum IgG antibody levels against P. gingivalis until puberty. However, no statistically significant difference was found between the puberty stage and the adult stage. The average level of IgG antibodies against A. actinomycetemcomitans in the school age gingivitis group was significantly higher than that in the early childhood gingivitis group for all serotypes (p < 0.01). In serotype c, IgG antibody levels in the school age gingivitis group were significantly higher than in the early childhood gingivitis group or the adult gingivitis group (p < 0.01). With both P. gingivalis and A. actinomycetemcomitans, positive correlations between elevated IgG level and infections by these microorganisms were found in the puberty gingivitis and adult periodontitis groups.

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.

Myeloperoxidase activity in peripheral blood, neutrophil crevicular fluid and whole saliva of patients with periodontal disease.

Mean levels of myeloperoxidase (MPO) activity were determined in samples of gingival crevicular fluid (GCF), whole saliva and peripheral blood neutrophils from patients with rapidly progressive periodontitis (RPP) and adult periodontitis (AP) using a spectrophotometric method. The mean neutrophil MPO activity in the RPP group was 563.1 +/- 137.05 U/l x 10(6)/ml, that in the AP group was 483.3 +/- 88.81 U/l x 10(6)/ml, and that in the control group was 220.6 +/- 26.7 U/l x 10(6)/ml. The mean GCF MPO activity in the RPP group was 15.13 +/- 2.34 U/mg, which was significantly higher than in the other two groups. The mean whole saliva MPO activity in the RPP group was 0.14 +/- 0.04 U/ml, that in the AP group was 0.11 +/- 0.02 U/ml, and that in the control group was 0.05 +/- 0.06 U/ml. MPO activity detected in the samples was significantly increased in the patient groups when compared to the healthy subjects. The highest MPO activity was found in the RPP group. The present findings suggest a relationship between MPO activity and the pattern and severity of periodontal breakdown. Also the increased MPO activity in periodontally diseased patients can be attributed to the increased number of neutrophils, the degranulation of these cells and also their hyperactive state in the presence of chronic antigenic stimulation.

Serum antibody responses in human periodontitis to cellular components of Capnocytophaga

Serum levels of IgM, IgG and IgG-antibody subclasses directed against cell envelopes, lipopolysaccharides and cytoplasmic fractions from Capnocytophaga sputigena, C. gingivalis and C. ochracea were examined in age-, race- and sex-matched periodontally healthy ( n = 25) subjects and subjects with adult periodontitis ( n = 25). The envelopes and cytoplasmic fractions were obtained by ballistic disintegration of the cells and ultracentrifugation. Cell envelopes were treated with DNase, RNase and lysozyme. Lipopolysaccharides were obtained by hot phenol-water extraction and treated with DNase and RNase. The relative levels of the antibodies in response to the cell fractions were measured by the streptavidinbiotin micro enzyme-linked immunosorbent assay. Both groups showed IgM and IgG antibodies to each fraction of the three Capnocytophaga species, but the frequency of positive IgG subclass responses varied. The IgG4 responses were lower than the other subclasses. There were no significant differences between the IgM antibody levels of the two groups. However, the adult periodontitis group had significantly lower IgG antibody titres to the cell envelopes and cytoplasmic fractions of C. gingivalis and C. ochracea, and lipopolysaccharide of C. gingivalis. These results were reflected in the depressed levels of IgG1 and/or IgG2 to these cellular fractions from the same bacterial species. The adult periodontitis group also showed a lower level of IgG1 to the cytoplasmic fractions of C. sputigena without any depression in the total IgG antibody level. There were no significant differences between the groups in IgG3 and IgG4 antibody levels to any of the cellular fractions. These findings suggest that some individuals are unable to mount certain IgG subclass responses to Capnocytophaga, perhaps increasing their susceptibility to periodontitis, and or may indicate the presence of a smaller population of Capnocytophaga at the diseased sites.