Advanced Periodontal Lesions Research Articles

Histopathological and immunohistochemical changes of the marginal periodontium in patients with Turner syndrome.

Turner syndrome (TS) is characterized by partial or complete loss of a sexual chromosome, resulting in an incomplete development of the body, gonadic failure, cardiac and renal abnormalities, oro-dental changes, etc. In our study, we proposed to perform a histological and immunohistochemical (IHC) study of the periodontium changes in patients with TS. The biological material under study was represented by fragments of gingival mucosa harvested from 18 patients with TS who presented advanced periodontal lesions and required dental extractions. The fragments of gingival mucosa were processed by the classical histological technique of paraffin inclusion, subsequently the obtained sections being stained by the Hematoxylin–Eosin (HE) and examined under the optical microscope. For the IHC study, there were performed serial sections incubated with anti-cluster of differentiation (CD) 3, anti-CD20 and anti-CD68 antibodies for highlighting immune cells, as well as with anti-matrix metalloproteinase (MMP) 2 and anti-MMP8 antibodies for highlighting MMPs (MMP2 and MMP8) involved in the periodontal tissue lesions. In the present study, during the histological examination, there were observed morphological changes, both in the epithelium and in the gingival mucosa chorion. Epithelial changes consisted in the onset of acanthosis processes, in the thickening of the epithelium due to the increase of the spinous layer, as well as in the parakeratosis phenomenon. In the chorion, there was observed the presence of inflammatory infiltrates in various stages, presence of fibrosis (extended in some cases) and the presence of an important vascularization in some cases, with a high number of immunocompetent cells involved in the inborn immune response, but also in the adaptive one, as well as a more or less intense immunoexpression of MMP2 and MMP8. Our study suggests that TS may contribute to the development of some inflammatory processes in the marginal periodontium.

Disentangling Cro-Magnon: The dental and alveolar remains

The dental and alveolar remains of the Upper Paleolithic early modern humans from the Abri de Cro-Magnon (Dordogne, France) are described and reassessed, building on descriptions since their discovery in 1868. There are four individuals represented; two (Cro-Magnon (CM) 4253 and 4254) are portions of numbered skulls (Cro-Magnon 1 and 2) and two (Cro-Magnon 4256 and 4257/58) are unassociated but likely deriving from Cro-Magnon 3 and 4. CM 4253 exhibits advanced periodontal lesions, likely secondary to tooth wear, CM 4256 has moderate alveolar resorption, but the others show little alveolar pathology. CM 4253, 4256 and 4257 have premolar rotation, and CM 4257/58 had impacted M3s. The CM 4254 molars are average in size for the Late Pleistocene, but those of CM 4257/58 are at or beyond the upper limits of known ranges of Upper Paleolithic variation. Only the dental dimensions of the CM 4257/58 molars are exceptional for earlier Upper Paleolithic humans.

Multidisciplinary prognostic transition of a molar tooth for long-term survival

Patients with periodontitis may have one or few teeth with hopeless prognosis, which would have to be extracted before initiation of orthodontic therapy. Periodontal therapy aims to prolong the lifespan of dentition, as preserving natural dentition is always the best treatment option. The decision to retain a tooth is always based on the probability of long-term success of one or more treatment modality. A 17-year-old female patient seeking fixed orthodontic treatment presented with the left mandibular first molar tooth (36) having hopeless periodontal prognosis with advanced primary periodontal and secondary endodontic lesion, grade III mobility, and grade II furcation involvement. Root canal treatment followed by periodontal surgery using a combination of bone graft (allograft) and platelet-rich fibrin membrane resulted in a clinical and radiographic indication of periodontal healing. The tooth (36) was even used for orthodontic anchorage 3-month postsurgically and was maintained for 2 years. Appropriate diagnosis and meticulous multidisciplinary treatment approach can lead to the restoration of health and function of the teeth with severe loss of attachment and bone loss and can even be used for orthodontic anchorage.

REDUCTION OF MOBILITY OF PERIODONTALY AFFECTED TEETH AFTER GINGIVAL AUGMENTATION WITH AN AUTOGENOUS GINGIVAL GRAFT (Case Report).

INTRODUCTION: The most severe complication of advanced periodontal lesions is the loss of teeth due to terminal attachment loss and high grade mobility. The goals of the treatment are the improving the plaque control stabilizing of the mobile teeth and arresting of the progression of gingival recession achieving gingival augmentation with adequate vestibulum depth. The autogenous graft is considered to be the most efficient approach where a significant increase of the attached gingiva is needed. OBJECTIVE: This presentation demonstrates the capacity of the autogenous gingival graft approach to reduce the high grade tooth mobility and to augment keratinized gingiva. METHODS: V.T. (46) with moderate generalized periodontitis. The examination reveals thin periodontal biotype, Class IV recessions on 31,41 with III grade mobility and terminal attachment loss, narrow vestibulum and lack of attached gingiva. An autogenous graft technique was selected to achieve simultaneous gingival augmentation and correction of vestibulum depth. RESULTS: A significant and stable increase of the attached gingiva is observed which led to better access for oral hygiene thus creating better conditions for successful long-term outcome. The root coverage was more that 40% and the tooth mobility was decreased to grade I. CONCLUSION: In the limitations of the presented case the free autogenous graft technique seems an appropriate approach in cases with deep Class IV recessions and high grade toot mobility in mandibular frontal area creating proper conditions for effective oral hygiene and decreasing tooth mobility by creating a sufficient amount of attached gingiva needed for the long term maintenance.

Evaluation of mRNA expression of the transcription factors of Th1 and Th2 subsets (T-bet and GATA-3) in periodontal health and disease - A pilot study in south Indian population.

Background:Based on their respective pro- or anti-inflammatory cytokine profiles, the Th1/Th2 paradigm explains pathogenic mechanisms involved in periodontal disease. Establishment of Th1 and Th2 subsets from a naive T-cell precursor depends on transcriptional regulation. The aim of this study was to compare the expression of master transcription factor regulators T-bet and GATA-3, respectively, to indicate the predominance of Th1 and Th2 subsets in the presence and absence of periodontal disease.Materials and Methods:A gingival tissue biopsy sample was obtained from each of 10 severe periodontitis patients (>5 mm attachment loss) and 10 periodontally healthy patients (no attachment loss). Biopsies were immediately processed by real-time reverse transcriptase polymerase chain reaction and the difference in mRNA expression of T-bet and GATA-3 was assessed for each group.Results:The mRNA expression of T-bet was marginally increased about 1.31-fold in disease, while the GATA-3 levels showed a significant decrease of 4.39-fold in disease.Conclusion:The advanced periodontal lesions lack Th2 cells, which produce anti-inflammatory cytokines. The biopsies were therefore dominated by Th1 cells, which activate macrophages and osteoclasts.

SUBGINGIVAL MICROBIOTA IN SEVERE CHRONIC PERIODONTITIS

SUMMARY Literature data relate certain Gram-negative anaerobe microorganisms with advanced destructive periodontal lesion. There are some references which reported higher levels of periodontal pathogens by the red and orange complex in deep periodontal pockets. The aim of this study is to determine the presence of most important periodontal pathogens and Candida spp. in deep periodontal pockets in patients with severe chronic periodontitis. The results of this study indicate the presence of high levels of periodontal pathogens in a strong connection with periodontal disease in deep periodontal pockets of patients studied.

Long‐term effects of supportive therapy in periodontal patients treated with fibre retention osseous resective surgery. II: tooth extractions during active and supportive therapy

Long-term tooth retention is the main objective of periodontal treatment. The aim of this retrospective study was to describe the prevalence and reasons of tooth extraction during active periodontal therapy (APT) and supportive periodontal care (SPC) in periodontal patients. Three hundred and four periodontal patients were examined. APT consisted of non-surgical periodontal treatment and fibre retention osseous resective surgery, where needed, to obtain no sites with PD>3 mm. All patients participated in an SPC programme for 3-17 years (mean time 7.8 years). At the initial examination, 45% of the patients had moderate periodontitis and 41% severe periodontitis. During APT, 576 teeth were extracted (7.5%). The main reason for tooth extraction during APT was the presence of advanced periodontal lesions (44%). The number of tooth extractions was higher in cases with severe periodontitis. Extracted teeth showed a mean bone loss of 76% of the total root length. During SPT, a total of 67 teeth were removed (0.9%) in a subgroup of 50 patients. The clinical problems were primarily related to the incidence of root fracture (48%) and secondarily to the progression of periodontal disease (30%). Prevalence of tooth extraction during APT is associated with the severity of periodontal disease. Tooth loss during supportive periodontal care may be negligible when a meticulous SPC programme is performed in patients where minimal probing depth is consequential to APT.

Potentiel pathogénique de Porphyromonas gingivalis, Treponema denticola et Tannerella forsythia, le complexe bactérien rouge associé à la parodontite

Periodontitis are mixed bacterial infections leading to destruction of tooth-supporting tissues, including periodontal ligament and alveolar bone. Among over 500 bacterial species living in the oral cavity, a bacterial complex named "red complex" and made of Porphyromonas gingivalis, Treponema denticola and Tannerella forsythia has been strongly related to advanced periodontal lesions. While periodontopathogenic bacteria are the primary etiologic factor of periodontitis, tissue destruction essentially results from the host immune response to the bacterial challenge. Members of the red complex are Gram negative anaerobic bacteria expressing numerous virulence factors allowing bacteria to colonize the subgingival sites, to disturb the host defense system, to invade and destroy periodontal tissue as well as to promote the immunodestructive host response. This article reviews current knowledge of the pathogenic mechanisms of bacteria of the red complex leading to tissue and alveolar bone destruction observed during periodontitis.

Subgingival Microbiota of Chilean Patients With Chronic Periodontitis

An association between race/ethnicity and the composition of the subgingival microbiota has been found in chronic periodontitis. A study was undertaken to determine the characteristics of the subgingival microbiota of chronic periodontitis in Chileans residing in Santiago. Twenty-six subjects (mean age 45 +/- 7 years) with chronic periodontitis, mean probing depth (PD) 2.63 +/- 0.5 mm, mean attachment level (AL) 3.70 +/- 0.77 mm, and without a history of periodontal therapy were selected. Measurements of PD, AL, bleeding on probing, and plaque accumulation were recorded at six sites per tooth. Subgingival plaque samples were taken from the mesial aspect of every tooth and evaluated for the presence, levels, and proportions of 40 bacterial taxa using whole genomic DNA probes and checkerboard DNA-DNA hybridization. The microbial data of the Chileans were compared with data from 115 chronic periodontitis patients from Boston, Massachusetts. Since several clinical and demographic parameters differed between the two populations, significance of differences for each species was determined using analysis of covariance, adjusting for age, plaque level, mean PD, gender, and smoking status. Each of the individual test species was present in at least 25 of the 26 subjects, and 12 subjects (46.1%) harbored all 40 test species. With the exception of Prevotella intermedia, all test species colonized more than 75% of sites, and 25 species colonized > or = 90% of sites including the co-colonizing species of advanced periodontal lesions, termed the red complex, composed of the three species Porphyromonas gingivalis, Tannerella forsythensis (formerly Bacteroides forsythus), and Treponema denticola as well as Fusobacterium nucleatum subspecies, Campylobacter rectus, Peptostreptococcus micros, and Treponerma socranskii. Sixteen of the 40 species differed significantly between Chilean and U.S. subjects. Red, yellow, and other complexes were significantly higher in the Chileans, while the Actinomyces were higher in the U.S. subjects. The composition of the subgingival plaque differs among different subject populations. Thus, care should be taken when extrapolating the findings of one study to different ethnic groups.

In situ detection of matrix metalloproteinase-9 (MMP-9) in gingival epithelium in human periodontal disease.

As the periodontal lesion develops, the junctional epithelium migrates apically in conjunction with the dissolution of the most coronal Sharpey's fibers. Because matrix metalloproteinase-9 (MMP-9) has been identified in migrating epithelial cells and invading tumors, we propose that this enzyme is produced by gingival keratinocytes in advanced periodontal lesions. To test this idea, biopsies of inflamed gingival tissues were obtained from patients with advanced periodontitis. Healthy gingival tissue samples were utilized as controls. The presence and activity of MMP-9 was evaluated by combining indirect immunofluorescence of gingival tissue samples and gelatin zymography of gingival epithelium separated from connective tissue. The staining pattern showed the presence of MMP-9 in junctional and pocket gingival epithelial cells, polymorphonuclear neutrophils (PMNs) and as a scattered deposit along connective tissues of periodontitis-affected gingival tissues. Gelatin zymography permitted the identification of pro-MMP-9 in surcular/pocket epithelium derived from inflamed gingival tissues. Lower levels of MMP-9 were detected in epithelium not exposed to inflammation. These observations suggest a role for MMP-9 in gingival epithelial response to periodontal infection.

Molecular analysis of bacteria in periodontitis: evaluation of clone libraries, novel phylotypes and putative pathogens.

Subgingival plaque samples were obtained from 26 subjects with advanced periodontal lesions. Bacterial diversity was analysed by amplification of the 16S rRNA genes with two different primer sets, and subsequent cloning and sequencing. A total of 578 sequences was analysed after the exclusion of chimeras. The authors found 148 phylotypes with the clone library 27f/519r (number of clones n=322; coverage, C=66 %) and 75 phylotypes with the clone library 515f/1525r (n=256; C=84 %). Comparative sequence analysis revealed that 70 % of all of the analysed sequences showed a similarity of at least 99 % to sequences deposited in public databases. The classes Actinobacteria, Bacilli, Bacteroidetes, Clostridia, Deferribacteres, Flavobacteria, Fusobacteria, Mollicutes, Spirochaetes and all classes of the Proteobacteria were represented. Sequences that were at least 99 % identical to Porphyromonas gingivalis, Filifactor alocis and Treponema socranskii were present in at least one-third of the patients. Libraries generated with the two PCR primer pairs differed significantly in their representation of the families Porphyromonadaceae, Prevotellaceae, Fusobacteriaceae, Eubacteriaceae, Streptococcaceae and ACIDAMINOCOCCACEAE: A total of 14 sequences exhibited less than 97 % identity to sequences published previously and were assigned to six different families within the phyla Bacteroidetes and FIRMICUTES: Twelve of 20 putative pathogens were recovered, which were recently proposed to be associated with periodontitis.

Dental disease in chinchillas in the UK.

Dental abnormalities are common in chinchillas, although knowledge of the lesions responsible for the clinical signs is incomplete. Animals bred in the UK were examined to gain further knowledge of dental disease in this chinchilla population. Dental abnormalities, particularly those related to tooth elongation, were detected on careful external examination of 35 per cent of apparently healthy chinchillas. Incisor abnormalities were seen on clinical examination in 55 per cent of chinchillas presented because of clinical illness. In all but one case, this occurred secondarily to crown elongation of the cheek teeth or to the absence of opposing teeth, rather than being a primary skeletal problem. Clinical signs commonly attributed to malocclusion, such as ventral mandibular swelling, weight loss, dysphagia, altered chewing pattern and changed food preferences, were not specific to malocclusion, being seen associated with coronal spike formation, root elongation and advanced periodontal lesions. Caries and resorptive lesions rarely caused clinical signs in this population, but were identified during 37 per cent of postmortem examinations. Congenital absence of teeth, skeletal malocclusion and pathological loss of teeth all resulted in significant clinical signs, but were rare. It is concluded that provision of a diet with physical properties more closely matching that of wild chinchillas should improve the dental health of captive animals.

Enhanced interleukin 1 beta, interleukin 6 and tumor necrosis factor alpha in gingival crevicular fluid from periodontal pockets of patients infected with human immunodeficiency virus 1.

Loss of periodontal support and eventually tooth loss is a common finding among acquired immunodeficiency syndrome (AIDS) patients. The cause of this destruction may be an increase in periodontal disease activity at sites within the same individual and also may be related to an increase in the pro-inflammatory cytokines, diffused through the gingival crevicular sulcus in AIDS patients. A study was undertaken to determine the relative levels of the pro-inflammatory cytokines, interleukin 1 beta (IL-1 beta), IL-6, and tumor necrosis factor alpha (TNF-alpha), in gingival crevicular fluid collected from the deep (> 5 mm periodontal pocket depth) and shallow (< or = 3 mm periodontal pocket depth) periodontal pockets of 39 HIV-1-infected patients and 20 age-, race- and sex-matched uninfected controls. Complete medical history including risk factors such as intravenous drug abuse was taken. Gingival crevicular fluid samples were collected on periopaper strips. Cytokines were estimated by solid-phase enzyme-linked immunosorbent assay. To assess the degree of HIV activity, the viral load of these patients was determined by an Amplicor HIV-1 monitor kit using reverse transcriptase polymerase chain reaction. Gingival crevicular fluid from HIV-1-infected patients showed a two-fold increase in both IL-1 beta and TNF-alpha in deep periodontal pockets in comparison to shallow pockets, whereas IL-6 increased 1.8-fold. There was a significant (P < 0.05) increase in IL-1 beta, IL-6 and TNF-alpha in gingival crevicular fluid (both shallow and deep pockets) from HIV-1-infected patients in comparison to uninfected controls and also significantly elevated in deep versus shallow pockets in these patients. Although IL-1 beta, L-6 and TNF-alpha levels among HIV-1-infected patients with a high viral load (> 10,000 copies/ml) were higher than those from patients with a low viral load (< 400 copies/ml), only the increase in IL-1 beta level associated with deep pockets was significant (P < 0.05). There was also a trend of an increase in all the three cytokines among intravenous drug-abusing HIV-1-infected patients in comparison to non-intravenous drug abusers, but only the difference in IL-1 beta levels from deep pockets reached significance (P < 0.05). These enhanced pro-inflammatory cytokine levels in the gingival crevicular fluid of HIV-positive patients may be an important factor in causing the advanced periodontal lesions sometimes observed in HIV-positive patients.

Oral Candida dubliniensis as a clinically important species in HIV-seropositive patients in the United States

Objective. Interest in Candida dubliniensis has led to renewed clinical investigations regarding incidence, drug resistance, pathogenesis, and epidemiology of fungal infections in patients with HIV. C dubliniensis phenotypically resembles Candida albicans in many respects, yet it can be identified and differentiated as a unique Candida species by its phenotypic and genetic profiles. The purpose of this study was to prospectively evaluate the prevalence of C dubliniensis in clinical isolates and determine the clinical and demographic characteristics of patients harboring C dubliniensis . Study Design. Over a 6-week period, 24 yeast-positive isolates from HIV-positive dental patients were screened for C dubliniensis through use of phenotypic criteria. HIV viral load, CD4 count, and complete oral health evaluations were performed on each patient at the same visit during which the oral fungal surveillance culture was taken. Results. Six isolates from 24 HIV-seropositive and yeast-positive patients were shown to be consistent phenotypically and by electrophoretic karyotyping with the European reference strain of C dubliniensis . Dose-dependent susceptibility to fluconazole was shown in one of the C dubliniensis isolates. Five of the 6 patients demonstrated moderate to high viral loads. General oral health, as evidenced by the presence of advanced periodontal lesions and a high decayed, missing, and filled teeth index (>20), was poor in 3 of the 6 patients with C dubliniensis and 7 of the 18 patients with C albicans . A history of intravenous drug abuse was present in 50% of the C dubliniensis –positive patients, which is representative of the HIV-positive population at the hospital. Conclusions. In this small sample, C dubliniensis represented 25% of the yeast-positive cultures. The clinical significance of this interesting species in the United States may be related to high viral load, rapid AIDS progression, and/or concomitant oral disease, such as a high caries index or periodontal disease. (Oral Surg Oral Med Oral Pathol Oral Radiol Endod 1999;88:573-80)

Treponema amylovorum sp. nov., a saccharolytic spirochete of medium size isolated from an advanced human periodontal lesion.

A highly motile, medium-size, saccharolytic spirochete was isolated from an advanced human periodontal lesion in medium OMIZ-Pat supplemented with 1% human serum. The growth of this organism is dependent on either glucose, maltose, starch, or glycogen. The cells contain six endoflagella, three per pole, which overlap in the central region of the cell body. On the basis of its cell morphology and enzyme activities, as well as its sodium dodecyl sulfate-polyacrylamide gel electrophoresis protein and antigen profiles, this organism is clearly distinct from all previously cultured spirochetes. The presence of a novel species is supported by the 16S rRNA sequence of this organism, which places it in phylotype 19 of Choi et al. (B. K. Choi, B. J. Paster, F. E. Dewhirst, and U. B. Göbel, Infect. Immun. 62:1889-1895, 1994). The only isolate, strain HA2P, is designated the type strain of a novel species, for which we propose the name Treponema amylovorum.

A Case of Myiasis Gingiva

A case of myiasis gingiva was diagnosed in an investigation designed to evaluate the histopathological features of the adjacent tissues of 100 advanced periodontal lesions. The patient was a 36-year old female and her chief complaint was discomfort and swelling in the area between the upper left central and lateral incisors. The patient's medical history, review of the symptoms, and family history were non-contributory and her oral hygiene was acceptable. The surgeon was not aware of anything unusual during the operation. Although the Parasitology Department was unable to define the entomologic identification of the infesting parasite from histopathological tissue slides, it was agreed that this case of myiasis might be produced by larvae of genus Sarcophaga or Enterobius vermicularis.

Isolation of periodontal species after guided tissue regeneration.

One advanced localized periodontal lesion in each of 10 patients was treated using the guided tissue regeneration procedure. Six weeks after placement of expanded polytetrafluoroethylene (ePTFE) membranes, microbial samples were taken from each treated site and the membranes were removed. Six weeks later the cases were re-evaluated. They had all healed successfully with varying amounts of gain of clinical attachment. Gram-negative, anaerobic rods were found in all samples and made up 31% of all organisms cultivated. In 1 patient, Porphyromonas gingivalis was found in a proportion of 17.5%. Six of the other 9 patients harbored Prevotella intermedia (mean proportion 21.3%) and 6 Prevotella melaninogenica (6.8%). Fusobacterium and Capnocytophaga were also frequently found. The results demonstrate that ePTFE membranes are frequently colonized by periodontal microorganisms. The importance of bacterial colonization on clinical success is presently not known. Further studies are needed to determine the effect of the presence or absence of putative pathogens during guided tissue regeneration.

Vascular expansion in chronic periodontitis

Animal studies have demonstrated expansion and remodelling of gingival blood vessels in inflamed gingival tissues. However, there is a paucity of information, regarding the vascular response in human gingivitis and periodontitis. In this study, gingival biopsies were obtained from 51 separate patients. Fifteen minimally inflamed, 16 gingivitis and 20 periodontitis specimens were studied. Gingival biopsies were divided into five fields, and a quantitative survey of vascular changes was performed. In fields adjacent to the bacterial plaque irritant, vessel profiles were increased in number with the development of the advanced periodontal lesion. The diameter of blood vessels throughout the entire thickness of gingival biopsies was found to increase with advancing periodontal disease. It is concluded that considerable remodelling of the gingival vasculature occurs in chronic periodontitis, and that this may contribute to the tissue destruction seen in this disease.

Monitoring of subgingival Bacteroides gingivalis and Actinobacillus actinomycetemcomitans in the management of advanced periodontitis.

In a series of clinical trials involving 79 adult periodontitis patients, we evaluated the clinical and microbiological effects of H2O2, NaHCO3, and a commercially available povidine solution, as adjuncts to mechanical periodontal debridement. Each trial included a placebo as a control. The healing response was monitored clinically by measurement of changes in probing attachment levels after treatment. The current report includes data from single-rooted teeth only.In general, healing in severely advanced periodontal lesions (initial pocket depth ≥ 7 mm) was enhanced by the use of the listed topical antimicrobial agents administered subgingivally during mechanical debridement.Correlations were sought between changes in probing attachment levels 12 months after treatment, and the presence of subgingival B. gingivalis and A. actinomycetemcomitans in the periodontal lesions. For a total of 428 lesions included in this report, B. gingivalis was detected in 53.1% of lesions showing probing attachment loss (≥1.5 mm), but in only 4.7% of lesions showing gain (≥ 1.5 mm). Either B. gingivalis or A. actinomycetemcomitans was detected in 70.1% of the lesions showing loss and in only 4.8% of those showing gain. These studies indicate the benefits of the adjunctive antimicrobial therapy described, and the usefulness of specific microbiological monitoring as an aid to clinical measurements in the evaluation of success or failure of treatment of chronic adult periodontitis.

Bacteroides gingivalis, Bacteroides intermedius and Actinobacillus actinomycetemcomitans in human periodontal diseases.

Bacteroides gingivalis, Bacteroides intermedius and Actinobacillus actinomycetemcomitans seem to be major pathogens in advancing periodontitis in man. First, these organisms are recovered in higher prevalence and proportions from progressive periodontitis lesions than from quiescent periodontal sites. Second, antibody levels against B. gingivalis and A. actinomycetemcomitans are markedly elevated in serum and gingival crevice fluid of periodontitis patients compared to normal controls. Third, B. gingivalis and B. intermedius elaborate potent proteases and A. actinomycetemcomitans various noxious substances which have the potential to perturb important host defenses and to disintegrate key constituents of the periodontal tissues. Monitoring these bacteria in advanced periodontal lesions may greatly assist the assessment of treatment efficacy and risk of further periodontal breakdown.