Trypsin-like activity in subgingival plaque. A diagnostic marker for spirochetes and periodontal disease?

Evaluation of the ability of the trypsin-like peptidase activity assay to detect severe periodontitis

Objectives

N-benzoyl-DL-arginine peptidase (trypsin-like peptidase) is specifically produced by certain strains of periodontitis-associated bacteria. We aimed to examine the effectiveness of an objectively quantified trypsin-like peptidase activity assay (TLP-AA) for detecting severe periodontitis.

Methods

The study population included 347 adults (108 men and 239 women; average age, 43.3 years) who underwent a full-mouth periodontal examination. Specimens for the TLP-AA were obtained using tongue swabs. Using a color reader, the TLP-AA results were obtained as a* values, with higher positive a* values indicating an increased intense enzymatic activity. The predictive validity of the TLP-AA results for severe periodontitis was assessed using receiver operating characteristic curve analysis and the periodontitis case definition provided by the Centers for Disease Control and Prevention/American Academy of Periodontology as the gold standard. Furthermore, multivariable logistic regression analyses were performed to predict severe periodontitis using the TLP-AA results and health characteristics, as the exposure variables.

Results

Severe periodontitis was observed in 5.2% of the participants. TLP-AA had high diagnostic accuracy for severe periodontitis, with an area under the curve of 0.83 (95% confidence interval [CI]: 0.75–0.92). The cut-off score for the a* value that best differentiated individuals with severe periodontitis was 0.09, with a sensitivity of 83% and specificity of 77%. Multivariable logistic regression analyses revealed that the TLP-AA results were significantly associated with severe periodontitis after adjusting for health characteristics (adjusted odds ratios: 1.90 [95% CI: 1.37–2.62] for the a* value).

Conclusions

Objectively quantified TLP-AA results are potentially useful for detecting severe periodontitis in epidemiological surveillance.

Robotic gastrointestinal surgery: learning curve, educational programs and outcomes

The use of the robotic platform for gastrointestinal surgery was introduced nearly 20 years ago. However, significant growth and advancement has occurred primarily in the last decade. This is due to several advantages over traditional laparoscopic surgery allowing for more complex dissections and reconstructions. Several randomized controlled trials and retrospective reviews have demonstrated equivalent oncologic outcomes compared to open surgery with improved short-term outcomes. Unfortunately, there are currently no universally accepted or implemented training programs for robotic surgery and robotic surgery experience varies greatly. Additionally, several limitations to the robotic platform exist resulting in a distinct learning curve associated with various procedures. Therefore, implementation of robotic surgery requires a multidisciplinary team approach with commitment and investment from clinical faculty, operating room staff and hospital administrators. Additionally, there is a need for wider distribution of educational modules to train more surgeons and reduce the associated learning curve. This article will focus on the implementation of the robotic platform for surgery of the pancreas, stomach, liver, colon and rectum with an emphasis on the associated learning curve, educational platforms to develop proficiency and perioperative outcomes.

Washing- and Separation-Free Electrochemical Detection of Porphyromonas gingivalis in Saliva for Initial Diagnosis of Periodontitis

Indirect detection of Porphyromonas gingivalis in saliva, based on proteolytic cleavage by an Arg-specific gingipain (Arg-gingipain), has traditionally been used for simple, initial diagnosis of periodontitis. To accurately detect P. gingivalis using a point-of-care format, development of a simple biosensor that can measure the exact concentration of P. gingivalis is required. However, electrochemical detection in saliva is challenging due to the presence of various interfering electroactive species in different concentrations. Here, we report a washing- and separation-free electrochemical biosensor for sensitive detection of P. gingivalis in saliva. Glycine-proline-arginine conjugated with 4-aminophenol (AP) was used as an electrochemical substrate for a trypsin-like Arg-gingipain, and glycylglycine was used to increase the Arg-gingipain activity. The electrochemical signal of AP was increased using electrochemical-chemical (EC) redox cycling involving an electrode, AP, and tris(2-carboxyethyl)phosphine, and the electrochemical charge signal was corrected using the initial charge obtained before a 15 min incubation period. The EC redox cycling combined with the matrix-corrected signal facilitated a high and reproducible signal without requiring washing and separation steps. The proteolytic cleavage of the electrochemical substrate was specific to P. gingivalis. The calculated detection limit for P. gingivalis in artificial saliva was 5 × 10⁵ colony-forming units/mL, and the concentration of P. gingivalis in human saliva could be measured. The developed biosensor can be used as an initial diagnosis method to distinguish between healthy people and patients with periodontal diseases.

Current status of robotic gastrectomy for gastric cancer: comparison with laparoscopic gastrectomy

Robotic systems were developed to overcome limitations of laparoscopic surgery with its mechanical advantages. Along with the technical advances, robotic gastrectomy for gastric cancer is increasing. However, the evidence regarding safety and efficacy for robotic gastrectomy for gastric cancer is not mature yet. Although studies are limited, it is evident that robotic gastrectomy has a longer operation and less blood loss compared with laparoscopic gastrectomy. Studies revealed long-term oncological outcomes after robotic gastrectomy was comparable to those after laparoscopic gastrectomy. Taken together, robotic gastrectomy with systemic lymph node dissection is suggested as a safe procedure with equivalent short- and long-term oncologic outcomes to either laparoscopic or open gastrectomy for the surgical treatment of gastric cancer. However, high cost is the most significant barrier to justify robotic surgery as a routine and standard treatment for patients with gastric cancer. In the meanwhile, robotic surgery will be expansively used as long as technologic developments continue.

A Preliminary Study on the Ability of the Trypsin-Like Peptidase Activity Assay Kit to Detect Periodontitis

This study aimed to explore whether the Trypsin-Like Peptidase Activity Assay Kit (TLP-AA-Kit), which measures the activity of N-benzoyl-dl-arginine peptidase (trypsin-like peptidase), can be used as a reliable tool for periodontitis detection in population-based surveillance. In total, 105 individuals underwent a full-mouth periodontal examination and provided tongue swabs as specimens for further analyses. The results of the TLP-AA-Kit were scored between 1 and 5; higher scores indicated higher trypsin concentrations. Receiver operating characteristic analyses were used to evaluate the predictive validity of the TLP-AA-Kit, where the periodontitis case definition provided by the Centers for Disease Control/American Academy of Periodontology served as the reference. Severe and moderate periodontitis were identified in 4.8% and 16.2% of the study population, respectively. The TLP-AA-Kit showed high diagnostic accuracy for severe periodontitis, with an area under the curve of 0.93 (95% confidence interval = 0.88-0.99). However, the diagnostic accuracy of the TLP-AA-Kit for moderate/severe periodontitis was not reliable. While further studies are necessary to validate our results, the results provided herein highlight the potential of the TLP-AA-Kit as a useful tool for the detection of periodontitis, particularly in severe cases, for population-based surveillance.

Resistance to β-lactams and distribution of β-lactam resistance genes in subgingival microbiota from Spanish patients with periodontitis

OBJECTIVES

The aim of this study was to analyze the distribution of β-lactamase genes and the multidrug resistance profiles in β-lactam-resistant subgingival bacteria from patients with periodontitis.

MATERIALS AND METHODS

Subgingival samples were obtained from 130 Spanish patients with generalized periodontitis stage III or IV. Samples were grown on agar plates with amoxicillin or cefotaxime and incubated in anaerobic and microaerophilic conditions. Isolates were identified to the species level by the sequencing of their 16S rRNA gene. A screening for the following β-lactamase genes was performed by the polymerase chain reaction (PCR) technique: bla_TEM, bla_SHV, bla_CTX-M, bla_CfxA, bla_CepA, bla_CblA, and bla_ampC. Additionally, multidrug resistance to tetracycline, chloramphenicol, streptomycin, erythromycin, and kanamycin was assessed, growing the isolates on agar plates with breakpoint concentrations of each antimicrobial.

RESULTS

β-lactam-resistant isolates were found in 83% of the patients. Seven hundred and thirty-seven isolates from 35 different genera were obtained, with Prevotella and Streptococcus being the most identified genera. bla_CfxA was the gene most detected, being observed in 24.8% of the isolates, followed by bla_TEM (12.9%). Most of the isolates (81.3%) were multidrug-resistant.

CONCLUSIONS

This study shows that β-lactam resistance is widespread among Spanish patients with periodontitis. Furthermore, it suggests that the subgingival commensal microbiota might be a reservoir of multidrug resistance and β-lactamase genes.

CLINICAL RELEVANCE

Most of the samples yielded β-lactam-resistant isolates, and 4 different groups of bla genes were detected among the isolates. Most of the isolates were also multidrug-resistant. The results show that, although β-lactams may still be effective, their future might be hindered by the presence of β-lactam-resistant bacteria and the presence of transferable bla genes.

Point of Care- A Novel Approach to Periodontal Diagnosis-A Review

Periodontal disease, one of the prevalent oral diseases, is characterized by gingival inflammation and periodontal tissue destruction. Diagnosing this disease is challenging to the clinicians as the disease process is discontinuous and shows periods of exacerbation and remission. Traditional diagnostic methods basically tells about the past tissue destruction so new diagnostic methods are required which is able to detect the active state of the disease, determine the future progression and also estimates the response to the therapy, thereby helping in the better clinical management of the patient. Both saliva and Gingival crevicular fluid (GCF) are believed to be reliable medium to detect the biomarkers which plays a pivotal role in measuring the disease activity. Keeping these observations in mind rapid chairside tests are developed to diagnose periodontal disease called as Point of Care (POC) diagnostics which simplifies diagnosis and helps in improving the prognosis. This review article highlights about the biomarkers used in the diagnosis and throws light on the various available point of care diagnostic devices.

The detection of BANA micro-organisms in adult periodontitis before and after scaling and root planing by BANA-Enzymatic™ test kit: An in vivo study

Background:

Many paraclinical methods are available today for an accurate assessment of the periodontal status prior and during the periodontal treatment. The microbial-enzymatic N-benzoyl-DL-arginine-2-napthylamide (BANA) test is one of the modern alternatives to bacterial cultures. It detects the presence of three periodontal pathogens in the subgingival plaque (Porphyromonas gingivalis, Treponema denticola and Tannerella forsythia).

Aims and Objective:

The aim and objective of this study was to detect the presence of BANA micro-organisms and also to determine the effect of scaling and root planning in adult periodontitis patients.

Materials and Methods:

A total number of 20 patients (80 sites) all having periodontitis were selected. Four test sites (permanent molar from each quadrant) were selected from each patient and assessed for plaque index, bleeding index and pocket depth before and after scaling and root planning. BANA test was used for the detection and prevalence of the “red complex” bacteria in plaque samples.

Results:

Showed that the BANA tests are statistically correlated with the severity of periodontal destruction. There was a significant correlation between the BANA test results and the quantity of bacterial plaque, the test being influenced by the composition of bacterial plaque.

Conclusion:

This study encourages the use of such chair-side tests for a proper diagnosis of periodontal disease and for a good evaluation of the treatment results.

Halitosis: From diagnosis to management

Halitosis is formed by volatile molecules which are caused because of pathological or nonpathological reasons and it originates from an oral or a non-oral source. It is very common in general population and nearly more than 50% of the general population have halitosis. Although halitosis has multifactorial origins, the source of 90% cases is oral cavity such as poor oral hygiene, periodontal disease, tongue coat, food impaction, unclean dentures, faulty restorations, oral carcinomas, and throat infections. Halitosis affects a person's daily life negatively, most of people who complain about halitosis refer to the clinic for treatment but in some of the people who can suffer from halitosis, there is no measurable halitosis. There are several methods to determine halitosis. Halitosis can be treated if its etiology can be detected rightly. The most important issue for treatment of halitosis is detection etiology or determination its source by detailed clinical examination. Management may include simple measures such as scaling and root planning, instructions for oral hygiene, tongue cleaning, and mouth rinsing. The aim of this review was to describe the etiological factors, prevalence data, diagnosis, and the therapeutic mechanical and chemical approaches related to halitosis.

Salivary diagnostics for periodontal diseases

BACKGROUND

and Overview The use of salivary diagnostics continues to develop and advance the field of risk determination for periodontal diseases. Researchers are investigating genetic, microbial and protein biomarkers with the objective of translating findings to such aspects of clinical care as broad patient screening, monitoring and treatment planning.

METHODS

/st> In this review, the author briefly explores currently available salivary diagnostics used to identify bacteria prevalent in periodontal disease, and focuses on the future development and use of a variety of rapid disease detection platforms, such as lab-on-a-chip, as a point-of-care device for identification of patients' risk.

CONCLUSIONS

and

CLINICAL IMPLICATIONS

/st> Several diagnostic tests are commercially available, and point-of-care tests are under development. However, challenges remain regarding the introduction of these technologies to clinical practice and adoption by dental practitioners for promotion of personalized oral health care.

Salivary proteolytic activities in periodontitis, gingivitis and diabetes mellitus

Elastase activity was found to be significantly increased in periodontitis (0.872±0.4270 absorbance units/mg protein, mean±S. D., 1.05±0.61 units/ml saliva), gingivitis (0.772±0.416 units/mg protein, 1.515±0.952 units/ml) and diabetes (0.549±0.286 units/mg protein, 1.20±0.769 units/ml) compared to normals (0.255±0.089) units/mg protein, 0.264±0.079 units/ml). Chymotryptic activity was not found to be increased in these disease conditions over the normal level (0.284±0.096 units/mg protein). Aminopeptidase activity was elevated only in periodontitis (0.670+0.140 units/mg protein) compared to normals (0.349±0.100 units/mg protein). Trypsin-like activity was also found to be significantly raised in periodontitis compared to normals when Pro-Phe-Arg-p-nitroanilide (0.666±0.204 units/mg protein), Ile-Pro-Arg-p-nitroanilide (1.59±0.260 units/mg protein) and Pyroglu-Pro-Arg-p-nitroanilide (1.82±0.380 units/mg protein) were used as substrates. The normal values with these three substrates were respectively, 0.454±0.110, 1.04±0.231 and 1.15±0.312 units/mg protein. Total protein level in saliva was found to be significantly elevated in gingivitis (209±66.8 mg/dl) and diabetes (204±68.0) compared to normal values (107±20.7). Increase in periodontitis was marginal (127±28.3 mg/dl). Expression of proteolytic activities normalized to protein level was useful in differential diagnosis. Increase in elastase level in saliva is not a specific marker for periodontal diseases.

Efficacy of locally-delivered doxycycline microspheres in chronic localized periodontitis and on Porphyromonas gingivalis

AIM

This study aimed to assess the efficacy and effect of locally-delivered doxycycline microspheres with scaling and root planing in periodontal pocket therapy and on Porphyromonas gingivalis, respectively.

METHODS

Twenty sites with a probing pocket depth of 4-6 mm were divided into two groups: a control group consisting of scaling and root planing, with one application of doxycycline microspheres only at baseline, and a test group consisting of scaling and root planing, with an application of doxycycline microspheres at baseline and 1 and 3 months. Clinical readings included the plaque index, gingival index, probing pocket depth, and relative attachment level. Rapid polymerase chain reaction method was used for the detection of P. gingivalis.

RESULTS

A statistically-significant reduction in probing pocket depth and attachment gain was found in both groups; the test group showed a significant reduction in probing pocket depth and attachment gain compared with the control at 3 and 6 months. P. gingivalis cell count in the test group was significantly reduced at all the time periods, except from 1 to 3 months.

CONCLUSION

Local drug delivery of doxycycline microspheres significantly improved the treatment outcomes in periodontal pocket therapy and reduced P. gingivalis in the periodontal pocket.

Association between pneumonia and oral care in nursing home residents

Pneumonia remains the leading cause of death in nursing home residents. The accumulation of dental plaque and colonization of oral surfaces and dentures with respiratory pathogens serves as a reservoir for recurrent lower respiratory tract infections. Control of gingivitis and dental plaques has been effective in reducing the rate of pneumonia but the provision of dental care for institutionalized elderly is inadequate, with treatment often sought only when patients experience pain or denture problems. Direct mechanical cleaning is thwarted by the lack of adequate training of nursing staff and residents' uncooperativeness. Chlorhexidine-based interventions are advocated as alternative methods for managing the oral health of frail older people; however, efficacy is yet to be demonstrated in randomized controlled trials. Development and maintenance of an oral hygiene program is a critical step in the prevention of pneumonia. While resources may be limited in long-term-care facilities, incorporating oral care in daily routine practice helps to reduce systemic diseases and to promote overall quality of life in nursing home residents.

Respiratory disease and the role of oral bacteria

The relationship between oral health and systemic conditions, including the association between poor oral hygiene, periodontal disease, and respiratory disease, has been increasingly debated over recent decades. A considerable number of hypotheses have sought to explain the possible role of oral bacteria in the pathogenesis of respiratory diseases, and some clinical and epidemiological studies have found results favoring such an association. This review discusses the effect of oral bacteria on respiratory disease, briefly introduces the putative biological mechanisms involved, and the main factors that could contribute to this relationship. It also describes the role of oral care for individuals who are vulnerable to respiratory infections.

Identification of pathogen and host-response markers correlated with periodontal disease

BACKGROUND

Periodontitis is the major cause of tooth loss in adults and is linked to systemic illnesses, such as cardiovascular disease and stroke. The development of rapid point-of-care (POC) chairside diagnostics has the potential for the early detection of periodontal infection and progression to identify incipient disease and reduce health care costs. However, validation of effective diagnostics requires the identification and verification of biomarkers correlated with disease progression. This clinical study sought to determine the ability of putative host- and microbially derived biomarkers to identify periodontal disease status from whole saliva and plaque biofilm.

METHODS

One hundred human subjects were equally recruited into a healthy/gingivitis group or a periodontitis population. Whole saliva was collected from all subjects and analyzed using antibody arrays to measure the levels of multiple proinflammatory cytokines and bone resorptive/turnover markers.

RESULTS

Salivary biomarker data were correlated to comprehensive clinical, radiographic, and microbial plaque biofilm levels measured by quantitative polymerase chain reaction (qPCR) for the generation of models for periodontal disease identification. Significantly elevated levels of matrix metalloproteinase (MMP)-8 and -9 were found in subjects with advanced periodontitis with Random Forest importance scores of 7.1 and 5.1, respectively. The generation of receiver operating characteristic curves demonstrated that permutations of salivary biomarkers and pathogen biofilm values augmented the prediction of disease category. Multiple combinations of salivary biomarkers (especially MMP-8 and -9 and osteoprotegerin) combined with red-complex anaerobic periodontal pathogens (such as Porphyromonas gingivalis or Treponema denticola) provided highly accurate predictions of periodontal disease category. Elevated salivary MMP-8 and T. denticola biofilm levels displayed robust combinatorial characteristics in predicting periodontal disease severity (area under the curve = 0.88; odds ratio = 24.6; 95% confidence interval: 5.2 to 116.5).

CONCLUSIONS

Using qPCR and sensitive immunoassays, we identified host- and bacterially derived biomarkers correlated with periodontal disease. This approach offers significant potential for the discovery of biomarker signatures useful in the development of rapid POC chairside diagnostics for oral and systemic diseases. Studies are ongoing to apply this approach to the longitudinal predictions of disease activity.

Professional oral care reduces influenza infection in elderly

Influenza is a major cause of respiratory infection and has a high mortality rate in the elderly. Neuraminidase (NA) on the surface of the influenza virus and bacterial trypsin-like proteases (TLP) play key roles in influenza virus infections. We investigated the effects of oral care on influenza, evaluating in particular the activities of NA and TLP in saliva, as they may contribute to an increased risk of infection with influenza. One hundred ninety elderly patients who visited day care service facilities once a week were randomly assigned to either a professional oral care group or to an own oral care group as the control group. Nine individuals in the control group and one person in the professional oral care group were diagnosed with influenza during the follow-up period. The relative risk of developing influenza while under professional oral care compared to that in the control group was 0.1 (95% CI 0.01-0.81, p=0.008). Significant decreases in numbers of salivary anaerobic bacterial CFUs, and NA and TLP levels were observed in the professional oral care group compared to that in the control group (p<0.01). This study suggests that maintenance of oral hygiene is effective in the prevention of influenza in the elderly.

Gingival crevicular fluid levels of aspartate amino transferase, sulfide ions and N-benzoyl-DL-arginine-2-naphthylamide in diabetic patients with chronic periodontitis

BACKGROUND

The aim of this study is to analyze the correlations between plaque index (PlI), gingival index (GI), probable pocket depth (PPD), clinical attachment level (CAL), aspartate aminotransferase (AST), N-benzoyl-DL-arginine-2-naphthylamide (BANA) and sulfide ion activity (SIA) of diabetic patients with chronic periodontitis with regard to disease activity detected by AST levels.

MATERIAL AND METHODS

A total of 95 sites from eight diabetic patients with chronic periodontitis and 74 sites from eight systemically healthy patients with chronic periodontitis were enrolled in the study. The patients had no history of periodontal treatment or any antibiotic therapy during the last 6 months and were nonsmokers. All the sites selected for the study had a CAL of at least 2 mm. Gingival crevicular fluid volumes (GCFV) were measured in all sites.

RESULTS

According to the result of AST analysis, 45 sites were AST positive and 50 were AST negative in the diabetic group and 36 sites were AST positive and 38 were AST negative in the control group. There was a significant correlation between BANA hydrolysis and PPD in both diabetic and control groups, but no correlation between PPD and AST levels. A significant correlation was observed between AST-positive sites and GI, but not between GI and BANA hydrolysis. In both groups, the correlation between SIA and BANA hydrolysis was significant, but no correlation was revealed between SIA and AST levels in either diabetic or control groups.

CONCLUSION

The GCF metabolites had significant correlations with periodontally diseased sites in patients with chronic periodontitis, whether diabetic or systemically healthy, and may help to confirm clinical findings.

Inhibitory effect of procyanidin oligomer from elm cortex on the matrix metalloproteinases and proteases of periodontopathogens

OBJECTIVES

The purpose of this study was to evaluate a partially purified extract (elm extract) from the Ulmi cortex (Ulmi macrocarpa Hance) and its active ingredient, a mix of procyanidin oligomers (3 to 12 flavan-3-ol monomers, an average molecular weight of 1,518 with an average polymerization degree of 5.3) for a possible inhibitory effect against proteases.

BACKGROUND

Host-derived matrix metalloproteinases (MMPs) and bacterial proteases play important roles in the gingival tissue destruction that is a characteristic of periodontitis. The inhibitors of these proteases may be developed into therapeutic agents against periodontitis.

METHODS

The inhibitory effects were assessed by gelatin zymography. The MMPs tested were originated from the gingival crevicular fluid (GCF) of adult periodontitis patients and from the conditioned media of cultured periodontal ligament (PDL) cells, which provided the proMMP-2 and activated MMP-2 when treated with a periodontopathogen, Treponema lecithinolyticum. Bacterial enzymes tested were secreted forms from two major periodontopathogens, Porphyromonas gingivalis and Treponema denticola. In addition, the inhibitory effects on trypsin-like enzymes from these two periodontopathogens were assayed by the n-benzoyl-DL-arginine-naphthylamide (BANA) test.

RESULTS

The elm extract and the procyanidin oligomer (100-1,000 microg/ml) exhibited potent inhibitory effects on the MMPs in GCF (chiefly MMP-8 and MMP-9), the pro and active forms of MMP-2, and secreted and trypsin-like enzymes from T. denticola and P. gingivalis.

CONCLUSIONS

These results suggest that elm cortex should be considered as a potential agent against periodontal diseases, due to its inhibitory action on MMPs and the proteases of periodontopathogens.

Effect of a controlled-release chlorhexidine chip on clinical and microbiological parameters of periodontal syndrome

AIM

The aim of this study was to evaluate the effectiveness of a controlled-released chlorhexidine chip (CHX) as adjunctive therapy to scaling and root planing (SRP) in the treatment of chronic periodontitis.

MATERIAL AND METHODS

Twenty patients with at least four sites with probing depth >or= 5 mm and bleeding on probing were selected. This randomized single-blind study was carried out in parallel design. The control group received SRP alone, while the test group received SRP plus CHX chip. The clinical parameters, Plaque Index (PlI), Papillary Bleeding Score (PBS), Bleeding on Probing (BOP), Gingival Recession (GR), Probing Depth (PD) and Relative Attachment Level (RAL), and the microbiological parameter BANA test were recorded at baseline and after 3, 6 and 9 months.

RESULTS

Both groups presented significant improvements in all parameters analyzed over the study period. There were no statistically significant differences between the two groups for any parameter analyzed after 9 months, except for BOP, which was significantly reduced in the control group. The mean reductions on PD and RAL were 2.4 mm and 1.0 mm for the control group and 2.2 mm and 0.6 mm for the test group, respectively.

CONCLUSION

The CHX chip did not provide any clinical or microbiological benefit beyond that achieved with conventional scaling and root planning, after a 9-month period.

Clinical and microbiological studies of periodontal disease in Sjögren syndrome patients

BACKGROUND

Little is known about the periodontal status of patients with Sjögren's Syndrome (SS), a chronic inflammatory autoimmune disease characterized by xerophthalmia and xerostomia. The aim of the present study was to evaluate whether the periodontal status of SS patients, in terms of clinical and microbiological parameters, differs from systemically healthy age- and gender-matched controls.

METHODS

8 primary SS and 10 secondary SS patients were examined in comparison with 11 control subjects. All patients were diagnosed by the European Community Criteria. Control subjects were systemically healthy and not undergoing periodontal treatment. The comparison of clinical status was made in terms of mean periodontal parameters (plaque index, gingival index, gingival recession, probing pocket depth, probing attachment level and bleeding on probing) as well as the frequency distribution of probing pocket depth and probing attachment level measurements. Microbiological assays of the subgingival dental plaque samples were carried out by both a chairside enzyme test (Periocheck) for the detection of peptidase activity (PA) and a polymerase chain reaction (PCR) analysis for 9 selected periodontal micro-organisms (Actinobacillus actinomycetemcomitans, Fusobacterium nucleatum, Prevotella intermedia, Treponema denticola, Porphyromonas gingivalis, Eikenella corrodens, Campylobacter rectus, Bacteroides forsythus, Streptococcus oralis).

RESULTS

The occurrence, severity and extent of periodontal lesions were not significantly different between the 3 patient groups for all periodontal parameters examined. No significant differences in the sub-gingival plaque samples from control, primary or secondary SS patients for the PA test, frequency or type of periodontal micro-organisms observed.

CONCLUSION

No significant differences could be detected in either clinical or microbiological parameters of primary or secondary SS patients compared with that of control subjects. The results of the present study thus support the notion that the periodontal status of patients with SS do not differ from systemically healthy age- and gender-matched controls.

The opdB locus encodes the trypsin-like peptidase activity of Treponema denticola

High levels of Treponema denticola in subgingival dental plaque are associated with severe periodontal disease. T. denticola, along with Porphyromonas gingivalis and Bacteroides forsythus, are the only cultivatable oral microorganisms that produce significant amounts of "trypsin-like" peptidase activity. The ability of subgingival plaque to hydrolyze N-alpha-benzoyl-DL-arginine-2-naphthylamide (BANA) is associated with high levels of one or more of these organisms. The purpose of this study was to identify the gene encoding trypsin-like activity in T. denticola and thus facilitate molecular-level studies of its potential role in disease. Using published peptide sequences of a T. denticola surface-associated oligopeptidase with BANA-hydrolyzing activity, we identified the gene, designated opdB, in an apparently noncoding region of the T. denticola genome unannotated contigs (11/2000; http://www.tigr.org). The opdB gene begins with a TTG start codon and encodes a 685-residue peptide with high homology to the oligopeptidase B family in prokaryotes and eukaryotes. An isogenic T. denticola opdB mutant was constructed by allelic replacement mutagenesis using an ermF/AM gene cassette. The mutant lacked BANA-hydrolyzing activity and had a slightly slower growth rate than the parent strain. This mutant will be used in future studies of interactions of T. denticola with host cells and tissue.

Systemic diseases caused by oral infection

Recently, it has been recognized that oral infection, especially periodontitis, may affect the course and pathogenesis of a number of systemic diseases, such as cardiovascular disease, bacterial pneumonia, diabetes mellitus, and low birth weight. The purpose of this review is to evaluate the current status of oral infections, especially periodontitis, as a causal factor for systemic diseases. Three mechanisms or pathways linking oral infections to secondary systemic effects have been proposed: (i) metastatic spread of infection from the oral cavity as a result of transient bacteremia, (ii) metastatic injury from the effects of circulating oral microbial toxins, and (iii) metastatic inflammation caused by immunological injury induced by oral microorganisms. Periodontitis as a major oral infection may affect the host's susceptibility to systemic disease in three ways: by shared risk factors; subgingival biofilms acting as reservoirs of gram-negative bacteria; and the periodontium acting as a reservoir of inflammatory mediators. Proposed evidence and mechanisms of the above odontogenic systemic diseases are given.

Measurement of peptidase activity and evaluation of effectiveness of administration of minocycline for treatment of dogs with periodontitis

OBJECTIVE

To determine clinical, enzymatic, and microbiologic effects of controlled-release localized administration of minocycline on dogs with periodontitis.

ANIMALS

Five adult Beagles with periodontitis.

PROCEDURE

After tooth scaling and root planing, 2 treatment, 1 placebo, and 1 control site were selected for each dog. Treatment sites (n = 10) received a periodontal formulation of minocycline hydrochloride, placebo sites (5) received ointment without minocycline, and control sites (5) did not receive ointment. Treatments were administered 4 times at weekly intervals. Peptidase activity and clinical and microbiologic effects were evaluated and compared among sites for 17 weeks.

RESULTS

Bleeding of the gums on probing (BOP) and pocket depth (PD) improved at the treatment site and were maintained for 13 weeks after treatment. However, BOP and PD in placebo and control sites increased from weeks 9 to 17 Peptidase activity in the periodontal pocket decreased noticeably from week 1 to 17, compared with baseline values for the treatment site. However, peptidase activity for placebo and control sites increased and were above baseline values on week 9 and week 13, respectively. Total bacterial counts decreased by 90% for treatment sites and remained at that value for 13 weeks. However, for placebo and control sites, bacterial counts increased and reached the baseline value on week 17.

CONCLUSIONS AND CLINICAL RELEVANCE

Increased peptidase activity is correlated with the progression of periodontitis in dogs. Treatment with minocycline, using a localized delivery system, was effective in dogs for at least 13 weeks after cessation of drug administration.

Systemic diseases caused by oral infection

Recently, it has been recognized that oral infection, especially periodontitis, may affect the course and pathogenesis of a number of systemic diseases, such as cardiovascular disease, bacterial pneumonia, diabetes mellitus, and low birth weight. The purpose of this review is to evaluate the current status of oral infections, especially periodontitis, as a causal factor for systemic diseases. Three mechanisms or pathways linking oral infections to secondary systemic effects have been proposed: (i) metastatic spread of infection from the oral cavity as a result of transient bacteremia, (ii) metastatic injury from the effects of circulating oral microbial toxins, and (iii) metastatic inflammation caused by immunological injury induced by oral microorganisms. Periodontitis as a major oral infection may affect the host's susceptibility to systemic disease in three ways: by shared risk factors; subgingival biofilms acting as reservoirs of gram-negative bacteria; and the periodontium acting as a reservoir of inflammatory mediators. Proposed evidence and mechanisms of the above odontogenic systemic diseases are given.

The relationship between place BANA reactivity and clinical parameters in subjects with mental disabilities

The purpose of the present investigation was to determine whether subjects institutionalized with mental retardation have a relationship between periodontal clinical parameters and the presence of the BANA-positive periodontal pathogens Porphyromonas gingivalls, Treponema denticola, and Bacteroides forsythus in their subgingival plaques. Fifty institutionalized subjects (25 patients with Down syndrome and 25 subjects with mental retardation) were matched with respect to age and sex. Periodontal clinical parameters (Bleeding on Probing, BOP; Papillary Bleeding Score, PBS; and Probing Depth, PD) were obtained from 6 reference teeth (3, 8, 14, 19, 24, 30). In addition, subgingival plaque samples taken from the same 6 teeth were analyzed for the presence of the BANA-positive species, by means of the chairside BANA test. In both the patients with Down syndrome and the group with mental retardation, the presence of BANA-positive plaques was significantly associated with bleeding on probing (p < 0.05) and increased probing depth (p < 0.01, Chi-square). Analysis of these data indicated that the BANA test could be used in combination with clinical criteria to diagnose a periodontopathy anaerobic infection in institutionalized subjects.

Role of oral bacteria in respiratory infection

An association between oral conditions such as periodontal disease and several respiratory conditions has been noted. For example, recent evidence has suggested a central role for the oral cavity in the process of respiratory infection. Oral periodontopathic bacteria can be aspirated into the lung to cause aspiration pneumonia. The teeth may also serve as a reservoir for respiratory pathogen colonization and subsequent nosocomial pneumonia. Typical respiratory pathogens have been shown to colonize the dental plaque of hospitalized intensive care and nursing home patients. Once established in the mouth, these pathogens may be aspirated into the lung to cause infection. Other epidemiologic studies have noted a relationship between poor oral hygiene or periodontal bone loss and chronic obstructive pulmonary disease. Several mechanisms are proposed to explain the potential role of oral bacteria in the pathogenesis of respiratory infection: 1. aspiration of oral pathogens (such as Porphyromonas gingivalis, Actinobacillus actinomycetemcomitans, etc.) into the lung to cause infection; 2. periodontal disease-associated enzymes in saliva may modify mucosal surfaces to promote adhesion and colonization by respiratory pathogens, which are then aspirated into the lung; 3. periodontal disease-associated enzymes may destroy salivary pellicles on pathogenic bacteria to hinder their clearance from the mucosal surface; and 4. cytokines originating from periodontal tissues may alter respiratory epithelium to promote infection by respiratory pathogens.

Implications of oral infections on systemic diseases in the institutionalized elderly with a special focus on pneumonia

Systemic infection in the elderly patient living in a chronic care setting presents a significant burden to the health care system. The extent to which oral organisms cause systemic infections through hematogenous dissemination in the institutionalized elderly is still unknown. A more likely and common route of systemic infection by oral microorganisms is through aspiration of oropharyngeal fluids containing oral pathogenic microorganisms, which colonize the lower respiratory tract and cause pneumonia. Respiratory pathogens emerge in the dental plaque of elderly patients with very poor oral hygiene and severe periodontal disease. In the chronic care setting, aspiration of oropharyngeal fluids contaminated with these bacteria occurs in patients with diminished host defenses, resulting in bacterial pneumonia. This is also a problem in intensive care units in the hospital setting. In one study, pre-rinsing with a 0.12% chlorhexidine gluconate mouthwash significantly lowered the mortality rate from postsurgical pneumonia in patients undergoing open heart surgery. Selective digestive decontamination, a technique involving the topical application of antimicrobials to reduce the risk of colonization of the respiratory tract, has been used to reduce the incidence of nosocomial pneumonia in the acute care setting of hospitals. This technique has not been employed in the nursing home setting. Whether improving oral hygiene would also lower the risk in either of these settings has not been studied. A number of obstacles must be overcome in designing studies to investigate the relationship between oral infections and lung infections in the institutionalized elderly. Ethical issues must be addressed, and full collaboration of the medical team is required. Future studies should establish whether reducing the risk for pneumonia in the institutionalized elderly is possible through improved oral health.

A relationship between proteinase activity and clinical parameters in the treatment of periodontal disease

The objective of this research was to determine the effectiveness of a biochemical assay which measures proteolytic enzyme activity in gingival crevicular fluid (GCF) and to relate this enzyme activity to clinical parameters traditionally utilized for periodontitis detection. A clinical trial was conducted on 8 periodontitis subjects with > or =4 sites exhibiting a loss of attachment of > or =5 mm and probing depths of > or =5 mm with bleeding on probing. On each subject, a plaque index was performed, followed by GCF sampling at those sites which exhibited a loss of attachment and probing depths. GCF was analyzed for activity against benzoyl-L-arginine-p-nitroanilide in the presence (BAPNA w/gly-gly) and the absence (BAPNA w/o gly-gly) of glycyl-glycine and against MeOSuc-Ala-Ala-Pro-Val-pNA and Suc-Ala-Ala-Pro-Phe-pNA for neutrophil serine proteinases activity (elastase and cathepsin G, respectively). Subsequently, a gingival index was performed, attachment levels and probing depths were recorded using a constant force probe with bleeding on probing being noted. A split-mouth design was employed and half mouths were randomly assigned to the following treatment groups: group A, half of the mouth received scaling/root planing and polishing: group B, half of the mouth received no treatment (control). Subjects were treated, then instructed on toothbrushing and interdental cleaning. After 4 weeks, subjects returned to receive a plaque index; GCF sampling, gingival index, attachment levels, probing depths and bleeding on probing as described above. Using a paired Student t-test, the findings suggest that BAPNA w/gly-gly was significantly less in treatment sites than in non-treated control sites (p=0.05). No such correlation was found for other activities, including neutrophil serine proteinases which were shown to occur in GCF in free, proteolytically active forms. In addition, significant treatment effects were detected for probing depths (p= 0.03) which reduced by 1.3 mm and attachment levels (p=0.02) which gained 0.7 mm. The reduction of P. gingivalis from treated periodontitis sites as detected by a significant decrease in BAPNA w/ gly-gly may prove to be a valuable marker for periodontal disease activity.

Microbial factors and gingival crevicular fluid aspartate aminotransferase levels. A cross-sectional study

The aim of this cross-sectional study was to investigate the clinical application of chairside tests for gingival crevicular fluid (GCF) aspartate aminotransferase (AST) levels and plaque BANA hydrolysis activity with the presence of the periodontal pathogens Porphyromonas gingivalis and Actinobacillus actinomycetemcomitans. The study comprised 100 periodontitis sites (pocket depths > or =4 mm, GI=3) from 10 patients with chronic adult periodontitis and 100 control sites (pocket depths <4 mm, GI<3) from 10 periodontally healthy patients comprising 55 healthy sites (pocket depths <4 mm, GI=0) and 45 gingivitis sites (pocket depths <4 mm, GI=1 or 2). The values for both BANA hydrolysis and AST levels were significantly higher in samples from periodontitis compared with gingivitis and healthy sites (p<0.001). A. actinomycetemcomitans was identified in 45% and P. gingivalis in 17% of periodontitis sites but neither pathogen was recovered from control sites and there was no significant correlation with the clinical parameters measured. There was no significant relationship between the presence of P. gingivalis and/or A. actinomycetemcomitans with BANA hydrolysis or AST levels. A significant correlation (p=0.0017) was observed between BANA hydrolysis and pocket depth and between AST hydrolysis and the GI (p=0.01). This study failed to demonstrate a positive association between chairside analysis of GCF metabolites for AST levels and/or BANA hydrolysis with P. gingivalis and A. actinomycetemcomitans. However, the GCF metabolites had a significant correlation with periodontally diseased sites in patients with chronic adult periodontitis and may help confirm clinical observations.

Environmental effects on the growth and proteolysis of Treponema denticola ATCC 33520

The effect of pH, redox potential, O2 and H2 on the growth and proteolytic activity of Treponema denticola ATCC 33520 was studied in a chemostat at different growth rates. The peptidase and protease activities were estimated using different amido-methyl coumarin derivatives and azocasein. The maximum growth rate of T. denticola ATCC 33520 was 0.14 h-1. Reduction of the growth rate of T. denticola by 50-60% gave: an increase in cell mass of 150-200%, a higher acetogenesis and a shift of the pH optimum. The protease and phenylalanine peptidase activities seemed to be of greater importance for the growth of T. denticola ATCC 33520 than the rather low arginine and proline peptidase activities. The redox potential (Eh) played a secondary role. At microaerophilic conditions with 1-5% O2, the cultures maintained a redox potential below -311 mV and an optimal acetogenesis. The presence of H2 induced a marked growth stimulation of T. denticola ATCC 33520. It is concluded that the cell mass and proteolytic activity of T. denticola ATCC 33520 are modulated by the growth rate and the pH and to a lesser extend by the redox potential and presence of O2. Stagnation of the exudate-flow influences these factors and will lead to an increase of the spirochetal population and proteolysis in the periodontal pocket.

A 5-year study of attachment loss and tooth loss in community-dwelling older adults

Tooth loss is a widely recognized endpoint measure for the effects of periodontal diseases and the impact of periodontal therapy. In fact, traditional clinical measures of periodontal status often are considered to be surrogate endpoints in that they are assumed to be related to tooth loss. However, the strength of the relationship between attachment loss and tooth loss in a representative population of untreated subjects has not been studied extensively. The purpose of this paper is to present the trends in attachment loss over a 5-yr period in a population of community-dwelling elderly blacks and whites. Specifically, this paper presents attachment loss trends both at the person and tooth level to address the following issues; 1) whether teeth that experience attachment loss during 1 time period are more likely to be lost at the next time period; and 2) given similar levels of attachment loss, why are some people more likely to lose teeth? In 1988, the University of North Carolina School of Dentistry initiated the Piedmont 65+ Dental Study, which was designed to elicit 800 dentate respondents in the 5-country area who were examined again at 18, 36 and 60 months. Our findings indicated that teeth with poorer attachment level at baseline had a higher probability of being lost during the next 5 yr and teeth that experienced attachment loss during a time period were more likely to be lost during the next time period than teeth without additional attachment loss. In addition, it appears that there are person-level characteristics associated with increasing tendency towards tooth loss in people with similar periodontal status, a finding that may clarify the relationship between attachment loss and tooth loss.

A 5-year study of attachment loss in community-dwelling older adults: incidence density

This is the second of three papers that present trends in attachment loss and tooth loss over a 5-yr period in a population of community-dwelling elderly black and whites. The first paper in this series showed that in addition to subject attrition during the 5 yr of the study, teeth also were lost. This loss of subjects and teeth resulted in trends that were not always consistent over time, because people were lost from the study and teeth with more active and advanced periodontal disease were more likely to be lost. In these instances, the incidence density (time-to-event) analytic strategy is useful. Incidence density is the average rate of occurrence for a fixed follow-up period. In 1988, the University of North Carolina School of Dentistry initiated the Piedmont 65+ Dental Study, which was designed to elicit 800 dentate respondents in the 5-county area who were examined again at 18, 36 and 60 months. Our findings indicated that for every 1000 sites followed for 1 yr in this population, 20.6 sites will experience attachment loss of 3+mm. Incidence densities varied greatly by subgroup, indicating that certain characteristics predispose sites for attachment loss. A multivariate logistic regression model indicated that people who are smokers, Porphyromonas gingivalis positive, have 5 or more missing teeth, are not high school graduates, and have not had a dental visit in the last 5 yr are at higher risk of attachment loss. Posterior teeth and mesiobuccal sites are at higher risk. We conclude that incidence density analyses are useful for longitudinal periodontal data and we illustrate the use of incidence density rates to plan clinical trials.

Assessment of pretreatment orthodontic patients using the BANA test. N-benzoyl-DL-arginine-naphthylamide

Ninety-two subjects were tested before orthodontic mechanotherapy for the presence of three putative periodontopathogens-Porphyromonas gingivalis, Treponema denticola, and Bacteroides forsythus-with the BANA test (PerioScan Oral-B). The sample ranged from 9 to 16 years, with a mean age of 13.1 years, and consisted of 51% girls and 49% boys; 48% African American, 46% white, 4% Asian, and 2% Hispanic. Unlike other BANA studies that examined children and adolescents with a 15-minute incubation time, this research used a 5-minute incubation time to increase the specificity and to reduce the false positives obtained from the PerioScan cards. No statistically significant difference was found between the age, gender, or race of the patients and the levels of the three putative periodontopathogens. A Friedman two-way analysis of variance assessed the BANA levels for three groups of teeth: molars, incisors, and premolars. The central incisors and first molars had a significantly higher percentage of positive BANA readings than the first premolars at p < or = 0.05. The clinical importance of this finding has yet to be determined, however, because the central incisor and first molar are the first permanent teeth to erupt, a possible association between dental emergence time and the rate of infection with various organisms may be postulated. In a pilot study, 10 patients from a statistically comparable pretreatment group were assessed longitudinally at two separate collection times separated by 4 months. The Wilcoxon signed rank test indicated no significant changes in these patients over the 4-month period.

Do root lesions tend to develop in the same people who develop coronal lesions?

OBJECTIVES

The three purposes of this study are to: (1) describe the relationship between the prevalence of coronal caries and root caries; (2) describe the relationship between the three-year incidence of coronal caries and root caries; and (3) if the two conditions are associated, develop a multiple regression model that identifies characteristics distinguishing people who had increments of both root caries and coronal caries from people who had increments of either coronal caries or root caries, or who had no new caries.

METHODS

Dental examinations and interviews were conducted in the homes of a randomly selected, stratified sample of people over the age of 65 years in five North Carolina counties. The relationships between coronal and root D and DF were analyzed through contingency table analyses, and ordinal logistic regression was used to identify characteristics that differentiated people who had both coronal and root D over the three years from people who had either coronal or root D and people who had no new disease.

RESULTS

Evidence of root and coronal caries in whites was much more likely to be in the form of fillings, while for blacks, it was more likely to be in the form of untreated decay. Prevalence rates of coronal and root D and DF were significantly associated for both blacks and whites. Incidence rates based on DF indicated that root and coronal caries were not associated in whites, but were associated in blacks. People more likely to experience both types of caries had more gingival recession at baseline, greater average attachment loss over the three years, and lactobacilli at baseline. In addition, the presence of Porphymonas gingivalis at three years was important for whites.

CONCLUSIONS

It appears that coronal and root caries do tend to appear together in the same individuals, but fillings attenuate that relationship. The impact of dental treatment on the epidemiology of dental caries appears to be considerable and calls into question whether the F component of the caries index is related to disease as defined by epidemiologic criteria.

Periodontal disease diagnosis: current status and future developments

OBJECTIVES

This manuscript attempts to critically review traditional and currently employed methods of periodontal diagnosis, in the light of current knowledge about individual patients and sites at risk of progressive periodontal attachment loss.

DATA SOURCES

Articles published over the last decade from international research journals, have demonstrated that existing methods of periodontal disease diagnosis are seriously deficient with respect to accuracy, their ability to predict ongoing or future disease activity and their ability to determine the current activity status of historically diseased sites.

STUDY SELECTION

Longitudinal studies have questioned the rationale behind traditional treatment regimes and underlined the importance of site-directed therapy to avoid potentially damaging instrumentation of quiescent or healthy sites. The recent explosion in local, less invasive chemotherapies for periodontal disease management has aimed at addressing the site-specific nature of this group of diseases, but the true benefits of such novel therapies cannot be realised until more accurate and specific diagnostic techniques become available.

CONCLUSIONS

The manuscript concludes that the range of clinical information collected by experienced periodontists using currently available technology is probably sufficient to manage mild-to-moderate chronic adult periodontitis. However, those patients at risk from more aggressive attachment loss, and those individuals that appear refractory to traditional therapies, require the development of more accurate diagnostic tests to compliment the revolution in site-specific therapies. A diagnostic model is presented, which attempts to draw together current and future diagnostic methods for managing the majority of periodontal disease types, and it is suggested that current diagnoses should include some assessment of "risk'.

The relationship between microbial factors and gingival crevicular fluid glycosaminoglycans in human adult periodontitis

Counts of cultivable Porphyromonas gingivalis, assays of microbial proteases and the concentration in gingival crevicular fluid of proteoglycan metabolites were investigated at periodontitis and gingivitis sites in 16 patients with chronic adult periodontitis before and after treatment. Two periodontitis sites and two gingivitis sites were selected from each patient on the basis of a clinical examination. Gingival crevicular fluid from each site was analysed for the concentrations of the glycosaminoglycans chondroitin-4-sulphate and hyaluronan and subgingival plaque samples were analysed for cultivable P. gingivalis and microbial trypsin-like proteases assayed by benzoyl-DL-arginine-naphthylamide (BANA) hydrolysis. Significantly higher concentrations (p = 0.007) of chondroitin-4-sulphate were found at periodontitis than gingivitis sites but there was no significant difference in hyaluronan (p = 0.36) between these sites. Although the majority of periodontal sites were P. gingivalis-negative (23/32), there were significantly higher concentrations of chondroitin-4-sulphate (p = 0.05) and hyaluronan (p = 0.04) at the P. gingivalis-positive, compared to negative, periodontitis sites. At BANA-positive periodontitis sites there were also higher concentrations of chondroitin-4-sulphate (p = 0.0015) and hyaluronan (p = 0.0001) than at BANA-positive gingivitis sites. There was a significant decrease in concentrations of chondroitin-4-sulphate and hyaluronan at periodontitis sites after treatment. This study lends support to the hypothesis that P. gingivalis may be actively involved in the destruction of connective tissue components at culture-positive sites but shows that elevated concentrations of connective tissue breakdown products may occur in gingival crevicular fluid from periodontal sites where this organism is absent.

Relationships between periodontal disease and bacterial pneumonia

Bacterial pneumonia is a prevalent and costly infection that is a significant cause of morbidity and mortality in patients of all ages. The continuing emergence of antibiotic-resistant bacteria (e.g., penicillin-resistant pneumococci) suggests that bacterial pneumonia will assume increasing importance in the coming years. Thus, knowledge of the pathogenesis of, and risk factors for, bacterial pneumonia is critical to the development of strategies for prevention and treatment of these infections. Bacterial pneumonia in adults is the result of aspiration of oropharyngeal flora into the lower respiratory tract and failure of host defense mechanisms to eliminate the contaminating bacteria, which multiply in the lung and cause infection. It is recognized that community-acquired pneumonia and lung abscesses can be the result of infection by anaerobic bacteria; dental plaque would seem to be a logical source of these bacteria, especially in patients with periodontal disease. It is also possible that patients with high risk for pneumonia, such as hospitalized patients and nursing home residents, are likely to pay less attention to personal hygiene than healthy patients. One important dimension of this personal neglect may be diminished attention to oral hygiene. Poor oral hygiene and periodontal disease may promote oropharyngeal colonization by potential respiratory pathogens (PRPs) including Enterobacteriaceae (Klebsiella pneumoniae, Escherichia coli, Enterobacter species, etc.), Pseudomonas aeruginosa, and Staphylococcus aureus. This paper provides the rationale for the development of this hypothesis especially as it pertains to mechanically ventilated intensive care unit patients and nursing home residents, two patient groups with a high risk for bacterial pneumonia.

Detection of Eikenella corrodens and Actinobacillus actinomycetemcomitans by use of the polymerase chain reaction (PCR) in vitro and in subgingival plaque

The purpose of the present investigation was to identify 2 putative periodontal pathogens: Eikenella corrodens and Actinobacillus actinomycetemcomitans by polymerase chain reaction (PCR) in vitro and in subgingival plaque. On the basis of published sequences coding for 16S rRNA two primer pairs were designed which amplify a 410 bp sequence from E. corrodens DNA and a 547 bp fragment from A. actinomycetemcomitans DNA, respectively. As few as 50 cells could be detected from pure bacterial cultures. Each of the two primer pairs was found to be specific in that it did not give any amplification product neither with cell lysates from the respective alternative bacterium nor with lysates obtained from other putative periodontal pathogens and other bacteria. The PCR method developed turned out to be a simple, rapid and reliable diagnostic tool for the detection of the target microorganisms in clinical samples.

Correlation between gingivain/gingipain and bacterial dipeptidyl peptidase activity in gingival crevicular fluid and periodontal attachment loss in chronic periodontitis patients. A 2-year longitudinal study

The aim of this study is to determine whether either gingival crevicular fluid (GCF) bacterial gingivain/gingipain or dipeptidyl peptidase (DPP) levels, total activity (TA) and concentration (EC), predict progressive attachment loss (AL) in 75 patients with moderate periodontitis. GCF was collected from 16 molar and premolar mesiobuccal sites and then clinical attachment level (CAL) and probing depth (PD) were measured with an electronic constant pressure probe. Lastly, gingival, gingival bleeding, and plaque indices were scored. Prior to the baseline visit, patients were given basic periodontal treatment after which the above procedures were repeated. In addition, carefully localized radiographs were taken of the test teeth and repeated annually. Patients were then seen every 3 months for 2 years and the clinical measurements repeated at each visit. In 48 patients, 124 AL sites, 91 rapid AL (RAL), and 33 gradual AL (GAL) were detected. Gingivain/gingipain and bacterial DPP levels (TA and EC) at RAL sites were significantly higher (P < or = 0.0001) than at paired control sites at the attachment loss time (ALT) and prediction time (PT). Mean levels over the study period of both proteases (TA and EC) at GAL sites were significantly higher (P < or = 0.0001) than those at paired control sites. The GCF levels of gingivain/gingipain were always higher than those of DPP. Critical values (CV) of 5 microU/30 seconds (TA) and 30 microU/microL (EC) for both proteases showed high sensitivity and specificity values for TA and EC, which were the same at both ALT and PT. The positive predictive values were higher for gingivain/ gingipain. Mean site levels, over the course of the study, of both proteases (TA and EC) were significantly higher (P < or = 0.0001) at AL, RAL, and GAL sites than non-attachment loss (NAL) sites in AL patients and mean patient levels were significantly higher (P < or = 0.0001) in AL, RAL, and GAL patients than NAL patients. These results indicate that both of these bacterial proteases in GCF may be predictors of periodontal attachment loss.

Oral fluid elastase as an indicator of periodontal health

The study was designed to find out whether oral elastase activity could be used as a simple biochemical indicator of periodontal health. Both stimulated whole saliva and water rinse samples were collected from subjects with different degrees of adult periodontitis, gingivitis or healthy periodontium. In both sample types, elastase was mostly bound to insoluble fraction and preferred valine containing synthetic substrate, similar to neutrophil elastase. The elastase measurement required very little manipulation or time and its reproducibility was found to be good. The elastase levels were found to be negligible in edentulous subjects and usually very low in subjects with healthy periodontium. In about 85% of periodontitis cases having at least 1 deep periodontal pocket ( > or = 6 mm), clearly elevated elastases levels were detected in both the saliva and r rinse samples. In advanced periodontitis cases, the colour reaction took place in 0.5 to 2 h. In localized periodontitis cases, 2- to 18-h incubations were required for positive reaction. There was a good correlation between the elastase activity and the number of deep periodontal pockets and the average community periodontal index of the subjects. Elastase activity was not a good indicator of gingivitis. About 45% of gingivitis cases were positive with the elastase test, and the enzyme values were not significantly increased in experimental gingivitis. In a longitudinal study on advanced periodontitis cases, elastase levels dropped dramatically as a result of clinically successful therapy, close to the values of healthy subjects. The oral elastase test could serve as a valuable adjunct in periodontal screening and assessment of treatment efficacy.

Analysis of cultivable Porphyromonas gingivalis with trypsin-like protease enzyme activity and serum antibodies in chronic adult periodontitis

OBJECTIVE

Trypsin-like protease (TLPase) enzyme produced by Porphyromonas gingivalis has been implicated as a virulence factor in the pathogenesis of periodontal disease. The aims of this study were to investigate the relationship between cultivable P. gingivalis, TLPase enzyme activity (BANA hydrolysis) and serum antibody levels against cell sonicate and a purified TLPase antigen from P. gingivalis W50.

MATERIALS AND METHODS

Sub-gingival plaque samples were cultured for levels of P. gingivalis together with a chairside analysis of TLPase enzyme activity (Perioscan) from periodontitis and gingivitis sites of adult periodontitis patients. A TLPase from P. gingivalis was purified by gel filtration and ion exchange chromatography from the vesicle fraction for use as a test antigen.

RESULTS

Elevated levels of P. gingivalis were found at periodontitis sites, however, there was no correlation with sub-gingival plaque TLPase enzyme activity. Adult periodontitis patients had higher levels of IgG and IgA against cell sonicate and TLPase antigens than did controls. Those patients who were P. gingivalis culture-positive demonstrated an elevated immune response against both cell sonicate and TLPase when compared to P. gingivalis culture-negative patients. Treatment resulted in an improvement of clinical indices and no cultivable P. gingivalis could be recovered from the treated sites and there was a concomitant decrease in IgG levels against the TLPase. There was no significant difference in BANA hydrolysis at gingivitis sites or periodontitis sites after treatment.

CONCLUSIONS

Further longitudinal studies are suggested to investigate the role of the TLPase in the response to treatment of chronic adult periodontitis patients.