Periodontal Pockets Of Patients Research Articles

Yeast diversity in the oral microbiota of subjects with periodontitis:Candida albicansandCandida dubliniensiscolonize the periodontal pockets

The term periodontitis encompasses several polymicrobial infectious diseases, of multifactorial etiology, with chronic and aggressive forms. In spite of the etiopathogenic differences between these two forms of the disease, few studies have analyzed the subgingival colonization by yeast. The objective of this investigation was to analyze the composition of the yeast microbiota present in the mucosa and subgingival sites of healthy individuals and patients with aggressive and chronic periodontitis. For this, samples were recovered from these two locations and the yeast recovered identified by phenotypic and genotypic methods. Patients with chronic periodontitis showed significant differences in relation to the other groups with respect to carrier status (69.2% versus 35.7% of healthy individuals; [chi(i)(2) test; p=0.014]), the total number of isolated colony forming units or CFU (mean and ranges 281.6 (0-6048) [K-W(2)=6.998; p=0.03]), the Simpson diversity index (I) in site b (I(b)=0.344 versus healthy subjet and aggresive periodontitis where I=0 [multiple t-test comparisons with the Bonferronni correction, p<0.05]), and the species profile. Interestingly, in spite of the varied profiles of the species present in the mucosa of the three groups analyzed we noted that only C. albicans and C. dubliniensis were capable of colonizing the periodontal pockets in patients with chronic periodontitis, while only C. albicans was identified in the subgingiva of healthy individuals and patients with aggressive periodontitis.

EBV-1 and HCMV in aggressive periodontitis in Brazilian patients

The purpose of the present investigation was to compare the presence of Epstein-Barr virus type 1 (EBV-1) and of Human Cytomegalovirus (HCMV) in crevicular fluid samples from deep and shallow periodontal pocket sites of Brazilian patients with aggressive periodontitis. A total of 30 systemically healthy patients with aggressive periodontitis participated in the study. Paper points were inserted into 2 gingivitis sites (<3 mm) and into 2 periodontitis sites (>5 mm) in each patient. PCR assay was used to identify genomic copies of HCMV and EBV-1. Twenty-three patients (77%) were positive for EBV-1, while only 2 patients (6%) were positive for HCMV. The McNemar test revealed a positive association between EBV-1 and periodontal lesions (p=0.043). Thirty-four (57%) out of 60 periodontitis sites were positive for EBV-1, whereas 18 (30%) gingivitis sites were positive (p=0.01). Only two sites (6.7%) were positive for HCMV. No positive association was found between HCMV and periodontitis or gingivitis (p=0.479). The elevated occurrence of EBV-1 DNA in periodontal pockets of patients with aggressive periodontitis supports a possible periodontopathic role of this virus.

In vitro minocycline activity on superinfecting microorganisms isolated from chronic periodontitis patients

Chronic periodontitis is the most common type of periodontitis and it is associated with various species of microorganisms. Enteric rods, Pseudomonas, Staphyloccocus and Candida have been retrieved from periodontal pockets of patients with chronic periodontitis and correlated to cases of superinfection. Local or systemic antibiotic therapy is indicated to reinforce the effects of the conventional mechanical therapy. Minocycline has been suggested as one of the most effective drugs against periodontal pathogens. The aim of this work was to evaluate the minimal inhibitory concentration (MIC) of minocycline on superinfecting microorganisms isolated from the periodontal pocket and the oral cavity of individuals with chronic periodontitis. Isolates of Enterobacteriaceae (n = 25), Staphylococcus spp. (n = 25), Pseudomonas aeruginosa (n = 9) and Candida spp. (n = 25) were included in the study. Minimal inhibitory concentrations (MIC) of minocycline were determined using the Müeller-Hinton agar dilution method. Staphylococcus spp. isolates were the most sensitive to minocycline with a MIC of 8 microg/mL, followed by Enterobacteriaceae with a MIC of 16 microg/mL. The concentration of 16 microg/mL inhibited 96% of Candida spp. isolates. The MIC for 88.8% of the isolates of Pseudomonas aeruginosa was 128 microg/mL. A concentration of 1,000 microg/mL was not enough to inhibit 100% of the tested isolates.

Metronidazole concentrations in plasma, saliva and periodontal pockets in patients with periodontitis

Metronidazole is widely used antibacterial compound in the treatment of some types of periodontal disease. Pharmacokinetics of metronidazole in plasma has been well-described but few data exist about penetration of the drug to the gingival crevice fluid. The aim of the present study was to compare the concentrations of metronidazole in plasma, saliva and gingival crevice fluid in patients with periodontitis after multiple administration. Eleven patients with severe generalised adult periodontitis participated in the study. Metronidazole, 500 mg, was administered orally two or three times per day for at least 2 days before sample collection. Samples were collected 2 h after last dose. Metronidazole concentrations in all fluids were measured with high-performance liquid chromatography. Mean drug concentrations in plasma, saliva and crevice fluid were 14.33, 15.15 and 12.86 microg/ml, respectively. Difference between plasma and crevice fluid or between plasma and saliva did not reach statistical significance. Present study revealed that metronidazole penetrates well into gingival crevice fluid and saliva. Metronidazole concentrations in crevice fluid are about equal to the protein unbound drug concentrations in plasma. Therefore, general pharmacokinetic data of metronidazole can be also applied in the treatment of periodontal disease and in the design of respective treatment regimens.

Staphylococcus spp. in the oral cavity and periodontal pockets of chronic periodontitis patients

Staphylococcus spp are not usually isolated from the oral cavity, and when this occurs, they are considered to belong to the transitory microbiota. Individuals with periodontal disease represent possible reservoirs of these opportunistic bacteria in the oral cavity. The use of antibiotics for treatment of periodontal disease or other infections may predispose to the increase of the number of Staphylococcus spp. in the oral cavity. These microorganisms easily become resistant to antibiotics, and may result in superinfection. The purpose of this study was to evaluate the presence of Staphylococcus spp. in the oral cavity and in periodontal pockets of patients with chronic periodontitis, identify the isolates and verify the relationship between the presence of Staphylococcus spp. in the oral cavity and presence of periodontal pockets. The study included eighty-eight patients, 25-60 years of age, with chronic periodontitis, and at least two sites with probing depth > 5 mm. Individual data examination was assessed. Then, samples were colleted from the periodontal pocket with the aid of paper tips and from the oral cavity through mouth rinses. Out of the total of patients, 37.50% presented Staphylococcus spp. in the periodontal pocket and 61.36% in the oral cavity, 27.27% presented the bacteria in both sites. S. epidermidis was the most prevalent specie in the periodontal pocket (15.9%) and oral cavity (27.27%). The occurrence of higher proportions of nonresident's microorganisms in subgingival samples and oral sites may represent significant problem in causing and maintaining periodontal infections.

Oral Distribution of Genera, Species and Biotypes of Yeasts in Patients with Marginal Periodontitis

Yeasts can be members of the commensal flora in the healthy human mouth. They have also been found in periodontal pockets of patients with marginal periodontitis, but little is known about their distribution in other oral sites of such patients. The aim of the present study was to examine the distribution of genera, species and biotypes of yeasts in various sites of oral cavities of patients with chronic marginal periodontitis. Samples were taken from the periodontal pockets, buccal mucosa and palate of 70 marginal periodontitis patients and 45 healthy individuals. After cultivation yeast colonies were selected according to morphology and the biotype was determined by a commercial kit (ID 32C, bioMe´rieux, France). Oral yeasts were detected in 34.3% of the marginal periodontitis patients and 42.2% of the healthy subjects. Among the sites examined, the buccal mucosa was the major site for yeasts, being colonized in 31.4% of the marginal periodontitis patients and in 35.6% of the healthy subjects. Two genera (Candida and Saccharomyces ), four species ( C. albicans, C. dubliniensis, C. parapsilosis and S. cerevisiae ) and 19 biotypes were identified from the marginal periodontitis patients, while one genus ( Candida ), two species ( C. albicans and C. dubliniensis ) and 11 biotypes were obtained from the healthy subjects. C. albicans was the most dominant species in all the oral sites. Among the other Candida species, C. dubliniensis dominated, being most prominent in the periodontal pockets. Two biotypes (7146340015 and 7347340015) of C. albicans and one biotype (7142100015) of C. dubliniensis were predominant in the marginal periodontitis patients, whereas three biotypes (7146340015, 7147340015 and 7347340015) of C. albicans dominated in the healthy subjects. The differences in the distribution of yeast species and biotypes may suggest cell, tissue or site tropism in oral yeast colonization. Key words : yeasts , biotypes, periodontitis.

Porphyromonas gingivalis lipopolysaccharide signaling in gingival fibroblasts-CD14 and Toll-like receptors.

Periodontal disease is the major cause of adult tooth loss and is commonly characterized by a chronic inflammation caused by infection of oral bacteria. Porphyromonas gingivalis (P. gingivalis) is one of the suspected periodontopathic bacteria and is frequently isolated from the periodontal pockets of patients with chronic periodontal disease. The lipopolysaccharide (LPS) of P. gingivalis is a key factor in the development of periodontitis. Gingival fibroblasts, which are the major constituents of gingival connective tissue, may directly interact with bacteria and bacterial products, including LPS, in periodontitis lesions. It is suggested that gingival fibroblasts play an important role in the host responses to LPS in periodontal disease. P. gingivalis LPS enhances the production of inflammatory cytokines such as interleukin (IL)-1, IL-6, IL-8, and tumor necrosis factor alpha (TNF-alpha) in gingival fibroblasts. However, the receptor that binds with P. gingivalis LPS on gingival fibroblasts remained unknown for many years. Recently, it was demonstrated that P. gingivalis LPS binds to gingival fibroblasts. It was also found that gingival fibroblasts express CD14, Toll-like receptor 4 (TLR4), and myeloid differentiation primary response gene 88 (MyD88). P. gingivalis LPS treatment of gingival fibroblasts activates several intracellular proteins, including protein tyrosine kinases, and up-regulates the expression of monocyte chemoattractant protein-1 (MCP-1), extracellular signal-regulated kinase 1 (ERK1), and signal-regulated kinase 2 (ERK2), IL-1 receptor-associated kinase (IRAK), nuclear factor-kappaB (NF-kappaB), and activating protein-1 (AP-1). These results suggest that the binding of P. gingivalis LPS to CD14 and TLR4 on gingival fibroblasts activates various second-messenger systems. In this article, we review recent findings on the signaling pathways induced by the binding of P. gingivalis LPS to CD14 and Toll-like receptors (TLRs) in gingival fibroblasts.

Effect of Anti-CD14 Antibody on Experimental Periodontitis Induced by Porphyromonas gingivalis Lipopolysaccharide

The lipopolysaccharide (LPS) released by Porphyromonas gingivalis, a Gram-negative bacterium found in the periodontal pockets of patients with periodontitis, induces bone resorbing activity in vivo. We previously showed that a receptor for LPS on human gingival fibroblasts and gingival epithelial cells is CD14. In this study, we established a mouse model of experimental periodontitis by applying a P. gingivalis LPS solution to the buccal region of mice. P. gingivalis LPS-induced bone resorption and inter-leukin-6 production in the gingival tissues were significantly inhibited by pretreatment with anti-CD14 antibody for 5 weeks prior to LPS treatment. This result suggests that anti-CD14 antibody may be usable as a prototype for the development of drugs for the treatment of periodontal disease.

Ethyl Cellulose and Polyethylene Glycol-Based Sustained-Release Sparfloxacin Chip: An Alternative Therapy for Advanced Periodontitis

ABSTRACTThis study reports the development of a sustained-release system of sparfloxacin for use in the treatment of periodontal disease. A sustained-release sparfloxacin device was formulated, based on ethyl cellulose (EC) 10 cps, polyethylene glycol (PEG) 4000, and diethyl phthalate (DEPh). It will hereafter be called the sparfloxacin chip (SRS chip). The chip has dimensions of 10 mm length, 2 mm width, and 0.5 mm thickness. The in vitro drug release pattern and clinical evaluation of the formulations were studied. Reports of the short-term clinical study show that the use of the SRS chip may cause complete eradication of the pathogenic bacteria in the periodontal pockets of patients who have chronic generalized periodontitis. In this clinical study, the baseline and follow-up measurements of various clinical indices, such as oral hygiene index(es), plaque index, sulcular depth component of periodontal disease index, gingival crevicular fluid flow measurement, and dark field microscopic examinations of oral pathogens in plaque samples were studied. Significant improvements were observed in many parameters of the treatment group compared with the placebo group.

A influência do sexo e da idade na prevalência de bolsas periodontais

Este trabalho teve como objetivo avaliar a influência dos fatores de risco na prevalência de bolsas periodontais em pacientes atendidos na clínica do terceiro e quarto anos da Faculdade de Odontologia de Piracicaba - Unicamp. Foram avaliados 100 pacientes através do levantamento dos dados contidos nas fichas clínico-anamnésicas, sendo consideradas bolsas de profundidade: 3 mm, 5 mm, 7 mm e 10 mm, de acordo com o sistema diagnóstico WS (SALLUM; SALLUM27, 1996). Os resultados foram comparados entre as profundidades de sondagem e as variáveis idade, sexo, bem como sua distribuição por sextantes. Observou-se maior prevalência de bolsas periodontais no sexo masculino, bem como maior profundidade de sondagem em pacientes acima de 31 anos. A distribuição de bolsas periodontais entre os sextantes foi homogênea.

Proteolysis and utilization of albumin by enrichment cultures of subgingival microbiota.

Subgingival dental plaque consists mainly of microorganisms that derive their energy from amino acid fermentation. Their nutrient requirements are met by the subgingival proteolytic system, which includes proteases from microorganism and inflammatory cells, and substrate proteins from sulcus exudate, including albumin. To determine the selective effect of individual proteins on microbiota, we used albumin as the main substrate for growth. Eight subgingval plaque samples from untreated periodontal pockets of patients with adult periodontitis were inoculated in peptone yeast medium with bovine albumin (9 g/l). After three subculture steps, cell yields of the enrichment cultures at the medium with 0, 1.25, 2.5, 5, 10, and 20 g/l albumin were determined. Proteolytic activity (U/absorbance at 550 nm) of the enrichment cultures and different isolates derived from the cultures was estimated by the degradation of resorufin-labeled casein. It was observed that the yield of the mixed culture was albumin limited, and the proteolytic activities of the cultures in albumin broth were higher than in control (peptone broth). Among the isolates from the enrichment cultures, Peptostreptococcus micros, Prevotella melaninogenica, Prevotella buccae and Prevotella bivia demonstrated proteolysis. The frequent occurrence of Streptococcus gordonii and Streptococcus anginosus in the albumin cultures is explained by their ability to utilize arginine as an energy source for growth. Albumin in the medium was partly degraded by pure cultures but completely consumed in enrichment cultures, indicating synergy of bacterial proteinases. It is concluded that the subgingival microbiota possesses proteolytic activity and may use albumin as a substrate for their growth. Enrichment cultures on albumin may serve as a relatively simple in vitro model to evaluate the effects of proteinase inhibitors.

"Checkerboard" DNA-probe analysis and anaerobic culture of initial periodontal lesions.

In this study, we compared a new, rapid DNA-probe assay with anaerobic culture for characterizing the microbiology of initial periodontal lesions in adults. We used the microbiological data from both assays to identify the microbiota associated with the conversion from gingival health to periodontal disease. In previous studies of the microbiota of periodontal infections, investigators have mainly examined the microbiota of periodontal pockets in patients with established disease and have used anaerobic cultural methods. Little information is available about the microbiota associated with the initiation of periodontitis [1]. An understanding of the initial stages of periodontal disease (i.e., when loss of attachment first occurs around a previously healthy tooth) will be important for risk assessment and prevention of these infections. By using cultural methods, in which the predominant species are isolated in pure culture and identified by phenotypic tests, all isolates can be characterized, but these methods are labor intensive and time-consuming and therefore limit the number of samples that can be analyzed. To facilitate large-scale clinical studies, which are necessary to assess microbiological risk markers and risk factors for periodontal disease, more-rapid methods for assaying multiple bacterial species in plaque samples will be required. We assessed one such method, the checkerboard DNA-probe assay [2], which enables simultaneous analysis of 28 plaque samples with - 1.5-mm increase in periodontal attachment loss during monitoring. Subgingival plaque from active and inactive sites was sampled for anaerobic culture. Fifty isolates from each sample were cultured and identified on the basis of gram staining, growth in air, fluorogenic substrate tests [3], and SDS-PAGE of whole cell proteins [4]. The cultural data were expressed as the percentage of total cultivable microbiota represented by each species identified in each sample. We calculated the absolute level (count of cfu per

Tetracycline‐resistant micro‐organisms recovered from patients with refractory periodontal disease

Tetracycline in combination with scaling and root planing is frequently used to treat refractory periodontal disease. This study examined tetracycline resistance in bacteria recovered from periodontal pockets of patients with refractory periodontitis. Bacterial isolates resistant to 10 micrograms/ml of tetracycline were isolated from plaque samples of 17 patients, of whom 6 had received tetracycline within 8 weeks prior to sampling. Minimal inhibitory concentrations (MICs) of tetracycline and minocycline were determined by agar dilution. In the 6 patients who had received tetracycline, a mean of 22.9% (+/- 38.2) of the total cultivable subgingival flora were resistant to tetracycline, compared with a mean of 7.2% (+/- 8.5) in the untreated group. Although various organisms were isolated, in most patients, the tetracycline-resistant organisms were dominated by Streptococcus spp. Overgrowth of Candida was found in one patient, and of Enterobacteriaceae in another patient, while small numbers of yeast or Staphylococcus spp. were isolated from the plaque samples of 9 others. 3 out of 4 patients who did not respond to tetracycline treatment had a variety of tetracycline-resistant anaerobic Gram-negative rods present. No correlation was found between increased proportions of tetracycline resistance in the whole bacterial sample and the presence of resistant periodontal pathogens.

The effect of a redox agent, methylene blue, on the survival ofPorphyromonas gingivalis in vitro

Methylene blue, at a concentration of 1.0 mg/ml, was able to raise the redox potential (Eh) of pre-reduced culture medium from −288 mV to −154 mV and to poise the medium at an Eh of −171 mV during 48-h incubation in an anaerobic atmosphere. Addition of the dye to suspensions of the anaerobic periodontopathogen,Porphyromonas gingivalis, to give a final concentration of 1.0 mg/ml raised their Eh to −125 mV. During a 24-h period of anaerobic incubation, the dye maintained the Eh at a level (−150 mV) that was more than 200 mV higher than control, dye-free suspensions, and this was accompanied by at least a 6-log reduction in the viable count. The bactericidal effect of the methylene blue could be counteracted by the reducing agent dithiothreitol at a concentration of 2.0 mg/ml, which lowered the Eh to a level (−333 mV) similar to that of controls. These results have demonstrated that the presence of 1.0 mg/ml methylene blue, in its oxidized form, in an environment is inimical to the survival ofP. gingivalis and that this is related, directly or indirectly, to its ability to raise the Eh of the environment. Topical application of methylene blue, or other redox agents, may be an effective means of eliminating this organism from the periodontal pockets of patients with chronic periodontitis.

Relationship of collagenase and cathepsin G activity in gingival crevicular fluid.

Human neutrophil cathepsin G has been identified as a potent proteolytic activator of latent human neutrophil collagenase in vitro. In order to examine the role of cathepsin G in the activation mechanism of latent human neutrophil collagenase in vivo, gingival crevicular fluid was collected from periodontal pockets of patients with adult periodontitis and the relationship of cathepsin G to the proportion of endogenously active collagenase and total collagenase activity was determined. The changes in these parameters were monitored before and after periodontal therapy and compared to control values obtained for periodontal sites without clinical signs of inflammation or increased pocket depth. A significant decrease in cathepsin G and collagenase activity in gingival crevicular fluid collected from initially deep periodontal pockets was observed in response to scaling and root planing (P less than 0.025, Wilcoxon signed rank test). Also the proportion of endogenously active collagenase decreased (P less than 0.05). There was a significant correlation of cathepsin G and total collagenase activity. However, no correlation of cathepsin G activity and endogenously active collagenase was observed. The results indicate the existence of several distinct activation pathways for latent human neutrophil collagenase in vivo and suggest that, apart from cathepsin G, other proteolytic activation cascades and/or non-proteolytic activation pathways participate in the activation of latent human neutrophil collagenase in vivo.

A sensitive enzymatic method (SK-013) for detection and quantification of specific periodontopathogens.

Porphyromonas gingivalis, Bacteroides forsythus, and Treponema denticola have been found to predominate in periodontal pockets of patients with adult periodontitis. These microorganisms hydrolyze the synthetic peptide N-benzoyl-DL-arginine-2-naphthylamide (BANA). In this study, we developed an enzymatic method, designated SK-013, to detect the existence of these microorganisms in subgingival plaque bacteria. This enzymatic method was based on the observation of the hydrolysis of N-carbobenzoxy-glycyl-glycyl-arginyl-3,5-dibromo-4-hydroxyaniline (N-CBz-Gly-Gly-Arg-DBHA) and made more sensitive by adding an enhancing system. The SK-013 was specifically positive for P. gingivalis, B. forsythus, T. denticola, and some strains of Capnocytophaga species, but was not specific for any of the other bacterial strains tested. This SK-013 system may be valuable for detection and quantification of periodontal disease-associated bacteria in subgingival plaque and thus for diagnosis of periodontal infections.

Predominant obligate anaerobes in human periodontal pockets.

This study was carried out to investigate the predominant anaerobic bacteria of periodontal pockets in patients with advanced periodontitis, who had no previous treatment other than supragingival scaling, no history of recent or chronic systemic illness, nor any intake of antibiotics within 6 weeks prior to bacteriological sampling. Care was taken not to ignore tiny-colony-forming anaerobes, by means of a stereoscope and an anaerobic glove box system. Out of 422 (100%) isolates, 380 (90%) were obligate anaerobes, suggesting that the environment in periodontal pockets was anaerobic and favors the growth of obligate anaerobes. Among the 380 obligate anaerobes isolated, strains belonging to Eubacterium (54%) were predominant, and many of them occurred in tiny colonies. The other obligate anaerobes isolated were assigned to Wolinella (9%), unidentified motile rods which resemble Wolinella (7%), Peptostreptococcus (6%), Fusobacterium (5%), Bacteroides (2%; including those reclassified to Prevotella and Porphyromonas) and Selenomonas (0.5%). Among the isolates, 67% were Gram-positive bacteria, including 59% of rods (mostly asaccharolytic Eubacterium), suggesting that these bacteria, particularly strains of the Eubacterium species, may play an important role in etiology of adult periodontitis.

Evaluation of acrylic strips containing amoxycillin with clavulanic acid for local drug delivery

The in vitro release of amoxycillin with clavulanic acid from acrylic strips at initial concentrations of 30,40 and 50 per cent w/w was monitored using a double-beam ultraviolet spectrophotometer and compared with release of tetracycline hydrochloride. Highest levels of the antibacterial agents were released during the first 24 h period. Therapeutic levels of the drugs continued to be released during the subsequent 9 day period and were shown to be biologically active. Furthermore, for amoxycillin with clavulanic acid, an initial concentration of 40 per cent gave the highest level of release on day 10; while, for tetracycline, 50 per cent provided the highest level of release. Local application of 40 per cent amoxycillin with clavulanic acid incorporated into acrylic strips placed in periodontal pockets in patients with established periodontitis produced a marked change in the subgingival microflora as monitored by dark-field microscopy and cultural techniques. These changes in the subgingival flora were concomitant with elimination of bleeding on probing at the treated sites and were still evident 3 weeks after removal of the acrylic strips. The sensitivity of Bacteroides gingivalis (syn. Porphyromonas gingivalis) and Bacteroides intermedius (syn. Prevotella intermedia) isolated before and after treatment to amoxycillin with clavulanic acid remained unchanged.

歯周病原菌の酵素活性を指標とした迅速診断法（ＳＫ‐０１３） 酵素活性と臨床所見，ポケット内細菌との関係

There have been various laboratory methods for the microbiological diagnosis of periodontal disease. However, there have been some disadvantages in these methods. In this study of the application of a chair-side test for microbiological diagnosis, the activity of peptidases in periodontal pockets of patients was examined by using the assay system SK-013. SK-013 consists of synthetic substrates and is capable of rapidly (in 15 min) evaluating the activity of specific peptidase from Treponema denticola and Bacteroides species. Using SK-013, we evaluate the correlation between the enzymatic activity, clinical periodontal parameters and subgingival level of microorganisms, including phase contrast microscopy. We calculated the sensitivity and efficacy of SK-013 as a diagnostic indicator in the presence of Spirochetes and in periodontitis. A positive correlation were demonstrated between enzymatic activity, clinical periodontal parameters, the numbers of total cell count, Spirochetes, and M & S ratio. SK-013 was highly sensitive and efficacious (sensitivity: 92%, efficacy: 96%). We concluded that the assay system SK-013 is a useful chair-side method for diagnosing periodontal disease.

Scanning electron microscopic examination of pocket wall epithelium and associated plaque in localized juvenile periodontitis.

The purpose of this investigation was to describe the morphologic characteristics of epithelial-associated plaque in periodontal pockets of patients with localized juvenile periodontitis (LJP). 25 tissue specimens obtained from 10 adolescent patients were examined by scanning electron microscopy. Specimens were evaluated to determine the following specific features: (1) distribution of microbial colonies on the epithelial surface; (2) topographic features of pocket epithelium associated with microbial colonies; and (3) the predominante microbial morphologic types comprising the colonies. Observations made during this investigation revealed the following. (1) The surface epithelium in the coronal one-third of the pocket wall was essentially healthy in appearance and exhibited no distinct microbial colonies or unusual topographic features. (2) The surface epithelium in the middle one-third area featured randomly-dispersed microbial colonies consisting of 3 major morphotypes: cocci, bacilli and coccobacilli. Also in this zone, there was morphologic evidence of microbial penetration of the epithelial barrier along intercellular spaces. (4) The apical one-third zone was characterized by lymphocytic infiltration, epithelial cavitation and ulcerations, and singular organisms entrapped in fibrin meshworks. There were no distinct microbial colonies in this zone, although individual spirochetes, fusiforms, filamentous organisms, and short and long rods were observed.